Fixed copy materials being recreated on every frame (#1182118)

Author: Chman

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Fixed
 - Potential fp16 overflow in Depth of Field that could cause NaN on some platforms.
 - Error with Screen-space Reflections when HDR is disabled.
+- Internal "copy" materials were recreated on every frame after the asset bundle-related fix from 2.1.7.
 
 ## [2.1.7] - 2019-06-12
 

PostProcessing/Runtime/PostProcessLayer.cs

@@ -120,6 +120,10 @@ public enum Antialiasing
         [SerializeField]
         PostProcessResources m_Resources;
 
+        // Some juggling needed to track down reference to the resource asset when loaded from asset
+        // bundle (guid conflict)
+        PostProcessResources m_OldResources;
+
         // UI states
 #if UNITY_2017_1_OR_NEWER
         [UnityEngine.Scripting.Preserve]
@@ -804,7 +808,13 @@ public bool HasActiveEffects(PostProcessEvent evt, PostProcessRenderContext cont
 
         void SetupContext(PostProcessRenderContext context)
         {
-            RuntimeUtilities.UpdateResources(m_Resources);
+            // Juggling required when a scene with post processing is loaded from an asset bundle
+            // See #1148230
+            if (m_OldResources != m_Resources)
+            {
+                RuntimeUtilities.UpdateResources(m_Resources);
+                m_OldResources = m_Resources;
+            }
 
             m_IsRenderingInSceneView = context.camera.cameraType == CameraType.SceneView;
             context.isSceneView = m_IsRenderingInSceneView;