.drone.yml

@@ -7,13 +7,13 @@
 
     steps:
     - name: test
-      image: mcr.microsoft.com/dotnet/sdk:5.0.102-ca-patch-buster-slim
+      image: mcr.microsoft.com/dotnet/core/sdk:3.1
       commands:
         - dotnet build -c Release
         - dotnet test -c Release
 
     - name: deploy
-      image: mcr.microsoft.com/dotnet/sdk:5.0.102-ca-patch-buster-slim
+      image: mcr.microsoft.com/dotnet/core/sdk:3.1
       environment:
         API_KEY:
           from_secret: API_KEY

LICENSE

@@ -1,19 +1,415 @@
 encompass-cs
+Copyright Evan Hemsley 2019
 
-Copyright (c) 2020 Evan Hemsley <evan@moonside.games>
+COOPERATIVE SOFTWARE LICENSE
 
-This software is provided 'as-is', without any express or implied
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+AND CONDITIONS OF THIS LICENSE.
 
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TODO

@@ -0,0 +1,7 @@
+- immutable component system?
+
+- method to remove all components of a type without destroying Entities
+- method to remove a component of a type without destroying entity
+
+- look at test coverage
+- docs

encompass-cs.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 16
+# Visual Studio 15
-VisualStudioVersion = 16.0.30717.126
+VisualStudioVersion = 15.0.26124.0
 MinimumVisualStudioVersion = 15.0.26124.0
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "encompass-cs", "encompass-cs\encompass-cs.csproj", "{B862FC25-0740-4CEA-BC53-3C5F43DCD985}"
 EndProject
@@ -9,28 +9,38 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "test", "test\test.csproj",
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
 		Debug|x64 = Debug|x64
 		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
 		Release|x64 = Release|x64
 		Release|x86 = Release|x86
 	EndGlobalSection
 	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x64.ActiveCfg = Debug|x64
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x64.Build.0 = Debug|x64
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x86.ActiveCfg = Debug|x86
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x86.Build.0 = Debug|x86
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x64.Build.0 = Debug|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x64.ActiveCfg = Release|x64
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x64.Build.0 = Release|x64
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Debug|x86.Build.0 = Debug|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x86.ActiveCfg = Release|x86
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x86.Build.0 = Release|x86
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|Any CPU.Build.0 = Release|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x64.ActiveCfg = Debug|x64
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x64.ActiveCfg = Release|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x64.Build.0 = Debug|x64
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x64.Build.0 = Release|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x86.ActiveCfg = Debug|x86
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x86.ActiveCfg = Release|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x86.Build.0 = Debug|x86
+		{B862FC25-0740-4CEA-BC53-3C5F43DCD985}.Release|x86.Build.0 = Release|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x64.ActiveCfg = Release|x64
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x64.Build.0 = Release|x64
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x86.ActiveCfg = Release|x86
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x86.Build.0 = Release|x86
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x64.Build.0 = Debug|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Debug|x86.Build.0 = Debug|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|Any CPU.Build.0 = Release|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x64.ActiveCfg = Release|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x64.Build.0 = Release|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x86.ActiveCfg = Release|Any CPU
+		{23D6C29C-A310-4D3E-8455-8D0B8CA1FC06}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

encompass-cs/Attributes/Adds.cs

@@ -1,16 +0,0 @@
-using System;
-using System.Collections.Generic;
-
-namespace Encompass
-{
-    [AttributeUsage(AttributeTargets.Class)]
-    public class Adds : Attribute
-    {
-        public readonly HashSet<Type> addTypes;
-
-        public Adds(params Type[] addTypes)
-        {
-            this.addTypes = new HashSet<Type>(addTypes);
-        }
-    }
-}

encompass-cs/Attributes/DefaultWritePriority.cs

@@ -5,11 +5,11 @@ namespace Encompass
     [AttributeUsage(AttributeTargets.Class)]
     public class DefaultWritePriority : Attribute
     {
-        public int WritePriority { get; }
+        public int writePriority;
 
         public DefaultWritePriority(int writePriority)
         {
-            WritePriority = writePriority;
+            this.writePriority = writePriority;
         }
     }
 }

encompass-cs/Attributes/QueryWith.cs

@@ -1,19 +1,27 @@
 using Encompass.Exceptions;
 using System;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class QueryWith : Attribute
     {
-        public readonly HashSet<Type> QueryWithTypes = new HashSet<Type>();
+        public readonly HashSet<Type> queryWithTypes = new HashSet<Type>();
 
         public QueryWith(params Type[] queryWithTypes)
         {
             foreach (var queryWithType in queryWithTypes)
             {
-                QueryWithTypes.Add(queryWithType);
+                var isComponent = queryWithType.GetInterfaces().Contains(typeof(IComponent));
+
+                if (!isComponent)
+                {
+                    throw new IllegalReadTypeException("{0} must be a Component", queryWithType.Name);
+                }
+
+                this.queryWithTypes.Add(queryWithType);
             }
         }
     }

encompass-cs/Attributes/QueryWithout.cs

@@ -1,18 +1,27 @@
-using System;
+using Encompass.Exceptions;
+using System;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class QueryWithout : Attribute
     {
-        public readonly HashSet<Type> QueryWithoutTypes = new HashSet<Type>();
+        public readonly HashSet<Type> queryWithoutTypes = new HashSet<Type>();
 
         public QueryWithout(params Type[] queryWithoutTypes)
         {
             foreach (var type in queryWithoutTypes)
             {
-                QueryWithoutTypes.Add(type);
+                var isComponent = type.GetInterfaces().Contains(typeof(IComponent));
+
+                if (!isComponent)
+                {
+                    throw new IllegalReadTypeException("{0} must be a Component", type.Name);
+                }
+
+                this.queryWithoutTypes.Add(type);
             }
         }
     }

encompass-cs/Attributes/Reads.cs

@@ -1,18 +1,27 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class Reads : Attribute
     {
-        public readonly HashSet<Type> ReadTypes = new HashSet<Type>();
+        public readonly HashSet<Type> readTypes = new HashSet<Type>();
 
         public Reads(params Type[] readTypes)
         {
             foreach (var readType in readTypes)
             {
-                ReadTypes.Add(readType);
+                var isComponent = readType.GetInterfaces().Contains(typeof(IComponent));
+
+                if (!isComponent)
+                {
+                    throw new IllegalReadTypeException("{0} must be a Component", readType.Name);
+                }
+
+                this.readTypes.Add(readType);
             }
         }
     }

encompass-cs/Attributes/ReadsImmediate.cs

@@ -1,18 +1,27 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class ReadsImmediate : Attribute
     {
-        public readonly HashSet<Type> ReadImmediateTypes = new HashSet<Type>();
+        public readonly HashSet<Type> readImmediateTypes = new HashSet<Type>();
 
         public ReadsImmediate(params Type[] readImmediateTypes)
         {
             foreach (var readImmediateType in readImmediateTypes)
             {
-                ReadImmediateTypes.Add(readImmediateType);
+                var isComponent = readImmediateType.GetInterfaces().Contains(typeof(IComponent));
+
+                if (!isComponent)
+                {
+                    throw new IllegalReadTypeException("{0} must be a Component", readImmediateType.Name);
+                }
+
+                this.readImmediateTypes.Add(readImmediateType);
             }
         }
     }

encompass-cs/Attributes/Receives.cs

@@ -1,16 +1,27 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class Receives : Attribute
     {
-        public readonly HashSet<Type> ReceiveTypes;
+        public readonly HashSet<Type> receiveTypes;
 
         public Receives(params Type[] receiveTypes)
         {
-            ReceiveTypes = new HashSet<Type>(receiveTypes);
+            foreach (var receiveType in receiveTypes)
+            {
+                var isMessage = receiveType.GetInterfaces().Contains(typeof(IMessage));
+                if (!isMessage)
+                {
+                    throw new IllegalSendTypeException("{0} must be a Message", receiveType.Name);
+                }
+            }
+
+            this.receiveTypes = new HashSet<Type>(receiveTypes);
         }
     }
 }

encompass-cs/Attributes/Sends.cs

@@ -1,16 +1,27 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class Sends : Attribute
     {
-        public readonly HashSet<Type> SendTypes;
+        public readonly HashSet<Type> sendTypes;
 
         public Sends(params Type[] sendTypes)
         {
-            this.SendTypes = new HashSet<Type>(sendTypes);
+            foreach (var sendType in sendTypes)
+            {
+                var isMessage = sendType.GetInterfaces().Contains(typeof(IMessage));
+                if (!isMessage)
+                {
+                    throw new IllegalSendTypeException("{0} must be a Message", sendType.Name);
+                }
+            }
+
+            this.sendTypes = new HashSet<Type>(sendTypes);
         }
     }
 }

encompass-cs/Attributes/Writes.cs

@@ -1,26 +1,40 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
     public class Writes : Attribute
     {
-        public readonly HashSet<Type> WriteTypes = new HashSet<Type>();
+        public readonly HashSet<Type> writeTypes = new HashSet<Type>();
-        public readonly Dictionary<Type, int> Priorities = new Dictionary<Type, int>();
+        public Dictionary<Type, int> priorities = new Dictionary<Type, int>();
 
         public Writes(params Type[] writeTypes)
         {
             foreach (var writeType in writeTypes)
             {
-                WriteTypes.Add(writeType);
+                var isComponent = writeType.GetInterfaces().Contains(typeof(IComponent));
+                if (!isComponent)
+                {
+                    throw new IllegalWriteTypeException("{0} must be a Component", writeType.Name);
+                }
+
+                this.writeTypes.Add(writeType);
             }
         }
 
         public Writes(Type writeType, int priority)
         {
-            WriteTypes.Add(writeType);
+            var isComponent = writeType.GetInterfaces().Contains(typeof(IComponent));
-            Priorities.Add(writeType, priority);
+            if (!isComponent)
+            {
+                throw new IllegalWriteTypeException("{0} must be a Component", writeType.Name);
+            }
+
+            writeTypes.Add(writeType);
+            priorities.Add(writeType, priority);
         }
     }
 }

encompass-cs/Attributes/WritesImmediate.cs

@@ -1,18 +1,26 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
 
 namespace Encompass
 {
     [AttributeUsage(AttributeTargets.Class)]
     public class WritesImmediate : Attribute
     {
-        public readonly HashSet<Type> WriteImmediateTypes = new HashSet<Type>();
+        public readonly HashSet<Type> writeImmediateTypes = new HashSet<Type>();
 
         public WritesImmediate(params Type[] writeImmediateTypes)
         {
             foreach (var writeImmediateType in writeImmediateTypes)
             {
-                WriteImmediateTypes.Add(writeImmediateType);
+                var isComponent = writeImmediateType.GetInterfaces().Contains(typeof(IComponent));
+                if (!isComponent)
+                {
+                    throw new IllegalWriteImmediateTypeException("{0} must be a Component", writeImmediateType.Name);
+                }
+
+                this.writeImmediateTypes.Add(writeImmediateType);
             }
         }
     }

encompass-cs/Collections/BitSet512.cs

@@ -1,156 +0,0 @@
-using System;
-
-namespace Encompass
-{
-    public static unsafe class MemoryHelper
-    {
-        public static void Copy(uint* src, uint* dest, int count)
-        {
-            for (; count != 0; count--) *dest++ = *src++;
-        }
-
-        public static void Fill(uint* p, int count, uint value)
-        {
-            for (; count != 0; count--) *p++ = value;
-        }
-
-        public static void And(uint* p, uint* q, uint* result, int count)
-        {
-            for (; count != 0; count--) *result++ = *p++ & *q++;
-        }
-
-        public static void Or(uint* p, uint* q, uint* result, int count)
-        {
-            for (; count != 0; count--) *result++ = *p++ | *q++;
-        }
-
-        public static void Not(uint* p, uint* result, int count)
-        {
-            for (; count != 0; count--) *result++ = ~*p++;
-        }
-
-        public static bool Equal(uint* p, uint* q, int count)
-        {
-            for (; count != 0; count--) if (*p++ != *q++) { return false;  }
-            return true;
-        }
-    }
-
-    public unsafe struct BitSet512 : IEquatable<BitSet512>
-    {
-        public static BitSet512 Zero { get; } = new BitSet512(0);
-        public static BitSet512 Ones { get; } = new BitSet512(uint.MaxValue);
-
-        private const int _uintLength = 16;
-
-        private fixed uint _buffer[_uintLength];
-
-        public BitSet512(uint value)
-        {
-            fixed (uint* p = _buffer) MemoryHelper.Fill(p, _uintLength, value);
-        }
-
-        public BitSet512(uint* src)
-        {
-            fixed (uint* dest = _buffer) MemoryHelper.Copy(src, dest, _uintLength);
-        }
-
-        public static BitSet512 operator &(BitSet512 a, BitSet512 b)
-        {
-            var tmp = stackalloc uint[_uintLength];
-            MemoryHelper.And(a._buffer, b._buffer, tmp, _uintLength);
-            return new BitSet512(tmp);
-        }
-
-        public static BitSet512 operator |(BitSet512 a, BitSet512 b)
-        {
-            var tmp = stackalloc uint[_uintLength];
-            MemoryHelper.Or(a._buffer, b._buffer, tmp, _uintLength);
-            return new BitSet512(tmp);
-        }
-
-        public static BitSet512 operator ~(BitSet512 a)
-        {
-            var tmp = stackalloc uint[_uintLength];
-            MemoryHelper.Not(a._buffer, tmp, _uintLength);
-            return new BitSet512(tmp);
-        }
-
-        public static bool operator ==(BitSet512 left, BitSet512 right)
-        {
-            return left.Equals(right);
-        }
-
-        public static bool operator !=(BitSet512 left, BitSet512 right)
-        {
-            return !(left == right);
-        }
-
-        public BitSet512 Set(int index)
-        {
-            var tmp = stackalloc uint[_uintLength];
-            fixed (uint* p = _buffer) MemoryHelper.Copy(p, tmp, _uintLength);
-            tmp[index / 32] |= (uint)(1 << index % 32);
-            return new BitSet512(tmp);
-        }
-
-        public BitSet512 UnSet(int index)
-        {
-            var tmp = stackalloc uint[_uintLength];
-            fixed (uint* p = _buffer) MemoryHelper.Copy(p, tmp, _uintLength);
-            tmp[index / 32] &= ~(uint)(1 << index % 32);
-            return new BitSet512(tmp);
-        }
-
-        public bool Get(int bitIndex)
-        {
-            var bitInt = (uint)(1 << bitIndex % 32);
-            return (_buffer[bitIndex / 32] & bitInt) == bitInt;
-        }
-
-        public bool AllTrue()
-        {
-            return this == Ones;
-        }
-
-        public bool AllFalse()
-        {
-            return this == Zero;
-        }
-
-        public static BitSet512 BitwiseAnd(BitSet512 left, BitSet512 right)
-        {
-            return left & right;
-        }
-
-        public static BitSet512 BitwiseOr(BitSet512 left, BitSet512 right)
-        {
-            return left | right;
-        }
-
-        public static BitSet512 OnesComplement(BitSet512 bitSet)
-        {
-            return ~bitSet;
-        }
-
-        public override bool Equals(object obj)
-        {
-            return obj is BitSet512 set && Equals(set);
-        }
-
-        public bool Equals(BitSet512 other)
-        {
-            fixed (uint* p = _buffer) return MemoryHelper.Equal(p, other._buffer, _uintLength);
-        }
-
-        public override int GetHashCode()
-        {
-            var hc = 0;
-            for (var i = 0; i < _uintLength; i++)
-            {
-                hc ^= _buffer[i].GetHashCode();
-            }
-            return hc;
-        }
-    }
-}

encompass-cs/Collections/ComponentBitSet.cs

@@ -1,3 +1,4 @@
+using MoonTools.FastCollections;
 using System;
 using System.Collections.Generic;
 
@@ -5,49 +6,49 @@ namespace Encompass
 {
     internal class ComponentBitSet
     {
-        private readonly Dictionary<int, BitSet512> _entities = new Dictionary<int, BitSet512>();
+        Dictionary<int, BitSet512> entities = new Dictionary<int, BitSet512>();
-        private readonly Dictionary<Type, int> _typeToIndex;
+        Dictionary<Type, int> TypeToIndex { get; }
 
         public ComponentBitSet(Dictionary<Type, int> typeToIndex)
         {
-            _typeToIndex = typeToIndex;
+            TypeToIndex = typeToIndex;
         }
 
         public void Clear()
         {
-            _entities.Clear();
+            entities.Clear();
         }
 
         public void AddEntity(int entityID)
         {
-            _entities.Add(entityID, BitSet512.Zero);
+            entities.Add(entityID, BitSet512.Zero);
         }
 
-        public void Set<TComponent>(int entityID) where TComponent : struct
+        public void Set<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            if (!_entities.ContainsKey(entityID)) { AddEntity(entityID); }
+            if (!entities.ContainsKey(entityID)) { AddEntity(entityID); }
-            _entities[entityID] = _entities[entityID].Set(_typeToIndex[typeof(TComponent)]);
+            entities[entityID] = entities[entityID].Set(TypeToIndex[typeof(TComponent)]);
         }
 
-        public void RemoveComponent<TComponent>(int entityID) where TComponent : struct
+        public void RemoveComponent<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            if (_entities.ContainsKey(entityID))
+            if (entities.ContainsKey(entityID))
             {
-                _entities[entityID] = _entities[entityID].UnSet(_typeToIndex[typeof(TComponent)]);
+                entities[entityID] = entities[entityID].UnSet(TypeToIndex[typeof(TComponent)]);
             }
         }
 
         public void RemoveEntity(int entityID)
         {
-            if (_entities.ContainsKey(entityID))
+            if (entities.ContainsKey(entityID))
             {
-                _entities.Remove(entityID);
+                entities.Remove(entityID);
             }
         }
 
         public BitSet512 EntityBitArray(int entityID)
         {
-            return _entities.ContainsKey(entityID) ? _entities[entityID] : BitSet512.Zero;
+            return entities.ContainsKey(entityID) ? entities[entityID] : BitSet512.Zero;
         }
     }
 }

encompass-cs/Collections/ComponentDeltaStore.cs

@@ -3,48 +3,39 @@ using System.Collections.Generic;
 
 namespace Encompass
 {
-    internal class ComponentDeltaStore
+    internal class ComponentDeltaStore : ComponentStore
     {
-        private readonly ComponentStore _store;
         private readonly Dictionary<Type, Replayer> _replayers = new Dictionary<Type, Replayer>();
         private readonly HashSet<Replayer> _currentReplayers = new HashSet<Replayer>();
 
         public IEnumerable<Replayer> CurrentReplayers { get { return _currentReplayers; } }
 
-        public ComponentDeltaStore(Dictionary<Type, int> typeToIndex)
+        public ComponentDeltaStore(Dictionary<Type, int> typeToIndex) : base(typeToIndex)
         {
-            _store = new ComponentStore(typeToIndex);
         }
 
-        public void RegisterComponentType<TComponent>() where TComponent : struct
+        public override void RegisterComponentType<TComponent>()
         {
-            _store.RegisterComponentType<TComponent>();
+            base.RegisterComponentType<TComponent>();
             if (!_replayers.ContainsKey(typeof(TComponent)))
             {
                 _replayers.Add(typeof(TComponent), new Replayer<TComponent>(this));
             }
         }
 
-        public ref readonly TComponent GetComponent<TComponent>(int entityID) where TComponent : struct
+        public override void Set<TComponent>(int entityID, TComponent component)
         {
-            return ref _store.Get<TComponent>(entityID);
+            base.Set(entityID, component);
-        }
-
-        public void Set<TComponent>(int entityID, in TComponent component) where TComponent : struct
-        {
-            _store.Set(entityID, component);
-            RegisterComponentType<TComponent>();
             var replayer = _replayers[typeof(TComponent)];
             _currentReplayers.Add(replayer);
             replayer.UnMarkRemoval(entityID);
         }
 
-        public bool Set<TComponent>(int entityID, TComponent component, int priority) where TComponent : struct
+        public override bool Set<TComponent>(int entityID, TComponent component, int priority)
         {
-            var result = _store.Set(entityID, component, priority);
+            var result = base.Set(entityID, component, priority);
             if (result)
             {
-                RegisterComponentType<TComponent>();
                 var replayer = _replayers[typeof(TComponent)];
                 _currentReplayers.Add(replayer);
                 replayer.UnMarkRemoval(entityID);
@@ -52,12 +43,11 @@ namespace Encompass
             return result;
         }
 
-        public bool Remove<TComponent>(int entityID, int priority) where TComponent : struct
+        public override bool Remove<TComponent>(int entityID, int priority)
         {
-            var result = _store.Remove<TComponent>(entityID, priority);
+            var result = base.Remove<TComponent>(entityID, priority);
             if (result)
             {
-                RegisterComponentType<TComponent>();
                 var replayer = _replayers[typeof(TComponent)];
                 _currentReplayers.Add(replayer);
                 replayer.MarkRemoval(entityID);
@@ -65,23 +55,18 @@ namespace Encompass
             return result;
         }
 
-        public void Remove(int entityID)
+        public override void Remove(int entityID)
         {
-            _store.Remove(entityID);
+            base.Remove(entityID);
             foreach (var replayer in CurrentReplayers)
             {
                 replayer.MarkRemoval(entityID);
             }
         }
 
-        public ReadOnlySpan<Entity> AllEntities<TComponent>() where TComponent : struct
+        public override void ClearAll()
         {
-            return _store.AllEntities<TComponent>();
+            base.ClearAll();
-        }
-
-        public void ClearAll()
-        {
-            _store.ClearAll();
             foreach (var replayer in _currentReplayers)
             {
                 replayer.Clear();

encompass-cs/Collections/ComponentStore.cs

@@ -1,45 +1,49 @@
-using Encompass.Exceptions;
+using MoonTools.FastCollections;
 using System;
 using System.Collections.Generic;
 
 namespace Encompass
 {
-    internal sealed class ComponentStore
+    internal class ComponentStore
     {
-        private Dictionary<Type, TypedComponentStore> _stores = new Dictionary<Type, TypedComponentStore>(512);
+        private Dictionary<Type, TypedComponentStore> Stores = new Dictionary<Type, TypedComponentStore>(512);
         public ComponentBitSet ComponentBitSet { get; private set; }
-        private readonly Dictionary<Type, int> _typeToIndex;
 
         public ComponentStore(Dictionary<Type, int> typeToIndex)
         {
-            _typeToIndex = typeToIndex;
             ComponentBitSet = new ComponentBitSet(typeToIndex);
         }
 
-        public void RegisterComponentType<TComponent>() where TComponent : struct
+        public IEnumerable<(Type, TypedComponentStore)> StoresEnumerable()
         {
-            if (!_stores.ContainsKey(typeof(TComponent)))
+            foreach (var entry in Stores)
+            {
+                yield return (entry.Key, entry.Value);
+            }
+        }
+
+        public virtual void RegisterComponentType<TComponent>() where TComponent : struct, IComponent
+        {
+            if (!Stores.ContainsKey(typeof(TComponent)))
             {
                 var store = new TypedComponentStore<TComponent>();
-                _stores.Add(typeof(TComponent), store);
+                Stores.Add(typeof(TComponent), store);
             }
-
-            if (!_typeToIndex.ContainsKey(typeof(TComponent))) { _typeToIndex.Add(typeof(TComponent), _typeToIndex.Count); }
         }
 
-        private TypedComponentStore<TComponent> Lookup<TComponent>() where TComponent : struct
+        private TypedComponentStore<TComponent> Lookup<TComponent>() where TComponent : struct, IComponent
         {
-            return _stores[typeof(TComponent)] as TypedComponentStore<TComponent>;
+            return Stores[typeof(TComponent)] as TypedComponentStore<TComponent>;
         }
 
-        public bool Has<TComponent>(int entityID) where TComponent : struct
+        public bool Has<TComponent>(int entityID) where TComponent : struct, IComponent
         {
             return Lookup<TComponent>().Has(entityID);
         }
 
         public bool Has(Type type, int entityID)
         {
-            return _stores[type].Has(entityID);
+            return Stores.ContainsKey(type) && Stores[type].Has(entityID);
         }
 
         public BitSet512 EntityBitArray(int entityID)
@@ -47,32 +51,18 @@ namespace Encompass
             return ComponentBitSet.EntityBitArray(entityID);
         }
 
-        public ref TComponent Get<TComponent>(int entityID) where TComponent : struct
+        public TComponent Get<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return ref Lookup<TComponent>().Get(entityID);
+            return Lookup<TComponent>().Get(entityID);
         }
 
-        public ref readonly TComponent Singular<TComponent>() where TComponent : struct
+        public virtual void Set<TComponent>(int entityID, TComponent component) where TComponent : struct, IComponent
-        {
-            if (!Any<TComponent>()) { throw new NoComponentOfTypeException("No component of type {0} exists", typeof(TComponent).Name); }
-
-            return ref Lookup<TComponent>().Singular();
-        }
-
-        public ref readonly Entity SingularEntity<TComponent>() where TComponent : struct
-        {
-            if (!Any<TComponent>()) { throw new NoComponentOfTypeException("No component of type {0} exists", typeof(TComponent).Name); }
-
-            return ref Lookup<TComponent>().SingularEntity();
-        }
-
-        public void Set<TComponent>(int entityID, in TComponent component) where TComponent : struct
         {
             Lookup<TComponent>().Set(entityID, component);
             ComponentBitSet.Set<TComponent>(entityID);
         }
 
-        public bool Set<TComponent>(int entityID, in TComponent component, int priority) where TComponent : struct
+        public virtual bool Set<TComponent>(int entityID, TComponent component, int priority) where TComponent : struct, IComponent
         {
             if (Lookup<TComponent>().Set(entityID, component, priority))
             {
@@ -82,7 +72,7 @@ namespace Encompass
             return false;
         }
 
-        public bool Remove<TComponent>(int entityID, int priority) where TComponent : struct
+        public virtual bool Remove<TComponent>(int entityID, int priority) where TComponent : struct, IComponent
         {
             if (Lookup<TComponent>().Remove(entityID, priority))
             {
@@ -92,63 +82,59 @@ namespace Encompass
             return false;
         }
 
-        public void ForceRemove<TComponent>(int entityID) where TComponent : struct
+        public void ForceRemove<TComponent>(int entityID) where TComponent : struct, IComponent
         {
             Lookup<TComponent>().ForceRemove(entityID);
             ComponentBitSet.RemoveComponent<TComponent>(entityID);
         }
 
-        public void Remove(int entityID)
+        public virtual void Remove(int entityID)
         {
-            foreach (var entry in _stores.Values)
+            foreach (var entry in Stores.Values)
             {
                 entry.ForceRemove(entityID);
             }
             ComponentBitSet.RemoveEntity(entityID);
         }
 
-        public bool Any<TComponent>() where TComponent : struct
+        public bool Any<TComponent>() where TComponent : struct, IComponent
         {
             return Lookup<TComponent>().Count > 0;
         }
 
-        public ReadOnlySpan<TComponent> All<TComponent>() where TComponent : struct
+        public IEnumerable<(int, Type, IComponent)> AllInterfaceTyped()
         {
-            return Lookup<TComponent>().AllComponents();
+            foreach (var store in Stores.Values)
+            {
+                foreach (var thing in store.AllInterfaceTyped())
+                {
+                    yield return thing;
+                }
+            }
         }
 
-        public IEnumerable<TComponent> AllAsEnumerable<TComponent>() where TComponent : struct
+        public IEnumerable<(TComponent, int)> All<TComponent>() where TComponent : struct, IComponent
         {
-            return Lookup<TComponent>().AllComponentsAsEnumerable();
+            return Lookup<TComponent>().All();
         }
 
