The torus is where light gets genuinely difficult. The surface loops back on itself, so the form partially hides its own far side, and the light has to wrap around a curve that never stops turning.

Once you can read a torus, you’ll start recognizing the same lighting everywhere—chains, rolled fabric, coffee mug handles, and countless organic forms all borrow the same lighting principles you’ll practice here.

Rotate the camera to see how the torus casts shadows onto itself, the near side dropping shade across the far side. Add lights and watch highlights and reflected light travel around the ring as the surface continuously changes direction.

Once you can read a surface that curves in two directions at once, the Primitive Shapes Shading Reference brings every form together into one composition.