Overlapping volumes render incorrectly with branched path tracing
Closed, ResolvedPublic

Description

This bug is verified on macOS and Linux in commit c723e91ee155612b68950ca2a44b49bdd3c72838

Git bisect points to commit cd023b6cecb7b8c74de1d16510ad09668b86001f as the one introducing this bug. Said commit was part of D2766.

Stefan Werner (swerner) triaged this task as Confirmed priority.
Stefan Werner (swerner) added a subscriber: Cycles.

It looks like this happens with plain transparency too - branched path tracing and plain path tracing give different results. See the attached scene.

Thanks, that was quick.
You're right, D2766 only made the issue more visible - it was present in earlier revisions as well when the min transparency parameter was set low enough.