Bind gaussian splat chunk metadata in prepare pass

engine/assets/builtin/shaders/gaussian-splat-utilities.shader

@@ -20,6 +20,25 @@ Shader "Builtin Gaussian Splat Utilities"
         float coefficients[45];
     };
 
+    struct GaussianSplatChunkData
+    {
+        uint colR;
+        uint colG;
+        uint colB;
+        uint colA;
+        float2 posX;
+        float2 posY;
+        float2 posZ;
+        uint sclX;
+        uint sclY;
+        uint sclZ;
+        uint shR;
+        uint shG;
+        uint shB;
+    };
+
+    static const uint GAUSSIAN_SPLAT_CHUNK_SIZE = 256u;
+
     static const float SH_C1 = 0.4886025;
     static const float SH_C2[] = { 1.0925484, -1.0925484, 0.3153916, -1.0925484, 0.5462742 };
     static const float SH_C3[] = { -0.5900436, 2.8906114, -0.4570458, 0.3731763, -0.4570458, 1.4453057, -0.5900436 };
@@ -211,6 +230,7 @@ Shader "Builtin Gaussian Splat Utilities"
             StructuredBuffer<GaussianSplatOtherData> GaussianSplatOther;
             StructuredBuffer<float4> GaussianSplatColor;
             StructuredBuffer<GaussianSplatSHData> GaussianSplatSH;
+            StructuredBuffer<GaussianSplatChunkData> GaussianSplatChunks;
             RWStructuredBuffer<uint> GaussianSplatSortDistances;
             RWStructuredBuffer<uint> GaussianSplatOrderBuffer;
             RWStructuredBuffer<GaussianSplatViewData> GaussianSplatViewDataBuffer;
@@ -240,7 +260,16 @@ Shader "Builtin Gaussian Splat Utilities"
                 const GaussianSplatOtherData otherData = GaussianSplatOther[index];
                 const float4 colorOpacity = GaussianSplatColor[index];
                 const GaussianSplatSHData shData = GaussianSplatSH[index];
+                const GaussianSplatChunkData chunkData = GaussianSplatChunks[index / GAUSSIAN_SPLAT_CHUNK_SIZE];
                 const uint shOrder = min((uint)gSplatParams.z, 3u);
+                if (chunkData.posX.x > chunkData.posX.y ||
+                    chunkData.posY.x > chunkData.posY.y ||
+                    chunkData.posZ.x > chunkData.posZ.y)
+                {
+                    GaussianSplatSortDistances[index] = 0xffffffffu;
+                    GaussianSplatViewDataBuffer[index] = viewData;
+                    return;
+                }
 
                 const float3 worldCenter = mul(gModelMatrix, float4(localCenter, 1.0)).xyz;
                 const float3 viewCenter = mul(gViewMatrix, float4(worldCenter, 1.0)).xyz;