Question Custom pass AggregateCullingParameters not working

I am using Unity 2021.2.4f1 and HDRP 12.1.1. I am trying to create custom pass for rendering metaballs.

This is my custom pass code:

Code (CSharp):

1. using UnityEngine;
2. using UnityEngine.Experimental.Rendering;
3. using UnityEngine.Rendering;
4. using UnityEngine.Rendering.HighDefinition;
5.  
6.  
7. public class LiquidPass : CustomPass
8. {
9.     [SerializeField] private Material blitMaterial;
10.     [SerializeField] private LayerMask layerMask = 0;
11.     [SerializeField] private int blurSampleCount = 25;
12.     [SerializeField] private int blurRadius = 40;
13.  
14.     private RTHandle blurBuffer;
15.  
16.     protected override void Setup(ScriptableRenderContext renderContext, CommandBuffer commandBuffer)
17.     {
18.         blurBuffer = RTHandles.Alloc(
19.             scaleFactor: new Vector2(0.5f, 0.5f),
20.             slices: TextureXR.slices,
21.             dimension: TextureXR.dimension,
22.             colorFormat: GraphicsFormat.R16G16B16A16_SNorm,
23.             useDynamicScale: true,
24.             name: "Blur Buffer"
25.         );
26.     }
27.  
28.     protected override void AggregateCullingParameters(ref ScriptableCullingParameters cullingParameters, HDCamera camera)
29.     {
30.         cullingParameters.cullingMask |= (uint)layerMask.value;
31.     }
32.  
33.     protected override void Execute(CustomPassContext customPassContext)
34.     {
35.         // Draw renderers with selected layers
36.         CustomPassUtils.DrawRenderers(customPassContext, layerMask);
37.  
38.         // Blur custom buffer
39.         RTHandle target = customPassContext.customColorBuffer.Value;
40.         float blurRadiusScale = customPassContext.cameraColorBuffer.rtHandleProperties.rtHandleScale.x;
41.         CustomPassUtils.GaussianBlur(customPassContext, target, target, blurBuffer, blurSampleCount, blurRadius * blurRadiusScale, downSample: true);
42.  
43.         // Blit custom buffer to camera buffer
44.         int passId = blitMaterial.FindPass("Forward");
45.         if (passId == -1) passId = blitMaterial.FindPass("ForwardOnly");
46.         CoreUtils.SetRenderTarget(customPassContext.cmd, customPassContext.cameraColorBuffer, customPassContext.cameraDepthBuffer);
47.         CoreUtils.DrawFullScreen(customPassContext.cmd, blitMaterial, shaderPassId: passId);
48.     }
49.  
50.     protected override void Cleanup()
51.     {
52.         blurBuffer.Release();
53.     }
54. }
55.  

It works as expected, but the original objects are still rendered by the camera:


When I disable Liquid layer in the camera Culling Mask, the objects completely disappear but
CustomPassUtils.DrawRenderers does not render them either.

If I remove AggregateCullingParameters override completely the camera renders them but DrawRenderers does not in any circumstances.

These are my custom pass settings:


I have other issue too where when I change TargetDepthBuffer to Custom, the DrawRenderers again does not render the objects in any way (stops working) which is weird.

What's more weird is that I am trying to achieve an effect similar to that in this example: https://github.com/alelievr/HDRP-Custom-Passes/tree/master/Assets/CustomPasses/Liquid , and in that example it works in the Visual Effect graph but does not work on the mesh renderers (left: scene view, right: game view):