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View Full Version : Trouble mounting a texture on a transparent square



sgeos
07-28-2002, 06:39 PM
Hello,

I am trying to put a texture with transparent areas on an invisible square. I can put it on a square, but the square shows.

When I use an alpha test, the entire unit is either visible or invisible based on the square's alpha value. Likewise, when I blend, the entire unit is blended based on the alpha value.

I know this is possible. I hacked the billboard example by David Blythe and got it to display my texture. By pressing 'b' (or 'a') the box it is mounted on becomes invisible.
http://www.sgi.com/software/opengl/advanced97/programs/programs.html

So far I have been unable to extract what I need to do from that code. I imagine I have missed something simple.

-Brendan

owcs
07-28-2002, 11:36 PM
sgeos,

you might want to check the blend function you are using. the problem might be there