Flashing world

We finished refactoring the ninth puzzle and placed it in a sort of courtyard in a museum. Then, we redesigned the ceiling of the courtyard and did a walk-through to check out the puzzle and the courtyard.

At that time, we felt that a sense of perspective was necessary so we set up fog, but then a problem arose.

When moving or rotating the viewpoint, there is a visual glitch where the whole screen flashes. It seems that the lightmap used for global illumination is sometimes applied and sometimes not applied.

This is especially noticeable in dark rooms, where the brightness alternates, as shown in the two images below.

We first suspected the fog that we had set recently, and tried changing the settings back, but it had no effect. We also reviewed various settings, such as the lighting in the scene, but the cause was unknown, so we tried re-baking the lightmap, but it had no effect.

Continuing investigation.