From a914c586b2b01dc2d103551365a9025326e77e3e Mon Sep 17 00:00:00 2001
From: cosmonaut <evan@moonside.games>
Date: Fri, 2 Oct 2020 17:29:20 -0700
Subject: [PATCH] experiment with color banding

---
 Effects/Deferred_ToonEffect.cs      |  8 -------
 Effects/FXB/Deferred_ToonEffect.fxb |  4 ++--
 Effects/HLSL/Deferred_ToonEffect.fx | 33 ++++++++++++++++++-----------
 Renderer.cs                         |  2 --
 4 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/Effects/Deferred_ToonEffect.cs b/Effects/Deferred_ToonEffect.cs
index a55b678..f5d2bfe 100644
--- a/Effects/Deferred_ToonEffect.cs
+++ b/Effects/Deferred_ToonEffect.cs
@@ -18,8 +18,6 @@ namespace Kav
         EffectParameter directionalLightDirectionParam;
         EffectParameter directionalLightColorParam;
 
-        EffectParameter softnessParam;
-
         EffectParameter cascadeFarPlanesParam;
         EffectParameter shadowMapSizeParam;
 
@@ -43,8 +41,6 @@ namespace Kav
         public Vector3 DirectionalLightDirection { get; set; }
         public Vector3 DirectionalLightColor { get; set; }
 
-        public float Softness { get; set; }
-
         public float[] CascadeFarPlanes { get; }
         public float ShadowMapSize { get; set; }
 
@@ -76,8 +72,6 @@ namespace Kav
             directionalLightDirectionParam.SetValue(DirectionalLightDirection);
             directionalLightColorParam.SetValue(DirectionalLightColor);
 
-            softnessParam.SetValue(Softness);
-
             cascadeFarPlanesParam.SetValue(CascadeFarPlanes);
             shadowMapSizeParam.SetValue(ShadowMapSize);
 
@@ -104,8 +98,6 @@ namespace Kav
             directionalLightDirectionParam = Parameters["DirectionalLightDirection"];
             directionalLightColorParam     = Parameters["DirectionalLightColor"];
 
-            softnessParam                  = Parameters["Softness"];
-
             cascadeFarPlanesParam          = Parameters["CascadeFarPlanes"];
             shadowMapSizeParam             = Parameters["ShadowMapSize"];
 
diff --git a/Effects/FXB/Deferred_ToonEffect.fxb b/Effects/FXB/Deferred_ToonEffect.fxb
index f40c541..bcd420f 100644
--- a/Effects/FXB/Deferred_ToonEffect.fxb
+++ b/Effects/FXB/Deferred_ToonEffect.fxb
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:6f1008f0dd9ab943b47e548d9f61d122e44785f7fbb9ea47b7d73448af681016
-size 21180
+oid sha256:725d85ea8bb4ad3016dadae76f6da73792b3f46f99facdd5fe91a5666cc3a13a
+size 21072
diff --git a/Effects/HLSL/Deferred_ToonEffect.fx b/Effects/HLSL/Deferred_ToonEffect.fx
index 9da8035..6806710 100644
--- a/Effects/HLSL/Deferred_ToonEffect.fx
+++ b/Effects/HLSL/Deferred_ToonEffect.fx
@@ -18,8 +18,6 @@ float3 EyePosition                           _ps(c0)     _cb(c0);
 float3 DirectionalLightDirection             _ps(c1)     _cb(c1);
 float3 DirectionalLightColor                 _ps(c2)     _cb(c2);
 
-float Softness                               _ps(c3)     _cb(c3);
-
 float CascadeFarPlanes[NUM_SHADOW_CASCADES]  _ps(c4)     _cb(c4);
 
 float ShadowMapSize                          _ps(c8)     _cb(c8);
@@ -138,6 +136,26 @@ float ComputeShadow(float3 positionWorldSpace, float3 N, float3 L)
     }
 }
 
+float IntensityBanding(float NdotL)
+{
+    if (NdotL > 0.5)
+    {
+        return 1.0;
+    }
+    else if (NdotL > 0.25)
+    {
+        return 0.5;
+    }
+    else if (NdotL > 0.0)
+    {
+        return 0.25;
+    }
+    else
+    {
+        return 0.0;
+    }
+}
+
 // FIXME: organize this
 float4 main_ps(PixelInput input) : SV_TARGET0
 {
@@ -153,16 +171,7 @@ float4 main_ps(PixelInput input) : SV_TARGET0
     float NdotL = dot(N, L);
     float NdotH = max(dot(N, H), 0.0);
 
-    float lightIntensity;
-    if (Softness > 0.0)
-    {
-        lightIntensity = smoothstep(0, Softness, NdotL);
-    }
-    else
-    {
-        lightIntensity = (NdotL > 0.0) ? 1.0 : 0.0;
-    }
-
+    float lightIntensity = IntensityBanding(NdotL);
     float3 light = lightIntensity * DirectionalLightColor;
 
     float specularIntensity = pow(NdotH * lightIntensity, 32 * 32);
diff --git a/Renderer.cs b/Renderer.cs
index a67e3b8..e8b2bf8 100644
--- a/Renderer.cs
+++ b/Renderer.cs
@@ -352,8 +352,6 @@ namespace Kav
             Deferred_ToonEffect.DirectionalLightColor = 
                 directionalLight.Color.ToVector3() * directionalLight.Intensity;
 
-            Deferred_ToonEffect.Softness = 0.01f;
-
             Deferred_ToonEffect.ShadowMapOne = ShadowRenderTargets[0];
             if (NumShadowCascades > 1)
             {