Can’t Read Alpha Channel of Textures

I’ve made a bit more progress since last time. It seems that the problem was that I wasn’t getting the alpha value of the texture maps correctly. I found a couple web pages that talk about the problem of alpha channels with glReadPixels, but I think they’re both talking about Mac OS X and not iPhone specific Open GL. I did find one other guy that was doing iPhone stuff with glReadPixels and alpha channels but he seems to have the same problem I have.

Fortunately, in my case, it’s just a single channel stencil mask so I can just copy the red channel for the alpha channel. It’s a bit inefficient and kludgy. But hey, it works. And after spending several days on this one issue, that’s all I care about.

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