From 96f77282276163b6390b12e85abe701d11676ef5 Mon Sep 17 00:00:00 2001
From: Kelsi <kelsihates2fa@gmail.com>
Date: Sun, 8 Mar 2026 20:27:39 -0700
Subject: [PATCH] Add AMD FSR2 CI build job and adjust jitter offset sign

---
 .github/workflows/build.yml | 103 ++++++++++++++++++++++++++++++++++++
 src/rendering/renderer.cpp  |   6 ++-
 2 files changed, 107 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b903a442..e4c2fb53 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -73,6 +73,109 @@ jobs:
           path: build/wowee-*.deb
           if-no-files-found: error
 
+  build-linux-amd-fsr2:
+    name: Build (linux-amd-fsr2)
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          submodules: true
+
+      - name: Install dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y \
+            cmake \
+            build-essential \
+            pkg-config \
+            libsdl2-dev \
+            libglew-dev \
+            libglm-dev \
+            libssl-dev \
+            zlib1g-dev \
+            libvulkan-dev \
+            vulkan-tools \
+            glslc \
+            libavformat-dev \
+            libavcodec-dev \
+            libswscale-dev \
+            libavutil-dev \
+            libunicorn-dev \
+            libx11-dev \
+            wine64
+          sudo apt-get install -y libstorm-dev || true
+
+      - name: Fetch AMD FSR2 SDK
+        run: |
+          rm -rf extern/FidelityFX-FSR2
+          git clone --depth 1 https://github.com/GPUOpen-Effects/FidelityFX-FSR2.git extern/FidelityFX-FSR2
+
+      - name: Generate AMD FSR2 Vulkan permutation headers
+        run: |
+          set -euo pipefail
+          SDK_DIR="$PWD/extern/FidelityFX-FSR2"
+          SHADER_DIR="$SDK_DIR/src/ffx-fsr2-api/shaders"
+          OUT_DIR="$SDK_DIR/src/ffx-fsr2-api/vk/shaders"
+          SC="$SDK_DIR/tools/sc/FidelityFX_SC.exe"
+
+          BASE_ARGS=(
+            -reflection
+            -deps=gcc
+            -DFFX_GPU=1
+            -DFFX_FSR2_OPTION_UPSAMPLE_SAMPLERS_USE_DATA_HALF=0
+            -DFFX_FSR2_OPTION_ACCUMULATE_SAMPLERS_USE_DATA_HALF=0
+            -DFFX_FSR2_OPTION_REPROJECT_SAMPLERS_USE_DATA_HALF=1
+            -DFFX_FSR2_OPTION_POSTPROCESSLOCKSTATUS_SAMPLERS_USE_DATA_HALF=0
+            -DFFX_FSR2_OPTION_UPSAMPLE_USE_LANCZOS_TYPE=2
+            -compiler=glslang
+            -e
+            main
+            --target-env
+            vulkan1.1
+            -S
+            comp
+            -Os
+            -DFFX_GLSL=1
+            -DFFX_FSR2_OPTION_REPROJECT_USE_LANCZOS_TYPE={0,1}
+            -DFFX_FSR2_OPTION_HDR_COLOR_INPUT={0,1}
+            -DFFX_FSR2_OPTION_LOW_RESOLUTION_MOTION_VECTORS={0,1}
+            -DFFX_FSR2_OPTION_JITTERED_MOTION_VECTORS={0,1}
+            -DFFX_FSR2_OPTION_INVERTED_DEPTH={0,1}
+            -DFFX_FSR2_OPTION_APPLY_SHARPENING={0,1}
+          )
+
+          PASSES=(
+            ffx_fsr2_tcr_autogen_pass
+            ffx_fsr2_autogen_reactive_pass
+            ffx_fsr2_accumulate_pass
+            ffx_fsr2_compute_luminance_pyramid_pass
+            ffx_fsr2_depth_clip_pass
+            ffx_fsr2_lock_pass
+            ffx_fsr2_reconstruct_previous_depth_pass
+            ffx_fsr2_rcas_pass
+          )
+
+          for pass in "${PASSES[@]}"; do
+            HALF_ARG="-DFFX_HALF={0,1}"
+            if [ "$pass" = "ffx_fsr2_compute_luminance_pyramid_pass" ]; then
+              HALF_ARG="-DFFX_HALF=0"
+            fi
+            wine "$SC" "${BASE_ARGS[@]}" "$HALF_ARG" \
+              "-name=${pass}" \
+              "-I${SHADER_DIR}" \
+              "-output=${OUT_DIR}" \
+              "${SHADER_DIR}/${pass}.glsl"
+          done
+
+          test -f "$OUT_DIR/ffx_fsr2_accumulate_pass_permutations.h"
+
+      - name: Configure (AMD ON)
+        run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Release -DWOWEE_ENABLE_AMD_FSR2=ON
+
+      - name: Build
+        run: cmake --build build --parallel $(nproc)
+
   build-macos:
     name: Build (macOS ${{ matrix.arch }})
     runs-on: ${{ matrix.runner }}
diff --git a/src/rendering/renderer.cpp b/src/rendering/renderer.cpp
index ecec244e..bd22c400 100644
--- a/src/rendering/renderer.cpp
+++ b/src/rendering/renderer.cpp
@@ -4323,9 +4323,11 @@ void Renderer::dispatchAmdFsr2() {
         L"FSR2_Output", FFX_RESOURCE_STATE_UNORDERED_ACCESS);
 
     // Camera jitter is stored as NDC projection offsets; convert to render-pixel offsets.
+    // AMD jitter convention is opposite our projection offset sign in Vulkan space.
+    const float jitterSign = static_cast<float>(envIntOrDefault("WOWEE_FSR2_JITTER_SIGN", -1));
     glm::vec2 jitterNdc = camera->getJitter();
-    desc.jitterOffset.x = jitterNdc.x * 0.5f * static_cast<float>(fsr2_.internalWidth);
-    desc.jitterOffset.y = jitterNdc.y * 0.5f * static_cast<float>(fsr2_.internalHeight);
+    desc.jitterOffset.x = jitterSign * jitterNdc.x * 0.5f * static_cast<float>(fsr2_.internalWidth);
+    desc.jitterOffset.y = jitterSign * jitterNdc.y * 0.5f * static_cast<float>(fsr2_.internalHeight);
     desc.motionVectorScale.x = static_cast<float>(fsr2_.internalWidth);
     desc.motionVectorScale.y = static_cast<float>(fsr2_.internalHeight);
     desc.renderSize.width = fsr2_.internalWidth;