GL_NV_texture_rectangle http://www.opengl.org/registry/specs/NV/texture_rectangle.txt GL_NV_texture_rectangle GL_TEXTURE_RECTANGLE_NV 0x84F5 GL_TEXTURE_BINDING_RECTANGLE_NV 0x84F6 GL_PROXY_TEXTURE_RECTANGLE_NV 0x84F7 GL_MAX_RECTANGLE_TEXTURE_SIZE_NV 0x84F8