Full-on packetized SSE CalcInsideFrustum

SoftwareOcclusionCulling/AABBoxRasterizerSSE.cpp

@@ -17,6 +17,22 @@
 
 #include "AABBoxRasterizerSSE.h"
 
+struct AABBoxRasterizerSSE::WorldBBoxPacket
+{
+	__m128 mCenter[3];
+	__m128 mHalf[3];
+
+	inline void SetLane(UINT lane, const float3& center, const float3& half)
+	{
+		mCenter[0].m128_f32[lane] = center.x;
+		mCenter[1].m128_f32[lane] = center.y;
+		mCenter[2].m128_f32[lane] = center.z;
+		mHalf[0].m128_f32[lane] = half.x;
+		mHalf[1].m128_f32[lane] = half.y;
+		mHalf[2].m128_f32[lane] = half.z;
+	}
+};
+
 AABBoxRasterizerSSE::AABBoxRasterizerSSE()
 	: mNumModels(0),
 	  mpTransformedAABBox(NULL),
@@ -44,9 +60,9 @@ AABBoxRasterizerSSE::~AABBoxRasterizerSSE()
 {
 	_aligned_free(mViewMatrix);
 	_aligned_free(mProjMatrix);
+	_aligned_free(mpWorldBoxes);
 	SAFE_DELETE_ARRAY(mpVisible);
 	SAFE_DELETE_ARRAY(mpTransformedAABBox);
-	SAFE_DELETE_ARRAY(mpWorldBoxes);
 	SAFE_DELETE_ARRAY(mpBBoxVisible);
 	SAFE_DELETE_ARRAY(mpNumTriangles);
 }
@@ -76,9 +92,12 @@ void AABBoxRasterizerSSE::CreateTransformedAABBoxes(CPUTAssetSet **pAssetSet, UI
 
 	mpVisible = new bool[mNumModels];
 	mpTransformedAABBox = new TransformedAABBoxSSE[mNumModels];
-	mpWorldBoxes = new WorldBBox[mNumModels];
 	mpBBoxVisible = new bool[mNumModels];
 	mpNumTriangles = new UINT[mNumModels];
+
+	UINT numPackets = (mNumModels + 3) / 4;
+	mpWorldBoxes = (WorldBBoxPacket *) _aligned_malloc(numPackets * sizeof(WorldBBoxPacket), 16);
+	memset(mpWorldBoxes, 0, numPackets * sizeof(WorldBBoxPacket));
 
 	for(UINT assetId = 0, modelId = 0; assetId < numAssetSets; assetId++)
 	{
@@ -93,7 +112,11 @@ void AABBoxRasterizerSSE::CreateTransformedAABBoxes(CPUTAssetSet **pAssetSet, UI
 				pModel = (CPUTModelDX11*)pRenderNode;
 
