still cant seem to get black parts of a texture to not draw. i am useing ortho view and am useing quads for sprites but every combo of glblend() i use either modifies the color of my sprite or draws the black part still. i dont wanna have to resort to building a 3d sprite and useing texture coords.

Disabling lighting seemed to have worked for me...

well it turned out it masking, i read up on it and now i am getting what i want.

Blended suf=rfaces are to be draw last in the scene in reverse order Far to Near. The blending operation is done between blending face and what''s already in the frame buffer. YOu see black because at the time when the blended face is placed in the buffer there is nothing there.
Marius

I think beginners tend to overlook the alpha channel. It''s the only way to selectively "blend out" pixels in your texture.

Is alpha blending hardware related? And is it possible for someone to have a videocard not capable of doing it? Or is it automaticly supported if that card supports opengl.

I''ve used black on textures as transparent tons of times and not once have I used masking.

Alex Broadwin
A-Tronic Software & Design
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"if you fail in life, you were destined to fail. If you suceed in life, call me."
"The answer is out there."
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Jeez, I would hope all cards could do alpha blending in hardware, but I don''t really know. Surely those being built today must.

What is "masking" in the openGL world?

ALL video cards MUST support at least simple blending operations if they have a opengl driver (though it does not mean the quality is good nor does it mean that it supports all forms of the blending ops with all pixel formats). a simple blending op would be the default (AlpahSrc*SrcColor+AlphaDest*DestColor) . additive blending is also well supported (SrcColor+DestColor). the more complex subtractive blending may not be supported.

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Original post by ATronic
I''ve used black on textures as transparent tons of times and not once have I used masking.

Alex Broadwin
A-Tronic Software & Design

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I''m with this geezer here (As long as I disable glLighting, glFog and err, glStuff