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Feature requests / Video mode color buffer alpha

« on: January 18, 2008, 02:18:30 am »

I noticed that there's no way to request alpha for the color buffer, even when setting a 32-bit color format.  Some OpenGL blend functions require the color buffer have an alpha channel (e.g. GL_SRC_ALPHA_SATURATE, GL_ONE required by polygon smoothing).  My renderer failedafter switching over from SDL, as the alpha-saturate blending stopped drawing anything due to the missing destination alpha.  I ended up locally modifying WindowImplWin32::CreateContex to request an alpha channel for 32-bit and 16-bit color depths, but that's obviously not ideal.  Exposing the pixel format attributes as some sort of "advanced" properties would help.