GL_EXT_texture_rectangle http://developer.apple.com/opengl/extensions/ext_texture_rectangle.html GL_EXT_texture_rectangle GL_TEXTURE_RECTANGLE_EXT 0x84F5 GL_TEXTURE_BINDING_RECTANGLE_EXT 0x84F6 GL_PROXY_TEXTURE_RECTANGLE_EXT 0x84F7 GL_MAX_RECTANGLE_TEXTURE_SIZE_EXT 0x84F8