Blender Git Commit Log

Cycles: Added support for light portals

This patch adds support for light portals: objects that help sampling the
environment light, therefore improving convergence. Using them tor other
lights in a unidirectional pathtracer is virtually useless.

The sampling is done with the area-preserving code already used for area lamps.
MIS is used both for combination of different portals and for combining portal-
and envmap-sampling.

The direction of portals is considered, they aren't used if the sampling point
is behind them.

Reviewers: sergey, dingto, #cycles

Reviewed By: dingto, #cycles

Subscribers: Lapineige, nutel, jtheninja, dsisco11, januz, vitorbalbio, candreacchio, TARDISMaker, lichtwerk, ace_dragon, marcog, mib2berlin, Tunge, lopataasdf, lordodin, sergey, dingto

Differential Revision: https://developer.blender.org/D1133