-        public ReadOnlySpan<Entity> AllEntities<TComponent>() where TComponent : struct
+        public void Clear<TComponent>() where TComponent : struct, IComponent
-        {
-            return Lookup<TComponent>().AllEntities();
-        }
-
-        public IEnumerable<Entity> AllEntitiesAsEnumerable<TComponent>() where TComponent : struct
-        {
-            return Lookup<TComponent>().AllEntitiesAsEnumerable();
-        }
-
-        public void Clear<TComponent>() where TComponent : struct
         {
             Lookup<TComponent>().Clear();
         }
 
-        public void ClearAllPriorities()
+        public virtual void ClearAllPriorities()
         {
-            foreach (var store in _stores.Values)
+            foreach (var store in Stores.Values)
             {
                 store.ClearPriorities();
             }
         }
 
-        public void ClearAll()
+        public virtual void ClearAll()
         {
             ComponentBitSet.Clear();
-            foreach (var store in _stores.Values)
+            foreach (var store in Stores.Values)
             {
                 store.Clear();
             }
@@ -156,7 +142,7 @@ namespace Encompass
 
         public void SwapWith(ComponentStore other)
         {
-            (_stores, other._stores) = (other._stores, _stores);
+            (Stores, other.Stores) = (other.Stores, Stores);
             (ComponentBitSet, other.ComponentBitSet) = (other.ComponentBitSet, ComponentBitSet);
         }
 

encompass-cs/Collections/MessageStore.cs

@@ -1,74 +1,66 @@
 using System;
 using System.Collections.Generic;
-using Encompass.Exceptions;
 
 namespace Encompass
 {
     internal class MessageStore
     {
-        private readonly Dictionary<Type, TypedMessageStore> _stores = new Dictionary<Type, TypedMessageStore>(512);
+        private Dictionary<Type, TypedMessageStore> Stores = new Dictionary<Type, TypedMessageStore>(512);
 
-        private void RegisterMessageType<TMessage>() where TMessage : struct
+        private void RegisterMessageType<TMessage>() where TMessage : struct, IMessage
         {
-            _stores.Add(typeof(TMessage), new TypedMessageStore<TMessage>());
+            Stores.Add(typeof(TMessage), new TypedMessageStore<TMessage>());
         }
 
-        private TypedMessageStore<TMessage> Lookup<TMessage>() where TMessage : struct
+        private TypedMessageStore<TMessage> Lookup<TMessage>() where TMessage : struct, IMessage
         {
-            if (!_stores.ContainsKey(typeof(TMessage))) { RegisterMessageType<TMessage>(); }
+            if (!Stores.ContainsKey(typeof(TMessage))) { RegisterMessageType<TMessage>(); }
-            return _stores[typeof(TMessage)] as TypedMessageStore<TMessage>;
+            return Stores[typeof(TMessage)] as TypedMessageStore<TMessage>;
         }
 
-        public void AddMessage<TMessage>(in TMessage message) where TMessage : struct
+        public void AddMessage<TMessage>(TMessage message) where TMessage : struct, IMessage
         {
             Lookup<TMessage>().Add(message);
         }
 
-        public void AddMessage<TMessage>(in TMessage message, double time) where TMessage : struct
+        public void AddMessage<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
             Lookup<TMessage>().Add(message, time);
         }
 
-        public void AddMessageIgnoringTimeDilation<TMessage>(in TMessage message, double time) where TMessage : struct
+        public void AddMessageIgnoringTimeDilation<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
             Lookup<TMessage>().AddIgnoringTimeDilation(message, time);
         }
 
-        public ref readonly TMessage First<TMessage>() where TMessage : struct
+        public TMessage First<TMessage>() where TMessage : struct, IMessage
         {
-            if (!Any<TMessage>()) { throw new NoMessageOfTypeException("No Message of type {0} exists", typeof(TMessage).Name); }
+            return Lookup<TMessage>().First();
-
-            return ref Lookup<TMessage>().First();
         }
 
-        public ReadOnlySpan<TMessage> All<TMessage>() where TMessage : struct
+        public IEnumerable<TMessage> All<TMessage>() where TMessage : struct, IMessage
         {
             return Lookup<TMessage>().All();
         }
 
-        public bool Any<TMessage>() where TMessage : struct
+        public bool Any<TMessage>() where TMessage : struct, IMessage
         {
             return Lookup<TMessage>().Any();
         }
 
-        public IEnumerable<TMessage> WithEntity<TMessage>(int entityID) where TMessage : struct, IHasEntity
+        public IEnumerable<TMessage> WithEntity<TMessage>(int entityID) where TMessage : struct, IMessage, IHasEntity
         {
             return Lookup<TMessage>().WithEntity(entityID);
         }
 
-        public ref readonly TMessage FirstWithEntity<TMessage>(int entityID) where TMessage : struct
+        public bool SomeWithEntity<TMessage>(int entityID) where TMessage : struct, IMessage, IHasEntity
-        {
-            return ref Lookup<TMessage>().FirstWithEntity(entityID);
-        }
-
-        public bool SomeWithEntity<TMessage>(int entityID) where TMessage : struct, IHasEntity
         {
             return Lookup<TMessage>().SomeWithEntity(entityID);
         }
 
         public void ProcessDelayedMessages(double dilatedDelta, double realtimeDelta)
         {
-            foreach (var store in _stores.Values)
+            foreach (var store in Stores.Values)
             {
                 store.ProcessDelayedMessages(dilatedDelta, realtimeDelta);
             }
@@ -76,7 +68,7 @@ namespace Encompass
 
         public void ClearAll()
         {
-            foreach (var store in _stores.Values)
+            foreach (var store in Stores.Values)
             {
                 store.Clear();
             }

encompass-cs/Collections/Replayer.cs

@@ -10,7 +10,7 @@ namespace Encompass
         public abstract void Clear();
     }
 
-    internal class Replayer<TComponent> : Replayer where TComponent : struct
+    internal class Replayer<TComponent> : Replayer where TComponent : struct, IComponent
     {
         private readonly ComponentDeltaStore _deltaStore;
         private readonly HashSet<int> _removals = new HashSet<int>();
@@ -22,10 +22,9 @@ namespace Encompass
 
         public override void Replay(ComponentStore store)
         {
-            foreach (ref readonly var entity in _deltaStore.AllEntities<TComponent>())
+            foreach (var (component, entityID) in _deltaStore.All<TComponent>())
             {
-                ref readonly var component = ref _deltaStore.GetComponent<TComponent>(entity.ID);
+                store.Set(entityID, component);
-                store.Set(entity.ID, component);
             }
 
             foreach (var entityID in _removals)

encompass-cs/Collections/TypedComponentStore.cs

@@ -1,12 +1,12 @@
 using System;
 using System.Collections.Generic;
-using System.Runtime.CompilerServices;
 
 namespace Encompass
 {
     internal abstract class TypedComponentStore
     {
         public abstract int Count { get; }
+        public abstract IEnumerable<(int, Type, IComponent)> AllInterfaceTyped();
         public abstract bool Has(int entity);
         public abstract bool Remove(int entity, int priority);
         public abstract void ForceRemove(int entity);
@@ -14,72 +14,43 @@ namespace Encompass
         public abstract void ClearPriorities();
     }
 
-    internal class TypedComponentStore<TComponent> : TypedComponentStore where TComponent : struct
+    internal class TypedComponentStore<TComponent> : TypedComponentStore where TComponent : struct, IComponent
     {
-        private int _nextID = 0;
+        private readonly Dictionary<int, TComponent> store = new Dictionary<int, TComponent>(128);
-        private readonly Dictionary<int, int> _entityIDToStorageIndex = new Dictionary<int, int>(128);
+        private readonly Dictionary<int, int> priorities = new Dictionary<int, int>(128);
-        private readonly Dictionary<int, int> _priorities = new Dictionary<int, int>(128);
-        private Entity[] _storageIndexToEntities = new Entity[128];
-        private TComponent[] _components = new TComponent[128];
 
-        public override int Count { get => _entityIDToStorageIndex.Count; }
+        public override int Count { get => store.Count; }
 
-        public ref TComponent Get(int entityID)
+        public TComponent Get(int entityID)
         {
-            if (!_entityIDToStorageIndex.ContainsKey(entityID)) { throw new Exceptions.NoComponentOfTypeOnEntityException("No component of type {0} exists on Entity with ID {1}", typeof(TComponent), entityID); }
+            if (!store.ContainsKey(entityID)) { throw new Exceptions.NoComponentOfTypeOnEntityException("No component of type {0} exists on Entity with ID {1}", typeof(TComponent), entityID); }
-            return ref _components[_entityIDToStorageIndex[entityID]];
+            return store[entityID];
         }
 
-        public ref TComponent Singular()
+        public void Set(int entityID, TComponent component)
         {
-            return ref _components[0];
+            store[entityID] = component;
         }
 
-        public ref Entity SingularEntity()
+        public bool Set(int entityID, TComponent component, int priority)
         {
-            return ref _storageIndexToEntities[0];
+            if (!priorities.ContainsKey(entityID) || priority < priorities[entityID])
-        }
-
-        public void Set(int entityID, in TComponent component)
-        {
-            InternalSet(entityID, component);
-        }
-
-        public bool Set(int entityID, in TComponent component, int priority)
-        {
-            if (!_priorities.ContainsKey(entityID) || priority <= _priorities[entityID]) // if priorities are equal that means it's the same engine
             {
-                InternalSet(entityID, component);
+                store[entityID] = component;
-                _priorities[entityID] = priority;
+                priorities[entityID] = priority;
                 return true;
             }
 
             return false;
         }
 
-        private void InternalSet(int entityID, in TComponent component)
-        {
-            if (!_entityIDToStorageIndex.ContainsKey(entityID))
-            {
-                var index = _nextID++;
-                if (index >= _components.Length)
-                {
-                    System.Array.Resize(ref _components, _components.Length * 2);
-                    System.Array.Resize(ref _storageIndexToEntities, _storageIndexToEntities.Length * 2);
-                }
-                _entityIDToStorageIndex[entityID] = index;
-                _storageIndexToEntities[index] = new Entity(entityID);
-            }
-
-            _components[_entityIDToStorageIndex[entityID]] = component;
-        }
-
         public override bool Remove(int entityID, int priority)
         {
-            if (!_priorities.ContainsKey(entityID) || priority <= _priorities[entityID]) // if priorities are equal that means it's the same engine
+            if (!priorities.ContainsKey(entityID) || priority < priorities[entityID])
             {
-                ForceRemove(entityID);
+                priorities[entityID] = priority;
-                _priorities[entityID] = priority;
+                store.Remove(entityID);
+                priorities.Remove(entityID);
                 return true;
             }
 
@@ -88,62 +59,40 @@ namespace Encompass
 
         public override void ForceRemove(int entityID)
         {
-            if (_entityIDToStorageIndex.ContainsKey(entityID))
+            store.Remove(entityID);
-            {
+            priorities.Remove(entityID);
-                var storageIndex = _entityIDToStorageIndex[entityID];
-                _entityIDToStorageIndex.Remove(entityID);
-
-                // move a component into the hole to maintain contiguous memory
-                if (_nextID > 1 && storageIndex != _nextID - 1)
-                {
-                    var lastStorageIndex = _nextID - 1;
-                    ref readonly var lastEntity = ref _storageIndexToEntities[lastStorageIndex];
-
-                    _entityIDToStorageIndex[lastEntity.ID] = storageIndex;
-                    _storageIndexToEntities[storageIndex] = lastEntity;
-                    _components[storageIndex] = _components[lastStorageIndex];
-
-                }
-
-                _nextID--;
-            }
         }
 
         public override bool Has(int entityID)
         {
-            return _entityIDToStorageIndex.ContainsKey(entityID);
+            return store.ContainsKey(entityID);
         }
 
         public override void Clear()
         {
-            _nextID = 0;
+            store.Clear();
-            _entityIDToStorageIndex.Clear();
+            priorities.Clear();
-            _priorities.Clear();
         }
 
         public override void ClearPriorities()
         {
-            _priorities.Clear();
+            priorities.Clear();
         }
 
-        public ReadOnlySpan<Entity> AllEntities()
+        public IEnumerable<(TComponent, int)> All()
         {
-            return new ReadOnlySpan<Entity>(_storageIndexToEntities, 0, _nextID);
+            foreach (var kvp in store)
+            {
+                yield return (kvp.Value, kvp.Key);
+            }
         }
 
-        public IEnumerable<Entity> AllEntitiesAsEnumerable()
+        public override IEnumerable<(int, Type, IComponent)> AllInterfaceTyped()
         {
-            return new ArraySegment<Entity>(_storageIndexToEntities, 0, _nextID);
+            foreach (var kvp in store)
-        }
+            {
-
+                yield return (kvp.Key, typeof(TComponent), (IComponent)kvp.Value);
-        public ReadOnlySpan<TComponent> AllComponents()
+            }
-        {
-            return new ReadOnlySpan<TComponent>(_components, 0, _nextID);
-        }
-
-        public IEnumerable<TComponent> AllComponentsAsEnumerable()
-        {
-            return new ArraySegment<TComponent>(_components, 0, _nextID);
         }
     }
 }

encompass-cs/Collections/TypedMessageStore.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 
 namespace Encompass
@@ -9,119 +8,100 @@ namespace Encompass
         public abstract void Clear();
     }
 
-    internal class TypedMessageStore<TMessage> : TypedMessageStore where TMessage : struct
+    internal class TypedMessageStore<TMessage> : TypedMessageStore where TMessage : struct, IMessage
     {
-        // messages are placed in a contiguous region
+        private readonly List<TMessage> store = new List<TMessage>(128);
-        // so we can return the collection as a Span
+        private readonly List<(TMessage, double)> delayedStore = new List<(TMessage, double)>(128);
-        private int _nextIndex = 0;
+        private readonly List<(TMessage, double)> delayedStoreIgnoringTimeDilation = new List<(TMessage, double)>(128);
-        private TMessage[] _store = new TMessage[128];
+        private readonly Dictionary<int, List<TMessage>> entityToMessage = new Dictionary<int, List<TMessage>>();
-        private readonly List<(TMessage, double)> _delayedStore = new List<(TMessage, double)>(128);
-        private readonly List<(TMessage, double)> _delayedStoreIgnoringTimeDilation = new List<(TMessage, double)>(128);
-        private readonly Dictionary<int, List<int>> _entityToIndices = new Dictionary<int, List<int>>();
 
         public override void ProcessDelayedMessages(double dilatedDelta, double realtimeDelta)
         {
-            for (var i = _delayedStore.Count - 1; i >= 0; i--)
+            for (int i = delayedStore.Count - 1; i >= 0; i--)
             {
-                var (message, time) = _delayedStore[i];
+                var (message, time) = delayedStore[i];
 
                 var updatedTime = time - dilatedDelta;
 
                 if (updatedTime <= 0)
                 {
                     Add(message);
-                    _delayedStore.RemoveAt(i);
+                    delayedStore.RemoveAt(i);
                 }
                 else
                 {
-                    _delayedStore[i] = (message, updatedTime);
+                    delayedStore[i] = (message, updatedTime);
                 }
             }
 
-            for (var i = _delayedStoreIgnoringTimeDilation.Count - 1; i >= 0; i--)
+            for (int i = delayedStoreIgnoringTimeDilation.Count - 1; i >= 0; i--)
             {
-                var (message, time) = _delayedStoreIgnoringTimeDilation[i];
+                var (message, time) = delayedStoreIgnoringTimeDilation[i];
 
                 var updatedTime = time - realtimeDelta;
 
                 if (updatedTime <= 0)
                 {
                     Add(message);
-                    _delayedStoreIgnoringTimeDilation.RemoveAt(i);
+                    delayedStoreIgnoringTimeDilation.RemoveAt(i);
                 }
                 else
                 {
-                    _delayedStoreIgnoringTimeDilation[i] = (message, updatedTime);
+                    delayedStoreIgnoringTimeDilation[i] = (message, updatedTime);
                 }
             }
         }
 
-        public void Add(in TMessage message)
+        public void Add(TMessage message)
         {
-            var index = _nextIndex++;
+            store.Add(message);
-            if (index >= _store.Length)
-            {
-                Array.Resize(ref _store, _store.Length * 2);
-            }
-            _store[index] = message;
             if (message is IHasEntity entityMessage)
             {
                 var entityID = entityMessage.Entity.ID;
-                if (!_entityToIndices.ContainsKey(entityID)) { _entityToIndices.Add(entityID, new List<int>()); }
+                if (!entityToMessage.ContainsKey(entityID)) { entityToMessage.Add(entityID, new List<TMessage>()); }
-                _entityToIndices[entityID].Add(index);
+                entityToMessage[entityID].Add(message);
             }
         }
 
-        public void Add(in TMessage message, double time)
+        public void Add(TMessage message, double time)
         {
-            _delayedStore.Add((message, time));
+            delayedStore.Add((message, time));
         }
 
-        public void AddIgnoringTimeDilation(in TMessage message, double time)
+        public void AddIgnoringTimeDilation(TMessage message, double time)
         {
-            _delayedStoreIgnoringTimeDilation.Add((message, time));
+            delayedStoreIgnoringTimeDilation.Add((message, time));
         }
 
-        public ref readonly TMessage First()
+        public TMessage First()
         {
-            return ref _store[0];
+            return store[0];
         }
 
         public bool Any()
         {
-            return _nextIndex != 0;
+            return store.Count > 0;
         }
 
-        public ReadOnlySpan<TMessage> All()
+        public IEnumerable<TMessage> All()
         {
-            return new ReadOnlySpan<TMessage>(_store, 0, _nextIndex);
+            return store;
         }
 
         public IEnumerable<TMessage> WithEntity(int entityID)
         {
-            if (_entityToIndices.ContainsKey(entityID))
+            return entityToMessage.ContainsKey(entityID) ? entityToMessage[entityID] : System.Linq.Enumerable.Empty<TMessage>();
-            {
-                foreach (var index in _entityToIndices[entityID])
-                {
-                    yield return _store[index];
-                }
-            }
-        }
-
-        public ref readonly TMessage FirstWithEntity(int entityID)
-        {
-            return ref _store[_entityToIndices[entityID][0]];
         }
 
         public bool SomeWithEntity(int entityID)
         {
-            return _entityToIndices.ContainsKey(entityID) && _entityToIndices[entityID].Count > 0;
+            return entityToMessage.ContainsKey(entityID) && entityToMessage[entityID].Count > 0;
         }
 
         public override void Clear()
         {
-            _nextIndex = 0;
+            store.Clear();
-            foreach (var set in _entityToIndices.Values)
+            foreach (var set in entityToMessage.Values)
             {
                 set.Clear();
             }

encompass-cs/ComponentManager.cs

@@ -1,288 +1,272 @@
 using System;
 using System.Collections.Generic;
+using MoonTools.FastCollections;
 
 namespace Encompass
 {
     internal class ComponentManager
     {
-        private readonly ComponentStore _existingComponentStore;
+        private readonly DrawLayerManager drawLayerManager;
-        private readonly ComponentStore _immediateComponentStore;
+
-        private readonly ComponentDeltaStore _replayStore;
+        private readonly ComponentStore existingComponentStore;
-        private readonly ComponentStore _upToDateComponentStore;
+        private readonly ComponentStore immediateComponentStore;
+        private readonly ComponentDeltaStore replayStore;
+        private ComponentStore upToDateComponentStore;
 
         public Dictionary<Type, int> TypeToIndex { get; }
 
-        private readonly HashSet<int> _entitiesMarkedForRemoval = new HashSet<int>();
+        private readonly HashSet<int> entitiesMarkedForRemoval = new HashSet<int>();
 
-        internal ComponentBitSet ImmediateBits { get { return _immediateComponentStore.ComponentBitSet; } }
+        internal ComponentBitSet ImmediateBits { get { return immediateComponentStore.ComponentBitSet; } }
-        internal ComponentBitSet ExistingBits { get { return _existingComponentStore.ComponentBitSet; } }
+        internal ComponentBitSet ExistingBits { get { return existingComponentStore.ComponentBitSet; } }
 
-        public ComponentManager(Dictionary<Type, int> typeToIndex)
+        public ComponentManager(DrawLayerManager drawLayerManager, Dictionary<Type, int> typeToIndex)
         {
-            _existingComponentStore = new ComponentStore(typeToIndex);
+            this.drawLayerManager = drawLayerManager;
-            _immediateComponentStore = new ComponentStore(typeToIndex);
+            existingComponentStore = new ComponentStore(typeToIndex);
-            _replayStore = new ComponentDeltaStore(typeToIndex);
+            immediateComponentStore = new ComponentStore(typeToIndex);
-            _upToDateComponentStore = new ComponentStore(typeToIndex);
+            replayStore = new ComponentDeltaStore(typeToIndex);
+            upToDateComponentStore = new ComponentStore(typeToIndex);
             TypeToIndex = typeToIndex;
         }
 
-        public void RegisterComponentType<TComponent>() where TComponent : struct
+        public void RegisterComponentType<TComponent>() where TComponent : struct, IComponent
         {
-            _existingComponentStore.RegisterComponentType<TComponent>();
+            existingComponentStore.RegisterComponentType<TComponent>();
-            _immediateComponentStore.RegisterComponentType<TComponent>();
+            immediateComponentStore.RegisterComponentType<TComponent>();
-            _replayStore.RegisterComponentType<TComponent>();
+            replayStore.RegisterComponentType<TComponent>();
-            _upToDateComponentStore.RegisterComponentType<TComponent>();
+            upToDateComponentStore.RegisterComponentType<TComponent>();
         }
 
         internal void SetExistingComponentStore(ComponentStore componentStore)
         {
-            _existingComponentStore.SwapWith(componentStore);
+            existingComponentStore.SwapWith(componentStore);
         }
 
         internal void SetUpToDateComponentStore(ComponentStore componentStore)
         {
-            _upToDateComponentStore.SwapWith(componentStore);
+            upToDateComponentStore.SwapWith(componentStore);
+        }
+
+        internal void RegisterDrawableComponent<TComponent>(int entityID, TComponent component, int layer) where TComponent : struct, IComponent
+        {
+            drawLayerManager.RegisterComponentWithLayer(entityID, component, layer);
         }
 
         internal void WriteComponents()
         {
-            _existingComponentStore.UpdateUsing(_replayStore);
+            existingComponentStore.UpdateUsing(replayStore);
-            _existingComponentStore.ClearAllPriorities();
+            existingComponentStore.ClearAllPriorities();
-            _upToDateComponentStore.ClearAllPriorities();
+            upToDateComponentStore.ClearAllPriorities();
-            _immediateComponentStore.ClearAll();
+            immediateComponentStore.ClearAll();
-            _replayStore.ClearAll();
+            replayStore.ClearAll();
         }
 
-        internal bool AddImmediateComponent<TComponent>(int entityID, in TComponent component, int priority) where TComponent : struct
+        internal bool AddImmediateComponent<TComponent>(int entityID, TComponent component, int priority) where TComponent : struct, IComponent
         {
-            if (_immediateComponentStore.Set(entityID, component, priority))
+            if (immediateComponentStore.Set(entityID, component, priority))
             {
-                _replayStore.Set(entityID, component);
+                replayStore.Set(entityID, component);
-                _upToDateComponentStore.Set(entityID, component);
+                upToDateComponentStore.Set(entityID, component);
                 return true;
             }
 
             return false;
         }
 
-        internal void AddImmediateComponent<TComponent>(int entityID, in TComponent component) where TComponent : struct
+        internal void AddImmediateComponent<TComponent>(int entityID, TComponent component) where TComponent : struct, IComponent
         {
-            _immediateComponentStore.Set(entityID, component);
+            immediateComponentStore.Set(entityID, component);
-            _replayStore.Set(entityID, component);
+            replayStore.Set(entityID, component);
-            _upToDateComponentStore.Set(entityID, component);
+            upToDateComponentStore.Set(entityID, component);
         }
 
-        internal bool UpdateComponent<TComponent>(int entityID, in TComponent component, int priority) where TComponent : struct
+        internal bool UpdateComponent<TComponent>(int entityID, TComponent component, int priority) where TComponent : struct, IComponent
         {
-            var result = _upToDateComponentStore.Set(entityID, component, priority);
+            var result = upToDateComponentStore.Set(entityID, component, priority);
             if (result)
             {
-                _replayStore.Set(entityID, component);
+                replayStore.Set(entityID, component);
             }
             return result;
         }
 
-        internal void AddComponent<TComponent>(int entityID, in TComponent component) where TComponent : struct
+        internal void AddComponent<TComponent>(int entityID, TComponent component) where TComponent : struct, IComponent
         {
-            _upToDateComponentStore.Set(entityID, component);
+            upToDateComponentStore.Set(entityID, component);
-            _replayStore.Set(entityID, component);
+            replayStore.Set(entityID, component);
         }
 
         // existing or immediate reads
 
-        internal ReadOnlySpan<TComponent> ReadExistingAndImmediateComponentsByType<TComponent>() where TComponent : struct
+        internal IEnumerable<(TComponent, int)> ReadExistingAndImmediateComponentsByType<TComponent>() where TComponent : struct, IComponent
         {
-            return _upToDateComponentStore.All<TComponent>();
+            return upToDateComponentStore.All<TComponent>();
         }
 
-        internal ref readonly TComponent ExistingOrImmediateSingular<TComponent>() where TComponent : struct
+        internal (TComponent, int) ReadFirstExistingOrImmediateComponentByType<TComponent>() where TComponent : struct, IComponent
         {
-            return ref _upToDateComponentStore.Singular<TComponent>();
+            if (!SomeExistingOrImmediateComponent<TComponent>()) { throw new Exceptions.NoComponentOfTypeException($"No Component with type {typeof(TComponent)} exists"); }
+            var enumerator = ReadExistingAndImmediateComponentsByType<TComponent>().GetEnumerator();
+            enumerator.MoveNext();
+            return enumerator.Current;
         }
 
-        internal ReadOnlySpan<Entity> GetExistingAndImmediateEntities<TComponent>() where TComponent : struct
+        internal bool SomeExistingOrImmediateComponent<TComponent>() where TComponent : struct, IComponent
         {
-            return _upToDateComponentStore.AllEntities<TComponent>();
+            return upToDateComponentStore.Any<TComponent>();
-        }
-
-        internal ref readonly Entity ExistingOrImmediateSingularEntity<TComponent>() where TComponent : struct
-        {
-            return ref _upToDateComponentStore.SingularEntity<TComponent>();
-        }
-
-        internal bool SomeExistingOrImmediateComponent<TComponent>() where TComponent : struct
-        {
-            return _upToDateComponentStore.Any<TComponent>();
         }
 
         // existing reads
 
-        internal ReadOnlySpan<TComponent> GetExistingComponents<TComponent>() where TComponent : struct
+        internal (TComponent, int) ReadFirstExistingComponentByType<TComponent>() where TComponent : struct, IComponent
         {
-            return _existingComponentStore.All<TComponent>();
+            if (!SomeExistingComponent<TComponent>()) { throw new Exceptions.NoComponentOfTypeException($"No Component with type {typeof(TComponent)} exists"); }
+            var enumerator = GetComponentsIncludingEntity<TComponent>().GetEnumerator();
+            enumerator.MoveNext();
+            return enumerator.Current;
         }
 
-        internal ref readonly TComponent ExistingSingular<TComponent>() where TComponent : struct
+        internal bool SomeExistingComponent<TComponent>() where TComponent : struct, IComponent
         {
-            return ref _existingComponentStore.Singular<TComponent>();
+            return existingComponentStore.Any<TComponent>();
-        }
-
-        internal ReadOnlySpan<Entity> GetExistingEntities<TComponent>() where TComponent : struct
-        {
-            return _existingComponentStore.AllEntities<TComponent>();
-        }
-
-        internal IEnumerable<Entity> GetExistingEntitiesAsEnumerable<TComponent>() where TComponent : struct
-        {
-            return _existingComponentStore.AllEntitiesAsEnumerable<TComponent>();
-        }
-
-        internal ref readonly Entity ExistingSingularEntity<TComponent>() where TComponent : struct
-        {
-            return ref _existingComponentStore.SingularEntity<TComponent>();
-        }
-
-        internal bool SomeExistingComponent<TComponent>() where TComponent : struct
-        {
-            return _existingComponentStore.Any<TComponent>();
         }
 
