VRAY and alpha

[tico3d]

hi!

i got the following problem:

i need an image rendered with ist alpha channel

i need the alpha channel to be affected by the transparency of both shadows and reflections

how do i do that?

im using 3dmax and vray as renderer

i can do the shadows, but not the reflections

see attached images

[Christopher Nichols]

  tico3d said:

hi!

i got the following problem:

i need an image rendered with ist alpha channel

i need the alpha channel to be affected by the transparency of both shadows and reflections

how do i do that?

im using 3dmax and vray as renderer

i can do the shadows, but not the reflections

see attached images

 

Alpha of a object in a reflection is very tricky. Actually, besides writing a custom renderman shader, I don't know of any way to do it in any rendering engine... There may be some scripts out there, or some special freebie plugins...

[tuekappel]

I suppose you are using the Matte object parameter in the Vray properties? and sets the alpha contribution to -1?

[tico3d]

  tuekappel said:

I suppose you are using the Matte object parameter in the Vray properties? and sets the alpha contribution to -1?

i could get the opacity of shadows, but not the reflections

and im not using the obejct parameters to achieve that. im using the material parameters instead like this:

[Tim Saunders]

is this different than enabling the frame buffer and using the g-buffer channel for reflection?