From 178d9131af86ab2bd78e958323ecd24597c93168 Mon Sep 17 00:00:00 2001
From: Nico de Poel <ndepoel@gmail.com>
Date: Thu, 9 Mar 2023 15:59:04 +0100
Subject: [PATCH] Implemented most of the FSR2 dispatch. It seems to be doing
 the right things in the background. Now its output just needs to be hacked
 into the PPV2 pipeline correctly.

---
 Assets/Scripts/Fsr2PostProcessEffect.cs | 64 +++++++++++++++++++++++--
 1 file changed, 61 insertions(+), 3 deletions(-)

diff --git a/Assets/Scripts/Fsr2PostProcessEffect.cs b/Assets/Scripts/Fsr2PostProcessEffect.cs
index 19b9259..cc20c54 100644
--- a/Assets/Scripts/Fsr2PostProcessEffect.cs
+++ b/Assets/Scripts/Fsr2PostProcessEffect.cs
@@ -3,6 +3,7 @@ using System;
 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
+using UnityEngine.Rendering;
 using UnityEngine.Rendering.PostProcessing;
 
 namespace FidelityFX
@@ -63,6 +64,9 @@ namespace FidelityFX
         private ref Vector2Int DisplaySize => ref _helper.DisplaySize;
         private ref Vector2Int RenderSize => ref _helper.RenderSize;
         
+        private readonly Fsr2.DispatchDescription _dispatchDescription = new Fsr2.DispatchDescription();
+        private readonly Fsr2.GenerateReactiveDescription _genReactiveDescription = new Fsr2.GenerateReactiveDescription();
+        
         private Fsr2.QualityMode _prevQualityMode;
         private Vector2Int _prevDisplaySize;
         
@@ -119,11 +123,26 @@ namespace FidelityFX
                 _prevQualityMode = settings.qualityMode;
             }
 
-            //Debug.Log("[FSR2] Render, where am I being called from?");  // In OnPreCull... OH
-            // TODO: executing in OnPreCull means we can do jittering in here, at least. Rect manipulation should still happen before PPV2 entirely.
+            // Effects rendering happens in OnPreCull, so this is the right place to apply camera jittering
             ApplyJitter(context.camera);
             
-            cmd.BlitFullscreenTriangle(context.source, context.destination);
+            cmd.SetGlobalTexture(Fsr2Pipeline.SrvInputColor, context.source, RenderTextureSubElement.Color);
+            cmd.SetGlobalTexture(Fsr2Pipeline.SrvInputDepth, BuiltinRenderTextureType.CameraTarget, RenderTextureSubElement.Depth);
+            cmd.SetGlobalTexture(Fsr2Pipeline.SrvInputMotionVectors, BuiltinRenderTextureType.MotionVectors);
+            
+            SetupDispatchDescription(context);
+
+            if (settings.autoGenerateReactiveMask)
+            {
+                // TODO: auto-generate reactive mask
+            }
+            
+            cmd.GetTemporaryRT(Fsr2Pipeline.UavUpscaledOutput, DisplaySize.x, DisplaySize.y, 0, default, context.sourceFormat, default, 1, true);
+            
+            _fsrContext.Dispatch(_dispatchDescription, cmd);
+            
+            cmd.BlitFullscreenTriangle(Fsr2Pipeline.UavUpscaledOutput, context.destination);
+            cmd.ReleaseTemporaryRT(Fsr2Pipeline.UavUpscaledOutput);
         }
 
         /// <summary>
@@ -189,6 +208,45 @@ namespace FidelityFX
             camera.projectionMatrix = jitterTranslationMatrix * camera.nonJitteredProjectionMatrix;
             camera.useJitteredProjectionMatrixForTransparentRendering = true;
         }
+
+        private void SetupDispatchDescription(PostProcessRenderContext context)
+        {
+            var camera = context.camera;
+            
+            // Set up the main FSR2 dispatch parameters
+            // The input and output textures are left blank here, as they are already being bound elsewhere in this source file
+            _dispatchDescription.Color = null;
+            _dispatchDescription.Depth = null;
+            _dispatchDescription.MotionVectors = null;
+            _dispatchDescription.Exposure = null;
+            _dispatchDescription.Reactive = null;
+            _dispatchDescription.TransparencyAndComposition = null;
+            
+            if (!settings.enableAutoExposure && settings.exposure.value != null) _dispatchDescription.Exposure = settings.exposure.value;
+            if (settings.reactiveMask.value != null) _dispatchDescription.Reactive = settings.reactiveMask.value;
+            if (settings.transparencyAndCompositionMask.value != null) _dispatchDescription.TransparencyAndComposition = settings.transparencyAndCompositionMask.value;
+            
+            _dispatchDescription.Output = null;
+            _dispatchDescription.PreExposure = settings.preExposure;
+            _dispatchDescription.EnableSharpening = settings.performSharpenPass;
+            _dispatchDescription.Sharpness = settings.sharpness;
+            _dispatchDescription.MotionVectorScale.x = -camera.pixelWidth;
+            _dispatchDescription.MotionVectorScale.y = -camera.pixelHeight;
+            _dispatchDescription.RenderSize = RenderSize;
+            _dispatchDescription.InputResourceSize = new Vector2Int(context.width, context.height);
+            _dispatchDescription.FrameTimeDelta = Time.unscaledDeltaTime;
+            _dispatchDescription.CameraNear = camera.nearClipPlane;
+            _dispatchDescription.CameraFar = camera.farClipPlane;
+            _dispatchDescription.CameraFovAngleVertical = camera.fieldOfView * Mathf.Deg2Rad;
+            _dispatchDescription.ViewSpaceToMetersFactor = 1.0f; // 1 unit is 1 meter in Unity
+            _dispatchDescription.Reset = m_ResetHistory;
+            
+            if (SystemInfo.usesReversedZBuffer)
+            {
+                // Swap the near and far clip plane distances as FSR2 expects this when using inverted depth
+                (_dispatchDescription.CameraNear, _dispatchDescription.CameraFar) = (_dispatchDescription.CameraFar, _dispatchDescription.CameraNear);
+            }
+        }
     }
 
     internal class Fsr2PostProcessHelper : MonoBehaviour