O.k., is transmapping possible in Carrara, or is this another bug issue? I have a b&w map and I want the white part to be fully transparent. When ever I apply it in the Transparancy part of the the shader I get nothin, nada, squat...well, actually I get an outline of the transparent part...I have selected "White Invisible" and still nothin. Any suggestions, comments, or stuff like that is appreciated. Thanx, Jared

If I understand you right (and I'm not sure because I'm unfamiliar with the term transmapping), I think you can pull off what you're after. The image shows the settings I used to create a shader with a cheesy painting of a flower in the color channel and it's black and white transparency map. The trick is to make sure no light interactions occur when fully transparent and I also switched on the light through transparency settings for the final render. I also did slap this shader on a sphere and I put that sphere between the camera and my Imperial Sentry droid with the light positioned so it would cast a shadow the way it did. I inset that render into the image in the lower right corner. Hope this is what you're after. -Kix

-Kix

Kixum...that's exactly the same thing that I'm doing...I think that my problem is that I want the transparency to be a very thin strip and it's leaving that nice little white area in there which is making it not look transparent... as far as the termanology or "transmapping" that's what I've always heard of transparent maps being called...must be a texas thing.. Jared

The way I've gotten around this is to render the thing huge and then reduce it using a 2D program later. It seems to reduce the whiteness some but not completely. Here's my airplane completed. I rendered this about 2000 X 1000 and reduced it. The words and stripes are what I had the white striping issue. This is the best I can do. -Kix

-Kix

good idea! hadn't really thought of that...do you just do a little post render clean up to get rid of the white? or is it pretty small so you don't really have to worry about it?

The white stuff gets pretty small when you render pretty big. The airplane image had no touchup to it at all. Here's the same thing rendered straight at 500XSomething. You can defintitely see the difference.

-Kix

The white is much more visible! I'll increase the res to get rid of it. Thanks for all of your help! Jared

Hm. Here's the results of a little experiement I tried. The sphere on the right used a transparency map that was basically the color map filled in black. The sphere on the right used a transparently map that was a bit smaller than the original. My idea was that the overlap would be the color parts, not the white background. Not sure I'm explaining this very well, but maybe you can tell from the picture. I rendered this at 640x480, no reduction. Might be a bit tricky to do this for complicated texture maps, but for simple ones this works pretty well. Maybe if one started with the transparency sillouette first, and made the color map by coloring "outside the lines" of the transparency map, even complicated transmaps would be doable.

Very interesting but it would seem that it could get very painful for things like the letters I used. You'd have to do some fussing with edge filters in pre-processing.

-Kix

One other consideration in this mess is that the image you use for the transmap shouldn't be a JPEG; something about the compression scheme causes a variation from pure white near other colors. It's not visible to me when looking at the JPEG, but when I tried to map my graphics on the plane here using a JPEG, I got the ugly white border you're talking about. So, I saved the art file as a BMP and suddenly the lines were mostly gone. This is a non-reduced render straight out of RDS.

JPG's do this because they usually flare/fan/anti-alias colors at sharp color borders and leave white looking transitions but they aren't truly white. This is another case where RDS beats out C. Your soft shadows are an obvious second example of RDS superiority.

-Kix

It appears to me that the problem is a simple anti-aliasing issue. The white lines are the result of your 2D program anti-aliasing the edges against the white background to smooth out the curves. The lines aren't actually white, but rather a 1-5% black, which appears as white. Try building your map in Illustrator, or turning anti-aliasing off in Photoshop. Incidentally, the 1% black is a good trick I've used before to have seemingly white portions be visible when the "white is transparent" otion is selected. ty