Question regarding bitmap masks


Permit me to be a heretic . . . for the moment, anyway.

A rail simulator player, I make my own content, trees and bushes, included. Using gmax and the associated gamepack, I was able to make those things in one two ways.

  1. I would create an Alpha channel in the art program, such as Paint Shop Pro, adding it to gmax, to make the tree or bush.

  2. I would also, sometimes, create a white mask, using that in gmax to create the same effect.

Thus far, in Blender, I can create those objects by using the Alpha channel, generated in Paint Shop Pro.

However, I have, thus far, been unable to find a way of using a bitmap mask to do the same thing.

Am I able to use a bitmap mask in Blender? If so, how do I go about?

Any help will be greatly appreciated.

Thanks in advance,



I’m pretty sure you can only use the alpha in the image file, not a separate mask image.

I suppose you are talking about materials in blender, in that case you just have the image map as one texture, then the black&white alphamap as another texture but in the map to-settings you set it to alpha and no color. If it doesn’t work directly, set the material alpha to 0 and the alpha map blending mode to add.

btw use the support forums for questions:rolleyes:

I had a lot of trouble finding how to use a separate bitmap mask as an alpha image, but I did figure it out.
Load up your alpha texture, and under the texture panel, make sure “use alpha” is off. You can then set the material to use it as alpha. Otherwise the alpha has to be part of the image.