View Full Version : need Texture alpha help...

03-18-2004, 09:27 AM
Ok, Im very confused here…

Here I have a surface, with the color, diffusion, and specularity all running off of gradients based on the bump map.

Now, in the bump map channel, I’ve got one procedural, then another procedural above that for the alpha of the main procedural..

The way I understand it, the alpha, should remove the bump map.. Which it seems to do..

But (this is where I get confused)

With that bump now gone because of the alpha channel, shouldn’t my color, (and diffusion, specularity) all now be gone also? At least the color right? There shouldn’t be a bump there for the gradient to run off of…

Im still getting the color…

03-18-2004, 10:28 AM
Yes it should work that way, and it does with non 'noise' type procedurals.

Unfortunatley, it can take an awful lot of tweaking to get a gradient to cut off exactly where you want it to for a 'fuzzy' noise texture, and as you have found, the normal way of masking off a bumpmap doesn't seem to pass the correct parameters to the gradient.

I have found a simple workaround, that makes it work though.

In your bump map, duplicate the alpha channel, which in your case is the honeycomb, and drag it to *below* the original bump layer, and set the Type to Normal.

The problem definately lies with the way the 'noise' type procedurals work. I didn't notice the same problem with procedurals such veins, honeycomb, ripples, grid, checkerboard etc or bitmaps, they work exactly as advertised.

03-19-2004, 07:51 AM
If you want to block the color as well, put it in the color channel above the layer you want to mask, and set mode to alpha.

03-20-2004, 08:02 PM
Gradients set to bump don't really go by how much bump you see in the render. Notice that changing the overall bump value won't change the colors either. It seems to take the maxiumum values of whatever layers add bump(?)