Lit Pass Integrations, Keyword config

ScriptableRenderPipeline/LightweightPipeline/LWRP/LightweightPipeline.cs

             "_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE",
             "_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT",
             "_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT",
+            "_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN",
+            "_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN",
+            "_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT",
+            "_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT",
 
             "_MAIN_LIGHT_SPOT_SHADOW",
             "_MAIN_LIGHT_SPOT_SHADOW_SOFT"
             return corners;
         }
 
+        //NOTE: Currently shader keywords are set before the forward pass, so the collect pass is one frame behind the current keyword.
-            //Reciever constants set up here in case of screen space shadows.
-            SetupShadowReceiverConstants(cmd, lights[lightData.mainLightIndex]);
-
+            SetupShadowReceiverConstants(cmd, lights[lightData.mainLightIndex]); //Reciever constants set up here in case of screen space shadows.
-            cmd.SetGlobalVectorArray("_FrustumCorners", GetFarPlaneCorners());
-            cmd.Blit(null, m_ScreenSpaceShadowMapRT, m_ScreenSpaceShadowsMaterial); 
+            cmd.SetGlobalVectorArray("_FrustumCorners", GetFarPlaneCorners()); //TODO: Move to a constant buffer. Shadow or Camera?
+            cmd.Blit(null, m_ScreenSpaceShadowMapRT, m_ScreenSpaceShadowsMaterial);
 
             context.ExecuteCommandBuffer(cmd);
             CommandBufferPool.Release(cmd);
                     m_MainLightKeywordString.Append("_DIRECTIONAL_SHADOW");
                     if (m_Asset.CascadeCount > 1)
                         m_MainLightKeywordString.Append("_CASCADE");
+
+                    if(m_Asset.UsesScreenSpaceShadows)
+                        m_MainLightKeywordString.Append("_SCREEN");
                 }
                 else
                 {
             CoreUtils.SetKeyword(cmd, "_MIXED_LIGHTING_SUBTRACTIVE", m_MixedLightingSetup == MixedLightingSetup.Subtractive);
             CoreUtils.SetKeyword(cmd, "_VERTEX_LIGHTS", vertexLightsCount > 0);
             CoreUtils.SetKeyword(cmd, "SOFTPARTICLES_ON", m_RequireDepthTexture && m_Asset.RequireSoftParticles);
-            CoreUtils.SetKeyword(cmd, "_SCREEN_SPACE_SHADOWS", m_RequireDepthTexture && m_Asset.UsesScreenSpaceShadows);
-
+           
             bool linearFogModeEnabled = false;
             bool exponentialFogModeEnabled = false;
             if (RenderSettings.fog)

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/Core.hlsl

 // Lightweight pipeline doesn't support point light shadows so they can't be //
 // classified as main light.                                                 //
 ///////////////////////////////////////////////////////////////////////////////
-#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT)
+#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT)
 #define _MAIN_LIGHT_DIRECTIONAL
 #endif
 
 {
     half3x3 tangentToWorld = half3x3(tangent, binormal, normal);
     return normalize(mul(normalTangent, tangentToWorld));
+}
+
+float4 ComputeScreenPos(float4 pos)
+{
+    float4 o = pos * 0.5f;
+    o.xy = float2(o.x, o.y * _ProjectionParams.x) + o.w;
+    o.zw = pos.zw;
+    return o;
 }
 
 half ComputeFogFactor(float z)

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/LightweightPassLit.hlsl

     half fogFactor = ComputeFogFactor(o.clipPos.z);
     o.fogFactorAndVertexLight = half4(fogFactor, vertexLight);
 
-#if defined(_SHADOWS_ENABLED) && !defined(_SHADOWS_CASCADE)
+//TODO: Macro?
+#if defined(_SHADOWS_ENABLED)
+    #if    defined(_SHADOWS_SCREEN)
+    o.shadowCoord = ComputeScreenPos(o.clipPos);
+    #elif !defined(_SHADOWS_CASCADE)
+    #endif
 #endif
 
     return o;

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/Shadows.hlsl

 // In order to reduce shader variations main light keywords were combined    //
 // here we define shadow keywords.                                           //
 ///////////////////////////////////////////////////////////////////////////////
-#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT) || defined(_MAIN_LIGHT_SPOT_SHADOW) || defined(_MAIN_LIGHT_SPOT_SHADOW_SOFT)
+#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT) || defined(_MAIN_LIGHT_SPOT_SHADOW) || defined(_MAIN_LIGHT_SPOT_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT)
-#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT) || defined(_MAIN_LIGHT_SPOT_SHADOW_SOFT)
+#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT) || defined(_MAIN_LIGHT_SPOT_SHADOW_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT)
-#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT)
+#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT)
     #define _SHADOWS_CASCADE
 #endif
 
