[HDRP] Custom render pass SetGlobalTexture issue

[b1gry4n]

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.

 protected override void Setup(ScriptableRenderContext renderContext, CommandBuffer cmd)
    {
        shaderTags = new ShaderTagId[3]
        {
            new ShaderTagId("Forward"),
            new ShaderTagId("ForwardOnly"),
            new ShaderTagId("")
        };

        maskBuffer = RTHandles.Alloc(
            Vector2.one, TextureXR.slices, dimension: TextureXR.dimension,
            colorFormat: GraphicsFormat.R16G16B16A16_SFloat,
            useDynamicScale: true, enableRandomWrite: true,name: "_MaskBuffer"
        );

        maskDepthBuffer = RTHandles.Alloc(
                 Vector2.one, TextureXR.slices, dimension: TextureXR.dimension,
                 colorFormat: GraphicsFormat.R16_UInt, useDynamicScale: true,
                 name: "_MaskBufferDepth", depthBufferBits: DepthBits.Depth16
             );
    }


protected override void Execute(ScriptableRenderContext renderContext, CommandBuffer cmd, HDCamera hdCamera, CullingResults cullingResult)
    {
        if (staticMaterial == null || dynamicMaterial == null || (!drawStatic && !drawDynamic))
        {
            return;
        }

        //This is not working
        //*****
        cmd.SetGlobalTexture("_MaskBuffer", maskBuffer);
        //I have also tried:
        //cmd.SetGlobalTexture("_MaskBuffer", maskBuffer.nameID);
        //cmd.SetGlobalTexture("_MaskBuffer", maskBuffer.rt);
        //Shader.SetGlobalTexture("_MaskBuffer", maskBuffer);
        //Shader.SetGlobalTexture("_MaskBuffer", maskBuffer.rt);
        //*****

        CoreUtils.SetRenderTarget(cmd, maskBuffer, maskDepthBuffer, ClearFlag.All);     
        if (drawStatic)
        {
            Render(renderContext, cmd, hdCamera, cullingResult, staticMask, staticMaterial);
        }
        if (drawDynamic)
        {
            Render(renderContext, cmd, hdCamera, cullingResult, dynamicMask, dynamicMaterial);
        }
        SetCameraRenderTarget(cmd);
    }


void Render(ScriptableRenderContext renderContext, CommandBuffer cmd, HDCamera hdCamera, CullingResults cullingResult, LayerMask LayerMask, Material material)
    {
        var renstateBlock = new RenderStateBlock(RenderStateMask.Depth)
        {
            depthState = new DepthState(true, depthCompareFunction),
            stencilState = new StencilState(false),
        };

        var result = new RendererListDesc(shaderTags, cullingResult, hdCamera.camera)
        {
            rendererConfiguration = PerObjectData.None,
            renderQueueRange = GetRenderQueueRange(renderQueueType),
            sortingCriteria = Sorting,
            excludeObjectMotionVectors = false,
            overrideMaterial = material,
            overrideMaterialPassIndex = (material != null) ? material.FindPass(overrideMaterialPassName) : 0,
            stateBlock = renstateBlock,
            layerMask = LayerMask,
        };
     
        // Render objects into the custom buffer:
        HDUtils.DrawRendererList(renderContext, cmd, RendererList.Create(result));
    }

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.

[antoinel_unity]

Hello,

@b1gry4n

        maskBuffer = RTHandles.Alloc(
            Vector2.one, TextureXR.slices, dimension: TextureXR.dimension,
            colorFormat: GraphicsFormat.R16G16B16A16_SFloat,
            useDynamicScale: true, enableRandomWrite: true,name: "_MaskBuffer"
        );

when you allocate a texture with this function, Unity will allocate a Texture2DArray, because of the VR support (it’s the TextureXR.dimension in parameter). So when you do your SetGlobalTexture, you’re binding a Texture2DArray to a texture2D in your shader which doesn’t work. To fix the issue, you can declare a Texture2DArray in the shader instead of a Texture2D or allocate a Texture2D in the C# (in that case your effect won’t work with VR).