Hi,

I attached a shadow matte shader to a ground plane to collect an environment light's occlusions. When the environment light's rendering mode is set to “Direct Lighting”, shadow matte picks up the occlusions great. When I set rendering mode to “Ambient Occlusion”, the occlusions do not show up in the shadow matte shader (though the occlusions show up fine with a mantra surface shader).

Any ideas what might cause this or how to fix it? I'm attaching an example file. I figure it's best to use ambient occlusion for render time efficiency over direct lighting. I'm in Houdini 13, Windows 7.

Thanks,
Seth

Hmmm, it's working for me. Tried it under OS X (Houdini 13.0.198.21) and Ubuntu (13.0.231), and in both cases, I see the results in the first attached image. The AO mode is much noiser, but it's definitely AO.

Either it's a Windows-only issue, or an issue in your particular build of H13, perhaps? Which Houdini builds are you on?

One idea for a work-around: in your ROP, if you add the grid object as a Phantom Object (see second attachment). Does that do the same object?

Hi goldleaf thanks for the reply. Can you check the occlusion on the shadow matted grid object as well (in the alpha channel) to see if it shows up there?