Vray 1.5 SP1 - Matte Object Issues

[Druski]

Howdy,

Since upgrading to Vray 1.5 SP1 I am having major issues with matte objects/materials. Any ideas what might be causing this, I have been banging my head against a brick wall for days now with no no success. The only difference between the two renders below is is in the the 2nd image, where the stone walls are set to matte object. I end up with wierd white artifacts on the stone surfaces, and the sphere gets considerably brighter.

[vlado]

It is hard to say what is going without a scene to debug; if you wish, you can email me one to vlado@chaosgroup.com so that I can take a look at what may be wrong.

Best regards,
Vlado

[Druski]

vlado,

Any progress on this, I sent you the scene via email, let me know if you haven't recieved it.

Drew

[vlado]

Yes, I received it; was a bit swamped with other issues, but I will check it out later tonight.

Best regards,
Vlado

[vlado]

So if you uncheck the "No GI on other mattes" option for the matte object, all will be fine.

When this option is ON, the matte geometry will be ignored for GI rays from other matte objects (including itself), and since in your case a large portion of the envrionment is blocked by the matte object itself, this changes its brightness. When this option is OFF, the matte object blocks GI as it normally does so all is fine.

Best regards,
Vlado

[Druski]

Yes, that fixes the way the object renders, however it makes the alpha unusable.

[vlado]

Hm, looks correct to me (at least, this is what the alpha is supposed to look like in this case); can you explain a little bit what you are trying to do as a final result?

Best regards,
Vlado