Merge pull request #894 from Unity-Technologies/Fix-display-of-depth-pyramid

HDRenderPipeline: Fix display of debug pyramid

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Debug/DebugFullScreen.shader

             #include "../Debug/DebugDisplay.cs.hlsl"
 
             TEXTURE2D(_DebugFullScreenTexture);
-            SAMPLER(sampler_DebugFullScreenTexture);
             float _FullScreenDebugMode;
             float _RequireToFlipInputTexture;
 
 
             float2 SampleMotionVectors(float2 coords)
             {
-                return SAMPLE_TEXTURE2D(_DebugFullScreenTexture, sampler_DebugFullScreenTexture, coords).xy;
+                return SAMPLE_TEXTURE2D(_DebugFullScreenTexture, s_point_clamp_sampler, coords).xy;
             }
             // end motion vector utilties
 
                 // SSAO
                 if (_FullScreenDebugMode == FULLSCREENDEBUGMODE_SSAO)
                 {
-                    return 1.0f - SAMPLE_TEXTURE2D(_DebugFullScreenTexture, sampler_DebugFullScreenTexture, input.texcoord).xxxx;
+                    return 1.0f - SAMPLE_TEXTURE2D(_DebugFullScreenTexture, s_point_clamp_sampler, input.texcoord).xxxx;
-                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, sampler_DebugFullScreenTexture, input.texcoord);
-                    
+                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, s_point_clamp_sampler, input.texcoord);
+
                     if (AnyIsNan(color) || any(isinf(color)))
                     {
                         color = float4(1.0, 0.0, 0.0, 1.0);
                 }
                 if (_FullScreenDebugMode == FULLSCREENDEBUGMODE_DEFERRED_SHADOWS)
                 {
-                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, sampler_DebugFullScreenTexture, input.texcoord);
+                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, s_point_clamp_sampler, input.texcoord);
-                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, sampler_DebugFullScreenTexture, input.texcoord);
+                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, s_point_clamp_sampler, input.texcoord);
-                    float4 color = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, sampler_DebugFullScreenTexture, input.texcoord);
-                    return float4(color.rrr / (color.rrr + 1), 1.0);
+                    // Reuse depth display function from DebugViewMaterial
+                    float depth = SAMPLE_TEXTURE2D(_DebugFullScreenTexture, s_point_clamp_sampler, input.texcoord).r;
+                    PositionInputs posInput = GetPositionInput(input.positionCS.xy, _ScreenSize.zw, depth, UNITY_MATRIX_I_VP, UNITY_MATRIX_VP);
+                    float linearDepth = frac(posInput.linearDepth * 0.1);
+                    return float4(linearDepth.xxx, 1.0);
                 }
 
                 return float4(0.0, 0.0, 0.0, 0.0);

ScriptableRenderPipeline/HDRenderPipeline/HDRP/RenderPipelineResources/DepthPyramid.compute

 
     // Select the nearest sample
 #if UNITY_REVERSED_Z
-    float minDepth = max(min(depths.x, depths.y), max(depths.z, depths.w));
+    float minDepth = max(max(depths.x, depths.y), max(depths.z, depths.w));
 #else
     float minDepth = min(min(depths.x, depths.y), min(depths.z, depths.w));
 #endif