Fixed negative values in color grading

Author: Chman

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to this package will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [2.1.3] - 2018-xx-xx
+
+### Fixed
+- Color grading would output negative values in some cases and break rendering on some platforms.
+
 ## [2.1.2] - 2018-12-05
 
 ### Fixed

PostProcessing/Shaders/Builtins/Lut2DBaker.shader

@@ -179,7 +179,7 @@ Shader "Hidden/PostProcessing/Lut2DBaker"
         {
             float3 colorLutSpace = GetLutStripValue(i.texcoord, _Lut2D_Params);
             float3 graded = ColorGradeHDR(colorLutSpace);
-            return float4(graded, 1.0);
+            return float4(max(graded, 0.0), 1.0);
         }
 
     ENDHLSL

PostProcessing/Shaders/Builtins/Lut3DBaker.compute

@@ -147,7 +147,7 @@ void Eval(uint3 id)
         // Color grade & tonemap
         float3 graded = ColorGrade(colorLutSpace);
 
-        _Output[id] = float4(graded, 1.0);
+        _Output[id] = float4(max(graded, 0.0), 1.0);
     }
 }