3 Replies Latest reply on Dec 7, 2006 2:46 AM by duckets

    'add' blendfunction causes alpha problem

    duckets Level 1
      Hi people,

      I'm hoping someone will tell me this is possible!

      I have 2 textures. I want to use one as a regular diffuse texture on my object, and another texture in a
      higher channel, using the #add blend function.

      This works fine, except when my regular diffuse texture has transparent areas (i.e. it uses an alpha
      channel), in which case it becomes opaque when the #add texture layer is applied in a higher channel.

      Using the #multiply blend function seems to work fine over a diffuse texture with an alpha channel, but
      using the #add function appears to completely prevent the diffuse texture below from appearing
      transparent at all.

      Here's a demo (with source) showing the problem:

      http://www.robotduck.com/misc/alphaAddProblem/

      Anyone else come up against this problem? Have any solutions?

      thanks in advance :-)

      - Ben