Compute and cull by triangle area early before writing 4-groups of tr…

…iangles

Common/Math/CrossSIMD.h

@@ -266,6 +266,10 @@ struct Vec4F32 {
 inline Vec4S32 Vec4S32FromF32(Vec4F32 f) { return Vec4S32{ _mm_cvttps_epi32(f.v) }; }
 inline Vec4F32 Vec4F32FromS32(Vec4S32 f) { return Vec4F32{ _mm_cvtepi32_ps(f.v) }; }
 
+inline bool AnyZeroSignBit(Vec4F32 value) {
+	return _mm_movemask_ps(value.v) != 0xF;
+}
+
 // Make sure the W component of scale is 1.0f.
 inline void ScaleInplace(Mat4F32 &m, Vec4F32 scale) {
 	m.col0 = _mm_mul_ps(m.col0, scale.v);
@@ -609,6 +613,14 @@ inline bool AnyZeroSignBit(Vec4S32 value) {
 	return (mask & 0x80000000) == 0;
 }
 
+inline bool AnyZeroSignBit(Vec4F32 value) {
+	int32x4_t ival = vreinterpretq_s32_f32(value.v);
+	int32x2_t prod = vand_s32(vget_low_s32(ival), vget_high_s32(ival));
+	int mask = vget_lane_s32(prod, 0) & vget_lane_s32(prod, 1);
+	return (mask & 0x80000000) == 0;
+}
+
+
 struct Vec4U16 {
 	uint16x4_t v;  // 64 bits.
 

GPU/Common/DepthRaster.cpp

@@ -99,8 +99,7 @@ struct Edge {
 enum class TriangleResult {
 	OK,
 	NoPixels,
-	Backface,
-	TooSmall,
+	SmallOrBackface,
 };
 
 constexpr int MIN_TWICE_TRI_AREA = 10;
@@ -130,16 +129,14 @@ TriangleResult DepthRasterTriangle(uint16_t *depthBuf, int stride, DepthScissor
 	int maxY = std::min(std::max(std::max(v0y, v1y), v2y), (int)scissor.y2);
 	if (maxX == minX || maxY == minY) {
 		// No pixels, or outside screen.
+		// Most of these are now gone in the initial pass.
 		return TriangleResult::NoPixels;
 	}
 
 	// TODO: Cull really small triangles here - we can increase the threshold a bit probably.
 	int triArea = (v1y - v2y) * v0x + (v2x - v1x) * v0y + (v1x * v2y - v2x * v1y);
-	if (triArea < 0) {
-		return TriangleResult::Backface;
-	}
 	if (triArea < MIN_TWICE_TRI_AREA) {
-		return TriangleResult::TooSmall;  // Or zero area.
+		return TriangleResult::SmallOrBackface;  // Or zero area.
 	}
 
 	float oneOverTriArea = 1.0f / (float)triArea;
@@ -420,6 +417,14 @@ int DepthRasterClipIndexedTriangles(int *tx, int *ty, float *tz, const float *tr
 			continue;
 		}
 
+		// Floating point triangle area. Can't be reused for the integer-snapped raster reliably (though may work...)
+		// Still good for culling early and pretty cheap to compute.
+		Vec4F32 triArea = (y1 - y2) * x0 + (x2 - x1) * y0 + (x1 * y2 - x2 * y1) - Vec4F32::Splat((float)MIN_TWICE_TRI_AREA);
+		if (!AnyZeroSignBit(triArea)) {
+			gpuStats.numDepthRasterEarlySize += 4;
+			continue;
+		}
+
 		Vec4S32FromF32(x0).Store(tx + outCount);
 		Vec4S32FromF32(x1).Store(tx + outCount + 4);
 		Vec4S32FromF32(x2).Store(tx + outCount + 8);
@@ -470,7 +475,7 @@ void DepthRasterScreenVerts(uint16_t *depth, int depthStride, const int *tx, con
 		break;
 	case GE_PRIM_TRIANGLES:
 	{
-		int stats[4]{};
+		int stats[3]{};
 		// Batches of 4 triangles, as output by the clip function.
 		for (int i = 0; i < count; i += 12) {
 			switch (draw.compareMode) {
@@ -491,9 +496,8 @@ void DepthRasterScreenVerts(uint16_t *depth, int depthStride, const int *tx, con
 			}
 			}
 		}
-		gpuStats.numDepthRasterBackface += stats[(int)TriangleResult::Backface];
 		gpuStats.numDepthRasterNoPixels += stats[(int)TriangleResult::NoPixels];
-		gpuStats.numDepthRasterTooSmall += stats[(int)TriangleResult::TooSmall];
+		gpuStats.numDepthRasterTooSmall += stats[(int)TriangleResult::SmallOrBackface];
 		gpuStats.numDepthRasterPrims += stats[(int)TriangleResult::OK];
 		break;
 	}

GPU/GPU.h

@@ -111,7 +111,7 @@ struct GPUStatistics {
 		msPrepareDepth = 0.0f;
 		msRasterizeDepth = 0.0f;
 		numDepthRasterPrims = 0;
-		numDepthRasterBackface = 0;
+		numDepthRasterEarlySize = 0;
 		numDepthRasterNoPixels = 0;
 		numDepthRasterTooSmall = 0;
 		numDepthRasterZCulled = 0;
@@ -160,7 +160,7 @@ struct GPUStatistics {
 	int vertexGPUCycles;
 	int otherGPUCycles;
 	int numDepthRasterPrims;
-	int numDepthRasterBackface;
+	int numDepthRasterEarlySize;
 	int numDepthRasterNoPixels;
 	int numDepthRasterTooSmall;
 	int numDepthRasterZCulled;

GPU/GPUCommonHW.cpp

@@ -1801,7 +1801,7 @@ size_t GPUCommonHW::FormatGPUStatsCommon(char *buffer, size_t size) {
 		"replacer: tracks %d references, %d unique textures\n"
 		"Cpy: depth %d, color %d, reint %d, blend %d, self %d\n"
 		"GPU cycles: %d (%0.1f per vertex)\n"
-		"Z-rast: %0.2f/%0.2f ms, %d prim, %d nopix, %d small, %d back, %d zcull, %d box\n%s",
+		"Z-rast: %0.2f/%0.2f ms, %d prim, %d nopix, %d small, %d earlysize, %d zcull, %d box\n%s",
 		gpuStats.msProcessingDisplayLists * 1000.0f,
 		gpuStats.numDrawSyncs,
 		gpuStats.numListSyncs,
@@ -1843,7 +1843,7 @@ size_t GPUCommonHW::FormatGPUStatsCommon(char *buffer, size_t size) {
 		gpuStats.numDepthRasterPrims,
 		gpuStats.numDepthRasterNoPixels,
 		gpuStats.numDepthRasterTooSmall,
-		gpuStats.numDepthRasterBackface,
+		gpuStats.numDepthRasterEarlySize,
 		gpuStats.numDepthRasterZCulled,
 		gpuStats.numDepthEarlyBoxCulled,
 		debugRecording_ ? "(debug-recording)" : ""