[HDRP] Custom render pass SetGlobalTexture issue

I am trying to render a buffer mask using a custom render pass and set a global shader texture to use this texture. I have been able to achieve the masking I want, but when I try to pass the texture to the shaders it doesnt seem to be showing up. Im not sure what i am doing wrong. I was able to achieve this in URP with a custom pass almost identical to the setup here minus the obvious differences in creating a custom pass between URP and HDRP. The only real difference I can see is I was using a temporary render texture in URP with GetTemporaryRT

Here is the meat of my custom render pass.

Code (CSharp):

1.  protected override void Setup(ScriptableRenderContext renderContext, CommandBuffer cmd)
2.     {
3.         shaderTags = new ShaderTagId[3]
4.         {
5.             new ShaderTagId("Forward"),
6.             new ShaderTagId("ForwardOnly"),
7.             new ShaderTagId("")
8.         };
9.  
10.         maskBuffer = RTHandles.Alloc(
11.             Vector2.one, TextureXR.slices, dimension: TextureXR.dimension,
12.             colorFormat: GraphicsFormat.R16G16B16A16_SFloat,
13.             useDynamicScale: true, enableRandomWrite: true,name: "_MaskBuffer"
14.         );
15.  
16.         maskDepthBuffer = RTHandles.Alloc(
17.                  Vector2.one, TextureXR.slices, dimension: TextureXR.dimension,
18.                  colorFormat: GraphicsFormat.R16_UInt, useDynamicScale: true,
19.                  name: "_MaskBufferDepth", depthBufferBits: DepthBits.Depth16
20.              );
21.     }
22.  
23.  
24. protected override void Execute(ScriptableRenderContext renderContext, CommandBuffer cmd, HDCamera hdCamera, CullingResults cullingResult)
25.     {
26.         if (staticMaterial == null || dynamicMaterial == null || (!drawStatic && !drawDynamic))
27.         {
28.             return;
29.         }
30.  
31.         //This is not working
32.         //*****
33.         cmd.SetGlobalTexture("_MaskBuffer", maskBuffer);
34.         //I have also tried:
35.         //cmd.SetGlobalTexture("_MaskBuffer", maskBuffer.nameID);
36.         //cmd.SetGlobalTexture("_MaskBuffer", maskBuffer.rt);
37.         //Shader.SetGlobalTexture("_MaskBuffer", maskBuffer);
38.         //Shader.SetGlobalTexture("_MaskBuffer", maskBuffer.rt);
39.         //*****
40.  
41.         CoreUtils.SetRenderTarget(cmd, maskBuffer, maskDepthBuffer, ClearFlag.All);  
42.         if (drawStatic)
43.         {
44.             Render(renderContext, cmd, hdCamera, cullingResult, staticMask, staticMaterial);
45.         }
46.         if (drawDynamic)
47.         {
48.             Render(renderContext, cmd, hdCamera, cullingResult, dynamicMask, dynamicMaterial);
49.         }
50.         SetCameraRenderTarget(cmd);
51.     }
52.  
53.  
54. void Render(ScriptableRenderContext renderContext, CommandBuffer cmd, HDCamera hdCamera, CullingResults cullingResult, LayerMask LayerMask, Material material)
55.     {
56.         var renstateBlock = new RenderStateBlock(RenderStateMask.Depth)
57.         {
58.             depthState = new DepthState(true, depthCompareFunction),
59.             stencilState = new StencilState(false),
60.         };
61.  
62.         var result = new RendererListDesc(shaderTags, cullingResult, hdCamera.camera)
63.         {
64.             rendererConfiguration = PerObjectData.None,
65.             renderQueueRange = GetRenderQueueRange(renderQueueType),
66.             sortingCriteria = Sorting,
67.             excludeObjectMotionVectors = false,
68.             overrideMaterial = material,
69.             overrideMaterialPassIndex = (material != null) ? material.FindPass(overrideMaterialPassName) : 0,
70.             stateBlock = renstateBlock,
71.             layerMask = LayerMask,
72.         };
73.    
74.         // Render objects into the custom buffer:
75.         HDUtils.DrawRendererList(renderContext, cmd, RendererList.Create(result));
76.     }

Here is the result of this pass I would like to set as a global texture as seen via frame debugger



Here is the shader and the custom function I am using to retrieve the texture.



The expected result is for the render texture to appear on the cube, but as you can see it isnt. Im not sure what I am doing wrong.

 

SAMPLE_TEXTURE2D only works with Texture2D, so what you're shader is sampling is the default 16x16 gray texture.

Use this instead:

Code (CSharp):

1. //Declaration
2. TEXTURE2D_X(_MaskBuffer)
3. //Sampling
4. SAMPLE_TEXTURE2D_X(_MaskBuffer, sampler_MaskBuffer, uv)

RenderTargets are in a texture array, because of stereo pass instanced support. So this macro has to be used, the rest is handled under the hood.

 

Thanks, changing the hlsl in the custom node to the following solved the issue.

Code (CSharp):

1. #include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/TextureXR.hlsl"
2. TEXTURE2D_X(_MaskBuffer);
3. SAMPLER(sampler_MaskBuffer);
4.  
5. void ObjectMask_float(float2 In, out float4 Out)
6. {
7.     float4 samp = SAMPLE_TEXTURE2D_X(_MaskBuffer, sampler_MaskBuffer, In);
8.     Out = samp;
9. }