 				mpTransformedAABBox[modelId].CreateAABBVertexIndexList(pModel);
-				pModel->GetBoundsWorldSpace(&mpWorldBoxes[modelId].mCenter, &mpWorldBoxes[modelId].mHalf);
+
+				float3 bbCenter, bbHalf;
+				pModel->GetBoundsWorldSpace(&bbCenter, &bbHalf);
+				mpWorldBoxes[modelId / 4].SetLane(modelId & 3, bbCenter, bbHalf);
+
 				mpNumTriangles[modelId] = 0;
 				for(int meshId = 0; meshId < pModel->GetMeshCount(); meshId++)
 				{
@@ -192,8 +215,62 @@ void AABBoxRasterizerSSE::Render(CPUTAssetSet **pAssetSet,
 //------------------------------------------------------------------------
 void AABBoxRasterizerSSE::CalcInsideFrustum(CPUTFrustum *pFrustum, UINT start, UINT end)
 {
-	for(UINT i = start; i < end; i++)
+	// Packet start/end (rounding up)
+	UINT packetStart = (start + 3) / 4;
+	UINT packetEnd = (end + 3) / 4;
+
+	// Prepare plane equations
+	__m128 planeNormal[6][3];
+	__m128 planeNormalSign[6][3];
+	__m128 planeDist[6];
+	__m128 signMask = _mm_castsi128_ps(_mm_set1_epi32(0x80000000));
+	for(UINT i = 0; i < 6; i++)
+	{
+		for (UINT j = 0; j < 3; j++)
+		{
+			planeNormal[i][j] = _mm_set1_ps(pFrustum->mpNormal[i].f[j]);
+			planeNormalSign[i][j] = _mm_and_ps(planeNormal[i][j], signMask);
+		}
+
+		planeDist[i] = _mm_set1_ps(pFrustum->mPlanes[3*8 + i]);
+	}
+
+	// Loop over packets
+	bool * __restrict visible = mpBBoxVisible;
+	for(UINT i = packetStart; i < packetEnd; i++)
 	{
-		mpBBoxVisible[i] = pFrustum->IsVisible(mpWorldBoxes[i].mCenter, mpWorldBoxes[i].mHalf);
+		// Start assuming all 4 boxes are inside
+		__m128 inMask = _mm_castsi128_ps(_mm_set1_epi32(~0));
+
+		// Loop over planes
+		for (UINT j = 0; j < 6; j++)
+		{
+			// Sign for half[XYZ] so that dot product with plane normal would be maximal
+			__m128 halfSignX = _mm_xor_ps(mpWorldBoxes[i].mHalf[0], planeNormalSign[j][0]);
+			__m128 halfSignY = _mm_xor_ps(mpWorldBoxes[i].mHalf[1], planeNormalSign[j][1]);
+			__m128 halfSignZ = _mm_xor_ps(mpWorldBoxes[i].mHalf[2], planeNormalSign[j][2]);
+
+			// Bounding box corner to test (min corner)
+			__m128 cornerX = _mm_sub_ps(mpWorldBoxes[i].mCenter[0], halfSignX);
+			__m128 cornerY = _mm_sub_ps(mpWorldBoxes[i].mCenter[1], halfSignY);
+			__m128 cornerZ = _mm_sub_ps(mpWorldBoxes[i].mCenter[2], halfSignZ);
+
+			// Compute dot product
+			__m128 dot = planeDist[j];
+			dot = _mm_add_ps(dot, _mm_mul_ps(cornerX, planeNormal[j][0]));
+			dot = _mm_add_ps(dot, _mm_mul_ps(cornerY, planeNormal[j][1]));
+			dot = _mm_add_ps(dot, _mm_mul_ps(cornerZ, planeNormal[j][2]));
+
+			// The plane box is inside as long as the dot product is negative -> sign bit set
+			// So AND result together with current mask
+			inMask = _mm_and_ps(inMask, dot);
+		}
+
+		// Write the results for this packet
+		int packetMask = _mm_movemask_ps(inMask);
+		visible[i*4 + 0] = (packetMask >> 0) & 1;
+		visible[i*4 + 1] = (packetMask >> 1) & 1;
+		visible[i*4 + 2] = (packetMask >> 2) & 1;
+		visible[i*4 + 3] = (packetMask >> 3) & 1;
 	}
 }

SoftwareOcclusionCulling/AABBoxRasterizerSSE.h

@@ -89,15 +89,11 @@ class AABBoxRasterizerSSE : public AABBoxRasterizer
 
 
 	protected:
-		struct WorldBBox
-		{
-			float3 mCenter;
-			float3 mHalf;
-		};
+		struct WorldBBoxPacket;
 
 		UINT mNumModels;
 		TransformedAABBoxSSE *mpTransformedAABBox;
-		WorldBBox *mpWorldBoxes;
+		WorldBBoxPacket *mpWorldBoxes;
 		bool *mpBBoxVisible;
 		UINT *mpNumTriangles;
 		__m128 *mViewMatrix;