From 537d96d3b67d371efaba453b402ad4ad4d4d99ab Mon Sep 17 00:00:00 2001
From: Nico de Poel <ndepoel@gmail.com>
Date: Fri, 2 Jun 2023 12:36:19 +0200
Subject: [PATCH] Explicitly create and destroy the opaque-only RT before and
 after rendering, so that it remains valid throughout. Fixes the ESRAM-related
 visual jittering issue on Xbox One when auto-reactive or auto-TCR is enabled.

---
 Assets/Scripts/Fsr2ImageEffect.cs | 25 +++++++++++++++----------
 README.md                         |  5 +----
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/Assets/Scripts/Fsr2ImageEffect.cs b/Assets/Scripts/Fsr2ImageEffect.cs
index 7ee9ca3..3dfc2ea 100644
--- a/Assets/Scripts/Fsr2ImageEffect.cs
+++ b/Assets/Scripts/Fsr2ImageEffect.cs
@@ -120,6 +120,7 @@ namespace FidelityFX
 
         private CommandBuffer _dispatchCommandBuffer;
         private CommandBuffer _opaqueInputCommandBuffer;
+        private RenderTexture _colorOpaqueOnly;
 
         private Material _copyWithDepthMaterial;
 
@@ -169,11 +170,7 @@ namespace FidelityFX
             _context = Fsr2.CreateContext(_displaySize, _renderSize, Callbacks, flags);
 
             _dispatchCommandBuffer = new CommandBuffer { name = "FSR2 Dispatch" };
-
-            // Create command buffers to bind the camera's output at the right moments in the render loop
             _opaqueInputCommandBuffer = new CommandBuffer { name = "FSR2 Opaque Input" };
-            _opaqueInputCommandBuffer.GetTemporaryRT(Fsr2ShaderIDs.SrvOpaqueOnly, _renderSize.x, _renderSize.y, 0, default, GetDefaultFormat());
-            _opaqueInputCommandBuffer.Blit(BuiltinRenderTextureType.CameraTarget, Fsr2ShaderIDs.SrvOpaqueOnly);
 
             if (autoGenerateReactiveMask || autoGenerateTransparencyAndComposition)
             {
@@ -268,11 +265,18 @@ namespace FidelityFX
                 _renderCamera.aspect = (_displaySize.x * _originalRect.width) / (_displaySize.y * _originalRect.height);
                 _renderCamera.rect = new Rect(0, 0, _originalRect.width * _renderSize.x / _renderCamera.pixelWidth, _originalRect.height * _renderSize.y / _renderCamera.pixelHeight);
             }
+            
+            _opaqueInputCommandBuffer.Clear();
+            if (autoGenerateReactiveMask || autoGenerateTransparencyAndComposition)
+            {
+                _colorOpaqueOnly = RenderTexture.GetTemporary(_renderSize.x, _renderSize.y, 0, GetDefaultFormat());
+                _opaqueInputCommandBuffer.Blit(BuiltinRenderTextureType.CameraTarget, _colorOpaqueOnly);
+            }
 
             // Set up the parameters to auto-generate a reactive mask
             if (autoGenerateReactiveMask)
             {
-                _genReactiveDescription.ColorOpaqueOnly = null;
+                _genReactiveDescription.ColorOpaqueOnly = _colorOpaqueOnly;
                 _genReactiveDescription.ColorPreUpscale = null;
                 _genReactiveDescription.OutReactive = null;
                 _genReactiveDescription.RenderSize = _renderSize;
@@ -313,6 +317,7 @@ namespace FidelityFX
             _dispatchDescription.EnableAutoReactive = autoGenerateTransparencyAndComposition;
             if (autoGenerateTransparencyAndComposition)
             {
+                _dispatchDescription.ColorOpaqueOnly = _colorOpaqueOnly;
                 _dispatchDescription.AutoTcThreshold = generateTransparencyAndCompositionParameters.autoTcThreshold;
                 _dispatchDescription.AutoTcScale = generateTransparencyAndCompositionParameters.autoTcScale;
                 _dispatchDescription.AutoReactiveScale = generateTransparencyAndCompositionParameters.autoReactiveScale;
@@ -358,7 +363,6 @@ namespace FidelityFX
             {
                 _dispatchCommandBuffer.GetTemporaryRT(Fsr2ShaderIDs.UavAutoReactive, _renderSize.x, _renderSize.y, 0, default, GraphicsFormat.R8_UNorm, 1, true);
                 _context.GenerateReactiveMask(_genReactiveDescription, _dispatchCommandBuffer);
-                _dispatchCommandBuffer.ReleaseTemporaryRT(Fsr2ShaderIDs.SrvOpaqueOnly);
                 
                 _dispatchDescription.Reactive = Fsr2ShaderIDs.UavAutoReactive;
             }
@@ -390,13 +394,14 @@ namespace FidelityFX
                 _dispatchCommandBuffer.ReleaseTemporaryRT(Fsr2ShaderIDs.UavAutoReactive);
             }
 
-            if (autoGenerateTransparencyAndComposition)
+            Graphics.ExecuteCommandBuffer(_dispatchCommandBuffer);
+            
+            if (_colorOpaqueOnly != null)
             {
-                _dispatchCommandBuffer.ReleaseTemporaryRT(Fsr2ShaderIDs.SrvOpaqueOnly);
+                RenderTexture.ReleaseTemporary(_colorOpaqueOnly);
+                _colorOpaqueOnly = null;
             }
 
-            Graphics.ExecuteCommandBuffer(_dispatchCommandBuffer);
-
             // Shut up the Unity warning about not writing to the destination texture 
             RenderTexture.active = dest;
         }
diff --git a/README.md b/README.md
index 6caa5c9..60b4e4e 100644
--- a/README.md
+++ b/README.md
@@ -125,11 +125,8 @@ The exposure value can be supplied to the `Fsr2ImageEffect` script through its E
 ## Known issues
 
 - Enabling Auto Exposure causes artifacting on OpenGL Core.  
-  It's uncertain what is causing this. Further investigation is required.
+  It's uncertain what is causing this. Further investigation is required.  
   Workaround: disable Auto Exposure on affected platforms.
-- Auto Reactive Mask causes jitter artifacting on Xbox One when ESRAM is enabled.  
-  This is due to some kind of issue in Unity related to render texture blitting. For unknown reasons the opaque-only render buffer used as reference for generating the reactive mask has an incorrect jitter offset (possibly it's a render buffer from a previous frame), causing the reactive mask to be incorrect as well.  
-  Workaround: either disable ESRAM usage or disable the Auto Generate Reactive Mask feature.
 - Texture mipmap bias adjustment is not working on MacOS Metal.  
   This causes blurry textures as the internal render resolution is lowered. This is a Unity issue of some sort.  
   Workaround: no known workaround yet.