View Full Version : bump maps with weight maps and gradient colors bug?

08-30-2004, 07:31 PM
I'm creating a plesiosaur (loch ness monster dino) which has one bump map on it's body (cylindrical) and another bump map on it's flippers (planar). In order to use both on the same skin texture I separated them with a weight map I painted in modeler. Works great for the bumps! But then ...

I added a gradient color map to this entire texture and gave it an input of "bump map." Normally this makes the pits in the bump map one shade and the hilights of the bump map another. A great way to make creases look like they are filling with dirt. Unfortunately, the gradient shader ignores the weight maps I added for the bumps to isolate the two different bump textures. It ends up interacting with both bump maps together over the entire object. Arrghgh! Copying weight map alpha channels from the bump texture to the color texture doesn't work.

It does the same thing if you make a diffuse gradient texture with bump input. The weight maps are ignored. ANyone else have this problem or a workaround? I guess I will have to bake one of the textures to get it to work right. Sigh, it was such an elegant solution too!

08-31-2004, 03:14 AM
I noticed this too, it's not what you'd expect. Maybe you can use the same weightmaps as an alpha layer for the color gradient to fix it ?

08-31-2004, 11:04 AM
No I tried that and all it does is isolate the problem on either the flippers or the body.

08-31-2004, 08:56 PM
Have you tried just assigning the surface of the polys to each part and using the same texture on both surfaces? This should eliminate the need for weight maps. Doing this though may cause problems where they meet.

09-01-2004, 10:10 AM
Hmmm, thats weird. I just tried it here and it almost works. But somehow I can't isolate the surface color and bumpmap color gradient complety. The alpha layer doesn't work as expected when used with a color gradient that uses the bumpmap channel as input. But I was able to keep the part that I wanted the bump-color-gradient not to affect free from any color splotches and bumps with a weightmap gradient in both, the bump and color channel.

No I tried that and all it does is isolate the problem on either the flippers or the body.

09-01-2004, 03:06 PM
I can't use seperate textures as this is an organic single skinned creature and seams would show. If it were a robot or something with parts then no problem.

09-03-2004, 02:10 PM
Although the upgrade is very helpful it didn't help me on this issue :(

09-03-2004, 06:05 PM
What you can do instead, is copy all the channel which make up your bump+alphas, paste them in the colour channel, then add a colour gradient BETWEEN your bump and acompanying alpha. This will make it work like you want... Bit cumbersome though. Report it as a bug to [email protected]