         // immediate reads
 
-        internal ReadOnlySpan<TComponent> ReadImmediateComponentsByType<TComponent>() where TComponent : struct
+        internal IEnumerable<(TComponent, int)> ReadImmediateComponentsByType<TComponent>() where TComponent : struct, IComponent
         {
-            return _immediateComponentStore.All<TComponent>();
+            return immediateComponentStore.All<TComponent>();
         }
 
-        internal ref readonly TComponent ImmediateSingular<TComponent>() where TComponent : struct
+        internal (TComponent, int) ReadFirstImmediateComponentByType<TComponent>() where TComponent : struct, IComponent
         {
-            return ref _immediateComponentStore.Singular<TComponent>();
+            if (!SomeImmediateComponent<TComponent>()) { throw new Exceptions.NoComponentOfTypeException($"No Component with type {typeof(TComponent)} exists"); }
+            var enumerator = ReadImmediateComponentsByType<TComponent>().GetEnumerator();
+            enumerator.MoveNext();
+            return enumerator.Current;
         }
 
-        internal ReadOnlySpan<Entity> GetImmediateEntities<TComponent>() where TComponent : struct
+        internal bool SomeImmediateComponent<TComponent>() where TComponent : struct, IComponent
         {
-            return _immediateComponentStore.AllEntities<TComponent>();
+            return immediateComponentStore.Any<TComponent>();
-        }
-
-        internal ref readonly Entity ImmediateSingularEntity<TComponent>() where TComponent : struct
-        {
-            return ref _immediateComponentStore.SingularEntity<TComponent>();
-        }
-
-        internal bool SomeImmediateComponent<TComponent>() where TComponent : struct
-        {
-            return _immediateComponentStore.Any<TComponent>();
         }
 
         // component getters
 
-        internal ref TComponent ReadImmediateOrExistingComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct
+        internal TComponent ReadImmediateOrExistingComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return ref _upToDateComponentStore.Get<TComponent>(entityID);
+            return upToDateComponentStore.Get<TComponent>(entityID);
         }
 
-        internal ref TComponent ReadExistingComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct
+        internal TComponent ReadExistingComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return ref _existingComponentStore.Get<TComponent>(entityID);
+            return existingComponentStore.Get<TComponent>(entityID);
         }
 
-        internal ref TComponent ReadImmediateComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct
+        internal TComponent ReadImmediateComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return ref _immediateComponentStore.Get<TComponent>(entityID);
+            return immediateComponentStore.Get<TComponent>(entityID);
         }
 
         // has checkers
 
-        internal bool HasExistingOrImmediateComponent<TComponent>(int entityID) where TComponent : struct
+        internal bool HasExistingOrImmediateComponent<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return _upToDateComponentStore.Has<TComponent>(entityID);
+            return upToDateComponentStore.Has<TComponent>(entityID);
         }
 
         internal bool HasExistingOrImmediateComponent(int entityID, Type type)
         {
-            return _upToDateComponentStore.Has(type, entityID);
+            return upToDateComponentStore.Has(type, entityID);
         }
 
-        internal bool HasExistingComponent<TComponent>(int entityID) where TComponent : struct
+        internal bool HasExistingComponent<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return _existingComponentStore.Has<TComponent>(entityID);
+            return existingComponentStore.Has<TComponent>(entityID);
         }
 
         internal bool HasExistingComponent(int entityID, Type type)
         {
-            return _existingComponentStore.Has(type, entityID);
+            return existingComponentStore.Has(type, entityID);
         }
 
-        internal bool HasImmediateComponent<TComponent>(int entityID) where TComponent : struct
+        internal bool HasImmediateComponent<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return _immediateComponentStore.Has<TComponent>(entityID);
+            return immediateComponentStore.Has<TComponent>(entityID);
         }
 
         internal bool HasImmediateComponent(int entityID, Type type)
         {
-            return _immediateComponentStore.Has(type, entityID);
+            return immediateComponentStore.Has(type, entityID);
         }
 
-        internal ReadOnlySpan<TComponent> GetComponentsByType<TComponent>() where TComponent : struct
+        internal IEnumerable<(TComponent, int)> GetComponentsIncludingEntity<TComponent>() where TComponent : struct, IComponent
         {
-            return _existingComponentStore.All<TComponent>();
+            return existingComponentStore.All<TComponent>();
         }
 
-        internal IEnumerable<TComponent> GetComponentsByTypeEnumerable<TComponent>() where TComponent : struct
+        internal IEnumerable<TComponent> GetComponentsByType<TComponent>() where TComponent : struct, IComponent
         {
-            return _existingComponentStore.AllAsEnumerable<TComponent>();
+            foreach (var pair in existingComponentStore.All<TComponent>())
+            {
+                yield return pair.Item1;
+            }
         }
 
-        internal ref readonly TComponent GetComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct
+        internal TComponent GetComponentByEntityAndType<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return ref _existingComponentStore.Get<TComponent>(entityID);
+            return existingComponentStore.Get<TComponent>(entityID);
         }
 
-        internal bool EntityHasComponentOfType<TComponent>(int entityID) where TComponent : struct
+        internal bool EntityHasComponentOfType<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            return _existingComponentStore.Has<TComponent>(entityID);
+            return existingComponentStore.Has<TComponent>(entityID);
         }
 
         internal void MarkAllComponentsOnEntityForRemoval(int entityID)
         {
-            _entitiesMarkedForRemoval.Add(entityID);
+            entitiesMarkedForRemoval.Add(entityID);
         }
 
         internal void RemoveMarkedComponents()
         {
-            foreach (var entityID in _entitiesMarkedForRemoval)
+            foreach (var entityID in entitiesMarkedForRemoval)
             {
-                _existingComponentStore.Remove(entityID);
+                existingComponentStore.Remove(entityID);
-                _immediateComponentStore.Remove(entityID);
+                immediateComponentStore.Remove(entityID);
-                _replayStore.Remove(entityID);
+                replayStore.Remove(entityID);
-                _upToDateComponentStore.Remove(entityID);
+                upToDateComponentStore.Remove(entityID);
+                drawLayerManager.UnRegisterEntityWithLayer(entityID);
             }
 
-            _entitiesMarkedForRemoval.Clear();
+            entitiesMarkedForRemoval.Clear();
         }
 
-        public bool RemoveImmediate<TComponent>(int entityID, int priority) where TComponent : struct
+        public bool RemoveImmediate<TComponent>(int entityID, int priority) where TComponent : struct, IComponent
         {
-            if (_immediateComponentStore.Remove<TComponent>(entityID, priority))
+            if (immediateComponentStore.Remove<TComponent>(entityID, priority))
             {
-                _replayStore.Remove<TComponent>(entityID, priority);
+                replayStore.Remove<TComponent>(entityID, priority);
-                _upToDateComponentStore.Remove<TComponent>(entityID, priority);
+                upToDateComponentStore.Remove<TComponent>(entityID, priority);
+                drawLayerManager.UnRegisterComponentWithLayer<TComponent>(entityID);
                 return true;
             }
             return false;
         }
 
-        public void Remove<TComponent>(int entityID, int priority) where TComponent : struct
+        public void Remove<TComponent>(int entityID, int priority) where TComponent : struct, IComponent
         {
-            if (_upToDateComponentStore.Remove<TComponent>(entityID, priority))
+            if (upToDateComponentStore.Remove<TComponent>(entityID, priority))
             {
-                _replayStore.Remove<TComponent>(entityID, priority);
+                replayStore.Remove<TComponent>(entityID, priority);
+                drawLayerManager.UnRegisterComponentWithLayer<TComponent>(entityID);
             }
         }
 
         public bool UpToDateEntityIsEmpty(int entityID)
         {
-            return _upToDateComponentStore.EntityBitArray(entityID).AllFalse();
+            return upToDateComponentStore.EntityBitArray(entityID).AllFalse();
         }
     }
 }

encompass-cs/DrawLayerManager.cs

@@ -0,0 +1,118 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
+
+namespace Encompass
+{
+    internal class DrawLayerManager
+    {
+        private readonly SortedList<int, int> layerOrder = new SortedList<int, int>();
+
+        private readonly Dictionary<int, ComponentStore> layerIndexToComponentStore = new Dictionary<int, ComponentStore>(512);
+        private readonly Dictionary<int, HashSet<GeneralRenderer>> layerIndexToGeneralRenderers = new Dictionary<int, HashSet<GeneralRenderer>>(512);
+
+        private readonly Dictionary<Type, Dictionary<int, int>> typeToEntityToLayer = new Dictionary<Type, Dictionary<int, int>>(512);
+        private Dictionary<Type, int> typeToIndex;
+        public IEnumerable<int> LayerOrder { get { return layerOrder.Values; } }
+
+        public DrawLayerManager(Dictionary<Type, int> typeToIndex)
+        {
+            this.typeToIndex = typeToIndex;
+            RegisterDrawLayer(0);
+        }
+
+        public void RegisterDrawLayer(int layer)
+        {
+            if (!layerIndexToComponentStore.ContainsKey(layer))
+            {
+                layerOrder.Add(layer, layer);
+                layerIndexToGeneralRenderers.Add(layer, new HashSet<GeneralRenderer>());
+                layerIndexToComponentStore.Add(layer, new ComponentStore(typeToIndex));
+            }
+        }
+
+        public void RegisterOrderedDrawable<TComponent>() where TComponent : struct, IComponent
+        {
+            if (!typeToEntityToLayer.ContainsKey(typeof(TComponent)))
+            {
+                typeToEntityToLayer.Add(typeof(TComponent), new Dictionary<int, int>(128));
+            }
+
+            foreach (var pair in layerIndexToComponentStore)
+            {
+                pair.Value.RegisterComponentType<TComponent>();
+            }
+        }
+
+        public void RegisterGeneralRendererWithLayer(GeneralRenderer renderer, int layer)
+        {
+            RegisterDrawLayer(layer);
+            var set = layerIndexToGeneralRenderers[layer];
+            set.Add(renderer);
+        }
+
+        public void UnregisterGeneralRendererWithLayer(GeneralRenderer renderer, int layer)
+        {
+            if (layerIndexToGeneralRenderers.ContainsKey(layer))
+            {
+                layerIndexToGeneralRenderers[layer].Remove(renderer);
+            }
+        }
+
+        public void AdjustRendererLayer(GeneralRenderer renderer, int oldLayer, int newLayer)
+        {
+            UnregisterGeneralRendererWithLayer(renderer, oldLayer);
+            RegisterGeneralRendererWithLayer(renderer, newLayer);
+        }
+
+        public void RegisterComponentWithLayer<TComponent>(int entityID, TComponent component, int layer) where TComponent : struct, IComponent
+        {
+            if (!layerIndexToComponentStore.ContainsKey(layer))
+            {
+                throw new UndefinedLayerException("Layer {0} is not defined. Use WorldBuilder.RegisterDrawLayer to register the layer.", layer);
+            }
+
+            if (typeToEntityToLayer[typeof(TComponent)].ContainsKey(entityID)) { UnRegisterComponentWithLayer<TComponent>(entityID); }
+
+            var set = layerIndexToComponentStore[layer];
+            set.Set<TComponent>(entityID, component);
+
+            typeToEntityToLayer[typeof(TComponent)].Add(entityID, layer);
+        }
+
+        public void UnRegisterComponentWithLayer<TComponent>(int entityID) where TComponent : struct, IComponent
+        {
+            if (!typeToEntityToLayer.ContainsKey(typeof(TComponent))) { return; }
+
+            if (typeToEntityToLayer[typeof(TComponent)].ContainsKey(entityID))
+            {
+                var layer = typeToEntityToLayer[typeof(TComponent)][entityID];
+                layerIndexToComponentStore[layer].ForceRemove<TComponent>(entityID);
+            }
+            typeToEntityToLayer[typeof(TComponent)].Remove(entityID);
+        }
+
+        public void UnRegisterEntityWithLayer(int entityID)
+        {
+            foreach (var store in layerIndexToComponentStore.Values)
+            {
+                store.Remove(entityID);
+            }
+        }
+
+        public IEnumerable<GeneralRenderer> GeneralRenderersByLayer(int layer)
+        {
+            return layerIndexToGeneralRenderers.ContainsKey(layer) ?
+                layerIndexToGeneralRenderers[layer] :
+                Enumerable.Empty<GeneralRenderer>();
+        }
+
+        public IEnumerable<(int, Type, IComponent)> AllInLayer(int layer)
+        {
+            return layerIndexToComponentStore.ContainsKey(layer) ?
+                layerIndexToComponentStore[layer].AllInterfaceTyped() :
+                Enumerable.Empty<(int, Type, IComponent)>();
+        }
+    }
+}

encompass-cs/Engine.cs

@@ -3,6 +3,7 @@ using System.Reflection;
 using System.Collections.Generic;
 using System.Linq;
 using Encompass.Exceptions;
+using MoonTools.FastCollections;
 
 namespace Encompass
 {
@@ -13,121 +14,104 @@ namespace Encompass
     /// </summary>
     public abstract class Engine : IEquatable<Engine>
     {
-        internal Guid _id;
+        internal Guid ID;
 
-        internal readonly HashSet<Type> ReadTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> readTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> ReadImmediateTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> readImmediateTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> SendTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> sendTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> ReceiveTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> receiveTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> WriteTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> writeTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> WriteImmediateTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> writeImmediateTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> QueryWithTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> queryWithTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> QueryWithoutTypes = new HashSet<Type>();
+        internal readonly HashSet<Type> queryWithoutTypes = new HashSet<Type>();
-        internal readonly HashSet<Type> AddTypes = new HashSet<Type>();
+        internal readonly Dictionary<Type, int> writePriorities = new Dictionary<Type, int>();
-        internal readonly Dictionary<Type, int> WritePriorities = new Dictionary<Type, int>();
+        internal readonly int defaultWritePriority = 0;
-        internal readonly int DefaultWritePriority = 0;
 
         /// <summary>
         /// If false, the Engine will ignore time dilation.
         /// </summary>
-        internal bool _usesTimeDilation = true;
+        internal bool usesTimeDilation = true;
-        public bool TimeDilationActive { get => _usesTimeDilation && _timeManager.TimeDilationActive; }
+        public bool TimeDilationActive { get => usesTimeDilation && timeManager.TimeDilationActive; }
 
-        private EntityManager _entityManager;
+        private EntityManager entityManager;
-        private MessageManager _messageManager;
+        private MessageManager messageManager;
-        private ComponentManager _componentManager;
+        private ComponentManager componentManager;
-        private TimeManager _timeManager;
+        private TimeManager timeManager;
-        private TrackingManager _trackingManager;
+        private TrackingManager trackingManager;
 
-        private EntitySetQuery _entityQuery;
+        private EntitySetQuery entityQuery;
 
-        private readonly HashSet<int> _trackedEntities = new HashSet<int>();
+        private HashSet<int> _trackedEntities = new HashSet<int>();
         protected IEnumerable<Entity> TrackedEntities
         {
             get
             {
                 foreach (var entityID in _trackedEntities)
                 {
-                    yield return _entityManager.GetEntity(entityID);
+                    yield return entityManager.GetEntity(entityID);
                 }
             }
         }
 
-        private readonly HashSet<int> _newlyCreatedEntities = new HashSet<int>();
+        private HashSet<int> _newlyCreatedEntities = new HashSet<int>();
 
         protected Engine()
         {
-            _id = Guid.NewGuid();
+            ID = Guid.NewGuid();
-
-            var addsAttribute = GetType().GetCustomAttribute<Adds>(false);
-            if (addsAttribute != null)
-            {
-                AddTypes = addsAttribute.addTypes;
-            }
 
             var sendsAttribute = GetType().GetCustomAttribute<Sends>(false);
             if (sendsAttribute != null)
             {
-                SendTypes = sendsAttribute.SendTypes;
+                sendTypes = sendsAttribute.sendTypes;
             }
 
             var activatesAttribute = GetType().GetCustomAttribute<WritesImmediate>(false);
             if (activatesAttribute != null)
             {
-                WriteImmediateTypes = activatesAttribute.WriteImmediateTypes;
+                writeImmediateTypes = activatesAttribute.writeImmediateTypes;
             }
 
             var defaultWritePriorityAttribute = GetType().GetCustomAttribute<DefaultWritePriority>(false);
 
             if (defaultWritePriorityAttribute != null)
             {
-                DefaultWritePriority = defaultWritePriorityAttribute.WritePriority;
+                defaultWritePriority = defaultWritePriorityAttribute.writePriority;
             }
 
             foreach (var writesAttribute in GetType().GetCustomAttributes<Writes>(false))
             {
-                WriteTypes.UnionWith(writesAttribute.WriteTypes);
+                writeTypes.UnionWith(writesAttribute.writeTypes);
-                WritePriorities = new Dictionary<Type, int>[2] { WritePriorities, writesAttribute.Priorities }.SelectMany(dict => dict).ToDictionary(pair => pair.Key, pair => pair.Value);
+                writePriorities = new Dictionary<Type, int>[2] { writePriorities, writesAttribute.priorities }.SelectMany(dict => dict).ToDictionary(pair => pair.Key, pair => pair.Value);
             }
 
             var receivesAttribute = GetType().GetCustomAttribute<Receives>(false);
             if (receivesAttribute != null)
             {
-                ReceiveTypes = receivesAttribute.ReceiveTypes;
+                receiveTypes = receivesAttribute.receiveTypes;
             }
 
             var readsAttribute = GetType().GetCustomAttribute<Reads>(false);
             if (readsAttribute != null)
             {
-                ReadTypes = readsAttribute.ReadTypes;
+                readTypes = readsAttribute.readTypes;
             }
 
             var readsImmediateAttribute = GetType().GetCustomAttribute<ReadsImmediate>(false);
             if (readsImmediateAttribute != null)
             {
-                ReadImmediateTypes = readsImmediateAttribute.ReadImmediateTypes;
+                readImmediateTypes = readsImmediateAttribute.readImmediateTypes;
             }
 
             var queryWithAttribute = GetType().GetCustomAttribute<QueryWith>(false);
             if (queryWithAttribute != null)
             {
-                QueryWithTypes = queryWithAttribute.QueryWithTypes;
+                queryWithTypes = queryWithAttribute.queryWithTypes;
-            }
-
-            foreach (var queryType in QueryWithTypes)
-            {
-                ReadTypes.Add(queryType);
             }
 
             var queryWithoutAttribute = GetType().GetCustomAttribute<QueryWithout>(false);
             if (queryWithoutAttribute != null)
             {
-                QueryWithoutTypes = queryWithoutAttribute.QueryWithoutTypes;
+                queryWithoutTypes = queryWithoutAttribute.queryWithoutTypes;
-            }
-
-            foreach (var queryType in QueryWithoutTypes)
-            {
-                ReadTypes.Add(queryType);
             }
         }
 
@@ -143,42 +127,42 @@ namespace Encompass
 
         public bool Equals(Engine other)
         {
-            return other._id == _id;
+            return other.ID == ID;
         }
 
         public override int GetHashCode()
         {
-            return HashCode.Combine(_id);
+            return ID.GetHashCode();
         }
 
         internal void AssignEntityManager(EntityManager entityManager)
         {
-            _entityManager = entityManager;
+            this.entityManager = entityManager;
         }
 
         internal void AssignComponentManager(ComponentManager componentManager)
         {
-            _componentManager = componentManager;
+            this.componentManager = componentManager;
         }
 
         internal void AssignMessageManager(MessageManager messageManager)
         {
-            _messageManager = messageManager;
+            this.messageManager = messageManager;
         }
 
         internal void AssignTimeManager(TimeManager timeManager)
         {
-            _timeManager = timeManager;
+            this.timeManager = timeManager;
         }
 
         internal void AssignTrackingManager(TrackingManager trackingManager)
         {
-            _trackingManager = trackingManager;
+            this.trackingManager = trackingManager;
         }
 
-        internal void CheckMessageRead<TMessage>() where TMessage : struct
+        internal void CheckMessageRead<TMessage>() where TMessage : struct, IMessage
         {
-            if (!ReceiveTypes.Contains(typeof(TMessage)))
+            if (!receiveTypes.Contains(typeof(TMessage)))
             {
                 throw new IllegalReadException("Engine {0} tried to read undeclared Message {1}", this.GetType().Name, typeof(TMessage).Name);
             }
@@ -205,7 +189,7 @@ namespace Encompass
         /// </summary>
         protected Entity CreateEntity()
         {
-            var entity = _entityManager.CreateEntity();
+            var entity = entityManager.CreateEntity();
             _newlyCreatedEntities.Add(entity.ID);
             return entity;
         }
@@ -213,9 +197,9 @@ namespace Encompass
         /// <summary>
         /// Returns true if an Entity with the specified ID exists.
         /// </summary>
-        protected bool EntityExists(in Entity entity)
+        protected bool EntityExists(Entity entity)
         {
-            return _entityManager.EntityExists(entity.ID);
+            return entityManager.EntityExists(entity.ID);
         }
 
         /// <summary>
@@ -223,52 +207,50 @@ namespace Encompass
         /// </summary>
         protected bool EntityExists(int entityID)
         {
-            return _entityManager.EntityExists(entityID);
+            return entityManager.EntityExists(entityID);
-        }
-
-        /// <summary>
-        /// Returns all Entities containing the specified Component type.
-        /// </summary>
-        protected ReadOnlySpan<Entity> ReadEntities<TComponent>() where TComponent : struct
-        {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
-            if (existingRead && immediateRead)
-            {
-                return _componentManager.GetExistingAndImmediateEntities<TComponent>();
-            }
-            else if (existingRead)
-            {
-                return _componentManager.GetExistingEntities<TComponent>();
-            }
-            else if (immediateRead)
-            {
-                return _componentManager.GetImmediateEntities<TComponent>();
-            }
-            else
-            {
-                throw new IllegalReadException("Engine {0} tried to read undeclared Component {1}", GetType().Name, typeof(TComponent).Name);
-            }
         }
 
         /// <summary>
         /// Returns an Entity containing the specified Component type.
         /// </summary>
-        protected ref readonly Entity ReadEntity<TComponent>() where TComponent : struct
+        protected Entity ReadEntity<TComponent>() where TComponent : struct, IComponent
         {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
+            return entityManager.GetEntity(ReadComponentHelper<TComponent>().Item2);
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
+        }
+
+        /// <summary>
+        /// Returns all Entities containing the specified Component type.
+        /// </summary>
+        protected IEnumerable<Entity> ReadEntities<TComponent>() where TComponent : struct, IComponent
+        {
+            foreach (var pair in ReadComponentsHelper<TComponent>())
+            {
+                yield return entityManager.GetEntity(pair.Item2);
+            }
+        }
+
+        // these next two are for the ComponentMessageEmitter only
+
+        internal IEnumerable<TComponent> ReadComponentsFromWorld<TComponent>() where TComponent : struct, IComponent
+        {
+            return componentManager.GetComponentsByType<TComponent>();
+        }
+
+        private IEnumerable<(TComponent, int)> ReadComponentsHelper<TComponent>() where TComponent : struct, IComponent
+        {
+            var immediateRead = readImmediateTypes.Contains(typeof(TComponent));
+            var existingRead = readTypes.Contains(typeof(TComponent));
             if (existingRead && immediateRead)
             {
-                return ref _componentManager.ExistingOrImmediateSingularEntity<TComponent>();
+                return componentManager.ReadExistingAndImmediateComponentsByType<TComponent>();
             }
             else if (existingRead)
             {
-                return ref _componentManager.ExistingSingularEntity<TComponent>();
+                return componentManager.GetComponentsIncludingEntity<TComponent>();
             }
             else if (immediateRead)
             {
-                return ref _componentManager.ImmediateSingularEntity<TComponent>();
+                return componentManager.ReadImmediateComponentsByType<TComponent>();
             }
             else
             {
@@ -279,21 +261,40 @@ namespace Encompass
         /// <summary>
         /// Returns all of the Components with the specified Component Type.
         /// </summary>
-        protected ReadOnlySpan<TComponent> ReadComponents<TComponent>() where TComponent : struct
+        protected IEnumerable<TComponent> ReadComponents<TComponent>() where TComponent : struct, IComponent
         {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
+            foreach (var pair in ReadComponentsHelper<TComponent>())
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
+            {
+                yield return pair.Item1;
+            }
+        }
+
+        /// <summary>
+        /// Returns all of the components of the specified type including an Entity reference for each Component.
+        /// </summary>
+        protected IEnumerable<(TComponent, Entity)> ReadComponentsIncludingEntity<TComponent>() where TComponent : struct, IComponent
+        {
+            foreach (var (component, id) in ReadComponentsHelper<TComponent>())
+            {
+                yield return (component, entityManager.GetEntity(id));
+            }
+        }
+
+        private (TComponent, int) ReadComponentHelper<TComponent>() where TComponent : struct, IComponent
+        {
+            var immediateRead = readImmediateTypes.Contains(typeof(TComponent));
+            var existingRead = readTypes.Contains(typeof(TComponent));
             if (existingRead && immediateRead)
             {
-                return _componentManager.ReadExistingAndImmediateComponentsByType<TComponent>();
+                return componentManager.ReadFirstExistingOrImmediateComponentByType<TComponent>();
             }
             else if (existingRead)
             {
-                return _componentManager.GetExistingComponents<TComponent>();
+                return componentManager.ReadFirstExistingComponentByType<TComponent>();
             }
             else if (immediateRead)
             {
-                return _componentManager.ReadImmediateComponentsByType<TComponent>();
+                return componentManager.ReadFirstImmediateComponentByType<TComponent>();
             }
             else
             {
@@ -304,46 +305,38 @@ namespace Encompass
         /// <summary>
         /// Returns a Component with the specified Component Type. If multiples exist, an arbitrary Component is returned.
         /// </summary>
-        protected ref readonly TComponent ReadComponent<TComponent>() where TComponent : struct
+        protected TComponent ReadComponent<TComponent>() where TComponent : struct, IComponent
         {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
+            return ReadComponentHelper<TComponent>().Item1;
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
+        }
-            if (existingRead && immediateRead)
+
-            {
+        /// <summary>
-                return ref _componentManager.ExistingOrImmediateSingular<TComponent>();
+        /// Returns a component of the specified type including its Entity reference. If multiples exist, an arbitrary Component is returned.
-            }
+        /// </summary>
-            else if (existingRead)
+        protected (TComponent, Entity) ReadComponentIncludingEntity<TComponent>() where TComponent : struct, IComponent
-            {
+        {
-                return ref _componentManager.ExistingSingular<TComponent>();
+            var (component, id) = ReadComponentHelper<TComponent>();
-            }
+            return (component, entityManager.GetEntity(id));
-            else if (immediateRead)
-            {
-                return ref _componentManager.ImmediateSingular<TComponent>();
-            }
-            else
-            {
-                throw new IllegalReadException("Engine {0} tried to read undeclared Component {1}", GetType().Name, typeof(TComponent).Name);
-            }
         }
 
         /// <summary>
         /// Returns true if any Component with the specified Component Type exists.
         /// </summary>
-        protected bool SomeComponent<TComponent>() where TComponent : struct
+        protected bool SomeComponent<TComponent>() where TComponent : struct, IComponent
         {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
+            var immediateRead = readImmediateTypes.Contains(typeof(TComponent));
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
+            var existingRead = readTypes.Contains(typeof(TComponent));
             if (existingRead && immediateRead)
             {
-                return _componentManager.SomeExistingOrImmediateComponent<TComponent>();
+                return componentManager.SomeExistingOrImmediateComponent<TComponent>();
             }
             else if (existingRead)
             {
-                return _componentManager.SomeExistingComponent<TComponent>();
+                return componentManager.SomeExistingComponent<TComponent>();
             }
             else if (immediateRead)
             {
-                return _componentManager.SomeImmediateComponent<TComponent>();
+                return componentManager.SomeImmediateComponent<TComponent>();
             }
             else
             {
@@ -351,21 +344,21 @@ namespace Encompass
             }
         }
 