 
+#if defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN) || defined(_MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT)
+    #define _SHADOWS_SCREEN
+#endif
+
+TEXTURE2D(_ScreenSpaceShadowMap);
+SAMPLER(sampler_ScreenSpaceShadowMap);
+
 TEXTURE2D_SHADOW(_ShadowMap);
 SAMPLER_CMP(sampler_ShadowMap);
 
 half4       _ShadowData;    // (x: shadowStrength)
 float4      _ShadowmapSize; // (xy: 1/width and 1/height, zw: width and height)
 CBUFFER_END
+
+inline half SampleScreenSpaceShadowMap(float4 shadowCoord)
+{
+    //NOTE: No macro for proj sample?
+    return SAMPLE_TEXTURE2D(_ScreenSpaceShadowMap, sampler_ScreenSpaceShadowMap, shadowCoord.xy / shadowCoord.w);
+}
 
 inline half SampleShadowmap(float4 shadowCoord)
 {
     return 1.0;
 #endif
 
-#ifdef _SHADOWS_CASCADE
-    shadowCoord = ComputeShadowCoord(positionWS);
+#ifdef _SHADOWS_SCREEN
+    return SampleScreenSpaceShadowMap(shadowCoord);
+#else
+    #ifdef _SHADOWS_CASCADE
+        shadowCoord = ComputeShadowCoord(positionWS);
+    #endif
+        return SampleShadowmap(shadowCoord);
-
-    return SampleShadowmap(shadowCoord);
 }
 
 #endif

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/LightweightScreenSpaceShadows.shader

         half Fragment(Interpolators i) : SV_Target
         {
             //Reconstruct the world position.
-            //TODO: Profile against unprojection method in core library.
-            float3 vpos = ComputeViewSpacePositionGeometric(i);
+            float3 vpos = ComputeViewSpacePositionGeometric(i); //TODO: Profile against unprojection method in core library.
             float3 wpos = mul(unity_CameraToWorld, float4(vpos, 1)).xyz;
             
             //Fetch shadow coordinates.
             // Lightweight shader library declares defines based on these keywords to avoid having to check them in the shaders
             // Core.hlsl defines _MAIN_LIGHT_DIRECTIONAL and _MAIN_LIGHT_SPOT (point lights can't be main light)
             // Shadow.hlsl defines _SHADOWS_ENABLED, _SHADOWS_SOFT, _SHADOWS_CASCADE, _SHADOWS_PERSPECTIVE
-            #pragma multi_compile _ _MAIN_LIGHT_DIRECTIONAL_SHADOW _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE _MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT _MAIN_LIGHT_SPOT_SHADOW _MAIN_LIGHT_SPOT_SHADOW_SOFT
-
+            #pragma multi_compile _ _MAIN_LIGHT_DIRECTIONAL_SHADOW _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN _MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT _MAIN_LIGHT_SPOT_SHADOW _MAIN_LIGHT_SPOT_SHADOW_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN _MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT
+            
             #pragma vertex   Vertex
             #pragma fragment Fragment
             ENDHLSL

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/LightweightStandard.shader

             // Lightweight shader library declares defines based on these keywords to avoid having to check them in the shaders
             // Core.hlsl defines _MAIN_LIGHT_DIRECTIONAL and _MAIN_LIGHT_SPOT (point lights can't be main light)
             // Shadow.hlsl defines _SHADOWS_ENABLED, _SHADOWS_SOFT, _SHADOWS_CASCADE, _SHADOWS_PERSPECTIVE
-            #pragma multi_compile _ _MAIN_LIGHT_DIRECTIONAL_SHADOW _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE _MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT _MAIN_LIGHT_SPOT_SHADOW _MAIN_LIGHT_SPOT_SHADOW_SOFT
+            #pragma multi_compile _ _MAIN_LIGHT_DIRECTIONAL_SHADOW _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN _MAIN_LIGHT_DIRECTIONAL_SHADOW_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_CASCADE_SCREEN_SOFT _MAIN_LIGHT_SPOT_SHADOW _MAIN_LIGHT_SPOT_SHADOW_SOFT _MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN _MAIN_LIGHT_DIRECTIONAL_SHADOW_SCREEN_SOFT
-            #pragma multi_compile _ _SCREEN_SPACE_SHADOWS //TODO: Move to Shadows.hlsl
 
             // -------------------------------------
             // Unity defined keywords