Considered MainLight as always a directional light. This enables the following optimation: (and potentially more)

- no position WS interpolator
     - no distance attenuation computation
     - saved homogeneous coord division as w is always 1.0 in orthogonal projections

ScriptableRenderPipeline/LightweightPipeline/LWRP/LightweightPipeline.cs

         private int GetMainLight(List<VisibleLight> visibleLights)
         {
             int totalVisibleLights = visibleLights.Count;
-            bool shadowsEnabled = m_Asset.AreShadowsEnabled();
-            int brighestDirectionalIndex = -1;
             for (int i = 0; i < totalVisibleLights; ++i)
             {
                 VisibleLight currLight = visibleLights[i];
                 if (currLight.light == null)
                     break;
 
-                // Shadow lights are sorted by type (directional > puctual) and intensity
-                // The first shadow light we find in the list is the main light
-                if (shadowsEnabled && currLight.light.shadows != LightShadows.None && LightweightUtils.IsSupportedShadowType(currLight.lightType))
+                // In case no shadow light is present we will return the brightest directional light
+                if (currLight.lightType == LightType.Directional)
-
-                // In case no shadow light is present we will return the brightest directional light
-                if (currLight.lightType == LightType.Directional && brighestDirectionalIndex == -1)
-                    brighestDirectionalIndex = i;
-            return brighestDirectionalIndex;
+            return -1;
         }
 
         private void InitializeLightConstants(List<VisibleLight> lights, int lightIndex, out Vector4 lightPos, out Vector4 lightColor, out Vector4 lightDistanceAttenuation, out Vector4 lightSpotDir,
                 }
             }
 
-            cmd.SetGlobalVector(PerCameraBuffer._MainLightPosition, lightPos);
+            cmd.SetGlobalVector(PerCameraBuffer._MainLightPosition, new Vector4(lightPos.x, lightPos.y, lightPos.z, lightDistanceAttenuation.w));
-            cmd.SetGlobalVector(PerCameraBuffer._MainLightDistanceAttenuation, lightDistanceAttenuation);
-            cmd.SetGlobalVector(PerCameraBuffer._MainLightSpotDir, lightSpotDir);
-            cmd.SetGlobalVector(PerCameraBuffer._MainLightSpotAttenuation, lightSpotAttenuation);
         }
 
         private void SetupAdditionalListConstants(CommandBuffer cmd, List<VisibleLight> lights, ref LightData lightData)

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/Input.hlsl

 CBUFFER_START(_PerCamera)
 float4 _MainLightPosition;
 half4 _MainLightColor;
-half4 _MainLightDistanceAttenuation;
-half4 _MainLightSpotDir;
-half4 _MainLightSpotAttenuation;
 float4x4 _WorldToLight;
 
 half4 _AdditionalLightCount;

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/Lighting.hlsl

 //                      Light Abstraction                                    //
 ///////////////////////////////////////////////////////////////////////////////
 
-Light GetMainLight(float3 positionWS)
+Light GetMainLight()
-    LightInput lightInput;
-    lightInput.position = _MainLightPosition;
-    lightInput.color = _MainLightColor.rgb;
-    lightInput.distanceAttenuation = _MainLightDistanceAttenuation;
-    lightInput.spotDirection = _MainLightSpotDir;
-    lightInput.spotAttenuation = _MainLightSpotAttenuation;
-
-    half4 directionAndRealtimeAttenuation = GetMainLightDirectionAndAttenuation(lightInput, positionWS);
-
-    light.direction = directionAndRealtimeAttenuation.xyz;
-    light.attenuation = directionAndRealtimeAttenuation.w;
-    light.subtractiveModeAttenuation = lightInput.distanceAttenuation.w;
-    light.color = lightInput.color;
+    light.direction = _MainLightPosition.xyz;
+    light.attenuation = 1.0;
+    light.subtractiveModeAttenuation = _MainLightPosition.w;
+    light.color = _MainLightColor.rgb;
 
     return light;
 }
     BRDFData brdfData;
     InitializeBRDFData(albedo, metallic, specular, smoothness, alpha, brdfData);
 