-        private ref TComponent GetComponentHelper<TComponent>(int entityID) where TComponent : struct
+        private TComponent GetComponentHelper<TComponent>(int entityID) where TComponent : struct, IComponent
         {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
+            var immediateRead = readImmediateTypes.Contains(typeof(TComponent));
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
+            var existingRead = readTypes.Contains(typeof(TComponent));
             if (existingRead && immediateRead)
             {
-                return ref _componentManager.ReadImmediateOrExistingComponentByEntityAndType<TComponent>(entityID);
+                return componentManager.ReadImmediateOrExistingComponentByEntityAndType<TComponent>(entityID);
             }
             else if (existingRead)
             {
-                return ref _componentManager.ReadExistingComponentByEntityAndType<TComponent>(entityID);
+                return componentManager.ReadExistingComponentByEntityAndType<TComponent>(entityID);
             }
             else if (immediateRead)
             {
-                return ref _componentManager.ReadImmediateComponentByEntityAndType<TComponent>(entityID);
+                return componentManager.ReadImmediateComponentByEntityAndType<TComponent>(entityID);
             }
             else
             {
@@ -382,9 +375,9 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalReadException">
         /// Thrown when the Engine does not declare that it reads the given Component Type.
         /// </exception>
-        protected ref readonly TComponent GetComponent<TComponent>(in Entity entity) where TComponent : struct
+        protected TComponent GetComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
         {
-            return ref GetComponentHelper<TComponent>(entity.ID);
+            return GetComponentHelper<TComponent>(entity.ID);
         }
 
         /// <summary>
@@ -393,22 +386,22 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalReadException">
         /// Thrown when the Engine does not declare that is Reads the given Component Type.
         /// </exception>
-        protected bool HasComponent<TComponent>(in Entity entity) where TComponent : struct
+        protected bool HasComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
         {
-            var immediateRead = ReadImmediateTypes.Contains(typeof(TComponent));
+            var immediateRead = readImmediateTypes.Contains(typeof(TComponent));
-            var existingRead = ReadTypes.Contains(typeof(TComponent));
+            var existingRead = readTypes.Contains(typeof(TComponent));
 
             if (immediateRead && existingRead)
             {
-                return _componentManager.HasExistingOrImmediateComponent<TComponent>(entity.ID);
+                return componentManager.HasExistingOrImmediateComponent<TComponent>(entity.ID);
             }
             else if (existingRead)
             {
-                return _componentManager.HasExistingComponent<TComponent>(entity.ID);
+                return componentManager.HasExistingComponent<TComponent>(entity.ID);
             }
             else if (immediateRead)
             {
-                return _componentManager.HasImmediateComponent<TComponent>(entity.ID);
+                return componentManager.HasImmediateComponent<TComponent>(entity.ID);
             }
             else
             {
@@ -422,22 +415,22 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalReadException">
         /// Thrown when the Engine does not declare that is Reads the given Component Type.
         /// </exception>
-        protected bool HasComponent(in Entity entity, Type type)
+        protected bool HasComponent(Entity entity, Type type)
         {
-            var immediateRead = ReadImmediateTypes.Contains(type);
+            var immediateRead = readImmediateTypes.Contains(type);
-            var existingRead = ReadTypes.Contains(type);
+            var existingRead = readTypes.Contains(type);
 
             if (immediateRead && existingRead)
             {
-                return _componentManager.HasExistingOrImmediateComponent(entity.ID, type);
+                return componentManager.HasExistingOrImmediateComponent(entity.ID, type);
             }
             else if (existingRead)
             {
-                return _componentManager.HasExistingComponent(entity.ID, type);
+                return componentManager.HasExistingComponent(entity.ID, type);
             }
             else if (immediateRead)
             {
-                return _componentManager.HasImmediateComponent(entity.ID, type);
+                return componentManager.HasImmediateComponent(entity.ID, type);
             }
             else
             {
@@ -451,32 +444,37 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalWriteException">
         /// Thrown when the Engine does not declare that it Writes the given Component Type.
         /// </exception>
-        protected void SetComponent<TComponent>(in Entity entity, in TComponent component) where TComponent : struct
+        protected void SetComponent<TComponent>(Entity entity, TComponent component) where TComponent : struct, IComponent
         {
-            var priority = WritePriorities.ContainsKey(typeof(TComponent)) ? WritePriorities[typeof(TComponent)] : DefaultWritePriority;
+            var priority = writePriorities.ContainsKey(typeof(TComponent)) ? writePriorities[typeof(TComponent)] : defaultWritePriority;
 
-            if (!WriteTypes.Contains(typeof(TComponent)))
+            if (!writeTypes.Contains(typeof(TComponent)))
             {
                 throw new IllegalWriteException("Engine {0} tried to update undeclared Component {1}", GetType().Name, typeof(TComponent).Name);
             }
 
             bool written;
-            if (WriteImmediateTypes.Contains(typeof(TComponent)))
+            if (writeImmediateTypes.Contains(typeof(TComponent)))
             {
-                written = _componentManager.AddImmediateComponent(entity.ID, component, priority);
+                written = componentManager.AddImmediateComponent(entity.ID, component, priority);
                 if (written)
                 {
-                    _trackingManager.ImmediateUpdateTracking(entity.ID, typeof(TComponent));
+                    trackingManager.ImmediateUpdateTracking(entity.ID, typeof(TComponent));
                 }
             }
             else
             {
-                written = _componentManager.UpdateComponent(entity.ID, component, priority);
+                written = componentManager.UpdateComponent(entity.ID, component, priority);
             }
 
-            if (!_componentManager.HasExistingComponent<TComponent>(entity.ID))
+            if (!componentManager.HasExistingComponent<TComponent>(entity.ID))
             {
-                _trackingManager.RegisterAddition(entity.ID, typeof(TComponent));
+                trackingManager.RegisterAddition(entity.ID, typeof(TComponent));
+            }
+
+            if (written && component is IDrawableComponent drawableComponent)
+            {
+                componentManager.RegisterDrawableComponent(entity.ID, component, drawableComponent.Layer);
             }
         }
 
@@ -486,29 +484,29 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalWriteException">
         /// Thrown when the Engine does not declare that it Writes the given Component Type.
         /// </exception>
-        protected void AddComponent<TComponent>(in Entity entity, in TComponent component) where TComponent : struct
+        protected void AddComponent<TComponent>(Entity entity, TComponent component) where TComponent : struct, IComponent
         {
-            if (!AddTypes.Contains(typeof(TComponent)))
-            {
-                throw new IllegalWriteException("Engine {0} tried to add undeclared Component {1}", GetType().Name, typeof(TComponent).Name);
-            }
-
             if (!EntityCreatedThisFrame(entity.ID))
             {
                 throw new IllegalWriteException("AddComponent used on Entity that was not created in this context. Use SetComponent instead.");
             }
 
-            if (WriteImmediateTypes.Contains(typeof(TComponent)))
+            if (writeImmediateTypes.Contains(typeof(TComponent)))
             {
-                _componentManager.AddImmediateComponent(entity.ID, component);
+                componentManager.AddImmediateComponent(entity.ID, component);
-                _trackingManager.ImmediateUpdateTracking(entity.ID, typeof(TComponent));
+                trackingManager.ImmediateUpdateTracking(entity.ID, typeof(TComponent));
             }
             else
             {
-                _componentManager.AddComponent(entity.ID, component);
+                componentManager.AddComponent(entity.ID, component);
             }
 
-            _trackingManager.RegisterAddition(entity.ID, typeof(TComponent));
+            trackingManager.RegisterAddition(entity.ID, typeof(TComponent));
+
+            if (component is IDrawableComponent drawableComponent)
+            {
+                componentManager.RegisterDrawableComponent(entity.ID, component, drawableComponent.Layer);
+            }
         }
 
         /// <summary>
@@ -517,32 +515,32 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalSendException">
         /// Thrown when the Engine does not declare that it Sends the Message Type.
         /// </exception>
-        protected void SendMessage<TMessage>(in TMessage message) where TMessage : struct
+        protected void SendMessage<TMessage>(TMessage message) where TMessage : struct, IMessage
         {
-            if (!SendTypes.Contains(typeof(TMessage)))
+            if (!sendTypes.Contains(typeof(TMessage)))
             {
                 throw new IllegalSendException("Engine {0} tried to send undeclared Message {1}", GetType().Name, typeof(TMessage).Name);
             }
 
-            _messageManager.AddMessage(message);
+            messageManager.AddMessage(message);
         }
 
         /// <summary>
         /// Sends a message after the specified number of seconds, respecting time dilation.
         /// </summary>
         /// <param name="time">The time in seconds that will elapse before the message is sent.</param>
-        protected void SendMessage<TMessage>(in TMessage message, double time) where TMessage : struct
+        protected void SendMessage<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
-            _messageManager.AddMessage(message, time);
+            messageManager.AddMessage(message, time);
         }
 
         /// <summary>
         /// Sends a message after the specified number of seconds, ignoring time dilation.
         /// </summary>
         /// <param name="time">The time in seconds that will elapse before the message is sent.</param>
-        protected void SendMessageIgnoringTimeDilation<TMessage>(in TMessage message, double time) where TMessage : struct
+        protected void SendMessageIgnoringTimeDilation<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
-            _messageManager.AddMessageIgnoringTimeDilation(message, time);
+            messageManager.AddMessageIgnoringTimeDilation(message, time);
         }
 
         /// <summary>
@@ -551,10 +549,10 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalReadException">
         /// Thrown when the Engine does not declare that it Receives the specified Message Type.
         /// </exception>
-        protected ReadOnlySpan<TMessage> ReadMessages<TMessage>() where TMessage : struct
+        protected IEnumerable<TMessage> ReadMessages<TMessage>() where TMessage : struct, IMessage
         {
             CheckMessageRead<TMessage>();
-            return _messageManager.GetMessagesByType<TMessage>();
+            return messageManager.GetMessagesByType<TMessage>();
         }
 
         /// <summary>
@@ -563,10 +561,10 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalReadException">
         /// Thrown when the Engine does not declare that it Receives the specified Message Type.
         /// </exception>
-        protected ref readonly TMessage ReadMessage<TMessage>() where TMessage : struct
+        protected TMessage ReadMessage<TMessage>() where TMessage : struct, IMessage
         {
             CheckMessageRead<TMessage>();
-            return ref _messageManager.First<TMessage>();
+            return messageManager.First<TMessage>();
         }
 
         /// <summary>
@@ -575,26 +573,26 @@ namespace Encompass
         /// <exception cref="Encompass.Exceptions.IllegalReadException">
         /// Thrown when the Engine does not declare that it Receives the specified Message Type.
         /// </exception>
-        protected bool SomeMessage<TMessage>() where TMessage : struct
+        protected bool SomeMessage<TMessage>() where TMessage : struct, IMessage
         {
             CheckMessageRead<TMessage>();
-            return _messageManager.Any<TMessage>();
+            return messageManager.Any<TMessage>();
         }
 
         /// <summary>
         /// Destroys the specified Entity. This also removes all of the Components associated with the Entity.
         /// Entity destruction takes place after all the Engines have been processed by World Update.
         /// </summary>
-        protected void Destroy(in Entity entity)
+        protected void Destroy(Entity entity)
         {
-            _entityManager.MarkForDestroy(entity.ID);
+            entityManager.MarkForDestroy(entity.ID);
         }
 
         /// <summary>
         /// Destroys an arbitrary Entity containing a Component of the specified Type.
         /// Entity destruction takes place after all the Engines have been processed by World Update.
         /// </summary>
-        protected void DestroyWith<TComponent>() where TComponent : struct
+        protected void DestroyWith<TComponent>() where TComponent : struct, IComponent
         {
             Destroy(ReadEntity<TComponent>());
         }
@@ -603,7 +601,7 @@ namespace Encompass
         /// Destroys all Entities containing a Component of the specified Type.
         /// Entity destruction takes place after all the Engines have been processed by World Update.
         /// </summary>
-        protected void DestroyAllWith<TComponent>() where TComponent : struct
+        protected void DestroyAllWith<TComponent>() where TComponent : struct, IComponent
         {
             foreach (var entity in ReadEntities<TComponent>())
             {
@@ -616,30 +614,30 @@ namespace Encompass
         /// Note that the Engine must Read the Component type that is being removed.
         /// If a Component with the specified type does not exist on the Entity, returns false and does not mutate the Entity.
         /// </summary>
-        protected void RemoveComponent<TComponent>(in Entity entity) where TComponent : struct
+        protected void RemoveComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
         {
-            var priority = WritePriorities.ContainsKey(typeof(TComponent)) ? WritePriorities[typeof(TComponent)] : DefaultWritePriority;
+            var priority = writePriorities.ContainsKey(typeof(TComponent)) ? writePriorities[typeof(TComponent)] : defaultWritePriority;
 
-            if (!WriteTypes.Contains(typeof(TComponent)))
+            if (!writeTypes.Contains(typeof(TComponent)))
             {
                 throw new IllegalWriteException("Engine {0} tried to remove undeclared Component {1}. Declare with Writes attribute.", GetType().Name, typeof(TComponent).Name);
             }
 
-            if (WriteImmediateTypes.Contains(typeof(TComponent)))
+            if (writeImmediateTypes.Contains(typeof(TComponent)))
             {
-                if (_componentManager.RemoveImmediate<TComponent>(entity.ID, priority))
+                if (componentManager.RemoveImmediate<TComponent>(entity.ID, priority))
                 {
-                    _trackingManager.ImmediateUpdateTracking(entity.ID, typeof(TComponent));
+                    trackingManager.ImmediateUpdateTracking(entity.ID, typeof(TComponent));
                 }
             }
             else
             {
-                _componentManager.Remove<TComponent>(entity.ID, priority);
+                componentManager.Remove<TComponent>(entity.ID, priority);
             }
 
-            if (_componentManager.HasExistingComponent<TComponent>(entity.ID))
+            if (componentManager.HasExistingComponent<TComponent>(entity.ID))
             {
-                _trackingManager.RegisterRemoval(entity.ID, typeof(TComponent));
+                trackingManager.RegisterRemoval(entity.ID, typeof(TComponent));
             }
         }
 
@@ -654,7 +652,7 @@ namespace Encompass
         /// <param name="easeOutTime">The time that will elapse before time is fully undilated.</param>
         protected void ActivateTimeDilation(double factor, double easeInTime, double activeTime, double easeOutTime)
         {
-            _timeManager.ActivateTimeDilation(factor, easeInTime, activeTime, easeOutTime);
+            timeManager.ActivateTimeDilation(factor, easeInTime, activeTime, easeOutTime);
         }
 
         /// <summary>
@@ -669,7 +667,7 @@ namespace Encompass
         /// <param name="easeOutTime">The time that will elapse before time is fully undilated.</param>
         protected void ActivateTimeDilation(double factor, double easeInTime, System.Func<double, double, double, double, double> easeInFunction, double activeTime, double easeOutTime)
         {
-            _timeManager.ActivateTimeDilation(factor, easeInTime, easeInFunction, activeTime, easeOutTime);
+            timeManager.ActivateTimeDilation(factor, easeInTime, easeInFunction, activeTime, easeOutTime);
         }
 
         /// <summary>
@@ -684,7 +682,7 @@ namespace Encompass
         /// <param name="easeOutFunction">An easing function for the easing out of time dilation.</param>
         protected void ActivateTimeDilation(double factor, double easeInTime, double activeTime, double easeOutTime, System.Func<double, double, double, double, double> easeOutFunction)
         {
-            _timeManager.ActivateTimeDilation(factor, easeInTime, activeTime, easeOutTime, easeOutFunction);
+            timeManager.ActivateTimeDilation(factor, easeInTime, activeTime, easeOutTime, easeOutFunction);
         }
 
         /// <summary>
@@ -700,7 +698,7 @@ namespace Encompass
         /// <param name="easeOutFunction">An easing function for the easing out of time dilation.</param>
         protected void ActivateTimeDilation(double factor, double easeInTime, System.Func<double, double, double, double, double> easeInFunction, double activeTime, double easeOutTime, System.Func<double, double, double, double, double> easeOutFunction)
         {
-            _timeManager.ActivateTimeDilation(factor, easeInTime, easeInFunction, activeTime, easeOutTime, easeOutFunction);
+            timeManager.ActivateTimeDilation(factor, easeInTime, easeInFunction, activeTime, easeOutTime, easeOutFunction);
         }
 
         /// <summary>
@@ -709,38 +707,38 @@ namespace Encompass
         /// <typeparam name="TMessage">The Message subtype.</typeparam>
         /// <param name="entity">The entity that all messages in the IEnumerable refer to.</param>
         /// <returns></returns>
-        protected IEnumerable<TMessage> ReadMessagesWithEntity<TMessage>(in Entity entity) where TMessage : struct, IHasEntity
+        protected IEnumerable<TMessage> ReadMessagesWithEntity<TMessage>(Entity entity) where TMessage : struct, IMessage, IHasEntity
         {
             CheckMessageRead<TMessage>();
-            return _messageManager.WithEntity<TMessage>(entity.ID);
+            return messageManager.WithEntity<TMessage>(entity.ID);
         }
 
         /// <summary>
         /// Efficiently reads a single Message of a given type that references a given Entity.
         /// It is recommended to use this method in conjunction with SomeMessageWithEntity to prevent errors.
         /// </summary>
-        protected ref readonly TMessage ReadMessageWithEntity<TMessage>(in Entity entity) where TMessage : struct, IHasEntity
+        protected TMessage ReadMessageWithEntity<TMessage>(Entity entity) where TMessage : struct, IMessage, IHasEntity
         {
             CheckMessageRead<TMessage>();
-            return ref _messageManager.WithEntitySingular<TMessage>(entity.ID);
+            return messageManager.WithEntitySingular<TMessage>(entity.ID);
         }
 
         /// <summary>
         /// Efficiently checks if any Message of a given type referencing a given Entity exists.
         /// </summary>
-        protected bool SomeMessageWithEntity<TMessage>(in Entity entity) where TMessage : struct, IHasEntity
+        protected bool SomeMessageWithEntity<TMessage>(Entity entity) where TMessage : struct, IMessage, IHasEntity
         {
             CheckMessageRead<TMessage>();
-            return _messageManager.SomeWithEntity<TMessage>(entity.ID);
+            return messageManager.SomeWithEntity<TMessage>(entity.ID);
         }
 
         internal void CheckAndUpdateTracking(int entityID)
         {
-            if (_trackedEntities.Contains(entityID) && !_entityQuery.CheckEntity(entityID, _componentManager.ExistingBits))
+            if (_trackedEntities.Contains(entityID) && !entityQuery.CheckEntity(entityID, componentManager.ExistingBits))
             {
                 _trackedEntities.Remove(entityID);
             }
-            else if (!_trackedEntities.Contains(entityID) && _entityQuery.CheckEntity(entityID, _componentManager.ExistingBits))
+            else if (!_trackedEntities.Contains(entityID) && entityQuery.CheckEntity(entityID, componentManager.ExistingBits))
             {
                 _trackedEntities.Add(entityID);
             }
@@ -748,11 +746,11 @@ namespace Encompass
 
         internal void ImmediateCheckAndUpdateTracking(int entityID)
         {
-            if (_trackedEntities.Contains(entityID) && !_entityQuery.ImmediateCheckEntity(entityID, _componentManager.ImmediateBits, _componentManager.ExistingBits))
+            if (_trackedEntities.Contains(entityID) && !entityQuery.ImmediateCheckEntity(entityID, componentManager.ImmediateBits, componentManager.ExistingBits))
             {
                 _trackedEntities.Remove(entityID);
             }
-            else if (!_trackedEntities.Contains(entityID) && _entityQuery.ImmediateCheckEntity(entityID, _componentManager.ImmediateBits, _componentManager.ExistingBits))
+            else if (!_trackedEntities.Contains(entityID) && entityQuery.ImmediateCheckEntity(entityID, componentManager.ImmediateBits, componentManager.ExistingBits))
             {
                 _trackedEntities.Add(entityID);
             }
@@ -764,34 +762,30 @@ namespace Encompass
         internal void BuildEntityQuery()
         {
             var withMask = BitSet512.Zero;
-            foreach (var type in QueryWithTypes)
+            foreach (var type in queryWithTypes)
             {
-                if (!_componentManager.TypeToIndex.ContainsKey(type)) { _componentManager.TypeToIndex.Add(type, _componentManager.TypeToIndex.Count); }
+                withMask = withMask.Set(componentManager.TypeToIndex[type]);
-                withMask = withMask.Set(_componentManager.TypeToIndex[type]);
             }
 
             var withoutMask = BitSet512.Zero;
-            foreach (var type in QueryWithoutTypes)
+            foreach (var type in queryWithoutTypes)
             {
-                if (!_componentManager.TypeToIndex.ContainsKey(type)) { _componentManager.TypeToIndex.Add(type, _componentManager.TypeToIndex.Count); }
+                withoutMask = withoutMask.Set(componentManager.TypeToIndex[type]);
-                withoutMask = withoutMask.Set(_componentManager.TypeToIndex[type]);
             }
 
             var immediateMask = BitSet512.Zero;
-            foreach (var type in ReadImmediateTypes)
+            foreach (var type in readImmediateTypes)
             {
-                if (!_componentManager.TypeToIndex.ContainsKey(type)) { _componentManager.TypeToIndex.Add(type, _componentManager.TypeToIndex.Count); }
+                immediateMask = immediateMask.Set(componentManager.TypeToIndex[type]);
-                immediateMask = immediateMask.Set(_componentManager.TypeToIndex[type]);
             }
 
             var existingMask = BitSet512.Zero;
-            foreach (var type in ReadTypes)
+            foreach (var type in readTypes)
             {
-                if (!_componentManager.TypeToIndex.ContainsKey(type)) { _componentManager.TypeToIndex.Add(type, _componentManager.TypeToIndex.Count); }
+                existingMask = existingMask.Set(componentManager.TypeToIndex[type]);
-                existingMask = existingMask.Set(_componentManager.TypeToIndex[type]);
             }
 
-            _entityQuery = new EntitySetQuery(
+            entityQuery = new EntitySetQuery(
                 withMask & immediateMask,
                 withMask & existingMask,
                 withoutMask & immediateMask,

encompass-cs/Engines/Spawner.cs

@@ -6,27 +6,27 @@ namespace Encompass
     /// A Spawner is a special type of Engine that runs a Spawn method in response to each Message it receives.
     /// Spawners are useful for organizing the building of new Entities in your game.
     /// </summary>
-    public abstract class Spawner<TMessage> : Engine where TMessage : struct
+    public abstract class Spawner<TMessage> : Engine where TMessage : struct, IMessage
     {
         protected Spawner() : base()
         {
             var readsAttribute = GetType().GetCustomAttribute<Reads>(false);
             if (readsAttribute != null)
             {
-                readsAttribute.ReadTypes.Add(typeof(TMessage));
+                readsAttribute.readTypes.Add(typeof(TMessage));
             }
 
-            ReceiveTypes.Add(typeof(TMessage));
+            receiveTypes.Add(typeof(TMessage));
         }
 
         public override void Update(double dt)
         {
-            foreach (ref readonly var message in ReadMessages<TMessage>())
+            foreach (var message in ReadMessages<TMessage>())
             {
                 Spawn(message);
             }
         }
 
-        protected abstract void Spawn(in TMessage message);
+        protected abstract void Spawn(TMessage message);
     }
 }

encompass-cs/Entity.cs

@@ -37,7 +37,7 @@ namespace Encompass
 
         public override int GetHashCode()
         {
-            return HashCode.Combine(ID);
+            return ID.GetHashCode();
         }
     }
 }

encompass-cs/EntityManager.cs

@@ -5,48 +5,48 @@ namespace Encompass
 {
     internal class EntityManager
     {
-        private readonly int _entityCapacity;
+        private readonly int entityCapacity;
-        private readonly IDManager _idManager = new IDManager();
+        private readonly IDManager idManager = new IDManager();
-        private readonly HashSet<int> _ids = new HashSet<int>();
+        private readonly HashSet<int> IDs = new HashSet<int>();
 
-        private readonly HashSet<int> _entitiesMarkedForDestroy = new HashSet<int>();
+        private readonly HashSet<int> entitiesMarkedForDestroy = new HashSet<int>();
 
-        private readonly ComponentManager _componentManager;
+        private readonly ComponentManager componentManager;
 
         public IEnumerable<int> EntityIDs
         {
-            get { return _ids; }
+            get { return IDs; }
         }
 
         public EntityManager(ComponentManager componentManager, int entityCapacity)
         {
-            _componentManager = componentManager;
+            this.componentManager = componentManager;
-            _entityCapacity = entityCapacity;
+            this.entityCapacity = entityCapacity;
         }
 
         private int NextID()
         {
-            return _idManager.NextID();
+            return idManager.NextID();
         }
 
         public Entity CreateEntity()
         {
-            if (_ids.Count < _entityCapacity)
+            if (IDs.Count < entityCapacity)
             {
                 var id = NextID();
                 var entity = new Entity(id);
-                _ids.Add(id);
+                IDs.Add(id);
                 return entity;
             }
             else
             {
-                throw new EntityOverflowException("The number of entities has exceeded the entity capacity of {0}", _entityCapacity);
+                throw new EntityOverflowException("The number of entities has exceeded the entity capacity of {0}", entityCapacity);
             }
         }
 
         public bool EntityExists(int id)
         {
-            return _ids.Contains(id);
+            return IDs.Contains(id);
         }
 
         public Entity GetEntity(int id)
@@ -61,20 +61,20 @@ namespace Encompass
 
         public void MarkForDestroy(int entityID)
         {
-            _entitiesMarkedForDestroy.Add(entityID);
+            entitiesMarkedForDestroy.Add(entityID);
         }
 
         public void DestroyMarkedEntities(IEnumerable<Engine> engines)
         {
-            foreach (var entityID in _entitiesMarkedForDestroy)
+            foreach (var entityID in entitiesMarkedForDestroy)
             {
                 foreach (var engine in engines) { engine.RegisterDestroyedEntity(entityID); }
-                _componentManager.MarkAllComponentsOnEntityForRemoval(entityID);
+                componentManager.MarkAllComponentsOnEntityForRemoval(entityID);
-                _ids.Remove(entityID);
+                IDs.Remove(entityID);
-                _idManager.Free(entityID);
+                idManager.Free(entityID);
             }
 
-            _entitiesMarkedForDestroy.Clear();
+            entitiesMarkedForDestroy.Clear();
         }
 
