A room lit from two sides

Somewhere I read that people prefer to be in rooms lit from two sides. Recently Rilkekind got his long-awaited surgery to fix his insides, and everything went as well as could be hoped. Still, he wasn't very happy for several days. We were in a two-crib hospital room and were separated from the window by the curtain giving the other family privacy. Rilkekind spent a lot of time pointing out the door toward a glass door opening on an outdoor patio. Then on the second day there the other family went home, the curtain was drawn back, and the room was lit by the window and the door - and Rilkekind started looking happy.