1 files changed, 115 insertions, 0 deletions
diff --git a/thirdparty/amd-fsr2/shaders/ffx_fsr2_lock.h b/thirdparty/amd-fsr2/shaders/ffx_fsr2_lock.h
new file mode 100644
index 0000000000..8347fa86bc
--- /dev/null
+++ b/thirdparty/amd-fsr2/shaders/ffx_fsr2_lock.h
@@ -0,0 +1,115 @@
+// This file is part of the FidelityFX SDK.
+//
+// Copyright (c) 2022-2023 Advanced Micro Devices, Inc. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+#ifndef FFX_FSR2_LOCK_H
+#define FFX_FSR2_LOCK_H
+
+void ClearResourcesForNextFrame(in FfxInt32x2 iPxHrPos)
+{
+    if (all(FFX_LESS_THAN(iPxHrPos, FfxInt32x2(RenderSize()))))
+    {
+#if FFX_FSR2_OPTION_INVERTED_DEPTH
+        const FfxUInt32 farZ = 0x0;
+#else
+        const FfxUInt32 farZ = 0x3f800000;
+#endif
+        SetReconstructedDepth(iPxHrPos, farZ);
+    }
+}
+
+FfxBoolean ComputeThinFeatureConfidence(FfxInt32x2 pos)
+{
+    const FfxInt32 RADIUS = 1;
+
+    FfxFloat32 fNucleus = LoadLockInputLuma(pos);
+
+    FfxFloat32 similar_threshold = 1.05f;
+    FfxFloat32 dissimilarLumaMin = FSR2_FLT_MAX;
+    FfxFloat32 dissimilarLumaMax = 0;
+
+    /*
+     0 1 2
+     3 4 5
+     6 7 8
+    */
+
+    #define SETBIT(x) (1U << x)
+
+    FfxUInt32 mask = SETBIT(4); //flag fNucleus as similar
+
+    const FfxUInt32 uNumRejectionMasks = 4;
+    const FfxUInt32 uRejectionMasks[uNumRejectionMasks] = {
+        SETBIT(0) | SETBIT(1) | SETBIT(3) | SETBIT(4), //Upper left
+        SETBIT(1) | SETBIT(2) | SETBIT(4) | SETBIT(5), //Upper right
+        SETBIT(3) | SETBIT(4) | SETBIT(6) | SETBIT(7), //Lower left
+        SETBIT(4) | SETBIT(5) | SETBIT(7) | SETBIT(8), //Lower right
+    };
+
+    FfxInt32 idx = 0;
+    FFX_UNROLL
+    for (FfxInt32 y = -RADIUS; y <= RADIUS; y++) {
+        FFX_UNROLL
+        for (FfxInt32 x = -RADIUS; x <= RADIUS; x++, idx++) {
+            if (x == 0 && y == 0) continue;
+
+            FfxInt32x2 samplePos = ClampLoad(pos, FfxInt32x2(x, y), FfxInt32x2(RenderSize()));
+
+            FfxFloat32 sampleLuma = LoadLockInputLuma(samplePos);
+            FfxFloat32 difference = ffxMax(sampleLuma, fNucleus) / ffxMin(sampleLuma, fNucleus);
+
+            if (difference > 0 && (difference < similar_threshold)) {
+                mask |= SETBIT(idx);
+            } else {
+                dissimilarLumaMin = ffxMin(dissimilarLumaMin, sampleLuma);
+                dissimilarLumaMax = ffxMax(dissimilarLumaMax, sampleLuma);
+            }
+        }
+    }
+
+    FfxBoolean isRidge = fNucleus > dissimilarLumaMax || fNucleus < dissimilarLumaMin;
+
+    if (FFX_FALSE == isRidge) {
+
+        return false;
+    }
+
+    FFX_UNROLL
+    for (FfxInt32 i = 0; i < 4; i++) {
+
+        if ((mask & uRejectionMasks[i]) == uRejectionMasks[i]) {
+            return false;
+        }
+    }
+    
+    return true;
+}
+
+void ComputeLock(FfxInt32x2 iPxLrPos)
+{
+    if (ComputeThinFeatureConfidence(iPxLrPos))
+    {
+        StoreNewLocks(ComputeHrPosFromLrPos(iPxLrPos), 1.f);
+    }
+
+    ClearResourcesForNextFrame(iPxLrPos);
+}
+
+#endif // FFX_FSR2_LOCK_H