         // NOTE: this is very suboptimal
@@ -82,7 +82,7 @@ namespace Encompass
         {
             foreach (var id in EntityIDs)
             {
-                if (_componentManager.UpToDateEntityIsEmpty(id))
+                if (componentManager.UpToDateEntityIsEmpty(id))
                 {
                     MarkForDestroy(id);
                 }

encompass-cs/EntitySetQuery.cs

@@ -1,4 +1,6 @@
-namespace Encompass
+using MoonTools.FastCollections;
+
+namespace Encompass
 {
     internal struct EntitySetQuery
     {

encompass-cs/Exceptions/IllegalReadTypeException.cs

@@ -2,9 +2,9 @@ using System;
 
 namespace Encompass.Exceptions
 {
-    public class NoMessageOfTypeException : Exception
+    public class IllegalReadTypeException : Exception
     {
-        public NoMessageOfTypeException(
+        public IllegalReadTypeException(
             string format,
             params object[] args
         ) : base(string.Format(format, args)) { }

encompass-cs/Exceptions/IllegalSendTypeException.cs

@@ -1,11 +1,10 @@
-
 using System;
 
 namespace Encompass.Exceptions
 {
-    public class IllegalDrawLayerException : Exception
+    public class IllegalSendTypeException : Exception
     {
-        public IllegalDrawLayerException(
+        public IllegalSendTypeException(
             string format,
             params object[] args
         ) : base(string.Format(format, args)) { }

encompass-cs/Exceptions/NoComponentOfTypeException.cs

@@ -1,12 +1,25 @@
 using System;
+using System.Runtime.Serialization;
 
 namespace Encompass.Exceptions
 {
-    public class NoComponentOfTypeException : Exception
+    [Serializable]
+    internal class NoComponentOfTypeException : Exception
     {
-        public NoComponentOfTypeException(
+        public NoComponentOfTypeException()
-            string format,
+        {
-            params object[] args
+        }
-        ) : base(string.Format(format, args)) { }
+
+        public NoComponentOfTypeException(string message) : base(message)
+        {
+        }
+
+        public NoComponentOfTypeException(string message, Exception innerException) : base(message, innerException)
+        {
+        }
+
+        protected NoComponentOfTypeException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
     }
 }

encompass-cs/Graph/DirectedGraph.cs

@@ -1,390 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-
-namespace Encompass
-{
-    internal class DirectedGraph<TNode> where TNode : IEquatable<TNode>
-    {
-        protected HashSet<TNode> nodes = new HashSet<TNode>();
-        protected Dictionary<TNode, HashSet<TNode>> neighbors = new Dictionary<TNode, HashSet<TNode>>();
-
-        protected HashSet<(TNode, TNode)> edges = new HashSet<(TNode, TNode)>();
-
-        public IEnumerable<TNode> Nodes => nodes;
-        public IEnumerable<(TNode, TNode)> Edges => edges;
-
-        public void AddNode(TNode node)
-        {
-            if (!Exists(node))
-            {
-                nodes.Add(node);
-                neighbors.Add(node, new HashSet<TNode>());
-            }
-        }
-
-        public void AddNodes(params TNode[] nodes)
-        {
-            foreach (var node in nodes)
-            {
-                AddNode(node);
-            }
-        }
-
-        public void RemoveNode(TNode node)
-        {
-            CheckNodes(node);
-
-            var edgesToRemove = new List<(TNode, TNode)>();
-
-            foreach (var entry in neighbors)
-            {
-                if (entry.Value.Contains(node))
-                {
-                    edgesToRemove.Add((entry.Key, node));
-                }
-            }
-
-            foreach (var edge in edgesToRemove)
-            {
-                RemoveEdge(edge.Item1, edge.Item2);
-            }
-
-            nodes.Remove(node);
-            neighbors.Remove(node);
-        }
-
-        public void RemoveEdge(TNode v, TNode u)
-        {
-            CheckEdge(v, u);
-            neighbors[v].Remove(u);
-            edges.Remove((v, u));
-        }
-
-        public void AddEdge(TNode v, TNode u)
-        {
-            CheckNodes(v, u);
-            if (Exists(v, u)) { throw new ArgumentException($"Edge between {v} and {u} already exists in the graph"); }
-
-            if (v.Equals(u)) { throw new ArgumentException("Self-edges are not allowed in a simple graph. Use a multigraph instead"); }
-
-            neighbors[v].Add(u);
-            edges.Add((v, u));
-        }
-
-        public bool Exists(TNode node)
-        {
-            return nodes.Contains(node);
-        }
-
-        public bool Exists(TNode v, TNode u)
-        {
-            CheckNodes(v, u);
-            return edges.Contains((v, u));
-        }
-
-        protected void CheckNodes(params TNode[] givenNodes)
-        {
-            foreach (var node in givenNodes)
-            {
-                if (!Exists(node))
-                {
-                    throw new System.ArgumentException($"Vertex {node} does not exist in the graph");
-                }
-            }
-        }
-
-        protected void CheckEdge(TNode v, TNode u)
-        {
-            CheckNodes(v, u);
-            if (!Exists(v, u)) { throw new ArgumentException($"Edge between vertex {v} and vertex {u} does not exist in the graph"); }
-        }
-
-        public IEnumerable<TNode> Neighbors(TNode node)
-        {
-            CheckNodes(node);
-            return neighbors[node];
-        }
-
-        public DirectedGraph<TNode> Clone()
-        {
-            var clone = new DirectedGraph<TNode>();
-            clone.AddNodes(Nodes.ToArray());
-
-            foreach (var v in Nodes)
-            {
-                foreach (var n in Neighbors(v))
-                {
-                    clone.AddEdge(v, n);
-                }
-            }
-
-            return clone;
-        }
-
-        public DirectedGraph<TNode> SubGraph(params TNode[] subVertices)
-        {
-            var subGraph = new DirectedGraph<TNode>();
-            subGraph.AddNodes(subVertices.ToArray());
-
-            foreach (var n in Nodes)
-            {
-                if (Nodes.Contains(n))
-                {
-                    var neighbors = Neighbors(n);
-                    foreach (var u in neighbors)
-                    {
-                        if (subVertices.Contains(u))
-                        {
-                            subGraph.AddEdge(n, u);
-                        }
-                    }
-                }
-            }
-
-            return subGraph;
-        }
-
-        private IEnumerable<TNode> PostorderNodeDFSHelper(HashSet<TNode> discovered, TNode v)
-        {
-            discovered.Add(v);
-
-            foreach (var neighbor in Neighbors(v))
-            {
-                if (!discovered.Contains(neighbor))
-                {
-                    foreach (var node in PostorderNodeDFSHelper(discovered, neighbor))
-                    {
-                        yield return node;
-                    }
-                }
-            }
-
-            yield return v;
-        }
-
-        protected IEnumerable<TNode> PostorderNodeDFS()
-        {
-            var dfsDiscovered = new HashSet<TNode>();
-
-            foreach (var node in Nodes)
-            {
-                if (!dfsDiscovered.Contains(node))
-                {
-                    foreach (var thing in PostorderNodeDFSHelper(dfsDiscovered, node))
-                    {
-                        yield return thing;
-                    }
-                }
-            }
-        }
-
-        public IEnumerable<TNode> TopologicalSort()
-        {
-            return PostorderNodeDFS().Reverse();
-        }
-
-        public bool Cyclic()
-        {
-            return StronglyConnectedComponents().Any((scc) => scc.Count() > 1);
-        }
-
-        public IEnumerable<IEnumerable<TNode>> SimpleCycles()
-        {
-            void unblock(TNode thisnode, HashSet<TNode> blocked, Dictionary<TNode, HashSet<TNode>> B) //refactor to remove closure
-            {
-                var stack = new Stack<TNode>();
-                stack.Push(thisnode);
-
-                while (stack.Count > 0)
-                {
-                    var node = stack.Pop();
-                    if (blocked.Contains(thisnode))
-                    {
-                        blocked.Remove(thisnode);
-                        if (B.ContainsKey(node))
-                        {
-                            foreach (var n in B[node])
-                            {
-                                if (!stack.Contains(n))
-                                {
-                                    stack.Push(n);
-                                }
-                            }
-                            B[node].Clear();
-                        }
-                    }
-                }
-            }
-
-            List<List<TNode>> result = new List<List<TNode>>();
-            var subGraph = Clone();
-
-            var sccs = new Stack<IEnumerable<TNode>>();
-            foreach (var scc in StronglyConnectedComponents())
-            {
-                sccs.Push(scc);
-            }
-
-            while (sccs.Count > 0)
-            {
-                var scc = new Stack<TNode>(sccs.Pop());
-                var startNode = scc.Pop();
-                var path = new Stack<TNode>();
-                path.Push(startNode);
-                var blocked = new HashSet<TNode>
-                {
-                    startNode
-                };
-                var closed = new HashSet<TNode>();
-                var B = new Dictionary<TNode, HashSet<TNode>>();
-                var stack = new Stack<(TNode, Stack<TNode>)>();
-                stack.Push((startNode, new Stack<TNode>(subGraph.Neighbors(startNode))));
-
-                while (stack.Count > 0)
-                {
-                    var entry = stack.Peek();
-                    var thisnode = entry.Item1;
-                    var neighbors = entry.Item2;
-
-                    if (neighbors.Count > 0)
-                    {
-                        var nextNode = neighbors.Pop();
-
-                        if (nextNode.Equals(startNode))
-                        {
-                            var resultPath = new List<TNode>();
-                            foreach (var v in path)
-                            {
-                                resultPath.Add(v);
-                            }
-                            result.Add(resultPath);
-                            foreach (var v in path)
-                            {
-                                closed.Add(v);
-                            }
-                        }
-                        else if (!blocked.Contains(nextNode))
-                        {
-                            path.Push(nextNode);
-                            stack.Push((nextNode, new Stack<TNode>(subGraph.Neighbors(nextNode))));
-                            closed.Remove(nextNode);
-                            blocked.Add(nextNode);
-                            continue;
-                        }
-                    }
-
-                    if (neighbors.Count == 0)
-                    {
-                        if (closed.Contains(thisnode))
-                        {
-                            unblock(thisnode, blocked, B);
-                        }
-                        else
-                        {
-                            foreach (var neighbor in subGraph.Neighbors(thisnode))
-                            {
-                                if (!B.ContainsKey(neighbor))
-                                {
-                                    B[neighbor] = new HashSet<TNode>();
-                                }
-                                B[neighbor].Add(thisnode);
-                            }
-                        }
-
-                        stack.Pop();
-                        path.Pop();
-                    }
-                }
-
-                subGraph.RemoveNode(startNode);
-                var H = subGraph.SubGraph(scc.ToArray());
-                var HSccs = H.StronglyConnectedComponents();
-                foreach (var HScc in HSccs)
-                {
-                    sccs.Push(HScc);
-                }
-            }
-
-            return result.Distinct(new SimpleCycleComparer<TNode>());
-        }
-
-        protected IEnumerable<IEnumerable<TNode>> StronglyConnectedComponents()
-        {
-            var preorder = new Dictionary<TNode, uint>();
-            var lowlink = new Dictionary<TNode, uint>();
-            var sccFound = new Dictionary<TNode, bool>();
-            var sccQueue = new Stack<TNode>();
-
-            uint preorderCounter = 0;
-
-            foreach (var source in Nodes)
-            {
-                if (!sccFound.ContainsKey(source))
-                {
-                    var queue = new Stack<TNode>();
-                    queue.Push(source);
-
-                    while (queue.Count > 0)
-                    {
-                        var v = queue.Peek();
-                        if (!preorder.ContainsKey(v))
-                        {
-                            preorderCounter++;
-                            preorder[v] = preorderCounter;
-                        }
-
-                        var done = true;
-                        var vNeighbors = Neighbors(v);
-                        foreach (var w in vNeighbors)
-                        {
-                            if (!preorder.ContainsKey(w))
-                            {
-                                queue.Push(w);
-                                done = false;
-                                break;
-                            }
-                        }
-
-                        if (done)
-                        {
-                            lowlink[v] = preorder[v];
-                            foreach (var w in vNeighbors)
-                            {
-                                if (!sccFound.ContainsKey(w))
-                                {
-                                    if (preorder[w] > preorder[v])
-                                    {
-                                        lowlink[v] = Math.Min(lowlink[v], lowlink[w]);
-                                    }
-                                    else
-                                    {
-                                        lowlink[v] = Math.Min(lowlink[v], preorder[w]);
-                                    }
-                                }
-                            }
-                            queue.Pop();
-                            if (lowlink[v] == preorder[v])
-                            {
-                                sccFound[v] = true;
-                                var scc = new List<TNode>() { v };
-                                while (sccQueue.Count > 0 && preorder[sccQueue.Peek()] > preorder[v])
-                                {
-                                    var k = sccQueue.Pop();
-                                    sccFound[k] = true;
-                                    scc.Add(k);
-                                }
-
-                                yield return scc;
-                            }
-                            else
-                            {
-                                sccQueue.Push(v);
-                            }
-                        }
-                    }
-                }
-            }
-        }
-    }
-}

encompass-cs/Graph/SimpleCycleComparer.cs

@@ -1,18 +0,0 @@
-using System.Collections.Generic;
-using System.Linq;
-
-namespace Encompass
-{
-    internal class SimpleCycleComparer<TNode> : IEqualityComparer<IEnumerable<TNode>>
-    {
-        public bool Equals(IEnumerable<TNode> x, IEnumerable<TNode> y)
-        {
-            return x.SequenceEqual(y);
-        }
-
-        public int GetHashCode(IEnumerable<TNode> obj)
-        {
-            return obj.Aggregate(0, (current, next) => current.GetHashCode() ^ next.GetHashCode());
-        }
-    }
-}

encompass-cs/IComponent.cs

@@ -0,0 +1,7 @@
+namespace Encompass
+{
+    /// <summary>
+    /// Structs that implement IComponent are considered to be Components.
+    /// </summary>
+    public interface IComponent { }
+}

encompass-cs/IDManager.cs

@@ -4,25 +4,25 @@ namespace Encompass
 {
     internal class IDManager
     {
-        int _nextID = 0;
+        int nextID = 0;
 
-        private readonly Stack<int> _availableIDs = new Stack<int>();
+        private Stack<int> availableIDs = new Stack<int>();
 
         public int NextID()
         {
-            if (_availableIDs.Count > 0)
+            if (availableIDs.Count > 0)
             {
-                return _availableIDs.Pop();
+                return availableIDs.Pop();
             }
             else
             {
-                return _nextID++;
+                return nextID++;
             }
         }
 
-        public void Free(int id)
+        public void Free(int ID)
         {
-            _availableIDs.Push(id);
+            availableIDs.Push(ID);
         }
     }
 }

encompass-cs/IMessage.cs

@@ -0,0 +1,7 @@
+namespace Encompass
+{
+    /// <summary>
+    /// Structs that implement IMessage are considered to be Messages.
+    /// </summary>
+    public interface IMessage { }
+}

encompass-cs/Interfaces/IDrawableComponent.cs

@@ -0,0 +1,7 @@
+namespace Encompass
+{
+    public interface IDrawableComponent
+    {
+        int Layer { get; set; }
+    }
+}

encompass-cs/MessageManager.cs

@@ -1,71 +1,72 @@
-using System;
 using System.Collections.Generic;
 
 namespace Encompass
 {
     internal class MessageManager
     {
-        private readonly TimeManager _timeManager;
+        private readonly TimeManager timeManager;
-        private readonly MessageStore _messageStore = new MessageStore();
+        private readonly MessageStore messageStore = new MessageStore();
 
         public MessageManager(TimeManager timeManager)
         {
-            _timeManager = timeManager;
+            this.timeManager = timeManager;
         }
 
-        internal void AddMessage<TMessage>(in TMessage message) where TMessage : struct
+        internal void AddMessage<TMessage>(TMessage message) where TMessage : struct, IMessage
         {
-            _messageStore.AddMessage(message);
+            messageStore.AddMessage(message);
         }
 
-        internal void AddMessage<TMessage>(in TMessage message, double time) where TMessage : struct
+        internal void AddMessage<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
-            _messageStore.AddMessage(message, time);
+            messageStore.AddMessage(message, time);
         }
 
-        internal void AddMessageIgnoringTimeDilation<TMessage>(in TMessage message, double time) where TMessage : struct
+        internal void AddMessageIgnoringTimeDilation<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
-            _messageStore.AddMessageIgnoringTimeDilation(message, time);
+            messageStore.AddMessageIgnoringTimeDilation(message, time);
         }
 
         internal void ClearMessages()
         {
-            _messageStore.ClearAll();
+            messageStore.ClearAll();
         }
 
         internal void ProcessDelayedMessages(double dt)
         {
-            _messageStore.ProcessDelayedMessages(dt * _timeManager.TimeDilationFactor, dt);
+            messageStore.ProcessDelayedMessages(dt * timeManager.TimeDilationFactor, dt);
         }
 
-        internal ReadOnlySpan<TMessage> GetMessagesByType<TMessage>() where TMessage : struct
+        internal IEnumerable<TMessage> GetMessagesByType<TMessage>() where TMessage : struct, IMessage
         {
-            return _messageStore.All<TMessage>();
+            return messageStore.All<TMessage>();
         }
 
-        internal bool Any<TMessage>() where TMessage : struct
+        internal bool Any<TMessage>() where TMessage : struct, IMessage
         {
-            return _messageStore.Any<TMessage>();
+            return messageStore.Any<TMessage>();
         }
 
-        internal ref readonly TMessage First<TMessage>() where TMessage : struct
+        internal TMessage First<TMessage>() where TMessage : struct, IMessage
         {
-            return ref _messageStore.First<TMessage>();
+            return messageStore.First<TMessage>();
         }
 
-        internal IEnumerable<TMessage> WithEntity<TMessage>(int entityID) where TMessage : struct, IHasEntity
+        internal IEnumerable<TMessage> WithEntity<TMessage>(int entityID) where TMessage : struct, IMessage, IHasEntity
         {
-            return _messageStore.WithEntity<TMessage>(entityID);
+            return messageStore.WithEntity<TMessage>(entityID);
         }
 
-        internal ref readonly TMessage WithEntitySingular<TMessage>(int entityID) where TMessage : struct, IHasEntity
+        internal TMessage WithEntitySingular<TMessage>(int entityID) where TMessage : struct, IMessage, IHasEntity
         {
-            return ref _messageStore.FirstWithEntity<TMessage>(entityID);
+            var enumerator = messageStore.WithEntity<TMessage>(entityID).GetEnumerator();
+            enumerator.MoveNext();
+            return enumerator.Current;
         }
 
-        internal bool SomeWithEntity<TMessage>(int entityID) where TMessage : struct, IHasEntity
+        internal bool SomeWithEntity<TMessage>(int entityID) where TMessage : struct, IMessage, IHasEntity
         {
-            return _messageStore.SomeWithEntity<TMessage>(entityID);
+            return messageStore.SomeWithEntity<TMessage>(entityID);
         }
     }
 }

encompass-cs/RenderManager.cs

@@ -1,27 +1,51 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 
 namespace Encompass
 {
     internal class RenderManager
     {
-        private readonly EntityManager _entityManager;
+        private readonly EntityManager entityManager;
-        private readonly List<Renderer> renderers = new List<Renderer>();
+        private readonly DrawLayerManager drawLayerManager;
 
-        public RenderManager(EntityManager entityManager)
+        private readonly Dictionary<Type, Action<Entity, IComponent>> drawComponentTypeToOrderedRenderer = new Dictionary<Type, Action<Entity, IComponent>>(256);
+
+        public RenderManager(EntityManager entityManager, DrawLayerManager drawLayerManager)
         {
-            _entityManager = entityManager;
+            this.entityManager = entityManager;
+            this.drawLayerManager = drawLayerManager;
         }
 
-        public void AddRenderer(Renderer renderer)
+        public void RegisterOrderedRenderer<TComponent>(Action<Entity, IComponent> renderAction) where TComponent : struct, IComponent
         {
-            renderers.Add(renderer);
+            drawComponentTypeToOrderedRenderer.Add(typeof(TComponent), renderAction);
+            drawLayerManager.RegisterOrderedDrawable<TComponent>();
         }
 
-        public void Draw(double dt, double alpha)
+        public void RegisterGeneralRendererWithLayer(GeneralRenderer renderer, int layer)
         {
-            foreach (var renderer in renderers)
+            drawLayerManager.RegisterGeneralRendererWithLayer(renderer, layer);
+        }
+
+        public void Draw()
+        {
+            foreach (var layer in drawLayerManager.LayerOrder)
             {
-                renderer.Render(dt, alpha);
+                var generalRendererSet = drawLayerManager.GeneralRenderersByLayer(layer);
+
+                foreach (var (entityID, componentType, component) in drawLayerManager.AllInLayer(layer))
+                {
+                    if (drawComponentTypeToOrderedRenderer.ContainsKey(componentType))
+                    {
+                        var internalRenderAction = drawComponentTypeToOrderedRenderer[componentType];
+                        internalRenderAction(entityManager.GetEntity(entityID), component);
+                    }
+                }
+
+                foreach (var generalRenderer in generalRendererSet)
+                {
+                    generalRenderer.Render();
+                }
             }
         }
     }

encompass-cs/Renderer.cs

@@ -1,68 +1,75 @@
-using System;
+using System.Collections.Generic;
-using System.Collections.Generic;
 
 namespace Encompass
 {
     public abstract class Renderer
     {
-        internal EntityManager _entityManager;
+        internal EntityManager entityManager;
-        internal ComponentManager _componentManager;
+        internal ComponentManager componentManager;
 
         internal void AssignEntityManager(EntityManager entityManager)
         {
-            _entityManager = entityManager;
+            this.entityManager = entityManager;
         }
 
         internal void AssignComponentManager(ComponentManager componentManager)
         {
-            _componentManager = componentManager;
+            this.componentManager = componentManager;
         }
 
-        public abstract void Render(double dt, double alpha);
+        protected IEnumerable<Entity> ReadEntities<TComponent>() where TComponent : struct, IComponent
-
-        protected ReadOnlySpan<Entity> ReadEntities<TComponent>() where TComponent : struct
         {
-            return _componentManager.GetExistingEntities<TComponent>();
+            foreach (var pair in ReadComponentsIncludingEntity<TComponent>())
+            {
+                yield return pair.Item2;
+            }
         }
 
-        protected IEnumerable<Entity> ReadEntitiesAsEnumerable<TComponent>() where TComponent : struct
+        protected Entity ReadEntity<TComponent>() where TComponent : struct, IComponent
         {
-            return _componentManager.GetExistingEntitiesAsEnumerable<TComponent>();
+            return ReadComponentIncludingEntity<TComponent>().Item2;
         }
 
-        protected ref readonly Entity ReadEntity<TComponent>() where TComponent : struct
+        protected IEnumerable<TComponent> ReadComponents<TComponent>() where TComponent : struct, IComponent
         {
-            return ref _componentManager.ExistingSingularEntity<TComponent>();
+            return componentManager.GetComponentsByType<TComponent>();
         }
 
-        protected ReadOnlySpan<TComponent> ReadComponents<TComponent>() where TComponent : struct
+        protected IEnumerable<(TComponent, Entity)> ReadComponentsIncludingEntity<TComponent>() where TComponent : struct, IComponent
         {
-            return _componentManager.GetComponentsByType<TComponent>();
+            foreach (var (component, id) in componentManager.GetComponentsIncludingEntity<TComponent>())
+            {
+                yield return (component, entityManager.GetEntity(id));
+            }
         }
 
-        protected IEnumerable<TComponent> ReadComponentsAsEnumerable<TComponent>() where TComponent : struct
+        protected TComponent ReadComponent<TComponent>() where TComponent : struct, IComponent
         {
-            return _componentManager.GetComponentsByTypeEnumerable<TComponent>();
+            var enumerator = ReadComponents<TComponent>().GetEnumerator();
+            enumerator.MoveNext();
+            return enumerator.Current;
         }
 
-        protected ref readonly TComponent ReadComponent<TComponent>() where TComponent : struct
+        protected (TComponent, Entity) ReadComponentIncludingEntity<TComponent>() where TComponent : struct, IComponent
         {
-            return ref _componentManager.ExistingSingular<TComponent>();
+            var enumerator = ReadComponentsIncludingEntity<TComponent>().GetEnumerator();
+            enumerator.MoveNext();
+            return enumerator.Current;
         }
 
-        protected ref readonly TComponent GetComponent<TComponent>(Entity entity) where TComponent : struct
+        protected TComponent GetComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
         {
-            return ref _componentManager.GetComponentByEntityAndType<TComponent>(entity.ID);
+            return componentManager.GetComponentByEntityAndType<TComponent>(entity.ID);
         }
 
-        protected bool HasComponent<TComponent>(Entity entity) where TComponent : struct
+        protected bool HasComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
         {
-            return _componentManager.EntityHasComponentOfType<TComponent>(entity.ID);
+            return componentManager.EntityHasComponentOfType<TComponent>(entity.ID);
         }
 
-        protected bool SomeComponent<TComponent>() where TComponent : struct
+        protected bool SomeComponent<TComponent>() where TComponent : struct, IComponent
         {
-            return _componentManager.SomeExistingComponent<TComponent>();
+            return componentManager.SomeExistingComponent<TComponent>();
         }
     }
 }

encompass-cs/Renderers/GeneralRenderer.cs

@@ -0,0 +1,11 @@
+namespace Encompass
+{
+    /// <summary>
+    /// GeneralRenderer is a Renderer which generically reads the game state in order to draw elements to the screen.
+    /// GeneralRenderers have a layer specified when they are added to the World.
+    /// </summary>
+    public abstract class GeneralRenderer : Renderer
+    {
+        public abstract void Render();
+    }
+}

encompass-cs/Renderers/OrderedRenderer.cs

@@ -0,0 +1,17 @@
+using System;
+
+namespace Encompass
+{
+    /// <summary>
+    /// OrdereredRenderer provides a structure for the common pattern of wishing to draw a specific DrawComponent at a specific layer.
+    /// </summary>
+    public abstract class OrderedRenderer<TComponent> : Renderer where TComponent : struct, IComponent, IDrawableComponent
+    {
+        public abstract void Render(Entity entity, TComponent drawComponent);
+
+        internal void InternalRender(Entity entity, IComponent component)
+        {
+            Render(entity, (TComponent)component);
+        }
+    }
+}

encompass-cs/TimeDilationData.cs

@@ -1,56 +1,35 @@
-using System;
-
 namespace Encompass
 {
     internal struct TimeDilationData
     {
-        private readonly double _factor;
+        public double elapsedTime;
+        public double easeInTime;
+        public System.Func<double, double, double, double, double> easeInFunction;
+        public double activeTime;
+        public double easeOutTime;
+        public System.Func<double, double, double, double, double> easeOutFunction;
+        public double factor;
 
         public double Factor
         {
             get
             {
-                if (ElapsedTime < EaseInTime)
+                if (elapsedTime < easeInTime)
                 {
-                    return EaseInFunction(ElapsedTime, 1, _factor - 1, EaseInTime);
+                    return easeInFunction(elapsedTime, 1, factor - 1, easeInTime);
                 }
-                else if (ElapsedTime < EaseInTime + ActiveTime)
+                else if (elapsedTime < easeInTime + activeTime)
                 {
-                    return _factor;
+                    return factor;
                 }
-                else if (ElapsedTime < EaseInTime + ActiveTime + EaseOutTime)
+                else if (elapsedTime < easeInTime + activeTime + easeOutTime)
                 {
-                    var elapsedOutTime = ElapsedTime - EaseInTime - ActiveTime;
+                    var elapsedOutTime = elapsedTime - easeInTime - activeTime;
-                    return EaseOutFunction(elapsedOutTime, _factor, 1 - _factor, EaseOutTime);
+                    return easeOutFunction(elapsedOutTime, factor, 1 - factor, easeOutTime);
                 }
 
                 return 1;
             }
         }
-
-        public double ElapsedTime { get; set; }
-        public double EaseInTime { get; }
-        public Func<double, double, double, double, double> EaseInFunction { get; }
-        public double ActiveTime { get; }
-        public double EaseOutTime { get; }
-        public Func<double, double, double, double, double> EaseOutFunction { get; }
-
-        public TimeDilationData(
-            double factor,
-            double easeInTime,
-            Func<double, double, double, double, double> easeInfunction,
-            double activeTime,
-            double easeOutTime,
-            Func<double, double, double, double, double> easeOutFunction
-        )
-        {
-            _factor = factor;
-            EaseInTime = easeInTime;
-            EaseInFunction = easeInfunction;
-            ActiveTime = activeTime;
-            EaseOutTime = easeOutTime;
-            EaseOutFunction = easeOutFunction;
-            ElapsedTime = 0;
-        }
     }
 }

encompass-cs/TimeManager.cs

@@ -4,7 +4,7 @@ namespace Encompass
 {
     internal class TimeManager
     {
-        private readonly List<TimeDilationData> _timeDilationDatas = new List<TimeDilationData>(32);
+        private readonly List<TimeDilationData> timeDilationDatas = new List<TimeDilationData>(32);
 
         private double Linear(double t, double b, double c, double d)
         {
@@ -15,36 +15,36 @@ namespace Encompass
         {
             get
             {
-                if (_timeDilationDatas.Count == 0) { return 1; }
+                if (timeDilationDatas.Count == 0) { return 1; }
                 var average = 0.0;
-                foreach (var data in _timeDilationDatas)
+                foreach (var data in timeDilationDatas)
                 {
                     average += data.Factor;
                 }
-                return average / _timeDilationDatas.Count;
+                return average / timeDilationDatas.Count;
             }
         }
 
         public bool TimeDilationActive
         {
-            get => _timeDilationDatas.Count != 0;
+            get => timeDilationDatas.Count != 0;
         }
 
         public void Update(double dt)
         {
-            for (var i = _timeDilationDatas.Count - 1; i >= 0; i--)
+            for (var i = timeDilationDatas.Count - 1; i >= 0; i--)
             {
-                var data = _timeDilationDatas[i];
+                var data = timeDilationDatas[i];
 
