Houdini grid overlapping render output

[dedoardo]

The world grid overlay in Houdini overlaps the rendering output. I would guess the depth buffer needs to accessible to Houdini to correctly compose the two images.
There also seems to be some weird transparency going on, unsure if it's caused by the grid overlay though.

Would be nice to fix, though not an high priority.

[boberfly]

Yeah the depth AOV needs added, and I think this will help camera movement also as it's not working right either. I'd like to move the priority up but we can get by with GL mode as a workaround...

[dedoardo]

After PR #162, this has become only a Linux specific issue. Tested with Houdini libraries on different versions.