Spheres are just a super simple and dead obvious way of showing that your rendering engine is able to do realistic reflections. In the demo, there are actually

Spheres are just a super simple and dead obvious way of showing that your rendering engine is able to do realistic reflections. In the demo, there are actually lots of much more subtle reflective surfaces that contribute to the realism of the scene. > .. critical part of the gameplay .. Strictly speaking, graphics hasn't been a critical part of gameplay for a long time. I think we've mostly gone beyond the point where increasing graphics capabilities actually enable new gameplay.