-                data.ElapsedTime += dt;
+                data.elapsedTime += dt;
 
-                if (data.ElapsedTime > data.EaseInTime + data.ActiveTime + data.EaseOutTime)
+                if (data.elapsedTime > data.easeInTime + data.activeTime + data.easeOutTime)
                 {
-                    _timeDilationDatas.RemoveAt(i);
+                    timeDilationDatas.RemoveAt(i);
                 }
                 else
                 {
-                    _timeDilationDatas[i] = data;
+                    timeDilationDatas[i] = data;
                 }
             }
         }
@@ -66,15 +66,16 @@ namespace Encompass
 
         public void ActivateTimeDilation(double factor, double easeInTime, System.Func<double, double, double, double, double> easeInFunction, double activeTime, double easeOutTime, System.Func<double, double, double, double, double> easeOutFunction)
         {
-            _timeDilationDatas.Add(new TimeDilationData
+            timeDilationDatas.Add(new TimeDilationData
-            (
+            {
-                factor,
+                elapsedTime = 0,
-                easeInTime,
+                easeInTime = easeInTime,
-                easeInFunction,
+                easeInFunction = easeInFunction,
-                activeTime,
+                activeTime = activeTime,
-                easeOutTime,
+                easeOutTime = easeOutTime,
-                easeOutFunction
+                easeOutFunction = easeOutFunction,
-            ));
+                factor = factor
+            });
         }
     }
 }

encompass-cs/TrackingManager.cs

@@ -5,13 +5,13 @@ namespace Encompass
 {
     internal class TrackingManager
     {
-        private readonly Dictionary<Type, HashSet<Engine>> _immediateComponentTypesToEngines = new Dictionary<Type, HashSet<Engine>>();
+        private Dictionary<Type, HashSet<Engine>> _immediateComponentTypesToEngines = new Dictionary<Type, HashSet<Engine>>();
-        private readonly Dictionary<Type, HashSet<Engine>> _componentTypesToEngines = new Dictionary<Type, HashSet<Engine>>();
+        private Dictionary<Type, HashSet<Engine>> _componentTypesToEngines = new Dictionary<Type, HashSet<Engine>>();
 
-        private readonly HashSet<(int, Type)> _additions = new HashSet<(int, Type)>();
+        private HashSet<(int, Type)> _additions = new HashSet<(int, Type)>();
-        private readonly HashSet<(int, Type)> _removals = new HashSet<(int, Type)>();
+        private HashSet<(int, Type)> _removals = new HashSet<(int, Type)>();
 
-        private readonly HashSet<(int, Engine)> _pairsToCheck = new HashSet<(int, Engine)>();
+        private HashSet<(int, Engine)> _pairsToCheck = new HashSet<(int, Engine)>();
 
         public void RegisterComponentTypeToEngine(Type type, Engine engine)
         {

encompass-cs/UberEngine.cs

@@ -1,24 +1,24 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Reflection;
 
 namespace Encompass
 {
     internal class UberEngine : Engine
     {
-        private readonly IEnumerable<Type> _componentTypes;
+        private IEnumerable<Type> _componentTypes;
-        private readonly IEnumerable<Type> _messageTypes;
+        private IEnumerable<Type> _messageTypes;
         public Entity Entity { get; private set; }
 
         public UberEngine(IEnumerable<Type> componentTypes, IEnumerable<Type> messageTypes)
         {
             _componentTypes = componentTypes;
             _messageTypes = messageTypes;
-            AddTypes.UnionWith(componentTypes);
+            readTypes.UnionWith(componentTypes);
-            ReadTypes.UnionWith(componentTypes);
+            writeTypes.UnionWith(componentTypes);
-            WriteTypes.UnionWith(componentTypes);
+            sendTypes.UnionWith(messageTypes);
-            SendTypes.UnionWith(messageTypes);
+            receiveTypes.UnionWith(messageTypes);
-            ReceiveTypes.UnionWith(messageTypes);
         }
 
         public void Write()
@@ -27,8 +27,7 @@ namespace Encompass
 
             foreach (var type in _componentTypes)
             {
-                var instance = Activator.CreateInstance(type);
+                var instanceParam = new object[] { Entity, Activator.CreateInstance(type) };
-                var instanceParam = new object[] { Entity, instance };
                 var setComponentMethod = typeof(Engine).GetMethod("SetComponent", BindingFlags.NonPublic | BindingFlags.Instance);
                 var genericSetComponentMethod = setComponentMethod.MakeGenericMethod(type);
                 genericSetComponentMethod.Invoke(this, instanceParam);
@@ -39,59 +38,54 @@ namespace Encompass
         {
             foreach (var type in _componentTypes)
             {
-                CallGenericWrappedMethod(type, "CallAllComponentMethods", null);
+                CallGenericMethod(type, "ReadComponent", null);
+                CallGenericMethod(type, "ReadComponentIncludingEntity", null);
+                CallGenericMethod(type, "ReadComponents", null);
+                CallGenericMethod(type, "ReadComponentsIncludingEntity", null);
+                CallGenericMethod(type, "ReadEntity", null);
+                CallGenericMethod(type, "ReadEntities", null);
+                CallGenericMethod(type, "GetComponent", new Type[] { typeof(Entity) }, new object[] { Entity });
+                CallGenericMethod(type, "HasComponent", new Type[] { typeof(Entity) }, new object[] { Entity });
+                CallGenericMethod(type, "SomeComponent", null);
+                CallGenericMethod(type, "DestroyWith", null);
+                CallGenericMethod(type, "DestroyAllWith", null);
+                CallGenericMethod(type, "RemoveComponent", new Type[] { typeof(Entity) }, new object[] { Entity });
             }
 
             foreach (var type in _messageTypes)
             {
-                CallGenericWrappedMethod(type, "CallAllMessageMethods", null);
+                CallGenericMethod(type, "SendMessageIgnoringTimeDilation", new object[] { Activator.CreateInstance(type), 1 });
-
+                CallGenericMethod(type, "SendMessage", 1, new object[] { Activator.CreateInstance(type) });
+                CallGenericMethod(type, "SendMessage", 2, new object[] { Activator.CreateInstance(type), 1 });
+                CallGenericMethod(type, "ReadMessage", null);
+                CallGenericMethod(type, "ReadMessages", null);
+                CallGenericMethod(type, "SomeMessage", null);
                 if (typeof(IHasEntity).IsAssignableFrom(type))
                 {
-                    CallGenericWrappedMethod(type, "CallAllEntityMessageMethods", null);
+                    CallGenericMethod(type, "ReadMessagesWithEntity", new Type[] { typeof(Entity) }, new object[] { Entity });
                 }
             }
         }
 
-        // we can't reflect invoke on byref returns or Span returns right now... so we have non-return wrapper methods
+        private void CallGenericMethod(Type type, string methodName, object[] parameters)
-
-        protected void CallAllComponentMethods<TComponent>() where TComponent : struct
         {
-            ReadComponent<TComponent>();
+            var readComponentMethod = typeof(Engine).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
-            ReadComponents<TComponent>();
-            ReadEntity<TComponent>();
-            ReadEntities<TComponent>();
-            GetComponent<TComponent>(Entity);
-            HasComponent<TComponent>(Entity);
-            SomeComponent<TComponent>();
-            DestroyWith<TComponent>();
-            DestroyAllWith<TComponent>();
-            RemoveComponent<TComponent>(Entity);
-            AddComponent<TComponent>(Entity, default);
-        }
-
-        protected void CallAllMessageMethods<TMessage>() where TMessage : struct
-        {
-            SendMessageIgnoringTimeDilation<TMessage>(default, 0.1);
-            SendMessage<TMessage>(default);
-            SendMessage<TMessage>(default, 0.1);
-            ReadMessage<TMessage>();
-            ReadMessages<TMessage>();
-            SomeMessage<TMessage>();
-        }
-
-        protected void CallAllEntityMessageMethods<TMessage>() where TMessage : struct, IHasEntity
-        {
-            ReadMessagesWithEntity<TMessage>(Entity);
-            ReadMessageWithEntity<TMessage>(Entity);
-            SomeMessageWithEntity<TMessage>(Entity);
-        }
-
-        private void CallGenericWrappedMethod(Type type, string methodName, object[] parameters)
-        {
-            var readComponentMethod = typeof(UberEngine).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
             var genericReadComponentMethod = readComponentMethod.MakeGenericMethod(type);
             genericReadComponentMethod.Invoke(this, parameters);
         }
+
+        private void CallGenericMethod(Type type, string methodName, Type[] types, object[] parameters)
+        {
+            var readComponentMethod = typeof(Engine).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance, null, types, null);
+            var genericReadComponentMethod = readComponentMethod.MakeGenericMethod(type);
+            genericReadComponentMethod.Invoke(this, parameters);
+        }
+
+        private void CallGenericMethod(Type type, string methodName, int argumentNum, object[] parameters)
+        {
+            var method = typeof(Engine).GetRuntimeMethods().Where(m => m.Name == methodName && m.GetParameters().Length == argumentNum).First();
+            var genericMethod = method.MakeGenericMethod(type);
+            genericMethod.Invoke(this, parameters);
+        }
     }
 }

encompass-cs/UberRenderer.cs

@@ -6,7 +6,7 @@ namespace Encompass
 {
     class UberRenderer : Renderer
     {
-        private readonly IEnumerable<Type> _componentTypes;
+        private IEnumerable<Type> _componentTypes;
         private Entity _entity;
 
         public UberRenderer(IEnumerable<Type> componentTypes)
@@ -19,29 +19,25 @@ namespace Encompass
             _entity = entity;
         }
 
-        // can't reflect invoke on Span returns...
+        public void Render()
-        public override void Render(double dt, double alpha)
         {
             foreach (var type in _componentTypes)
             {
-                CallGenericWrappedMethod(type, "CallAllComponentMethods", null);
+                CallGenericMethod(type, "ReadEntities", null);
+                CallGenericMethod(type, "ReadEntity", null);
+                CallGenericMethod(type, "ReadComponent", null);
+                CallGenericMethod(type, "ReadComponentIncludingEntity", null);
+                CallGenericMethod(type, "ReadComponents", null);
+                CallGenericMethod(type, "ReadComponentsIncludingEntity", null);
+                CallGenericMethod(type, "GetComponent", new object[] { _entity });
+                CallGenericMethod(type, "HasComponent", new object[] { _entity });
+                CallGenericMethod(type, "SomeComponent", null);
             }
         }
 
-        protected void CallAllComponentMethods<TComponent>() where TComponent : struct
+        private void CallGenericMethod(Type type, string methodName, object[] parameters)
         {
-            ReadEntity<TComponent>();
+            var readComponentMethod = typeof(Renderer).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
-            ReadEntities<TComponent>();
-            ReadComponent<TComponent>();
-            ReadComponents<TComponent>();
-            GetComponent<TComponent>(_entity);
-            HasComponent<TComponent>(_entity);
-            SomeComponent<TComponent>();
-        }
-
-        private void CallGenericWrappedMethod(Type type, string methodName, object[] parameters)
-        {
-            var readComponentMethod = typeof(UberRenderer).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
             var genericReadComponentMethod = readComponentMethod.MakeGenericMethod(type);
             genericReadComponentMethod.Invoke(this, parameters);
         }

encompass-cs/World.cs

@@ -7,13 +7,13 @@ namespace Encompass
     /// </summary>
     public class World
     {
-        private readonly List<Engine> _enginesInOrder;
+        private readonly List<Engine> enginesInOrder;
-        private readonly EntityManager _entityManager;
+        private readonly EntityManager entityManager;
-        private readonly ComponentManager _componentManager;
+        private readonly ComponentManager componentManager;
-        private readonly TrackingManager _trackingManager;
+        private readonly TrackingManager trackingManager;
-        private readonly MessageManager _messageManager;
+        private readonly MessageManager messageManager;
-        private readonly TimeManager _timeManager;
+        private readonly TimeManager timeManager;
-        private readonly RenderManager _renderManager;
+        private readonly RenderManager renderManager;
 
         internal World(
             List<Engine> enginesInOrder,
@@ -25,13 +25,13 @@ namespace Encompass
             RenderManager renderManager
         )
         {
-            _enginesInOrder = enginesInOrder;
+            this.enginesInOrder = enginesInOrder;
-            _entityManager = entityManager;
+            this.entityManager = entityManager;
-            _componentManager = componentManager;
+            this.componentManager = componentManager;
-            _trackingManager = trackingManager;
+            this.trackingManager = trackingManager;
-            _messageManager = messageManager;
+            this.messageManager = messageManager;
-            _timeManager = timeManager;
+            this.timeManager = timeManager;
-            _renderManager = renderManager;
+            this.renderManager = renderManager;
         }
 
         /// <summary>
@@ -40,15 +40,15 @@ namespace Encompass
         /// <param name="dt">The time in seconds that has passed since the previous frame.</param>
         public void Update(double dt)
         {
-            _trackingManager.UpdateTracking();
+            trackingManager.UpdateTracking();
-            _messageManager.ProcessDelayedMessages(dt);
+            messageManager.ProcessDelayedMessages(dt);
-            _timeManager.Update(dt);
+            timeManager.Update(dt);
 
-            foreach (var engine in _enginesInOrder)
+            foreach (var engine in enginesInOrder)
             {
-                if (engine._usesTimeDilation)
+                if (engine.usesTimeDilation)
                 {
-                    engine.Update(dt * _timeManager.TimeDilationFactor);
+                    engine.Update(dt * timeManager.TimeDilationFactor);
                 }
                 else
                 {
@@ -58,20 +58,20 @@ namespace Encompass
                 engine.ClearNewlyCreatedEntities();
             }
 
-            _messageManager.ClearMessages();
+            messageManager.ClearMessages();
-            _entityManager.PruneEmptyEntities();
+            entityManager.PruneEmptyEntities();
-            _entityManager.DestroyMarkedEntities(_enginesInOrder);
+            entityManager.DestroyMarkedEntities(enginesInOrder);
 
-            _componentManager.RemoveMarkedComponents();
+            componentManager.RemoveMarkedComponents();
-            _componentManager.WriteComponents();
+            componentManager.WriteComponents();
         }
 
         /// <summary>
         /// Causes the Renderers to draw.
         /// </summary>
-        public void Draw(double dt, double alpha)
+        public void Draw()
         {
-            _renderManager.Draw(dt, alpha);
+            renderManager.Draw();
         }
     }
 }

encompass-cs/WorldBuilder.cs

@@ -3,6 +3,8 @@ using System.Collections.Generic;
 using System.Reflection;
 using System.Linq;
 using Encompass.Exceptions;
+using MoonTools.Core.Graph;
+using MoonTools.Core.Graph.Extensions;
 
 namespace Encompass
 {
@@ -16,37 +18,43 @@ namespace Encompass
     /// </remarks>
     public class WorldBuilder
     {
-        private readonly int _entityCapacity;
+        private readonly int entityCapacity;
-        private readonly List<Engine> _engines = new List<Engine>();
+        private readonly List<Engine> engines = new List<Engine>();
-        private readonly DirectedGraph<Engine> _engineGraph = new DirectedGraph<Engine>();
+        private readonly DirectedGraph<Engine, Unit> engineGraph = GraphBuilder.DirectedGraph<Engine>();
-        private readonly ComponentStore _startingExistingComponentStore;
+        private readonly ComponentStore startingExistingComponentStore;
-        private readonly ComponentStore _startingUpToDateComponentStore;
+        private readonly ComponentStore startingUpToDateComponentStore;
 
-        private readonly ComponentManager _componentManager;
+        private readonly ComponentManager componentManager;
-        private readonly EntityManager _entityManager;
+        private readonly EntityManager entityManager;
-        private readonly MessageManager _messageManager;
+        private readonly MessageManager messageManager;
-        private readonly TimeManager _timeManager;
+        private readonly TimeManager timeManager;
-        private readonly RenderManager _renderManager;
+        private readonly DrawLayerManager drawLayerManager;
-        private readonly TrackingManager _trackingManager;
+        private readonly RenderManager renderManager;
+        private readonly TrackingManager trackingManager;
 
-        private readonly Dictionary<Type, HashSet<Engine>> _typeToReaders = new Dictionary<Type, HashSet<Engine>>();
+        private readonly Dictionary<Type, HashSet<Engine>> typeToReaders = new Dictionary<Type, HashSet<Engine>>();
-        private readonly HashSet<Engine> _senders = new HashSet<Engine>();
+
-        private readonly HashSet<Type> _componentTypesToPreload = new HashSet<Type>();
+        private readonly HashSet<Engine> senders = new HashSet<Engine>();
-        private readonly HashSet<Type> _messageTypes = new HashSet<Type>();
+
-        private readonly Dictionary<Type, int> _typeToIndex = new Dictionary<Type, int>();
+        private readonly HashSet<Type> componentTypesToPreload = new HashSet<Type>();
+
+        private readonly HashSet<Type> messageTypes = new HashSet<Type>();
+
+        private readonly Dictionary<Type, int> typeToIndex = new Dictionary<Type, int>();
 
         public WorldBuilder(int entityCapacity = 32768)
         {
-            _entityCapacity = entityCapacity;
+            this.entityCapacity = entityCapacity;
-            _timeManager = new TimeManager();
+            drawLayerManager = new DrawLayerManager(typeToIndex);
-            _trackingManager = new TrackingManager();
+            timeManager = new TimeManager();
-            _componentManager = new ComponentManager(_typeToIndex);
+            trackingManager = new TrackingManager();
-            _messageManager = new MessageManager(_timeManager);
+            componentManager = new ComponentManager(drawLayerManager, typeToIndex);
-            _entityManager = new EntityManager(_componentManager, entityCapacity);
+            messageManager = new MessageManager(timeManager);
-            _renderManager = new RenderManager(_entityManager);
+            entityManager = new EntityManager(componentManager, entityCapacity);
+            renderManager = new RenderManager(entityManager, drawLayerManager);
 
-            _startingExistingComponentStore = new ComponentStore(_typeToIndex);
+            startingExistingComponentStore = new ComponentStore(typeToIndex);
-            _startingUpToDateComponentStore = new ComponentStore(_typeToIndex);
+            startingUpToDateComponentStore = new ComponentStore(typeToIndex);
         }
 
         /// <summary>
@@ -54,57 +62,56 @@ namespace Encompass
         /// </summary>
         public Entity CreateEntity()
         {
-            return _entityManager.CreateEntity();
+            return entityManager.CreateEntity();
         }
 
         /// <summary>
         /// Specifies that the given Message should be sent immediately on the first World Update.
         /// </summary>
-        public void SendMessage<TMessage>(in TMessage message) where TMessage : struct
+        public void SendMessage<TMessage>(TMessage message) where TMessage : struct, IMessage
         {
-            _messageManager.AddMessage(message);
+            messageManager.AddMessage(message);
         }
 
         /// <summary>
         /// Specifies that the given Message should be sent after the specified number of seconds after the first World Update.
         /// </summary>
-        public void SendMessage<TMessage>(in TMessage message, double time) where TMessage : struct
+        public void SendMessage<TMessage>(TMessage message, double time) where TMessage : struct, IMessage
         {
-            _messageManager.AddMessage<TMessage>(message, time);
+            messageManager.AddMessage<TMessage>(message, time);
         }
 
         /// <summary>
         /// Sets Component data for the specified Component Type on the specified Entity.
         /// </summary>
-        public void SetComponent<TComponent>(Entity entity, in TComponent component) where TComponent : struct
+        public void SetComponent<TComponent>(Entity entity, TComponent component) where TComponent : struct, IComponent
         {
             RegisterComponentType<TComponent>();
-            _startingExistingComponentStore.Set(entity.ID, component);
+            startingExistingComponentStore.Set(entity.ID, component);
-            _startingUpToDateComponentStore.Set(entity.ID, component);
+            startingUpToDateComponentStore.Set(entity.ID, component);
-        }
 
-        internal void RegisterComponentTypeNonGeneric(Type type)
+            if (component is IDrawableComponent drawableComponent)
-        {
-            var method = GetType().GetMethod("RegisterComponentType", BindingFlags.NonPublic | BindingFlags.Instance);
-            var generic = method.MakeGenericMethod(type);
-            generic.Invoke(this, null);
-        }
-
-        internal void RegisterComponentType<TComponent>() where TComponent : struct
-        {
-            if (!_typeToIndex.ContainsKey(typeof(TComponent)))
             {
-                _typeToIndex.Add(typeof(TComponent), _typeToIndex.Count);
+                componentManager.RegisterDrawableComponent(entity.ID, component, drawableComponent.Layer);
-                _componentTypesToPreload.Add(typeof(TComponent));
+                drawLayerManager.RegisterOrderedDrawable<TComponent>();
-                _componentManager.RegisterComponentType<TComponent>();
+            }
-                _startingExistingComponentStore.RegisterComponentType<TComponent>();
+        }
-                _startingUpToDateComponentStore.RegisterComponentType<TComponent>();
+
+        internal void RegisterComponentType<TComponent>() where TComponent : struct, IComponent
+        {
+            if (!typeToIndex.ContainsKey(typeof(TComponent)))
+            {
+                typeToIndex.Add(typeof(TComponent), typeToIndex.Count);
+                componentTypesToPreload.Add(typeof(TComponent));
+                componentManager.RegisterComponentType<TComponent>();
+                startingExistingComponentStore.RegisterComponentType<TComponent>();
+                startingUpToDateComponentStore.RegisterComponentType<TComponent>();
             }
         }
 
         internal void RegisterMessageTypes(IEnumerable<Type> types)
         {
-            _messageTypes.UnionWith(types);
+            messageTypes.UnionWith(types);
         }
 
         /// <summary>
@@ -113,151 +120,109 @@ namespace Encompass
         /// <param name="engine">An instance of an Engine.</param>
         public Engine AddEngine<TEngine>(TEngine engine) where TEngine : Engine
         {
-            engine.AssignEntityManager(_entityManager);
+            engine.AssignEntityManager(entityManager);
-            engine.AssignComponentManager(_componentManager);
+            engine.AssignComponentManager(componentManager);
-            engine.AssignMessageManager(_messageManager);
+            engine.AssignMessageManager(messageManager);
-            engine.AssignTimeManager(_timeManager);
+            engine.AssignTimeManager(timeManager);
-            engine.AssignTrackingManager(_trackingManager);
+            engine.AssignTrackingManager(trackingManager);
 
-            _engines.Add(engine);
+            engines.Add(engine);
-            _engineGraph.AddNode(engine);
+            engineGraph.AddNode(engine);
 
-            var messageReceiveTypes = engine.ReceiveTypes;
+            var messageReceiveTypes = engine.receiveTypes;
-            var messageSendTypes = engine.SendTypes;
+            var messageSendTypes = engine.sendTypes;
 
-            RegisterMessageTypes(engine.ReceiveTypes);
+            RegisterMessageTypes(engine.receiveTypes.Union(engine.sendTypes));
-            RegisterMessageTypes(engine.SendTypes);
 
-            foreach (var writeImmediateType in engine.WriteImmediateTypes)
+            foreach (var writeImmediateType in engine.writeImmediateTypes.Intersect(engine.readImmediateTypes))
             {
-                foreach (var readImmediateType in engine.ReadImmediateTypes)
+                throw new EngineSelfCycleException("Engine {0} both writes and reads immediate Component {1}", engine.GetType().Name, writeImmediateType.Name);
+            }
+
+            foreach (var messageType in messageReceiveTypes.Intersect(messageSendTypes))
+            {
+                throw new EngineSelfCycleException("Engine {0} both receives and sends Message {1}", engine.GetType().Name, messageType.Name);
+            }
+
+            if (messageSendTypes.Count > 0 || engine.writeImmediateTypes.Count > 0)
+            {
+                senders.Add(engine);
+            }
+
+            foreach (var componentType in engine.queryWithTypes.Union(engine.queryWithoutTypes))
+            {
+                trackingManager.RegisterComponentTypeToEngine(componentType, engine);
+                if (engine.readImmediateTypes.Contains(componentType))
                 {
-                    if (readImmediateType == writeImmediateType)
+                    trackingManager.RegisterImmediateComponentTypeToEngine(componentType, engine);
-                    {
-                        throw new EngineSelfCycleException("Engine {0} both writes and reads immediate Component {1}", engine.GetType().Name, writeImmediateType.Name);
-                    }
                 }
             }
 
-            foreach (var messageReceiveType in messageReceiveTypes)
+            foreach (var receiveType in engine.receiveTypes.Union(engine.readImmediateTypes))
             {
-                foreach (var messageSendType in messageSendTypes)
+                if (!typeToReaders.ContainsKey(receiveType))
                 {
-                    if (messageReceiveType == messageSendType)
+                    typeToReaders.Add(receiveType, new HashSet<Engine>());
-                    {
-                        throw new EngineSelfCycleException("Engine {0} both receives and sends Message {1}", engine.GetType().Name, messageReceiveType.Name);
-                    }
-                }
-            }
-
-            if (messageSendTypes.Count > 0 || engine.WriteImmediateTypes.Count > 0)
-            {
-                _senders.Add(engine);
-            }
-
-            foreach (var componentType in engine.ReadTypes)
-            {
-                RegisterComponentTypeNonGeneric(componentType);
-            }
-
-            foreach (var componentType in engine.AddTypes)
-            {
-                RegisterComponentTypeNonGeneric(componentType);
-            }
-
-            foreach (var componentType in engine.WriteTypes)
-            {
-                RegisterComponentTypeNonGeneric(componentType);
-            }
-
-            foreach (var componentType in engine.WriteImmediateTypes)
-            {
-                RegisterComponentTypeNonGeneric(componentType);
-            }
-
-            foreach (var componentType in engine.QueryWithTypes)
-            {
-                _trackingManager.RegisterComponentTypeToEngine(componentType, engine);
-                if (engine.ReadImmediateTypes.Contains(componentType))
-                {
-                    _trackingManager.RegisterImmediateComponentTypeToEngine(componentType, engine);
-                }
-            }
-
-            foreach (var componentType in engine.QueryWithoutTypes)
-            {
-                _trackingManager.RegisterComponentTypeToEngine(componentType, engine);
-                if (engine.ReadImmediateTypes.Contains(componentType))
-                {
-                    _trackingManager.RegisterImmediateComponentTypeToEngine(componentType, engine);
-                }
-            }
-
-            foreach (var receiveType in engine.ReceiveTypes)
-            {
-                if (!_typeToReaders.ContainsKey(receiveType))
-                {
-                    _typeToReaders.Add(receiveType, new HashSet<Engine>());
                 }
 
