mmp
There is no ambient occlusion (AO) effect in the corner.
This is the image rendered by PBRT. There is no ambient occlusion (AO) effect in the corner, and it even looks a bit bright. What should I do?
The most likely explanation is that that is an accurate rendering of the scene. If you think there is a bug in pbrt's path tracer, try to find a very simple example scene that shows that there is a bug.
This time, I only used a simple model.
Here is my pbrt file. "skybox.exr" is too large, and the upload failed. AO.zip
After some time of thinking, I think it's because there is light leakage at the corner of the wall. Is this a problem that a path tracer cannot avoid?
That's a reasonable theory. You might try extending the edges of the wall further out to see if that makes a difference. In general, light leaks are not usually a problem with path tracers. See this to learn more: https://www.pbr-book.org/4ed/Shapes/Managing_Rounding_Error.