-    Light mainLight = GetMainLight(inputData.positionWS);
-
-    mainLight.attenuation *= RealtimeShadowAttenuation(inputData.shadowCoord);
+    Light mainLight = GetMainLight();
+    mainLight.attenuation = RealtimeShadowAttenuation(inputData.shadowCoord, 0.0);
 
     MixRealtimeAndBakedGI(mainLight, inputData.normalWS, inputData.bakedGI, half4(0, 0, 0, 0));
     half3 color = GlobalIllumination(brdfData, inputData.bakedGI, occlusion, inputData.normalWS, inputData.viewDirectionWS);
 
 half4 LightweightFragmentBlinnPhong(InputData inputData, half3 diffuse, half4 specularGloss, half shininess, half3 emission, half alpha)
 {
-    Light mainLight = GetMainLight(inputData.positionWS);
-    mainLight.attenuation *= RealtimeShadowAttenuation(inputData.shadowCoord);
+    Light mainLight = GetMainLight();
+    mainLight.attenuation = RealtimeShadowAttenuation(inputData.shadowCoord, 0.0);
     MixRealtimeAndBakedGI(mainLight, inputData.normalWS, inputData.bakedGI, half4(0, 0, 0, 0));
 
     half3 attenuatedLightColor = mainLight.color * mainLight.attenuation;

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/LightweightPassLit.hlsl

 {
     float2 uv                       : TEXCOORD0;
     DECLARE_LIGHTMAP_OR_SH(lightmapUV, vertexSH, 1);
-    float4 posWSShininess           : TEXCOORD2;    // xyz: posWS, w: Shininess * 128
+#ifdef _ADDITIONAL_LIGHTS
+    float3 posWS                    : TEXCOORD2;
+#endif
 
 #ifdef _NORMALMAP
     half4 normal                    : TEXCOORD3;    // xyz: normal, w: viewDir.x
 
 void InitializeInputData(LightweightVertexOutput IN, half3 normalTS, out InputData inputData)
 {
-    inputData.positionWS = IN.posWSShininess.xyz;
+    inputData = (InputData)0;
+
+#ifdef _ADDITIONAL_LIGHTS
+    inputData.positionWS = IN.posWS;
+#endif
 
 #ifdef _NORMALMAP
     half3 viewDir = half3(IN.normal.w, IN.tangent.w, IN.binormal.w);
 
     o.uv = TransformMainTextureCoord(v.texcoord);
 
-    o.posWSShininess.xyz = TransformObjectToWorld(v.vertex.xyz);
-    o.clipPos = TransformWorldToHClip(o.posWSShininess.xyz);
+    float3 posWS = TransformObjectToWorld(v.vertex.xyz);
+    o.clipPos = TransformWorldToHClip(posWS);
-    half3 viewDir = VertexViewDirWS(GetCameraPositionWS() - o.posWSShininess.xyz);
+    half3 viewDir = VertexViewDirWS(GetCameraPositionWS() - posWS);
 
 #ifdef _NORMALMAP
     o.normal.w = viewDir.x;
     OUTPUT_LIGHTMAP_UV(v.lightmapUV, unity_LightmapST, o.lightmapUV);
     OUTPUT_SH(o.normal.xyz, o.vertexSH);
 
-    half3 vertexLight = VertexLighting(o.posWSShininess.xyz, o.normal.xyz);
+    half3 vertexLight = VertexLighting(posWS, o.normal.xyz);
     half fogFactor = ComputeFogFactor(o.clipPos.z);
     o.fogFactorAndVertexLight = half4(fogFactor, vertexLight);
 
 #else
-    o.shadowCoord = TransformWorldToShadowCoord(o.posWSShininess.xyz);
+    o.shadowCoord = TransformWorldToShadowCoord(posWS);
+#if _ADDITIONAL_LIGHTS
+    o.posWS = posWS;
+#endif
+
     return o;
 }
 
