Random faces rendering black again

[vhunter]

Ok, I rendered my whole scene nicely and correctly with a single light source and GI enabled with one single flat VRAY material. I assigned some more VRAY materials and then the scene started rendering random faces pure black?!??

So I reassigned the entire model the standard single VRAY material again and AGAIN it rendered some random faces pure black. But theoretically, the model is the exact same as it was when it was rendering correctly before, nothing changed - other than it renders wrong now. I need help badly and am very confused! I can render the scene correctly with default scanline renderer.

Oh, and there are no instances in scene.

Thanks,

Vince

[cocolas]

have you tried checking double sided box in the material options??.......is the model from Autocad/ADT??.......if so that might have something to do with it.........

sounds like a normals problem......if the above doesn't work, try to apply a "normals" modifier to the object....and check unify normals w/out fliping....that might help...


paul.

[yukon_cornelius_]

if that doesnt work put a stanard mat on it ..with the ..2sided clicked

[vhunter]

just fyi, the black faces problem was because I had "force 2 sided" checked in the rendering options AND a material which rendered both sides resulting in a black, essentially 4 sided material.

Vince