material with additive setting

[Guest]

Hi
Is there a V-Ray equivalent to "Additive" in the "Extended Parameters" in a Standard max material?

[hermit.crab]

There aren't such transparency controls in the V-Ray materials. On a simple scene, with an object in front of a plane textured with a Screen mapped checker texture (copied with reverse colors for the object), I managed to reproduce the "Additive" behavior. However, for complex scenes, this may not work. Could you elaborate on what you would like to do? Maybe there is another workflow for it.

[Guest]

Thanks.
I mostly work with the fisheye doing 4k dome renders, and it's often useful to use an additive material for glow or glare or other things so that I can cut out a time-consuming composite step later.
I'm also having a little trouble getting my head round how self-illumination works in V-Ray. The result of applying a map to the slot is very different from the standard max material.

[hermit.crab]

You can add bloom and glare through the V-Ray Lens Effects within the V-Ray Frame Buffer without the necessity for compositing. Regarding the self-illumination, it seems to work in a similar manner for both materials. When light shines on self-illuminated objects, the diffuse color is mixed in the result, otherwise, it produces the set color. When using a map, the self-illumination colors are taken from it.

[Guest]

Thanks. I've been using the Lens Effects heavily!