All images taken at 20 samples. I was curious to see what effect light clashes would have (e.g. when portals point at each other from opposite sides), and what would happen if I included a colored glass surface.
no portals:
with portals on all openings:
portals on only the righthand openings and the large round one:
no portals, but with a colored glass window in the round one:
with portals on all openings (including behind the colored glass):
portals on only the righthand openings and the round colored glass:
The second image (portals everywhere) is definitely the best, but adding in the colored glass window in front of the large round opening definitely increased the noise a lot.
