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LPV GI diffuse bouncing light flashes.

I am using LPV GI in my ArchViz project to get better dynamic indirect lighting. However, sometime the diffuse bouncing light flashes when 2 surfaces with different lighting conditions (often 1 is brighter another is darker) on screen.
Sometimes it works stably sometimes it doesn’t. I have tried to change the values in LPV section in PPV, but none of them fixed this problem. Any ideas on this?

LPV is not a good solution for archviz, if you’re looking for a dynamic GI solution then I would try Nvidia VXGI

Yeah, LPV isn’t very stable and it’s not really possible to get it to work 100% consistently. I usually get a lot better results with a skylight.

I tried both LPV and VXGI. VXGI definitely looks better and very stable I have to say. However, I still hesitate to use it as it is expensive and secondary diffuse bounce need about 8ms to render my scene at 1080p.
Another reason I use LPV GI is I managed to get both LPV GI and VXAO work at same time, the result is really close to VXGI and VXAO is more realistic than HBAO+. I am satisfied with this combo. The only problem is LPV.
As I test many times, LPV is very possible to flash when different lighting conditions appear on the screen. I really want to get LPV stable, but I don’t know how to do it.

Skylight solution was my original solution to simulate indirect lighting. The problem is that my scene contains forest and skylight doesn’t provide depth in it, so I switched to use dynamic GI.

As mentioned above, LPV just isn’t very suitable for Arch-Viz scenes. You’ve already managed to get the best out of it, which is ‘stable most of the time’. Have a look at the KiteDemo, it contains many useful blueprints on how to get a ton of different outdoor lighting variations. You might also try Heightfield GI (landscape required).

Thanks, will check details of KiteDemo.