| This is more a general OpenGL question, but it is for a Mac project, so I'm hopeful it is permissible here: I'm drawing a number of textures with alpha to context 1 using (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA), and in context 1 things look great. But then I'm using context 1 as a source texture for drawing to context 2, and am getting some artifacts where the original drawing in context 1 involved alpha values other than 1 or 0. I assume this is because, as the spec says, blending affects the alpha component of the destination pixels as well as the color components, so that when context 1 becomes a texture, it has non-1.0 alpha values in it. And indeed, if I turn off blending for the draw from context 1 -> context 2, everything is OK. But for a variety of reasons (I'm simplifying the situation to describe it here) I can't adopt that solution. So, my question is: once drawing into context 1 is complete, is there a way to force all of the alpha values in context 1 to be 1.0 before drawing it into context 2, so that it will draw correctly even with blending enabled?
Many thanks for any thoughts.
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