Re: [PyOpenGL-Users] problems with transparency

[Erik J. <ejo...@fa...>]

On Tue, 26 Sep 2006 21:02:04 +0200, "altern" <al...@gm...> said:
> hi
> 
> i am trying to get transparency with some png images that have alpha 
> channel. But i just get to see the alpha channel itself. I mean i get 
> the transparency but the image is black, like all colors but the 
> transparency have been deleted.

That's a strange problem.  Do you have something like:
 glEnable(GL_TEXTURE_2D)
 glEnable(GL_BLEND);
 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)

in your initialization?

Another thing you could try is replacing:
gluBuild2DMipmaps(GL_TEXTURE_2D, 4, w, h, GL_RGBA, GL_UNSIGNED_BYTE,
bin)

with:
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, GL_RGBA,
GL_UNSIGNED_BYTE, bin)

I've used mipmaps in the past, but I don't have the code readily
available.

if you are still having problems, you could look at this:
http://disruption.ca/gutil/example2/example2a.html

Erik