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