DrawIndirect: baseVertexLocation & startInstanceLocation broken on DX11/DX12. Vulkan works fine.

The bug has been confirmed by Unity, but will not be fixed for the time being.

According to the bug’s page, a feature request has been created to explore how this can be fixed in the future.
Please note that parts of this issue have been reported in 2017 already, so you should probably check if you can use another function or a workaround as it might probably take some time before this gets addressed.

We are using Graphics.RenderMeshIndirect now. Using it, baseVertexIndex and startInstance are now correctly passed to the shader when using DX11, DX12 and Vulkan. See this thread for a quick example.