Mesh triangles and shadowcaster values increase for Intermediate Renderers when 'Occlusion Culling' is used and 'Cast Shadows' is enabled on the Mesh

Reproduction steps:

1. Open attached IntermediateRendererOcclusionTest project
2. Open SampleScene
3. Open the window for Occlusion Culling/Baking and make sure that there is baked occlusion culling data
4. If not, enable "GameObject" in the Hierarchy window and bake
   • Once baking is done, disable "GameObject"
5. Ensure that "MeshDrawer" is enabled
6. Enter play mode and enable the stats overlay for the Game view
7. Enable and disable occlusion culling setting on the MainCamera while in play mode
   1. take note of the change in number of shadow casters and vertex counts
   2. enabling occlusion culling increases both counts
   3. disabling occlusion culling decreases both counts
8. Open frame debugger and enable it
9. step through the opaque shadows pass
10. Enable and disable occlusion culling again and observe the shadow pass each time
    • take note of the increase in draw events for when occlusion culling is enabled

Expected: Occlusion culling results in the same number of shadowcasters and vertex counts in the worst case and decreases both counts in the best case

Actual: Occlusion culling increases these counts and results in more rendering work for shadowcasters

 

Reproduction steps:
1. Open the attached “Grass_bug.zip” project
2. Open the SampleScene”
3. Enter the Play mode
4. In the Game view open the Stats Window
5. Observe the Tris value
6. Select the “Main Camera” GameObject from the Hierarchy
7. In the Inspector, disable Occlusion Culling
8. Observe the Tris value again

Expected result: The value does not change
Actual result: When “Occlusion Culling” is disabled the Tris value drops from “2.2mil” to “982k”

Reproducible with: 2023.3.0b5, 6000.0.36f1, 6000.1.0b4, 6000.2.0a1
Not reproducible with: 2022.3.57f1, 2023.3.0b4

Reproducible on: Windows 10 (User reported), Windows 11
Not reproducible on: No other environment tested

Note:

• Changing the ‘Cast Shadows’ property to ‘Off’ on the Assets/Scenes/Bug/Cube.prefab makes the issue also not reproduce