def extent2(texture):
    """ Returns the extent of the image data (0.0-1.0, 0.0-1.0) inside its texture owner.
        Textures have a size power of 2 (512, 1024, ...), but the actual image can be smaller.
        For example: a 400x250 image will be loaded in a 512x256 texture.
        Its extent is (0.78, 0.98), the remainder of the texture is transparent.
    """
    return (texture.tex_coords[3], texture.tex_coords[7])