using texture without VRayMaterial

[frueter]

Hi,

out of curiosity: What is Vray doing when a texture is connected directly to the geo as material without the use of a VRayMaterial node?
In the absence of lights it seems to mimic what Nuke does which is great. But as soon as lights are involved it produces a bright edge where the alpha is not solid.
I would have assumed that this sort of "lazy" setup would yield the same as a VRayMaterial node with it's diffuse colour connected to an unpremultiplied texture and the opacity to the respective alpha.

Attached is an example.

Cheers,
frank

[Christophe.Cot]

Hi Frank,

Textures plugged directly as material as translated differently than when going through a VRayMtl node or equivalent - in this case they are wrapped within a BRDFDiffuse plugin.
I looked at the problem you describe and indeed the used plugin calculates something a bit unexpected with a texture with an alpha between 0 and 1.
Without bothering with details, it's something easily fixable.

You can even fix it now using a simple post-translate script :

from vray.utils import *
brdfDiffusePlugins=findByType("BRDFDiffuse")
for brdfDiffuse in brdfDiffusePlugins:
  brdfDiffuse.set("color",AColor(0,0,0,0))

Thank you for reporting this.
Chris

[frueter]

Great, thanks for confirming Chris. It's no big deal, just something a little unexpected for compositors.
Cheers,
frank