From what ive heard, the aluminum supports which line up with the Reflexite tape are reflective. The other supports are supposedly painted black, but im not sure about that one. I know that they do line up, but im not sure if the optical sensors can detect the aluminum through the grating.
While the white tape line cuts off where the ramp starts, aluminum ramp supports continue up the ramp and the surrounding supports are painted black(Team update 2 or 3).