From Anders F Bjorklund: When switching to "UNIX-style paths" as needed for the new includes, including <GL/gl.h> and <GL/glu.h> doesn't work anymore on Mac OS... The two headers are really located in the OpenGL SDK 1.2 CFM like this: OpenGL:Headers:gl.h OpenGL:Headers:glu.h There are also some compat copies, that *used* to work with Mac paths: OpenGL:Headers:GL/gl.h OpenGL:Headers:GL/glu.h The easiest fix is to make SDL_opengl.h include the proper header names, by adding a special case for the MACOS platform in addition to the MACOSX

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