-                _typeToReaders[receiveType].Add(engine);
+                typeToReaders[receiveType].Add(engine);
-            }
-
-            foreach (var receiveType in engine.ReadImmediateTypes)
-            {
-                if (!_typeToReaders.ContainsKey(receiveType))
-                {
-                    _typeToReaders.Add(receiveType, new HashSet<Engine>());
-                }
-
-                _typeToReaders[receiveType].Add(engine);
             }
 
             return engine;
         }
 
         /// <summary>
-        /// Adds the specified Renderer to the World.
+        /// Registers a draw layer. This must be done before any Renderers are registered.
         /// </summary>
-        public void AddRenderer(Renderer renderer)
+        /// <param name="layer">The draw layer to register.</param>
+        public void RegisterDrawLayer(int layer)
         {
-            renderer.AssignComponentManager(_componentManager);
+            drawLayerManager.RegisterDrawLayer(layer);
-            renderer.AssignEntityManager(_entityManager);
+        }
-            _renderManager.AddRenderer(renderer);
+
+        /// <summary>
+        /// Adds the specified OrderedRenderer to the World.
+        /// </summary>
+        public OrderedRenderer<TComponent> AddOrderedRenderer<TComponent>(OrderedRenderer<TComponent> renderer) where TComponent : struct, IComponent, IDrawableComponent
+        {
+            RegisterComponentType<TComponent>();
+            renderer.AssignEntityManager(entityManager);
+            renderer.AssignComponentManager(componentManager);
+            renderManager.RegisterOrderedRenderer<TComponent>(renderer.InternalRender);
+            return renderer;
+        }
+
+        /// <summary>
+        /// Adds the specified GeneralRenderer to the World at the specified layer.
+        /// Higher layer numbers draw on top of lower layer numbers.
+        /// </summary>
+        /// <param name="renderer">An instance of a GeneralRenderer.</param>
+        /// <param name="layer">The layer at which the GeneralRenderer should render. Higher numbers draw over lower numbers.</param>
+        public TRenderer AddGeneralRenderer<TRenderer>(TRenderer renderer, int layer) where TRenderer : GeneralRenderer
+        {
+            renderer.AssignEntityManager(entityManager);
+            renderer.AssignComponentManager(componentManager);
+
+            renderManager.RegisterGeneralRendererWithLayer(renderer, layer);
+
+            return renderer;
         }
 
         private void BuildEngineGraph()
         {
-            foreach (var senderEngine in _senders)
+            foreach (var senderEngine in senders)
             {
-                foreach (var messageType in senderEngine.SendTypes)
+                foreach (var messageType in senderEngine.sendTypes.Union(senderEngine.writeImmediateTypes))
                 {
-                    if (_typeToReaders.ContainsKey(messageType))
+                    if (typeToReaders.ContainsKey(messageType))
                     {
-                        foreach (var readerEngine in _typeToReaders[messageType])
+                        foreach (var readerEngine in typeToReaders[messageType])
                         {
                             if (senderEngine != readerEngine)
                             {
-                                if (!_engineGraph.Exists(senderEngine, readerEngine))
+                                if (!engineGraph.Exists(senderEngine, readerEngine))
                                 {
-                                    _engineGraph.AddEdge(senderEngine, readerEngine);
+                                    engineGraph.AddEdge(senderEngine, readerEngine);
-                                }
-                            }
-                        }
-                    }
-                }
-
-                foreach (var messageType in senderEngine.WriteImmediateTypes)
-                {
-                    if (_typeToReaders.ContainsKey(messageType))
-                    {
-                        foreach (var readerEngine in _typeToReaders[messageType])
-                        {
-                            if (senderEngine != readerEngine)
-                            {
-                                if (!_engineGraph.Exists(senderEngine, readerEngine))
-                                {
-                                    _engineGraph.AddEdge(senderEngine, readerEngine);
                                 }
                             }
                         }
@@ -275,9 +240,9 @@ namespace Encompass
         {
             BuildEngineGraph();
 
-            if (_engineGraph.Cyclic())
+            if (engineGraph.Cyclic())
             {
-                var cycles = _engineGraph.SimpleCycles();
+                var cycles = engineGraph.SimpleCycles();
                 var errorString = "Cycle(s) found in Engines: ";
                 foreach (var cycle in cycles)
                 {
@@ -297,25 +262,25 @@ namespace Encompass
             var writePriorities = new Dictionary<Type, HashSet<int>>();
             var writeMessageToEngines = new Dictionary<Type, List<Engine>>();
 
-            foreach (var engine in _engines)
+            foreach (var engine in engines)
             {
                 if (engine.GetType().GetCustomAttribute<IgnoresTimeDilation>() != null)
                 {
-                    engine._usesTimeDilation = false;
+                    engine.usesTimeDilation = false;
                 }
 
                 var defaultWritePriorityAttribute = engine.GetType().GetCustomAttribute<DefaultWritePriority>(false);
 
-                foreach (var writeType in engine.WriteTypes)
+                foreach (var writeType in engine.writeTypes)
                 {
                     int? priority = null;
-                    if (engine.WritePriorities.ContainsKey(writeType))
+                    if (engine.writePriorities.ContainsKey(writeType))
                     {
-                        priority = engine.WritePriorities[writeType];
+                        priority = engine.writePriorities[writeType];
                     }
                     else if (defaultWritePriorityAttribute != null)
                     {
-                        priority = defaultWritePriorityAttribute.WritePriority;
+                        priority = defaultWritePriorityAttribute.writePriority;
                     }
 
                     if (priority.HasValue)
@@ -389,11 +354,25 @@ namespace Encompass
                 throw new EngineWriteConflictException(errorString);
             }
 
-            PreloadJIT(_messageTypes);
+            // doing reflection to grab all component types, because not all writes need to be declared
+            foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
+            {
+                foreach (var componentType in assembly.GetTypes())
+                {
+                    if (typeof(IComponent).IsAssignableFrom(componentType) && componentType.IsValueType && !componentType.IsEnum && !componentType.IsPrimitive)
+                    {
+                        var method = typeof(WorldBuilder).GetMethod("RegisterComponentType", BindingFlags.NonPublic | BindingFlags.Instance);
+                        var generic = method.MakeGenericMethod(componentType);
+                        generic.Invoke(this, null);
+                    }
+                }
+            }
+
+            PreloadJIT(componentTypesToPreload, messageTypes);
 
             var engineOrder = new List<Engine>();
 
-            foreach (var engine in _engineGraph.TopologicalSort())
+            foreach (var engine in engineGraph.TopologicalSort())
             {
                 engineOrder.Add(engine);
                 engine.BuildEntityQuery();
@@ -401,18 +380,18 @@ namespace Encompass
 
             var world = new World(
                 engineOrder,
-                _entityManager,
+                entityManager,
-                _componentManager,
+                componentManager,
-                _trackingManager,
+                trackingManager,
-                _messageManager,
+                messageManager,
-                _timeManager,
+                timeManager,
-                _renderManager
+                renderManager
             );
 
-            _componentManager.SetExistingComponentStore(_startingExistingComponentStore);
+            componentManager.SetExistingComponentStore(startingExistingComponentStore);
-            _componentManager.SetUpToDateComponentStore(_startingUpToDateComponentStore);
+            componentManager.SetUpToDateComponentStore(startingUpToDateComponentStore);
 
-            _trackingManager.InitializeTracking(_entityManager.EntityIDs);
+            trackingManager.InitializeTracking(entityManager.EntityIDs);
 
             return world;
         }
@@ -423,25 +402,19 @@ namespace Encompass
         /// It does so by grabbing all component and message types known to the WorldBuilder and
         /// executing every possible generic method that could be executed with those types.
         /// </summary>
-        private void PreloadJIT(IEnumerable<Type> messageTypes)
+        private void PreloadJIT(IEnumerable<Type> componentTypes, IEnumerable<Type> messageTypes)
         {
             var dummyTimeManager = new TimeManager();
             var dummyMessageManager = new MessageManager(dummyTimeManager);
+            var dummyDrawLayerManager = new DrawLayerManager(typeToIndex);
             var dummyTrackingManager = new TrackingManager();
-            var dummyComponentManager = new ComponentManager(_typeToIndex);
+            var dummyComponentManager = new ComponentManager(dummyDrawLayerManager, typeToIndex);
-            var dummyEntityManager = new EntityManager(dummyComponentManager, _entityCapacity);
+            var dummyEntityManager = new EntityManager(dummyComponentManager, entityCapacity);
-            var dummyRenderManager = new RenderManager(dummyEntityManager);
+            var dummyRenderManager = new RenderManager(dummyEntityManager, dummyDrawLayerManager);
 
             var prepEngineOrder = new List<Engine>();
 
-            foreach (var componentType in _componentTypesToPreload)
+            var uberEngine = new UberEngine(componentTypes, messageTypes);
-            {
-                var dummyRegisterMethod = typeof(ComponentManager).GetMethod("RegisterComponentType", BindingFlags.Public | BindingFlags.Instance);
-                var dummyGeneric = dummyRegisterMethod.MakeGenericMethod(componentType);
-                dummyGeneric.Invoke(dummyComponentManager, null);
-            }
-
-            var uberEngine = new UberEngine(_componentTypesToPreload, messageTypes);
 
             uberEngine.AssignEntityManager(dummyEntityManager);
             uberEngine.AssignComponentManager(dummyComponentManager);
@@ -449,10 +422,24 @@ namespace Encompass
             uberEngine.AssignTimeManager(dummyTimeManager);
             uberEngine.AssignTrackingManager(dummyTrackingManager);
 
-            var uberRenderer = new UberRenderer(_componentTypesToPreload);
+            var uberRenderer = new UberRenderer(componentTypes);
             uberRenderer.AssignComponentManager(dummyComponentManager);
             uberRenderer.AssignEntityManager(dummyEntityManager);
 
+            foreach (var type in componentTypes)
+            {
+                var componentManagerRegisterMethod = typeof(ComponentManager).GetMethod("RegisterComponentType");
+                var componentManagerRegisterGenericMethod = componentManagerRegisterMethod.MakeGenericMethod(type);
+                componentManagerRegisterGenericMethod.Invoke(dummyComponentManager, null);
+
+                if (type.GetInterface("IDrawableComponent") != null)
+                {
+                    var drawLayerManagerRegisterMethod = typeof(DrawLayerManager).GetMethod("RegisterOrderedDrawable");
+                    var drawLayerManagerRegisterGenericMethod = drawLayerManagerRegisterMethod.MakeGenericMethod(type);
+                    drawLayerManagerRegisterGenericMethod.Invoke(dummyDrawLayerManager, null);
+                }
+            }
+
             prepEngineOrder.Add(uberEngine);
 
             var dummyWorld = new World(
@@ -474,7 +461,7 @@ namespace Encompass
             dummyComponentManager.WriteComponents();
 
             uberRenderer.SetEntity(uberEngine.Entity);
-            uberRenderer.Render(1, 0);
+            uberRenderer.Render();
         }
     }
 }

encompass-cs/encompass-cs.csproj

@@ -1,23 +1,20 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>8.0</LangVersion>
-    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <RootNamespace>Encompass</RootNamespace>
     <PackageId>EncompassECS.Framework</PackageId>
-    <Version>0.23.0</Version>
+    <Version>0.20.0</Version>
     <Authors>Evan Hemsley</Authors>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
     <Company>Moonside Games</Company>
     <Product>Encompass ECS</Product>
     <PackageProjectUrl>https://github.com/encompass-ecs</PackageProjectUrl>
     <PackageLicenseUrl />
-    <Copyright>Evan Hemsley 2020</Copyright>
+    <Copyright>Evan Hemsley 2019</Copyright>
-    <Description>Encompass is an engine-agnostic MECS framework to help you code games, or other kinds of simulations.</Description>
+    <Description>Encompass is an engine-agnostic Hyper ECS framework to help you code games, or other kinds of simulations.</Description>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <AssemblyName>EncompassECS.Framework</AssemblyName>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
-    <Platforms>x64;x86</Platforms>
   </PropertyGroup>
   <ItemGroup>
     <None Include="..\LICENSE">
@@ -26,7 +23,8 @@
     </None>
   </ItemGroup>
   <ItemGroup>
+    <PackageReference Include="MoonTools.Core.Graph" Version="1.0.0" />
+    <PackageReference Include="MoonTools.FastCollections" Version="1.0.0" />
     <PackageReference Include="System.Collections.Immutable" Version="1.7.0" />
-    <PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.0" />
   </ItemGroup>
 </Project>

test/ComponentTest.cs

@@ -2,18 +2,18 @@ using NUnit.Framework;
 using FluentAssertions;
 
 using Encompass;
-using System.Runtime.CompilerServices;
 
 namespace Tests
 {
     public class ComponentTests
     {
-        struct MockComponent
+        struct MockComponent : Encompass.IComponent
         {
+            public string myString;
             public int myInt;
         }
 
-        struct EntityMessage
+        struct EntityMessage : IMessage
         {
             public Entity entity;
         }
@@ -26,14 +26,14 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entityMessage in ReadMessages<EntityMessage>())
+                foreach (var entityMessage in ReadMessages<EntityMessage>())
                 {
                     gottenMockComponent = GetComponent<MockComponent>(entityMessage.entity);
                 }
             }
         }
 
-        struct AddComponentTestMessage
+        struct AddComponentTestMessage : IMessage
         {
             public Entity entity;
             public MockComponent mockComponent;
@@ -45,17 +45,16 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var addComponentTestMessage in ReadMessages<AddComponentTestMessage>())
+                foreach (var addComponentTestMessage in ReadMessages<AddComponentTestMessage>())
                 {
                     Assert.IsTrue(HasComponent<MockComponent>(addComponentTestMessage.entity));
-                    ref readonly var gottenComponent = ref GetComponent<MockComponent>(addComponentTestMessage.entity);
+                    Assert.That(GetComponent<MockComponent>(addComponentTestMessage.entity), Is.EqualTo(addComponentTestMessage.mockComponent));
-                    gottenComponent.Should().BeEquivalentTo(addComponentTestMessage.mockComponent);
                 }
             }
         }
 
         [Test]
-        public unsafe void AddComponent()
+        public void AddComponent()
         {
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new AddComponentTestEngine());
@@ -64,6 +63,7 @@ namespace Tests
 
             MockComponent mockComponent;
             mockComponent.myInt = 3;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -85,15 +85,16 @@ namespace Tests
             worldBuilder.AddEngine(new ReadMockComponentEngine());
 
             var entity = worldBuilder.CreateEntity();
-            worldBuilder.SetComponent(entity, new MockComponent { myInt = 20 });
+            worldBuilder.SetComponent(entity, new MockComponent { myInt = 20, myString = "what" });
-            worldBuilder.SetComponent(entity, new MockComponent { myInt = 50 });
+            worldBuilder.SetComponent(entity, new MockComponent { myInt = 50, myString = "hi" });
-            worldBuilder.SetComponent(entity, new MockComponent { myInt = 40 });
+            worldBuilder.SetComponent(entity, new MockComponent { myInt = 40, myString = "wassup" });
 
             var world = worldBuilder.Build();
 
             world.Update(0.01);
 
             Assert.That(gottenMockComponent.myInt, Is.EqualTo(40));
+            Assert.That(gottenMockComponent.myString, Is.EqualTo("wassup"));
         }
 
         [Reads(typeof(MockComponent))]
@@ -102,9 +103,8 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                foreach (var (mockComponent, entity) in ReadComponentsIncludingEntity<MockComponent>())
                 {
-                    ref readonly var mockComponent = ref GetComponent<MockComponent>(entity);
                     SetComponent(entity, new MockComponent { myInt = mockComponent.myInt + 1 });
                 }
             }
@@ -149,9 +149,8 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                foreach (var (mockComponent, entity) in ReadComponentsIncludingEntity<MockComponent>())
                 {
-                    ref readonly var mockComponent = ref GetComponent<MockComponent>(entity);
                     SetComponent(entity, mockComponent);
                     RemoveComponent<MockComponent>(entity);
                 }
@@ -172,7 +171,7 @@ namespace Tests
             Assert.DoesNotThrow(() => world.Update(0.01));
         }
 
-        struct AddMockComponentMessage
+        struct AddMockComponentMessage : IMessage
         {
             public Entity entity;
             public MockComponent mockComponent;
@@ -192,6 +191,7 @@ namespace Tests
             {
                 MockComponent mockComponent;
                 mockComponent.myInt = 10;
+                mockComponent.myString = "four";
 
                 AddMockComponentMessage addMockComponentMessage;
                 addMockComponentMessage.entity = entity;
@@ -207,7 +207,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var message in ReadMessages<AddMockComponentMessage>())
+                foreach (var message in ReadMessages<AddMockComponentMessage>())
                 {
                     SetComponent(message.entity, message.mockComponent);
                 }
@@ -255,8 +255,9 @@ namespace Tests
 
             MockComponent mockComponent;
             mockComponent.myInt = 3;
+            mockComponent.myString = "hello";
 
-            worldBuilder.SetComponent(entity, mockComponent);
+            worldBuilder.SetComponent<MockComponent>(entity, mockComponent);
 
             EntityMessage entityMessage;
             entityMessage.entity = entity;
@@ -269,7 +270,7 @@ namespace Tests
 
             Assert.AreEqual(mockComponent, gottenMockComponent);
         }
-        struct HasComponentTestMessage
+        struct HasComponentTestMessage : IMessage
         {
             public Entity entity;
         }
@@ -280,7 +281,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var hasComponentTestEngine in ReadMessages<HasComponentTestMessage>())
+                foreach (var hasComponentTestEngine in ReadMessages<HasComponentTestMessage>())
                 {
                     Assert.IsTrue(HasComponent<MockComponent>(hasComponentTestEngine.entity));
                 }
@@ -297,6 +298,7 @@ namespace Tests
 
             MockComponent mockComponent;
             mockComponent.myInt = 3;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -317,7 +319,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var hasComponentTestEngine in ReadMessages<HasComponentTestMessage>())
+                foreach (var hasComponentTestEngine in ReadMessages<HasComponentTestMessage>())
                 {
                     hasComponentRuntimeTypeResult = HasComponent(hasComponentTestEngine.entity, typeof(MockComponent));
                 }
@@ -334,6 +336,7 @@ namespace Tests
 
             MockComponent mockComponent;
             mockComponent.myInt = 3;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -367,7 +370,7 @@ namespace Tests
             Assert.IsFalse(hasComponentRuntimeTypeResult);
         }
 
-        struct RemoveComponentTestMessage
+        struct RemoveComponentTestMessage : IMessage
         {
             public Entity entity;
         }
@@ -379,7 +382,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var removeComponentMessage in ReadMessages<RemoveComponentTestMessage>())
+                foreach (var removeComponentMessage in ReadMessages<RemoveComponentTestMessage>())
                 {
                     RemoveComponent<MockComponent>(removeComponentMessage.entity);
                 }
@@ -424,7 +427,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var checkHasMockComponentMessage in ReadMessages<CheckHasMockComponentMessage>())
+                foreach (var checkHasMockComponentMessage in ReadMessages<CheckHasMockComponentMessage>())
                 {
                     hasComponentResult = HasComponent<MockComponent>(checkHasMockComponentMessage.entity);
                 }
@@ -443,6 +446,7 @@ namespace Tests
 
             MockComponent mockComponent;
             mockComponent.myInt = 3;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -461,7 +465,7 @@ namespace Tests
             hasComponentResult.Should().BeFalse();
         }
 
-        struct CheckHasMockComponentMessage
+        struct CheckHasMockComponentMessage : IMessage
         {
             public Entity entity;
             public bool shouldHaveComponent;
@@ -473,7 +477,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var checkHasMockComponentMessage in ReadMessages<CheckHasMockComponentMessage>())
+                foreach (var checkHasMockComponentMessage in ReadMessages<CheckHasMockComponentMessage>())
                 {
                     Assert.IsTrue(HasComponent<MockComponent>(checkHasMockComponentMessage.entity));
                 }

test/EngineTest.cs

@@ -10,29 +10,29 @@ using Encompass.Exceptions;
 
 namespace Tests
 {
-    struct MockComponent
+    struct MockComponent : IComponent
     {
         public int myInt;
+        public string myString;
     }
 
     public class EngineTest
     {
+        static List<MockComponent> resultComponents;
         static MockComponent resultComponent;
-        static MockComponent[] resultComponents = new MockComponent[1];
 
-        static MockMessage resultMessage;
+        static List<MockMessage> resultMessages = new List<MockMessage>();
-        static MockMessage[] resultMessages = new MockMessage[1];
 
         [Reads(typeof(MockComponent))]
         public class ReadComponentsTestEngine : Engine
         {
             public override void Update(double dt)
             {
-                resultComponents = ReadComponents<MockComponent>().ToArray();
+                resultComponents = ReadComponents<MockComponent>().ToList();
             }
         }
 
-        static List<(MockComponent, Entity)> resultComponentsIncludingEntity = new List<(MockComponent, Entity)>();
+        static List<(MockComponent, Entity)> resultComponentsIncludingEntity;
         static (MockComponent, Entity) resultComponentIncludingEntity;
 
         [Reads(typeof(MockComponent))]
@@ -40,11 +40,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                resultComponentsIncludingEntity = ReadComponentsIncludingEntity<MockComponent>().ToList();
-                {
-                    ref readonly var mockComponent = ref GetComponent<MockComponent>(entity);
-                    resultComponentsIncludingEntity.Add((mockComponent, entity));
-                }
             }
         }
 
@@ -62,9 +58,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                ref readonly var entity = ref ReadEntity<MockComponent>();
+                resultComponentIncludingEntity = ReadComponentIncludingEntity<MockComponent>();
-                ref readonly var mockComponent = ref GetComponent<MockComponent>(entity);
-                resultComponentIncludingEntity = (mockComponent, entity);
             }
         }
 
@@ -78,10 +72,12 @@ namespace Tests
             var entityB = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 2;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             MockComponent mockComponentB;
             mockComponentB.myInt = 1;
+            mockComponentB.myString = "howdy";
 
             worldBuilder.SetComponent(entity, mockComponent);
             worldBuilder.SetComponent(entityB, mockComponentB);
@@ -97,8 +93,6 @@ namespace Tests
         [Test]
         public void ReadComponentsIncludingEntity()
         {
-            resultComponentsIncludingEntity.Clear();
-
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new ReadComponentsIncludingEntityEngine());
 
@@ -106,10 +100,12 @@ namespace Tests
             var entityB = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 2;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             MockComponent mockComponentB;
             mockComponentB.myInt = 1;
+            mockComponentB.myString = "howdy";
 
             worldBuilder.SetComponent(entity, mockComponent);
             worldBuilder.SetComponent(entityB, mockComponentB);
@@ -139,7 +135,8 @@ namespace Tests
             var entity = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 3;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -150,17 +147,6 @@ namespace Tests
             Assert.AreEqual(mockComponent, resultComponent);
         }
 
-        [Test]
-        public void ReadComponentThrowsWhenNoneExist()
-        {
-            var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine(new ReadComponentTestEngine());
-
-            var world = worldBuilder.Build();
-
-            Assert.Throws<NoComponentOfTypeException>(() => world.Update(0.01f), "No component of type MockComponent exists");
-        }
-
         [Test]
         public void ReadComponentWhenMultipleComponents()
         {
@@ -171,10 +157,12 @@ namespace Tests
             var entityB = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 2;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             MockComponent mockComponentB;
             mockComponentB.myInt = 1;
+            mockComponentB.myString = "howdy";
 
             worldBuilder.SetComponent(entity, mockComponent);
             worldBuilder.SetComponent(entityB, mockComponentB);
@@ -195,7 +183,8 @@ namespace Tests
             var entity = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 2;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -212,8 +201,11 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                ref readonly var entity = ref ReadEntity<MockComponent>();
+                var (component, entity) = ReadComponentIncludingEntity<MockComponent>();
-                SetComponent(entity, new MockComponent { myInt = 420 });
+
+                component.myInt = 420;
+                component.myString = "blaze it";
+                SetComponent(entity, component);
             }
         }
 
@@ -230,7 +222,8 @@ namespace Tests
             var entity = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 3;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -240,6 +233,7 @@ namespace Tests
             world.Update(0.01);
 
             Assert.AreEqual(420, resultComponent.myInt);
+            Assert.AreEqual("blaze it", resultComponent.myString);
         }
 
         [Reads(typeof(MockComponent))]
@@ -247,8 +241,13 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                ref readonly var entity = ref ReadEntity<MockComponent>();
+                var (component, entity) = ReadComponentIncludingEntity<MockComponent>();
-                SetComponent(entity, new MockComponent { myInt = 420 });
+
+                component.myInt = 420;
+                component.myString = "blaze it";
+                SetComponent(entity, component);
+
+                component = ReadComponent<MockComponent>();
             }
         }
 
@@ -261,7 +260,8 @@ namespace Tests
             var entity = worldBuilder.CreateEntity();
 
             MockComponent mockComponent;
-            mockComponent.myInt = 3;
+            mockComponent.myInt = 0;
+            mockComponent.myString = "hello";
 
             worldBuilder.SetComponent(entity, mockComponent);
 
@@ -271,7 +271,7 @@ namespace Tests
             Assert.That(ex.Message, Is.EqualTo("Engine UndeclaredUpdateComponentTestEngine tried to update undeclared Component MockComponent"));
         }
 
-        struct MockMessage
+        struct MockMessage : IMessage
         {
             public string myString;
         }
@@ -289,20 +289,11 @@ namespace Tests
         }
 
         [Receives(typeof(MockMessage))]
-        public class ReadMessagesEngine : Engine
+        public class MessageReadEngine : Engine
         {
             public override void Update(double dt)
             {
-                resultMessages = ReadMessages<MockMessage>().ToArray();
+                resultMessages = this.ReadMessages<MockMessage>().ToList();
-            }
-        }
-
-        [Receives(typeof(MockMessage))]
-        public class ReadMessageEngine : Engine
-        {
-            public override void Update(double dt)
-            {
-                resultMessage = ReadMessage<MockMessage>();
             }
         }
 
@@ -311,24 +302,13 @@ namespace Tests
         {
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new MessageEmitEngine());
-            worldBuilder.AddEngine(new ReadMessageEngine());
+            worldBuilder.AddEngine(new MessageReadEngine());
 
             var world = worldBuilder.Build();
 
             world.Update(0.01f);
 
-            Assert.AreEqual(resultMessage.myString, "howdy");
+            Assert.AreEqual(resultMessages.First().myString, "howdy");
-        }
-
-        [Test]
-        public void ReadMessageThrowsWhenNoneOfTypeExist()
-        {
-            var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine(new ReadMessageEngine());
-
-            var world = worldBuilder.Build();
-
-            Assert.Throws<NoMessageOfTypeException>(() => world.Update(0.01), "No Message of type MockMessage exists");
         }
 
         public class UndeclaredMessageEmitEngine : Engine
@@ -342,14 +322,14 @@ namespace Tests
             }
         }
 
-        static MockMessage[] emptyReadMessagesResult;
+        static IEnumerable<MockMessage> emptyReadMessagesResult;
 
         [Receives(typeof(MockMessage))]
         class ReadMessagesWhenNoneExistEngine : Engine
         {
             public override void Update(double dt)
             {
-                emptyReadMessagesResult = ReadMessages<MockMessage>().ToArray();
+                emptyReadMessagesResult = ReadMessages<MockMessage>();
             }
         }
 
@@ -435,7 +415,7 @@ namespace Tests
             Assert.Throws<IllegalReadException>(() => world.Update(0.01f));
         }
 
