Removed useless kernels

ScriptableRenderPipeline/HDRenderPipeline/HDRP/RenderPipelineResources/BufferPyramid.cs

         List<RTHandle> m_DepthPyramidMips = new List<RTHandle>();
         int[] m_DepthKernels = null;
         int depthKernel8 { get { return m_DepthKernels[0]; } }
+        int depthKernel1 { get { return m_DepthKernels[1]; } }
 
         public RTHandle colorPyramid { get { return m_ColorPyramidBuffer; } }
         public RTHandle depthPyramid { get { return m_DepthPyramidBuffer; } }
             m_DepthKernels = new int[]
             {
                 m_DepthPyramidCS.FindKernel("KDepthDownSample8"),
-                m_DepthPyramidCS.FindKernel("KDepthDownSample2_0"),
-                m_DepthPyramidCS.FindKernel("KDepthDownSample2_1"),
-                m_DepthPyramidCS.FindKernel("KDepthDownSample2_2"),
-                m_DepthPyramidCS.FindKernel("KDepthDownSample2_3"),
+                m_DepthPyramidCS.FindKernel("KDepthDownSample1")
-        int GetDepthKernel2(int pattern)
-        {
-            return m_DepthKernels[pattern + 1];
-        }
-
         float GetXRscale()
         {
             // for stereo double-wide, each half of the texture will represent a single eye's pyramid
         public void CreateBuffers()
         {
             m_ColorPyramidBuffer = RTHandle.Alloc(size => CalculatePyramidSize(size), filterMode: FilterMode.Trilinear, colorFormat: RenderTextureFormat.ARGBHalf, sRGB: false, useMipMap: true, autoGenerateMips: false, name: "ColorPymarid");
-            m_DepthPyramidBuffer = RTHandle.Alloc(size => CalculatePyramidSize(size), filterMode: FilterMode.Trilinear, colorFormat: RenderTextureFormat.RFloat, sRGB: false, useMipMap: true, autoGenerateMips: false, enableRandomWrite: true, name: "DepthPyramid"); // Need randomReadWrite because we downsample the first mip with a compute shader.
+            m_DepthPyramidBuffer = RTHandle.Alloc(size => CalculatePyramidSize(size), filterMode: FilterMode.Trilinear, colorFormat: RenderTextureFormat.RGFloat, sRGB: false, useMipMap: true, autoGenerateMips: false, enableRandomWrite: true, name: "DepthPyramid"); // Need randomReadWrite because we downsample the first mip with a compute shader.
         }
 
         public void DestroyBuffers()
                 var srcMip = new RectInt(0, 0, hdCamera.actualWidth >> i, hdCamera.actualHeight >> i);
                 var dstMip = new RectInt(0, 0, srcMip.width >> 1, srcMip.height >> 1);
 
-                var kernel = GetDepthKernel2(0);
+                var kernel = depthKernel1;
                 var kernelSize = 1;
                 var srcWorkMip = srcMip;
                 var dstWorkMip = dstMip;

ScriptableRenderPipeline/HDRenderPipeline/HDRP/RenderPipelineResources/DepthPyramid.compute

 // Algorithm
 // ------------------------------------------------
 // Downsample a depth texture by taking min value of sampled pixels
-// It also handles computing in a viewport of a texture.
-// When we use partial kernels there are only 4 patterns (first is full): 
-//  0.  |x|x|       1.  |x|o|       2.  |o|o|       3.  |o|o|
-//      |x|x|           |x|o|           |x|x|           |x|o|
-#pragma kernel KDepthDownSample8                    KERNEL_SIZE=8       PATTERN=0       KERNEL_NAME=KDepthDownSample8    
-#pragma kernel KDepthDownSample2_0                  KERNEL_SIZE=1       PATTERN=0       KERNEL_NAME=KDepthDownSample2_0
-#pragma kernel KDepthDownSample2_1                  KERNEL_SIZE=1       PATTERN=1       KERNEL_NAME=KDepthDownSample2_1
-#pragma kernel KDepthDownSample2_2                  KERNEL_SIZE=1       PATTERN=2       KERNEL_NAME=KDepthDownSample2_2
-#pragma kernel KDepthDownSample2_3                  KERNEL_SIZE=1       PATTERN=3       KERNEL_NAME=KDepthDownSample2_3
+#pragma kernel KDepthDownSample8                  KERNEL_SIZE=8       KERNEL_NAME=KDepthDownSample8    
+#pragma kernel KDepthDownSample1                  KERNEL_SIZE=1       KERNEL_NAME=KDepthDownSample1
 
 #pragma only_renderers d3d11 ps4 xboxone vulkan metal
 
 #endif
 
     // Select the nearest sample
-#if PATTERN == 0
-#elif PATTERN == 1
-    float minDepth = MIN_DEPTH(depths.x, depths.z);
-    float maxDepth = MAX_DEPTH(depths.x, depths.z);
-#elif PATTERN == 2
-    float minDepth = MIN_DEPTH(depths.x, depths.y);
-    float maxDepth = MAX_DEPTH(depths.x, depths.y);
-#elif PATTERN == 3
-    float minDepth = depths.x;
-    float maxDepth = depths.x;
-#endif
 
     // Write to the final target
     uint2 dstPixel = (_RectOffset >> 1) + dispatchThreadId;