Transparency Troubles

[AndoF]

Can someone tell me what I'm doing wrong, or is this a bug in the system...as others also seem to be having trouble with transparency?

I'm trying to render a photoreal image of a person in which the background has been removed and the whole thing saved as a standard png...so it shows up fine in SU.

I have then gone to the V-Ray Material Editor > Scene Materials > Add VRayLinkedMtl.

I have then gone to the Diffuse settings in the new linked material and specified the png as the Color. I have also specified a separate alpha map of the figure, which I have saved as a jpeg, in the Transparency settings. I have applied both of these; they both show up as they should in the preview panel (tiling off), yet when I render the image the transparent parts are still opaque.

Also, if I close the Material Editor, then reopen it, the capital M on the Transparent section has gone back to lower case and the alpha map settings have all disappeared. I did make sure I applied them...several times.

TIA for any help.

[Ibontxu]

Re: Transparency Troubles

I had the same problem and here's the solution:

http://www.asgvis.com/index.php?opti...0&topic=2632.0

[AndoF]

Re: Transparency Troubles

Thanks Ibontxu. By trial and error I arrived at the same solution. I found that by checking almost any box in the Maps menu then specifying the same alpha map or a custom made 32 pixel flat gray (which hopefully has the effect of having no effect at all) I could finally get the Diffuse transparency map to "stick" and not disappear again as soon as my back was turned.

I'm curious though; on the thread you linked, it sounds like the trick worked straight out the box. I'm finding that the result is that I get the opposite of what I actually want...the transparent pixels still display but the opaque ones have disappeared. The obvious solution to this is to invert the Diffuse Transparency map in the linked material. This gives you exactly what you want in that particular setup, but unfortunately it can't be saved for future use. I find that if I then save that component as a V-Ray ready file, it imports and displays just fine in SketchUp, but is completely invisible when rendered in V-Ray....I assume because of the reversed alpha.