Merge pull request #84 from Unity-Technologies/Fix-baked-lightmap-rgbm

Moved enlighten emissive RGBM stuff into EntityLighting.hlsl

Assets/ScriptableRenderLoop/HDRenderPipeline/ShaderPass/ShaderPassLightTransport.hlsl

 
 #include "Color.hlsl"
 
-// TODO: This is the max value allowed for emissive (bad name - but keep for now to retrieve it) (It is 8^2.2 (gamma) and 8 is the limit of punctual light slider...), comme from UnityCg.cginc. Fix it!
-// Ask Jesper if this can be change for HDRenderPipeline
-#define EMISSIVE_RGBM_SCALE 97.0
-
 float4 Frag(PackedVaryings packedInput) : SV_Target
 {
     FragInputs input = UnpackVaryings(packedInput);
     {
         // TODO: THIS LIMIT MUST BE REMOVE, IT IS NOT HDR, change when RGB9e5 is here.
         // Do we assume here that emission is [0..1] ?
-        res = PackRGBM(lightTransportData.emissiveColor, EMISSIVE_RGBM_SCALE);
+        res = PackEmissiveRGBM(lightTransportData.emissiveColor);
     }
 
     return res;

Assets/ScriptableRenderLoop/ShaderLibrary/EntityLighting.hlsl

 }
 
 // Following functions are to sample enlighten lightmaps (or lightmaps encoded the same way as our
-// enlighten implementation). They assume use of RGB9E5 for illuminance map.
+// enlighten implementation). They assume use of RGB9E5 for dynamic illuminance map and RGBM for baked ones.
+// TODO: This is the max value allowed for emissive (bad name - but keep for now to retrieve it) (It is 8^2.2 (gamma) and 8 is the limit of punctual light slider...), comme from UnityCg.cginc. Fix it!
+// Ask Jesper if this can be change for HDRenderPipeline
+#define EMISSIVE_RGBM_SCALE 97.0
-// This is temporary. For now baked lightmap are in RGBM and the RGBM range for lightmaps is specific so we can't use the generic method.
+// RGBM stuff is temporary. For now baked lightmap are in RGBM and the RGBM range for lightmaps is specific so we can't use the generic method.
+// Same goes for emissive packed as an input for Enlighten with another hard coded multiplier.
+
+// TODO: This function is used with the LightTransport pass to encode lightmap or emissive
+float4 PackEmissiveRGBM(float3 rgb)
+{
+    float kOneOverRGBMMaxRange = 1.0 / EMISSIVE_RGBM_SCALE;
+    const float kMinMultiplier = 2.0 * 1e-2;
+
+    float4 rgbm = float4(rgb * kOneOverRGBMMaxRange, 1.0);
+        rgbm.a = max(max(rgbm.r, rgbm.g), max(rgbm.b, kMinMultiplier));
+    rgbm.a = ceil(rgbm.a * 255.0) / 255.0;
+
+    // Division-by-zero warning from d3d9, so make compiler happy.
+    rgbm.a = max(rgbm.a, kMinMultiplier);
+
+    rgbm.rgb /= rgbm.a;
+    return rgbm;
+}
+
 float3 UnpackLightmapRGBM(float4 rgbmInput)
 {
     return rgbmInput.rgb * rgbmInput.a * LIGHTMAP_RGBM_RANGE;

Assets/ScriptableRenderLoop/ShaderLibrary/Packing.hlsl

     return max(vRGB, float3(0.0, 0.0, 0.0));
 }
 
-// TODO: This function is used with the LightTransport pass to encode lightmap or emissive
-float4 PackRGBM(float3 rgb, float maxRGBM)
-{
-    float kOneOverRGBMMaxRange = 1.0 / maxRGBM;
-    const float kMinMultiplier = 2.0 * 1e-2;
-
-    float4 rgbm = float4(rgb * kOneOverRGBMMaxRange, 1.0);
-    rgbm.a = max(max(rgbm.r, rgbm.g), max(rgbm.b, kMinMultiplier));
-    rgbm.a = ceil(rgbm.a * 255.0) / 255.0;
-
-    // Division-by-zero warning from d3d9, so make compiler happy.
-    rgbm.a = max(rgbm.a, kMinMultiplier);
-
-    rgbm.rgb /= rgbm.a;
-    return rgbm;
-}
-
 // Alternative...
 #define RGBMRANGE (8.0)
 float4 PackRGBM(float3 color)