     ApplyFog(color.rgb, inputData.fogCoord);
     return color;
 }
-
-// Used in Standard (Simple Lighting) shader
-// TODO: we only need to specialise this because of _Shininess prop
-// Once we refactor SimpleLighting shader we will be able to share vertex
-// between PBS and Simple
-LightweightVertexOutput LitPassVertexSimple(LightweightVertexInput v)
-{
-    LightweightVertexOutput o = (LightweightVertexOutput)0;
-
-    UNITY_SETUP_INSTANCE_ID(v);
-    UNITY_TRANSFER_INSTANCE_ID(v, o);
-    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
-
-    o.uv = TransformMainTextureCoord(v.texcoord);
-
-    o.posWSShininess.xyz = TransformObjectToWorld(v.vertex.xyz);
-    o.posWSShininess.w = _Shininess * 128.0;
-    o.clipPos = TransformWorldToHClip(o.posWSShininess.xyz);
-
-    half3 viewDir = VertexViewDirWS(GetCameraPositionWS() - o.posWSShininess.xyz);
-
-#ifdef _NORMALMAP
-    o.normal.w = viewDir.x;
-    o.tangent.w = viewDir.y;
-    o.binormal.w = viewDir.z;
-#else
-    o.viewDir = viewDir;
-#endif
-
-    // initializes o.normal and if _NORMALMAP also o.tangent and o.binormal
-    OUTPUT_NORMAL(v, o);
-
-    // We either sample GI from lightmap or SH.
-    // Lightmap UV and vertex SH coefficients use the same interpolator ("float2 lightmapUV" for lightmap or "half3 vertexSH" for SH)
-    // see DECLARE_LIGHTMAP_OR_SH macro.
-    // The following funcions initialize the correct variable with correct data
-    OUTPUT_LIGHTMAP_UV(v.lightmapUV, unity_LightmapST, o.lightmapUV);
-    OUTPUT_SH(o.normal.xyz, o.vertexSH);
-
-    half3 vertexLight = VertexLighting(o.posWSShininess.xyz, o.normal.xyz);
-    half fogFactor = ComputeFogFactor(o.clipPos.z);
-    o.fogFactorAndVertexLight = half4(fogFactor, vertexLight);
-
-#ifdef _SHADOWS_ENABLED
-#if SHADOWS_SCREEN
-    o.shadowCoord = ComputeShadowCoord(o.clipPos);
-#else
-    o.shadowCoord = TransformWorldToShadowCoord(o.posWSShininess.xyz);
-#endif
-#endif
-
-    return o;
-}
-
-// Used for StandardSimpleLighting shader
-half4 LitPassFragmentSimple(LightweightVertexOutput IN) : SV_Target
-{
-    UNITY_SETUP_INSTANCE_ID(IN);
-
-    float2 uv = IN.uv;
-    half4 diffuseAlpha = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, uv);
-    half3 diffuse = diffuseAlpha.rgb * _Color.rgb;
-
-    half alpha = diffuseAlpha.a * _Color.a;
-    AlphaDiscard(alpha, _Cutoff);
-#ifdef _ALPHAPREMULTIPLY_ON
-    diffuse *= alpha;
-#endif
-
-#ifdef _NORMALMAP
-    half3 normalTS = Normal(uv);
-#else
-    half3 normalTS = half3(0, 0, 1);
-#endif
-
-    half3 emission = Emission(uv);
-    half4 specularGloss = SpecularGloss(uv, diffuseAlpha.a);
-    half shininess = IN.posWSShininess.w;
-
-    InputData inputData;
-    InitializeInputData(IN, normalTS, inputData);
-
-    return LightweightFragmentBlinnPhong(inputData, diffuse, specularGloss, shininess, emission, alpha);
-};
 
 #endif

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/Shadows.hlsl

     return attenuation;
 }
 
-inline real SampleShadowmap(float4 shadowCoord)
+inline real SampleShadowmap(float4 shadowCoord, float isPerspectiveProjection = 1.0)
-    shadowCoord.xyz /= shadowCoord.w;
+    if (isPerspectiveProjection == 0.0)
+        shadowCoord.xyz /= shadowCoord.w;
 
     real attenuation;
 
     return ComputeScreenPos(clipPos);
 }
 
-half RealtimeShadowAttenuation(float4 shadowCoord)
+half RealtimeShadowAttenuation(float4 shadowCoord, float isPerspectiveProjection = 1.0)
 {
 #ifndef _SHADOWS_ENABLED
     return 1.0h;
     return SampleScreenSpaceShadowMap(shadowCoord);
 #else
 
