In this two part tutorial, you will learn how to decide which secondary GI solver you should use depending on a scenario, and how to correctly utilize Corona's portals.
This second part explains how and when you should use Portals in Corona.
Part1: https://www.youtube.com/watch?v=vJHFlCLIyFo
Part2: https://www.youtube.com/watch?v=V5J2x2eIHUI
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