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Yes, like I said, it is a MIS problem: if you set max path depth to 1 (in .cfg file), it works fine, if set to 2 (MIS enabled), it doesn't. It happens because some cache entry, near a shadow boundary, has 2 entries (sun+sky) others has sky only (sun always not visible there). This change the weights of MIS and triggers the problem.
When corona was introducing for the first time their new light solver that also handles many lights scenarios well. They too had similar issue I think: https://corona-renderer.com/forum/index ... #msg132828Dade wrote: Sun Nov 11, 2018 11:37 amYes, like I said, it is a MIS problem: if you set max path depth to 1 (in .cfg file), it works fine, if set to 2 (MIS enabled), it doesn't. It happens because some cache entry, near a shadow boundary, has 2 entries (sun+sky) others has sky only (sun always not visible there). This change the weights of MIS and triggers the problem.
It should be possible to recreate the problem also with just 2 area lights (i.e. it is not related the light source types but to Glossy code for Sample() and Evaluate()).