-    return SampleShadowmap(shadowCoord);
+    return SampleShadowmap(shadowCoord, isPerspectiveProjection);
 #endif
 }
 

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/LightweightScreenSpaceShadows.shader

             //Fetch shadow coordinates for cascade.
             float4 coords  = TransformWorldToShadowCoord(wpos);
 
-            return SampleShadowmap(coords);
+            // Screenspace shadowmap is only used for directional lights which use orthogonal projection.
+            return SampleShadowmap(coords, 0.0);
         }
 
         ENDHLSL

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/LightweightStandardSimpleLighting.shader

             #pragma vertex LitPassVertexSimple
             #pragma fragment LitPassFragmentSimple
             #define BUMP_SCALE_NOT_SUPPORTED 1
-            #include "LWRP/ShaderLibrary/LightweightPassLit.hlsl"
+            #include "LWRP/ShaderLibrary/LightweightPassLitSimple.hlsl"
             ENDHLSL
         }
 

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/LightweightPassLitSimple.hlsl

+#ifndef LIGHTWEIGHT_PASS_LIT_INCLUDED
+#define LIGHTWEIGHT_PASS_LIT_INCLUDED
+
+#include "LWRP/ShaderLibrary/InputSurface.hlsl"
+#include "LWRP/ShaderLibrary/Lighting.hlsl"
+
+struct LightweightVertexInput
+{
+    float4 vertex : POSITION;
+    float3 normal : NORMAL;
+    float4 tangent : TANGENT;
+    float2 texcoord : TEXCOORD0;
+    float2 lightmapUV : TEXCOORD1;
+    UNITY_VERTEX_INPUT_INSTANCE_ID
+};
+
+struct LightweightVertexOutput
+{
+    float2 uv                       : TEXCOORD0;
+    DECLARE_LIGHTMAP_OR_SH(lightmapUV, vertexSH, 1);
+
+    float4 posWSShininess           : TEXCOORD2;    // xyz: posWS, w: Shininess * 128
+
+#ifdef _NORMALMAP
+    half4 normal                    : TEXCOORD3;    // xyz: normal, w: viewDir.x
+    half4 tangent                   : TEXCOORD4;    // xyz: tangent, w: viewDir.y
+    half4 binormal                  : TEXCOORD5;    // xyz: binormal, w: viewDir.z
+#else
+    half3  normal                   : TEXCOORD3;
+    half3 viewDir                   : TEXCOORD4;
+#endif
+
+    half4 fogFactorAndVertexLight   : TEXCOORD6; // x: fogFactor, yzw: vertex light
+
+#ifdef _SHADOWS_ENABLED
+    float4 shadowCoord              : TEXCOORD7;
+#endif
+
+    float4 clipPos                  : SV_POSITION;
+    UNITY_VERTEX_INPUT_INSTANCE_ID
+    UNITY_VERTEX_OUTPUT_STEREO
+};
+
+void InitializeInputData(LightweightVertexOutput IN, half3 normalTS, out InputData inputData)
+{
+    inputData.positionWS = IN.posWSShininess.xyz;
+
+#ifdef _NORMALMAP
+    half3 viewDir = half3(IN.normal.w, IN.tangent.w, IN.binormal.w);
+    inputData.normalWS = TangentToWorldNormal(normalTS, IN.tangent.xyz, IN.binormal.xyz, IN.normal.xyz);
+#else
+    half3 viewDir = IN.viewDir;
+    inputData.normalWS = FragmentNormalWS(IN.normal);
+#endif
+
+    inputData.viewDirectionWS = FragmentViewDirWS(viewDir);
+#ifdef _SHADOWS_ENABLED
+    inputData.shadowCoord = IN.shadowCoord;
+#else
+    inputData.shadowCoord = float4(0, 0, 0, 0);
+#endif
+    inputData.fogCoord = IN.fogFactorAndVertexLight.x;
+    inputData.vertexLighting = IN.fogFactorAndVertexLight.yzw;
