Use original camera pixel width and height to determine display size, so that cameras with non-standard viewport rects will work too.

Assets/Scripts/Fsr2Controller.cs

@@ -60,6 +60,12 @@ 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>();
+            _originalDepthTextureMode = _renderCamera.depthTextureMode;
+            _renderCamera.depthTextureMode = _originalDepthTextureMode | DepthTextureMode.Depth | DepthTextureMode.MotionVectors;
+            
+            // Initialize FSR2 context
             Fsr2.InitializationFlags flags = 0;
             if (enableFP16)
                 flags |= Fsr2.InitializationFlags.EnableFP16Usage;
@@ -68,16 +74,11 @@ namespace FidelityFX
             flags |= Fsr2.InitializationFlags.EnableDebugChecking;
 #endif
             
-            _displaySize = new Vector2Int(Screen.width, Screen.height);
+            _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);
 
-            // Set up the original camera to output all of the required FSR2 input resources at the desired resolution
-            _renderCamera = GetComponent<Camera>();
-            _originalDepthTextureMode = _renderCamera.depthTextureMode;
-            _renderCamera.depthTextureMode = _originalDepthTextureMode | DepthTextureMode.Depth | DepthTextureMode.MotionVectors;
-            
             _dispatchCommandBuffer = new CommandBuffer { name = "FSR2 Dispatch" };
 
             // Create command buffers to bind the camera's output at the right moments in the render loop
@@ -141,7 +142,7 @@ namespace FidelityFX
 
         private void Update()
         {
-            if (Screen.width != _prevDisplaySize.x || Screen.height != _prevDisplaySize.y || qualityMode != _prevQualityMode)
+            if (_renderCamera.pixelWidth != _prevDisplaySize.x || _renderCamera.pixelHeight != _prevDisplaySize.y || qualityMode != _prevQualityMode)
             {
                 // Force all resources to be destroyed and recreated with the new settings
                 OnDisable();
@@ -168,7 +169,7 @@ namespace FidelityFX
         {
             // Render to a smaller portion of the screen by manipulating the camera's viewport rect
             _originalRect = _renderCamera.rect;
-            _renderCamera.aspect = (Screen.width * _originalRect.width) / (Screen.height * _originalRect.height);
+            _renderCamera.aspect = (_renderCamera.pixelWidth * _originalRect.width) / (_renderCamera.pixelHeight * _originalRect.height);
             _renderCamera.rect = new Rect(0, 0, _originalRect.width * _renderSize.x / _displaySize.x, _originalRect.height * _renderSize.y / _displaySize.y);
 
             // Set up the parameters to auto-generate a reactive mask
@@ -266,7 +267,7 @@ namespace FidelityFX
             else
             {
                 // We are rendering to the backbuffer, so we need a temporary render texture for FSR2 to output to
-                _dispatchCommandBuffer.GetTemporaryRT(Fsr2Pipeline.UavUpscaledOutput, Screen.width, Screen.height, 0, default, GraphicsFormat.R16G16B16A16_SFloat, 1, true);
+                _dispatchCommandBuffer.GetTemporaryRT(Fsr2Pipeline.UavUpscaledOutput, _displaySize.x, _displaySize.y, 0, default, GraphicsFormat.R16G16B16A16_SFloat, 1, true);
             }
 
             _context.Dispatch(_dispatchDescription, _dispatchCommandBuffer);