Vray camera material override

[Dariusz Makowski (Dadal)]

Heya

Is it possible in vraya to set up material so it behaves as it was set up with reflections and so on but it renders black. So I can render a correction for objects and have them being affected by other objects as they should and be cut out by other object geometry. I want to render correction but don't want to render entire image. - not sure if any of that will make sense to u guys

[Svetlozar Draganov]

It doesn't make any sense for me - would it be possible to give us more detailed description of what are looking after.
A samples scene + a few screen-shots along the description would be very helpful as well.

Thanks in advance.

[Dariusz Makowski (Dadal)]

Uh sorry, yea I'm terrible at explaing.

Here is screnshot :


So basically. I want the square box to render black but reflect/refract/cast gi/etc just as it should. Basically I want it to render fast and only focus on renderign sphere - basically I'm doing a correction and I need it to be cut out by other objects as it should but I want all other reflections and so on remain as they should.


p.s. ok sorted. But I have to make override for all shaders and so on by chand, is there a way to make 1 override or I need to do it 1 by 1?

[Svetlozar Draganov]

It seams that you've already sorted it out. Unfortunately there is no way to use only 1 override , you have to plug the original shader into all override-shaders except the V-Ray Material override otherwise the end result won't be accurate.

Another solution could be to make the object Matte-Surface - it will be still visible in reflection / refraction / GI and etc but it won't be visible for camera-rays:



In that case the color of the object won't be black but you could remove it from Alpha channel if you set Alpha Contribution = -1 and later on use that alpha channel to cut it during the compositing stage.

[Dariusz Makowski (Dadal)]

svetlozar_draganov - OMG ! Thats exactly what I wanted!!! Love u soo much right now xxxx

Thanks, bye.