+    inputData.bakedGI = SAMPLE_GI(IN.lightmapUV, IN.vertexSH, inputData.normalWS);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+//                  Vertex and Fragment functions                            //
+///////////////////////////////////////////////////////////////////////////////
+
+// Used in Standard (Simple Lighting) shader
+LightweightVertexOutput LitPassVertexSimple(LightweightVertexInput v)
+{
+    LightweightVertexOutput o = (LightweightVertexOutput)0;
+
+    UNITY_SETUP_INSTANCE_ID(v);
+    UNITY_TRANSFER_INSTANCE_ID(v, o);
+    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
+
+    o.uv = TransformMainTextureCoord(v.texcoord);
+
+    o.posWSShininess.xyz = TransformObjectToWorld(v.vertex.xyz);
+    o.posWSShininess.w = _Shininess * 128.0;
+    o.clipPos = TransformWorldToHClip(o.posWSShininess.xyz);
+
+    half3 viewDir = VertexViewDirWS(GetCameraPositionWS() - o.posWSShininess.xyz);
+
+#ifdef _NORMALMAP
+    o.normal.w = viewDir.x;
+    o.tangent.w = viewDir.y;
+    o.binormal.w = viewDir.z;
+#else
+    o.viewDir = viewDir;
+#endif
+
+    // initializes o.normal and if _NORMALMAP also o.tangent and o.binormal
+    OUTPUT_NORMAL(v, o);
+
+    // We either sample GI from lightmap or SH.
+    // Lightmap UV and vertex SH coefficients use the same interpolator ("float2 lightmapUV" for lightmap or "half3 vertexSH" for SH)
+    // see DECLARE_LIGHTMAP_OR_SH macro.
+    // The following funcions initialize the correct variable with correct data
+    OUTPUT_LIGHTMAP_UV(v.lightmapUV, unity_LightmapST, o.lightmapUV);
+    OUTPUT_SH(o.normal.xyz, o.vertexSH);
+
+    half3 vertexLight = VertexLighting(o.posWSShininess.xyz, o.normal.xyz);
+    half fogFactor = ComputeFogFactor(o.clipPos.z);
+    o.fogFactorAndVertexLight = half4(fogFactor, vertexLight);
+
+#ifdef _SHADOWS_ENABLED
+#if SHADOWS_SCREEN
+    o.shadowCoord = ComputeShadowCoord(o.clipPos);
+#else
+    o.shadowCoord = TransformWorldToShadowCoord(o.posWSShininess.xyz);
+#endif
+#endif
+
+    return o;
+}
+
+// Used for StandardSimpleLighting shader
+half4 LitPassFragmentSimple(LightweightVertexOutput IN) : SV_Target
+{
+    UNITY_SETUP_INSTANCE_ID(IN);
+
+    float2 uv = IN.uv;
+    half4 diffuseAlpha = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, uv);
+    half3 diffuse = diffuseAlpha.rgb * _Color.rgb;
+
+    half alpha = diffuseAlpha.a * _Color.a;
+    AlphaDiscard(alpha, _Cutoff);
+#ifdef _ALPHAPREMULTIPLY_ON
+    diffuse *= alpha;
+#endif
+
+#ifdef _NORMALMAP
+    half3 normalTS = Normal(uv);
+#else
+    half3 normalTS = half3(0, 0, 1);
+#endif
+
+    half3 emission = Emission(uv);
+    half4 specularGloss = SpecularGloss(uv, diffuseAlpha.a);
+    half shininess = IN.posWSShininess.w;
+
+    InputData inputData;
+    InitializeInputData(IN, normalTS, inputData);
+
+    return LightweightFragmentBlinnPhong(inputData, diffuse, specularGloss, shininess, emission, alpha);
+};
+
+#endif

ScriptableRenderPipeline/LightweightPipeline/LWRP/ShaderLibrary/LightweightPassLitSimple.hlsl.meta

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+guid: ee447e65526c7db45a978c16b28827a9
+timeCreated: 1488965025
+licenseType: Pro
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+  assetBundleName: 
+  assetBundleVariant: