So after seeing the initial “demo” forever ago, and now the release today. I was under the impression that Lumen was a fully dynamic global illumination system. After playing with it for awhile in different environments, I noticed LOTS of pulsing of the bounce light during camera movement, similar to the effect you get around edges with say HBAO+ where if you move the object just off camera, you lose the AO.
Below are some tests I did with it, and by all means it’s an amazing solution regardless, it’s VERY jarring though. Something just out of view gives off no bounce light at all in this scenario.
The environment has a default directional light and skylight. The spotlight in the hallway is a default spotlight that’s 100cm away from the wall that’s 0.5 roughness and pure green.
GI Method is Lumen
Reflections are Lumen
Software ray tracing is set to Global Tracing (Still occurs with Detail Tracing, but with what looks like very small amounts of bounce light)
Shadow map method is Virtual Shadow Maps (with regular shadow maps there is light bleed all over the place)
Using hardware ray tracing when available
Ray traced shadows are on
Static lighting is not allowed
Skin cache is on
And of course mesh distance fields are being generated
9900k @ 5ghz
ASUS Z390-I ROG Strix
Nvidia RTX 3080FE @ stock (driver 466.47)
32GB of 3200mhz Corsair Vengeance LPX
Am I doing something wrong, or is this working as intended? It reminds me a LOT of what Pascal Gilcher does with his ReShade script. I’m not a fan of the flickering you get with camera movement and the pop in/out that occurs when occluding/including the light source.
EDIT/UPDATE: Under the Mesh>LOD0>Build settings, enable Two-Sided Distance Field Generation and the problem is solved. Unsure why this fixes it, but it does.