Merge pull request #771 from Unity-Technologies/fix_mali_color_grading_on_gles2

Fixed case 1127107. No more banding with Color grading on ES2 on Mali!

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).
 
+## [2.1.5] - 2019-xx-xx
+
+### Fixed
+- LDR Color grading in gamma mode no longer produces banding artifacts on Mali GPUs on OpenGL ES2.
+
 ## [2.1.4] - 2019-02-27
 
 ### Fixed

PostProcessing/Runtime/Effects/ColorGrading.cs

@@ -1,5 +1,7 @@
 using System;
 
+using UnityEngine.Experimental.Rendering;
+
 namespace UnityEngine.Rendering.PostProcessing
 {
     /// <summary>
@@ -779,19 +781,25 @@ Texture2D GetCurveTexture(bool hdr)
             return m_GradingCurves;
         }
 
+        static bool IsRenderTextureFormatSupportedForLinearFiltering(RenderTextureFormat format)
+        {
+            var gFormat = GraphicsFormatUtility.GetGraphicsFormat(format, RenderTextureReadWrite.Linear);
+            return SystemInfo.IsFormatSupported(gFormat, FormatUsage.Linear);
+        }
+
         static RenderTextureFormat GetLutFormat()
         {
             // Use ARGBHalf if possible, fallback on ARGB2101010 and ARGB32 otherwise
             var format = RenderTextureFormat.ARGBHalf;
 
-            if (!format.IsSupported())
+            if (!IsRenderTextureFormatSupportedForLinearFiltering(format))
             {
                 format = RenderTextureFormat.ARGB2101010;
 
                 // Note that using a log lut in ARGB32 is a *very* bad idea but we need it for
                 // compatibility reasons (else if a platform doesn't support one of the previous
                 // format it'll output a black screen, or worse will segfault on the user).
-                if (!format.IsSupported())
+                if (!IsRenderTextureFormatSupportedForLinearFiltering(format))
                     format = RenderTextureFormat.ARGB32;
             }