From 1c030377c0c7e1b1df500dee42d4a1a7b0bd1f2c Mon Sep 17 00:00:00 2001
From: Nico de Poel <ndepoel@gmail.com>
Date: Sat, 18 Mar 2023 14:23:50 +0100
Subject: [PATCH] Reshufled some code so that if the initialization process
 fails for some reason, we don't leave the scene behind in a messed up state.

---
 Assets/Scripts/Fsr2ImageEffect.cs | 38 +++++++++++++++++--------------
 1 file changed, 21 insertions(+), 17 deletions(-)

diff --git a/Assets/Scripts/Fsr2ImageEffect.cs b/Assets/Scripts/Fsr2ImageEffect.cs
index 2e7ea37..7077e4f 100644
--- a/Assets/Scripts/Fsr2ImageEffect.cs
+++ b/Assets/Scripts/Fsr2ImageEffect.cs
@@ -69,6 +69,22 @@ namespace FidelityFX
         
         private void OnEnable()
         {
+            // Set up the original camera to output all of the required FSR2 input resources at the desired resolution
+            _renderCamera = GetComponent<Camera>();
+            _originalRenderTarget = _renderCamera.targetTexture;
+            _originalDepthTextureMode = _renderCamera.depthTextureMode;
+            _renderCamera.targetTexture = null;     // Clear the camera's target texture so we can fully control how the output gets written
+            _renderCamera.depthTextureMode = _originalDepthTextureMode | DepthTextureMode.Depth | DepthTextureMode.MotionVectors;
+            
+            // Determine the desired rendering and display resolutions
+            _displaySize = new Vector2Int(_renderCamera.pixelWidth, _renderCamera.pixelHeight);
+            Fsr2.GetRenderResolutionFromQualityMode(out var renderWidth, out var renderHeight, _displaySize.x, _displaySize.y, qualityMode);
+            _renderSize = new Vector2Int(renderWidth, renderHeight);
+            
+            // Apply a mipmap bias so that textures retain their sharpness
+            float biasOffset = Fsr2.GetMipmapBiasOffset(_renderSize.x, _displaySize.x);
+            Fsr2.GlobalCallbacks.ApplyMipmapBias(biasOffset);
+            
             if (!SystemInfo.supportsComputeShaders)
             {
                 Debug.LogError("FSR2 requires compute shader support!");
@@ -78,22 +94,12 @@ namespace FidelityFX
             
             _helper = GetComponent<Fsr2ImageEffectHelper>();
             
-            // Set up the original camera to output all of the required FSR2 input resources at the desired resolution
-            _renderCamera = GetComponent<Camera>();
-            _originalRenderTarget = _renderCamera.targetTexture;
-            _originalDepthTextureMode = _renderCamera.depthTextureMode;
-            _renderCamera.targetTexture = null;     // Clear the camera's target texture so we can fully control how the output gets written
-            _renderCamera.depthTextureMode = _originalDepthTextureMode | DepthTextureMode.Depth | DepthTextureMode.MotionVectors;
-            
             // Initialize FSR2 context
             Fsr2.InitializationFlags flags = 0;
             if (_renderCamera.allowHDR) flags |= Fsr2.InitializationFlags.EnableHighDynamicRange;
             if (enableFP16) flags |= Fsr2.InitializationFlags.EnableFP16Usage;
             if (enableAutoExposure) flags |= Fsr2.InitializationFlags.EnableAutoExposure;
 
-            _displaySize = new Vector2Int(_renderCamera.pixelWidth, _renderCamera.pixelHeight);
-            Fsr2.GetRenderResolutionFromQualityMode(out var renderWidth, out var renderHeight, _displaySize.x, _displaySize.y, qualityMode);
-            _renderSize = new Vector2Int(renderWidth, renderHeight);
             _context = Fsr2.CreateContext(_displaySize, _renderSize, flags);
 
             _dispatchCommandBuffer = new CommandBuffer { name = "FSR2 Dispatch" };
@@ -108,10 +114,6 @@ namespace FidelityFX
                 _renderCamera.AddCommandBuffer(CameraEvent.BeforeForwardAlpha, _opaqueInputCommandBuffer);
             }
 
-            // Apply a mipmap bias so that textures retain their sharpness
-            float biasOffset = Fsr2.GetMipmapBiasOffset(_renderSize.x, _displaySize.x);
-            Fsr2.GlobalCallbacks.ApplyMipmapBias(biasOffset);
-
             _prevDisplaySize = _displaySize;
             _prevQualityMode = qualityMode;
             _prevGenReactiveMask = autoGenerateReactiveMask;
@@ -119,8 +121,13 @@ namespace FidelityFX
 
         private void OnDisable()
         {
+            // Undo the current mipmap bias offset
             float biasOffset = Fsr2.GetMipmapBiasOffset(_renderSize.x, _prevDisplaySize.x);
             Fsr2.GlobalCallbacks.ApplyMipmapBias(-biasOffset);
+            
+            // Restore the camera's original state
+            _renderCamera.depthTextureMode = _originalDepthTextureMode;
+            _renderCamera.targetTexture = _originalRenderTarget;
 
             if (_opaqueInputCommandBuffer != null)
             {
@@ -135,9 +142,6 @@ namespace FidelityFX
                 _dispatchCommandBuffer = null;
             }
 
-            _renderCamera.depthTextureMode = _originalDepthTextureMode;
-            _renderCamera.targetTexture = _originalRenderTarget;
-            
             if (_context != null)
             {
                 _context.Destroy();