The answer is simply - there is TopLeft_Corner parameter - it’s physical volume location, so, it’s set to non zero world location in the VolumeTexture2Sample_inst and that’s the reason you cannot see anything in the cascade
The answer is simply - there is TopLeft_Corner parameter - it’s physical volume location, so, it’s set to non zero world location in the VolumeTexture2Sample_inst and that’s the reason you cannot see anything in the cascade