-        struct EntityMessage : IHasEntity
+        struct EntityMessage : IMessage, IHasEntity
         {
             public EntityMessage(Entity entity, int myInt)
             {
@@ -598,10 +578,10 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                var entities = ReadEntities<MockComponent>();
+                var components = ReadComponentsIncludingEntity<MockComponent>();
 
-                pairA = (GetComponent<MockComponent>(entities[0]), entities[0]);
+                pairA = components.First();
-                pairB = (GetComponent<MockComponent>(entities[1]), entities[1]);
+                pairB = components.Last();
             }
         }
 
@@ -614,9 +594,11 @@ namespace Tests
 
             MockComponent componentA;
             componentA.myInt = 20;
+            componentA.myString = "hello";
 
             MockComponent componentB;
             componentB.myInt = 20;
+            componentB.myString = "hello";
 
             var entity = worldBuilder.CreateEntity();
             worldBuilder.SetComponent(entity, componentA);
@@ -631,12 +613,14 @@ namespace Tests
             Assert.That(EngineTest.pairA.Item1, Is.EqualTo(EngineTest.pairB.Item1));
         }
 
+        static IEnumerable<(MockComponent, Entity)> emptyComponentReadResult;
+
         [Reads(typeof(MockComponent))]
         class ReadEmptyMockComponentsEngine : Engine
         {
             public override void Update(double dt)
             {
-                ReadEntities<MockComponent>().ToArray().Should().BeEmpty();
+                emptyComponentReadResult = ReadComponentsIncludingEntity<MockComponent>();
             }
         }
 
@@ -648,36 +632,32 @@ namespace Tests
 
             var world = worldBuilder.Build();
             world.Update(0.01f);
+
+            Assert.That(emptyComponentReadResult, Is.Empty);
         }
 
-        struct DestroyerComponent { }
+        struct DestroyerComponent : IComponent { }
 
         [Reads(typeof(DestroyerComponent))]
         class DestroyerEngine : Engine
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<DestroyerComponent>())
+                foreach (var (component, entity) in ReadComponentsIncludingEntity<DestroyerComponent>())
                 {
                     Destroy(entity);
                 }
             }
         }
 
-        static List<(MockComponent, Entity)> results = new List<(MockComponent, Entity)>();
+        static List<(MockComponent, Entity)> results;
 
         [Reads(typeof(MockComponent))]
         class ReaderEngine : Engine
         {
             public override void Update(double dt)
             {
-                results.Clear();
+                results = ReadComponentsIncludingEntity<MockComponent>().ToList();
-
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
-                {
-                    ref readonly var mockComponent = ref GetComponent<MockComponent>(entity);
-                    results.Add((mockComponent, entity));
-                }
             }
         }
 
@@ -695,6 +675,7 @@ namespace Tests
             DestroyerComponent destroyerComponent;
             MockComponent mockComponent;
             mockComponent.myInt = 2;
+            mockComponent.myString = "blah";
 
             worldBuilder.SetComponent(entity, destroyerComponent);
             worldBuilder.SetComponent(entity, mockComponent);
@@ -719,7 +700,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var message in ReadMessages<DestroyComponentMessage>())
+                foreach (var message in ReadMessages<DestroyComponentMessage>())
                 {
                     Destroy(message.entity);
                 }
@@ -729,8 +710,6 @@ namespace Tests
         [Test]
         public void DestroyEntityWithoutID()
         {
-            results.Clear();
-
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new AddComponentEngine());
             worldBuilder.AddEngine(new DestroyEntityEngine());
@@ -754,7 +733,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<DestroyerComponent>())
+                foreach (var (componentPair, entity) in ReadComponentsIncludingEntity<DestroyerComponent>())
                 {
                     RemoveComponent<MockComponent>(entity);
                     Destroy(entity);
@@ -786,7 +765,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                foreach (var (mockComponent, entity) in ReadComponentsIncludingEntity<MockComponent>())
                 {
                     RemoveComponent<MockComponent>(entity);
                     SetComponent(entity, new MockComponent());
@@ -801,7 +780,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                ref readonly var entity = ref ReadEntity<MockComponent>();
+                var (_, entity) = ReadComponentIncludingEntity<MockComponent>();
             }
         }
 
@@ -826,7 +805,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                foreach (var (component, entity) in ReadComponentsIncludingEntity<MockComponent>())
                 {
                     RemoveComponent<MockComponent>(entity);
                     SendMessage(new MockMessage { }, 1);
@@ -837,12 +816,12 @@ namespace Tests
         [Test]
         public void EngineSendMessageDelayed()
         {
-            Array.Clear(resultMessages, 0, resultMessages.Length);
+            resultMessages.Clear();
 
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new ActivateTimeDilationEngine());
             worldBuilder.AddEngine(new DelayedMessageEngine());
-            worldBuilder.AddEngine(new ReadMessagesEngine());
+            worldBuilder.AddEngine(new MessageReadEngine());
 
             var entity = worldBuilder.CreateEntity();
             worldBuilder.SetComponent(entity, new MockComponent { });
@@ -873,7 +852,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                foreach (var (component, entity) in ReadComponentsIncludingEntity<MockComponent>())
                 {
                     RemoveComponent<MockComponent>(entity);
                     SendMessageIgnoringTimeDilation(new MockMessage { }, 1);
@@ -884,12 +863,12 @@ namespace Tests
         [Test]
         public void EngineSendMessageDelayedIgnoringTimeDilation()
         {
-            Array.Clear(resultMessages, 0, resultMessages.Length);
+            resultMessages.Clear();
 
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new ActivateTimeDilationEngine());
             worldBuilder.AddEngine(new DelayedMessageIgnoringTimeDilationEngine());
-            worldBuilder.AddEngine(new ReadMessagesEngine());
+            worldBuilder.AddEngine(new MessageReadEngine());
 
             var entity = worldBuilder.CreateEntity();
             worldBuilder.SetComponent(entity, new MockComponent { });
@@ -917,7 +896,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var message in ReadMessages<MockMessage>())
+                foreach (var message in ReadMessages<MockMessage>())
                 {
                     var entity = CreateEntity();
                     SetComponent(entity, new MockComponent { });
@@ -955,7 +934,7 @@ namespace Tests
             resultComponents.Should().BeEmpty();
         }
 
-        struct DestroyComponentMessage { public Entity entity; }
+        struct DestroyComponentMessage : IMessage { public Entity entity; }
 
         [Reads(typeof(MockComponent))]
         [Writes(typeof(MockComponent))]
@@ -982,7 +961,7 @@ namespace Tests
         }
 
         [Test]
-        public void ReadEntity()
+        public void GetEntityByComponentType()
         {
             var worldBuilder = new WorldBuilder();
             worldBuilder.AddEngine(new ReadEntityByComponentTypeEngine());
@@ -996,25 +975,14 @@ namespace Tests
             entity.Should().BeEquivalentTo(readEntity);
         }
 
-        [Test]
+        struct MockComponentB : IComponent
-        public void ReadEntityThrowsWhenNoComponentOfTypeExists()
         {
-            var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine(new ReadEntityByComponentTypeEngine());
-
-            var world = worldBuilder.Build();
-
-            Assert.Throws<NoComponentOfTypeException>(() => world.Update(0.01), "No component of type MockComponent exists");
-        }
-
-        struct MockComponentB
-        {
-            private int value;
-
             public MockComponentB(int value)
             {
                 this.value = value;
             }
+
+            int value;
         }
 
         static MockComponentB getComponentResult;
@@ -1166,7 +1134,7 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                foreach (var (_, entity) in ReadComponentsIncludingEntity<MockComponent>())
                 {
                     RemoveComponent<MockComponent>(entity);
                 }
@@ -1324,7 +1292,6 @@ namespace Tests
             undilatedDeltaTime.Should().Be(0.5);
         }
 
-        [Adds(typeof(MockComponent))]
         class AddComponentWithoutPriorityEngine : Engine
         {
             public override void Update(double dt)
@@ -1362,7 +1329,8 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                ref readonly var entity = ref ReadEntity<MockComponent>();
+                var (component, entity) = ReadComponentIncludingEntity<MockComponent>();
+
                 AddComponent(entity, new MockComponent());
             }
         }
@@ -1381,7 +1349,6 @@ namespace Tests
             Assert.Throws<IllegalWriteException>(() => world.Update(0.01));
         }
 
-        [Adds(typeof(MockComponentB))]
         [WritesImmediate(typeof(MockComponentB))]
         class AddImmediateComponentEngine : Engine
         {
@@ -1397,7 +1364,8 @@ namespace Tests
         {
             public override void Update(double dt)
             {
-                ref readonly var component = ref ReadComponent<MockComponentB>();
+                var (component, entity) = ReadComponentIncludingEntity<MockComponentB>();
+
                 getComponentResult = component;
             }
         }
@@ -1452,10 +1420,11 @@ namespace Tests
 
         public class QueryTests
         {
-            struct MockComponentB { }
+            struct MockComponentB : IComponent { }
-            struct MockComponentC { }
+            struct MockComponentC : IComponent { }
-            struct MockComponentD { }
+            struct MockComponentD : IComponent { }
 
+            [Reads(typeof(MockComponent), typeof(MockComponentB))]
             [Writes(typeof(MockComponentB))]
             [QueryWith(typeof(MockComponent), typeof(MockComponentB))]
             class EntityQueryWithComponentsEngine : Engine
@@ -1509,6 +1478,7 @@ namespace Tests
                 queriedEntities.Should().BeEmpty();
             }
 
+            [Reads(typeof(MockComponent))]
             [Writes(typeof(MockComponent))]
             [QueryWithout(typeof(MockComponent))]
             class EntityQueryWithoutComponentsEngine : Engine
@@ -1562,6 +1532,7 @@ namespace Tests
                 queriedEntities.Should().BeEmpty();
             }
 
+            [Reads(typeof(MockComponent), typeof(MockComponentB), typeof(MockComponentD))]
             [QueryWith(typeof(MockComponent), typeof(MockComponentB))]
             [QueryWithout(typeof(MockComponentD))]
             class EntityQueryWithandWithoutComponentsEngine : Engine
@@ -1787,6 +1758,7 @@ namespace Tests
             }
 
             [ReadsImmediate(typeof(MockComponentB))]
+            [Reads(typeof(MockComponent))]
             [QueryWith(typeof(MockComponent), typeof(MockComponentB))]
             class EntityQueryWithImmediateAndNonImmediateComponents : Engine
             {
@@ -1839,7 +1811,7 @@ namespace Tests
                 }
                 public override void Update(double dt)
                 {
-                    _components.AddRange(ReadComponents<MockComponentB>().ToArray());
+                    _components.AddRange(ReadComponents<MockComponentB>());
                 }
             }
 
@@ -1875,11 +1847,12 @@ namespace Tests
 
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var entity in ReadEntities<MockComponent>())
+                    foreach (var (component, entity) in ReadComponentsIncludingEntity<MockComponent>())
                     {
                         if (HasComponent<MockComponentB>(entity))
                         {
                             _components.Add(GetComponent<MockComponentB>(entity));
+
                         }
                     }
                 }
@@ -1904,14 +1877,14 @@ namespace Tests
                 _components.Should().NotBeEmpty();
             }
 
-            struct MockTimerComponent
+            struct MockTimerComponent : IComponent
             {
-                public double Timer { get; }
-
                 public MockTimerComponent(double time)
                 {
                     Timer = time;
                 }
+
+                public double Timer { get; set; }
             }
 
             [Reads(typeof(MockTimerComponent))]
@@ -1920,18 +1893,19 @@ namespace Tests
             {
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var entity in ReadEntities<MockTimerComponent>())
+                    foreach (var (component, entity) in ReadComponentsIncludingEntity<MockTimerComponent>())
                     {
-                        ref readonly var component = ref GetComponent<MockTimerComponent>(entity);
+                        var updatedComponent = component;
+                        updatedComponent.Timer -= dt;
 
-                        if (component.Timer - dt <= 0)
+                        if (updatedComponent.Timer <= 0)
                         {
                             RemoveComponent<MockTimerComponent>(entity);
 
                         }
                         else
                         {
-                            SetComponent<MockTimerComponent>(entity, new MockTimerComponent(component.Timer - dt));
+                            SetComponent<MockTimerComponent>(entity, updatedComponent);
                         }
                     }
                 }

test/GeneralRendererTest.cs

@@ -5,18 +5,17 @@ namespace Tests
 {
     public static class GeneralRendererTest
     {
-        struct AComponent { }
+        struct AComponent : IComponent { }
 
         public class SingletonRead
         {
             static (AComponent, Entity) result;
 
-            class TestRenderer : Renderer
+            class TestRenderer : GeneralRenderer
             {
-                public override void Render(double dt, double alpha)
+                public override void Render()
                 {
-                    ref readonly var entity = ref ReadEntity<AComponent>();
+                    result = ReadComponentIncludingEntity<AComponent>();
-                    result = (GetComponent<AComponent>(entity), entity);
                 }
             }
 
@@ -24,7 +23,7 @@ namespace Tests
             public void SingletonComponent()
             {
                 var worldBuilder = new WorldBuilder();
-                worldBuilder.AddRenderer(new TestRenderer());
+                worldBuilder.AddGeneralRenderer(new TestRenderer(), 1);
 
                 AComponent aComponent;
 
@@ -34,10 +33,10 @@ namespace Tests
                 var world = worldBuilder.Build();
 
                 world.Update(0.01f);
-                world.Draw(0.01f, 0);
+                world.Draw();
 
                 world.Update(0.01);
-                world.Draw(0.01f, 0);
+                world.Draw();
 
                 Assert.That(result, Is.EqualTo((aComponent, entity)));
             }
@@ -46,7 +45,7 @@ namespace Tests
             public void MultipleComponents()
             {
                 var worldBuilder = new WorldBuilder();
-                worldBuilder.AddRenderer(new TestRenderer());
+                worldBuilder.AddGeneralRenderer(new TestRenderer(), 1);
 
                 AComponent aComponent;
                 AComponent aComponentTwo;
@@ -59,10 +58,10 @@ namespace Tests
                 var world = worldBuilder.Build();
 
                 world.Update(0.01f);
-                world.Draw(0.01f, 0);
+                world.Draw();
 
                 world.Update(0.01f);
-                world.Draw(0.01f, 0);
+                world.Draw();
 
                 Assert.That(result, Is.EqualTo((aComponent, entity)).Or.EqualTo((aComponentTwo, entityB)));
             }

test/OrderedRendererTest.cs

@@ -0,0 +1,109 @@
+using System;
+
+using NUnit.Framework;
+using FluentAssertions;
+using Encompass;
+using System.Collections.Generic;
+
+namespace Tests
+{
+    public class OrderedRendererTest
+    {
+        struct AComponent : IComponent { }
+        struct BComponent : IComponent { }
+        struct CComponent : IComponent { }
+
+        struct TestDrawComponent : IComponent, IDrawableComponent
+        {
+            public int Layer { get; set; }
+        }
+
+        class TestRenderer : OrderedRenderer<TestDrawComponent>
+        {
+            public override void Render(Entity entity, TestDrawComponent testDrawComponent) { }
+        }
+
+        static bool called = false;
+        class DeactivatedRenderer : TestRenderer
+        {
+            public override void Render(Entity entity, TestDrawComponent testDrawComponent)
+            {
+                called = true;
+            }
+        }
+
+        static bool calledOnDraw = false;
+        static (TestDrawComponent, Entity) resultComponent;
+
+        class CalledRenderer : OrderedRenderer<TestDrawComponent>
+        {
+            public override void Render(Entity entity, TestDrawComponent testDrawComponent)
+            {
+                resultComponent = (testDrawComponent, entity);
+                calledOnDraw = true;
+            }
+        }
+
+        [Test]
+        public void RenderMethodCalledOnWorldDraw()
+        {
+            var worldBuilder = new WorldBuilder();
+            worldBuilder.RegisterDrawLayer(2);
+
+            var renderer = worldBuilder.AddOrderedRenderer(new CalledRenderer());
+
+            AComponent aComponent;
+            CComponent cComponent;
+
+            var testDrawComponent = new TestDrawComponent { Layer = 2 };
+
+            var entity = worldBuilder.CreateEntity();
+            worldBuilder.SetComponent(entity, aComponent);
+            worldBuilder.SetComponent(entity, cComponent);
+            worldBuilder.SetComponent(entity, testDrawComponent);
+
+            var world = worldBuilder.Build();
+
+            world.Update(0.01f);
+            world.Draw();
+
+            Assert.IsTrue(calledOnDraw);
+            resultComponent.Should().BeEquivalentTo((testDrawComponent, entity));
+        }
+
+        [Reads(typeof(TestDrawComponent))]
+        class DestroyerEngine : Engine
+        {
+            public override void Update(double dt)
+            {
+                foreach (var entity in ReadEntities<TestDrawComponent>())
+                {
+                    Destroy(entity);
+                }
+            }
+        }
+        [Test]
+        public void RenderMethodNotCalledAfterDestroy()
+        {
+            calledOnDraw = false;
+
+            var worldBuilder = new WorldBuilder();
+            worldBuilder.RegisterDrawLayer(1);
+
+            worldBuilder.AddEngine(new DestroyerEngine());
+            var renderer = worldBuilder.AddOrderedRenderer(new CalledRenderer());
+
+            TestDrawComponent testDrawComponent = new TestDrawComponent { Layer = 1 };
+
+            var entity = worldBuilder.CreateEntity();
+            worldBuilder.SetComponent(entity, testDrawComponent);
+
+            var world = worldBuilder.Build();
+
+            world.Update(0.01);
+            world.Draw();
+
+            Assert.IsFalse(calledOnDraw);
+        }
+    }
+}

test/SpawnerTest.cs

@@ -5,8 +5,8 @@ namespace Tests
 {
     public class SpawnerTest
     {
-        struct TestComponent { }
+        struct TestComponent : IComponent { }
-        struct SpawnMessageA { }
+        struct SpawnMessageA : IMessage { }
 
         static Entity resultEntity;
 
@@ -23,7 +23,7 @@ namespace Tests
         [Writes(typeof(TestComponent))]
         class TestSpawner : Spawner<SpawnMessageA>
         {
-            protected override void Spawn(in SpawnMessageA message)
+            protected override void Spawn(SpawnMessageA message)
             {
                 resultEntity = CreateEntity();
                 SetComponent(resultEntity, new TestComponent());

test/WorldBuilderTest.cs

@@ -5,7 +5,6 @@ using System.Collections.Generic;
 using Encompass.Exceptions;
 using System.Linq;
 using FluentAssertions;
-using System;
 
 namespace Tests
 {
@@ -13,8 +12,8 @@ namespace Tests
     {
         public class EngineCycleSimple
         {
-            struct AMessage { }
+            struct AMessage : IMessage { }
-            struct BMessage { }
+            struct BMessage : IMessage { }
 
             [Receives(typeof(AMessage))]
             [Sends(typeof(BMessage))]
@@ -51,10 +50,10 @@ namespace Tests
 
         public class EngineCycleComplex
         {
-            struct AMessage { }
+            struct AMessage : IMessage { }
-            struct BMessage { }
+            struct BMessage : IMessage { }
-            struct CMessage { }
+            struct CMessage : IMessage { }
-            struct DMessage { }
+            struct DMessage : IMessage { }
 
             [Receives(typeof(AMessage))]
             [Sends(typeof(BMessage))]
@@ -115,7 +114,7 @@ namespace Tests
 
         public class MultipleEngineWriteConflict
         {
-            struct AComponent { }
+            struct AComponent : IComponent { }
 
             [Writes(typeof(AComponent))]
             class AEngine : Engine
@@ -142,12 +141,12 @@ namespace Tests
 
         public class MultipleEngineWriteWithPriority
         {
-            struct SetMessage
+            struct SetMessage : IMessage
             {
                 public Entity entity;
             }
 
-            struct AComponent
+            struct AComponent : IComponent
             {
                 public int myInt;
             }
@@ -159,7 +158,7 @@ namespace Tests
             {
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var setMessage in ReadMessages<SetMessage>())
+                    foreach (var setMessage in ReadMessages<SetMessage>())
                     {
                         SetComponent(setMessage.entity, new AComponent { myInt = 0 });
                     }
@@ -173,7 +172,7 @@ namespace Tests
             {
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var setMessage in ReadMessages<SetMessage>())
+                    foreach (var setMessage in ReadMessages<SetMessage>())
                     {
                         SetComponent(setMessage.entity, new AComponent { myInt = 1 });
                     }
@@ -211,12 +210,12 @@ namespace Tests
 
         public class DefaultWritePriority
         {
-            struct SetMessage
+            struct SetMessage : IMessage
             {
                 public Entity entity;
             }
 
-            struct AComponent
+            struct AComponent : IComponent
             {
                 public int myInt;
             }
@@ -229,7 +228,7 @@ namespace Tests
             {
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var setMessage in ReadMessages<SetMessage>())
+                    foreach (var setMessage in ReadMessages<SetMessage>())
                     {
                         SetComponent(setMessage.entity, new AComponent { myInt = 5 });
                     }
@@ -244,7 +243,7 @@ namespace Tests
             {
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var setMessage in ReadMessages<SetMessage>())
+                    foreach (var setMessage in ReadMessages<SetMessage>())
                     {
                         SetComponent(setMessage.entity, new AComponent { myInt = 1 });
                     }
@@ -258,7 +257,7 @@ namespace Tests
             {
                 public override void Update(double dt)
                 {
-                    foreach (ref readonly var setMessage in ReadMessages<SetMessage>())
+                    foreach (var setMessage in ReadMessages<SetMessage>())
                     {
                         SetComponent(setMessage.entity, new AComponent { myInt = 3 });
                     }
@@ -298,7 +297,7 @@ namespace Tests
 
         public class EngineMessageSelfCycle
         {
-            struct AMessage { }
+            struct AMessage : IMessage { }
 
             [Receives(typeof(AMessage))]
             [Sends(typeof(AMessage))]
@@ -319,6 +318,50 @@ namespace Tests
             }
         }
 
+        public class IllegalReadType
+        {
+            struct ANonMessage { }
+
+            [Reads(typeof(ANonMessage))]
+            class MyEngine : Engine
+            {
+                public override void Update(double dt)
+                {
+
+                }
+            }
+
+            [Test]
+            public void ThrowsError()
+            {
+                var worldBuilder = new WorldBuilder();
+
+                Assert.Throws<IllegalReadTypeException>(() => worldBuilder.AddEngine(new MyEngine()), "ANonMessage must be a Message or Component");
+            }
+        }
+
+        public class IllegalWriteType
+        {
+            struct ANonMessage { }
+
+            [Sends(typeof(ANonMessage))]
+            class MyEngine : Engine
+            {
+                public override void Update(double dt)
+                {
+
+                }
+            }
+
+            [Test]
+            public void ThrowsError()
+            {
+                var worldBuilder = new WorldBuilder();
+
+                Assert.Throws<IllegalSendTypeException>(() => worldBuilder.AddEngine(new MyEngine()), "ANonMessage must be a Message or Component");
+            }
+        }
+
         public class PriorityConflict
         {
             [Writes(typeof(MockComponent), 2)]
@@ -385,13 +428,13 @@ namespace Tests
         {
             static List<Engine> order = new List<Engine>();
 
-            struct AComponent { }
+            struct AComponent : IComponent { }
-            struct BComponent { }
+            struct BComponent : IComponent { }
 
-            struct AMessage { }
+            struct AMessage : IMessage { }
-            struct BMessage { }
+            struct BMessage : IMessage { }
-            struct CMessage { }
+            struct CMessage : IMessage { }
-            struct DMessage { }
+            struct DMessage : IMessage { }
 
             [Sends(typeof(AMessage))]
             class AEngine : Engine
@@ -458,22 +501,20 @@ namespace Tests
                 Assert.That(order.IndexOf(engineC), Is.LessThan(order.IndexOf(engineD)));
             }
 
-            static AMessage[] resultMessages;
+            static List<AMessage> resultMessages = new List<AMessage>();
 
             [Receives(typeof(AMessage))]
             class ReadMessageEngine : Engine
             {
                 public override void Update(double dt)
                 {
-                    resultMessages = ReadMessages<AMessage>().ToArray();
+                    resultMessages = ReadMessages<AMessage>().ToList();
                 }
             }
 
             [Test]
             public void SendMessageDelayed()
             {
-                resultMessages = Array.Empty<AMessage>();
-
                 var worldBuilder = new WorldBuilder();
                 worldBuilder.AddEngine(new ReadMessageEngine());
 
@@ -498,8 +539,8 @@ namespace Tests
         {
             static List<Engine> order = new List<Engine>();
 
-            struct AMessage { }
+            struct AMessage : IMessage { }
-            struct BMessage { }
+            struct BMessage : IMessage { }
 
             [Sends(typeof(AMessage), typeof(BMessage))]
             class AEngine : Engine

test/WorldTest.cs

@@ -0,0 +1,81 @@
+using NUnit.Framework;
+using FluentAssertions;
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+using Encompass;
+
+namespace Tests
+{
+    public class WorldTest
+    {
+        struct TestComponent : IComponent { }
+        struct TestDrawComponent : IComponent, IDrawableComponent
+        {
+            public int Layer { get; set; }
+        }
+
+        static List<object> drawOrder = new List<object>();
+
+        class TestEntityRenderer : OrderedRenderer<TestDrawComponent>
+        {
+            public override void Render(Entity entity, TestDrawComponent testDrawComponent)
+            {
+                drawOrder.Add(entity);
+            }
+        }
+
+        class TestGeneralRenderer : GeneralRenderer
+        {
+            public override void Render()
+            {
+                drawOrder.Add(this);
+            }
+        }
+
+        [Test]
+        public void DrawOrder()
+        {
+            var worldBuilder = new WorldBuilder();
+            worldBuilder.RegisterDrawLayer(1);
+            worldBuilder.RegisterDrawLayer(2);
+            worldBuilder.RegisterDrawLayer(3);
+            worldBuilder.RegisterDrawLayer(4);
+            worldBuilder.RegisterDrawLayer(7);
+
+            worldBuilder.AddOrderedRenderer(new TestEntityRenderer());
+            var testGeneralRenderer = worldBuilder.AddGeneralRenderer(new TestGeneralRenderer(), 7);
+
+            TestComponent testComponent;
+            TestDrawComponent drawComponentThree = new TestDrawComponent { Layer = 3 };
+            var drawComponentTwo = new TestDrawComponent { Layer = 2 };
+            var drawComponentOne = new TestDrawComponent { Layer = 1 };
+            var drawComponentFour = new TestDrawComponent { Layer = 4 };
+
+            var entity = worldBuilder.CreateEntity();
+            worldBuilder.SetComponent(entity, testComponent);
+            worldBuilder.SetComponent(entity, drawComponentThree);
+
+            var entityTwo = worldBuilder.CreateEntity();
+            worldBuilder.SetComponent(entityTwo, testComponent);
+            worldBuilder.SetComponent(entityTwo, drawComponentTwo);
+
+            var entityThree = worldBuilder.CreateEntity();
+            worldBuilder.SetComponent(entityThree, testComponent);
+            worldBuilder.SetComponent(entityThree, drawComponentThree);
+
+            var entityFour = worldBuilder.CreateEntity();
+            worldBuilder.SetComponent(entityFour, testComponent);
+            worldBuilder.SetComponent(entityFour, drawComponentFour);
+
+            var world = worldBuilder.Build();
+
+            world.Update(0.01f);
+            world.Draw();
+
+            drawOrder.Should().BeEquivalentTo(entityFour, entityTwo, entity, entityThree, testGeneralRenderer);
+        }
+    }
+}

test/test.csproj

@@ -1,12 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>netcoreapp3.0</TargetFramework>
     <IsPackable>false</IsPackable>
     <RootNamespace>Tests</RootNamespace>
     <AssemblyName>EncompassECS.Framework.Tests</AssemblyName>
-    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <Platforms>x64;x86</Platforms>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="FluentAssertions" Version="5.7.0" />