TL;DR:
Before:
After:
These images are 2 weeks old and there have been some changes to it, as well as a slider to adjust de-noising. Notice how much more pronounced the ambient occlusion is, and how much better the overall shading is. It’s also faster than the older implementation.
On the scene I used for testing this out, the overall rendering time went down from 3 minutes to just over 1 minute in an RTX 3090 Ti with an 8K lightmap.
Bonus: This PR shaves off a massive chunk of the codebase (about 10% apparently.) Expect faster build times and a smaller engine size in 4.2!
As in automated testing. I don’t see CI run nor any code hinting at automated testing.