Fix stale data for main light directional cookie.

com.unity.render-pipelines.universal/Runtime/LightCookieManager.cs

@@ -31,6 +31,8 @@ static class ShaderProperty
 
         private enum LightCookieShaderFormat
         {
+            None = -1,
+
             RGB = 0,
             Alpha = 1,
             Red = 2
@@ -580,6 +582,13 @@ bool SetupMainLight(CommandBuffer cmd, ref VisibleLight visibleMainLight)
                 cmd.SetGlobalMatrix(ShaderProperty.mainLightWorldToLight, cookieMatrix);
                 cmd.SetGlobalFloat(ShaderProperty.mainLightCookieTextureFormat, cookieFormat);
             }
+            else
+            {
+                // Make sure we erase stale data in case the main light is disabled but cookie system is enabled (for additional lights).
+                cmd.SetGlobalTexture(ShaderProperty.mainLightTexture, Texture2D.whiteTexture);
+                cmd.SetGlobalMatrix(ShaderProperty.mainLightWorldToLight, Matrix4x4.identity);
+                cmd.SetGlobalFloat(ShaderProperty.mainLightCookieTextureFormat, (float)LightCookieShaderFormat.None);
+            }
 
             return isMainLightCookieEnabled;
         }

com.unity.render-pipelines.universal/ShaderLibrary/LightCookie/LightCookie.hlsl

@@ -17,7 +17,7 @@ float2 ComputeLightCookieUVDirectional(float4x4 worldToLight, float3 samplePosit
 {
     // Translate and rotate 'positionWS' into the light space.
     // Project point to light "view" plane, i.e. discard Z.
-    float2 positionLS   = mul(worldToLight, float4(samplePositionWS, 1)).xy;
+    float2 positionLS = mul(worldToLight, float4(samplePositionWS, 1)).xy;
 
     // Remap [-1, 1] to [0, 1]
     // (implies the transform has ortho projection mapping world space box to [-1, 1])
@@ -70,6 +70,9 @@ float2 ComputeLightCookieUVPoint(float4x4 worldToLight, float3 samplePositionWS,
 
 real3 SampleMainLightCookie(float3 samplePositionWS)
 {
+    if(!IsMainLightCookieEnabled())
+        return real3(1,1,1);
+
     float2 uv = ComputeLightCookieUVDirectional(_MainLightWorldToLight, samplePositionWS, float4(1, 1, 0, 0), URP_TEXTURE_WRAP_MODE_NONE);
     real4 color = SampleMainLightCookieTexture(uv);
 

com.unity.render-pipelines.universal/ShaderLibrary/LightCookie/LightCookieInput.hlsl

@@ -103,6 +103,10 @@ real4 SampleAdditionalLightsCookieAtlasTexture(float2 uv)
 }
 
 // Helpers
+bool IsMainLightCookieEnabled()
+{
+    return _MainLightCookieTextureFormat != URP_LIGHT_COOKIE_FORMAT_NONE;
+}
 
 bool IsLightCookieEnabled(int lightBufferIndex)
 {

com.unity.render-pipelines.universal/ShaderLibrary/LightCookie/LightCookieTypes.hlsl

@@ -5,6 +5,7 @@
 
 // Types
 
+#define URP_LIGHT_COOKIE_FORMAT_NONE (-1)
 #define URP_LIGHT_COOKIE_FORMAT_RGB (0)
 #define URP_LIGHT_COOKIE_FORMAT_ALPHA (1)
 #define URP_LIGHT_COOKIE_FORMAT_RED (2)