fix sh not working properly in some cases

Author: z3y

Editor/Importer/Importer.cs

@@ -9,7 +9,7 @@
 
 namespace Graphlit
 {
-    [ScriptedImporter(6, new[] { "graphlit", "subgraphlit", "zsg" }, 0)]
+    [ScriptedImporter(7, new[] { "graphlit", "subgraphlit", "zsg" }, 0)]
     public class ShaderGraphImporter : ScriptedImporter
     {
         internal static Dictionary<string, ShaderGraphView> _graphViews = new();

Editor/ShaderNode/Nodes/Functions/Toon Light.hlsl

@@ -2,9 +2,10 @@
 
 #include "Main Light.hlsl"
 
+#define OPENLIT_FALLBACK_DIRECTION  float4(0.001,0.002,0.001,0)
 void ShadeSH9ToonDouble(float3 lightDirection, out float3 shMax, out float3 shMin)
 {
-    #if !defined(LIGHTMAP_ON)
+    #if !defined(LIGHTMAP_ON) && UNITY_SHOULD_SAMPLE_SH
         float3 N = lightDirection * 0.666666;
         float4 vB = N.xyzz * N.yzzx;
         // L0 L2
@@ -43,27 +44,27 @@ float OpenLitGray(float3 rgb)
     return dot(rgb, float3(1.0/3.0, 1.0/3.0, 1.0/3.0));
 }
 
+float3 ComputeCustomLightDirection(float4 lightDirectionOverride)
+{
+    float3 customDir = length(lightDirectionOverride.xyz) * normalize(mul((float3x3)UNITY_MATRIX_M, lightDirectionOverride.xyz));
+    return lightDirectionOverride.w ? customDir : lightDirectionOverride.xyz;
+}
 
 void ComputeLightDirection(float3 mainLightDir, float3 mainLightCol, out float3 lightDirection, out float3 lightDirectionForSH9)
 {
     float3 mainDir = mainLightDir * OpenLitLuminance(mainLightCol);
-    #if !defined(LIGHTMAP_ON)
+    #if !defined(LIGHTMAP_ON) && UNITY_SHOULD_SAMPLE_SH
         float3 sh9Dir = unity_SHAr.xyz * 0.333333 + unity_SHAg.xyz * 0.333333 + unity_SHAb.xyz * 0.333333;
         float3 sh9DirAbs = float3(sh9Dir.x, abs(sh9Dir.y), sh9Dir.z);
-		UNITY_FLATTEN
-        if (!any(unity_SHC.xyz))
-        {
-            sh9Dir = 0;
-            sh9DirAbs = 0;
-        }
     #else
         float3 sh9Dir = 0;
         float3 sh9DirAbs = 0;
     #endif
+    float3 customDir = ComputeCustomLightDirection(OPENLIT_FALLBACK_DIRECTION);
 
-    lightDirection = normalize(sh9DirAbs + mainDir);
-    // lightDirectionForSH9 = sh9Dir + mainDir;
-    lightDirectionForSH9 = sh9Dir;
+    lightDirection = normalize(sh9DirAbs + mainDir + customDir);
+    lightDirectionForSH9 = sh9Dir + mainDir;
+    // lightDirectionForSH9 = sh9Dir;
     lightDirectionForSH9 = dot(lightDirectionForSH9, lightDirectionForSH9) < 0.000001 ? 0 : normalize(lightDirectionForSH9);
 }
 

Editor/Targets/Lit/LitTemplate.cs

@@ -201,7 +201,7 @@ public override void OnBeforeBuild(ShaderBuilder builder)
                 pass.pragmas.Add("#pragma shader_feature_local _ _ALPHAFADE_ON _ALPHATEST_ON _ALPHAPREMULTIPLY_ON _ALPHAMODULATE_ON");
 
                 pass.pragmas.Add("#pragma multi_compile_fwdbase");
-                pass.pragmas.Add("#pragma skip_variants LIGHTPROBE_SH");
+                //pass.pragmas.Add("#pragma skip_variants LIGHTPROBE_SH");
                 pass.pragmas.Add("#pragma multi_compile_fog");
                 pass.pragmas.Add("#pragma multi_compile_instancing");
                 pass.pragmas.Add("#pragma shader_feature_fragment VERTEXLIGHT_ON");

Editor/Targets/Unlit/UnlitTemplate.cs

@@ -97,7 +97,7 @@ public override void OnBeforeBuild(ShaderBuilder builder)
                 if (_customLighting)
                 {
                     pass.pragmas.Add("#pragma multi_compile_fwdbase");
-                    pass.pragmas.Add("#pragma skip_variants LIGHTPROBE_SH");
+                    //pass.pragmas.Add("#pragma skip_variants LIGHTPROBE_SH");
                     pass.pragmas.Add("#pragma shader_feature_fragment VERTEXLIGHT_ON");
                 }
                 pass.pragmas.Add("#pragma multi_compile_fog");

ShaderLibrary/UnityCG/UnityCG.hlsl

@@ -22,6 +22,13 @@
 #define USING_LIGHT_MULTI_COMPILE
 #endif
 
+// Should SH (light probe / ambient) calculations be performed?
+// - When both static and dynamic lightmaps are available, no SH evaluation is performed
+// - When static and dynamic lightmaps are not available, SH evaluation is always performed
+// - For low level LODs, static lightmap and real-time GI from light probes can be combined together
+// - Passes that don't do ambient (additive, shadowcaster etc.) should not do SH either.
+#define UNITY_SHOULD_SAMPLE_SH (defined(LIGHTPROBE_SH) && !defined(UNITY_PASS_FORWARDADD) && !defined(UNITY_PASS_PREPASSBASE) && !defined(UNITY_PASS_SHADOWCASTER) && !defined(UNITY_PASS_META))
+
 #if defined(SHADER_API_D3D11) || defined(SHADER_API_PSSL) || defined(SHADER_API_METAL) || defined(SHADER_API_GLCORE) || defined(SHADER_API_GLES3) || defined(SHADER_API_VULKAN) || defined(SHADER_API_SWITCH) // D3D11, D3D12, XB1, PS4, iOS, macOS, tvOS, glcore, gles3, webgl2.0, Switch
 // Real-support for depth-format cube shadow map.
 #define SHADOWS_CUBE_IN_DEPTH_TEX