Does OpenGL support color keying? [Archive] - OpenGL Discussion and Help Forums

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07-13-2001, 11:24 AM

Does OpenGL support color keying, that is supported in Direct3D? How can I enable and set key color?

Another point, I have RGBA image but how can I take effect of the alpha channel? I can set the A - values to 0 or 128 or what ever, but it doesn't affect anyway!

DFrey

07-13-2001, 11:40 AM

No, OpenGL does not support color keying. You have to convert the color keyed image to an alpha-keyed image, and then enable alpha testing to reject the keyed pixels.

To see the effect of alpha, you need to enable blending and select an appropriate blending function.

[This message has been edited by DFrey (edited 07-13-2001).]