Lumen GI and Reflections feedback thread

That is actually the way it should work, when “it works”, its a bug. (I also cant replicate this in the project.)

The Sky Light lights the floor, and the walls, from above - therefore you only get reflected light at the ceiling. More precisely: reflected light that bounced back from the floor. (PS: the 50 for your skylight is completely overkill :stuck_out_tongue: (I think mine is at .1 - but that depends on your exposure settings.)

Sky Light only:

Sky Light + Sun:

Sky Light + Sun + “Fake Light Actor”*:

*That “Fake Light” is a 2nd Sun that doesnt cast shadows and lights straight up, it is needed due to Lumen having issues “lighting upwards” from what I can tell - at least compared to reality.

While Lumen is awesome, it still needs some “help”, which I previously described as “some faking required” to get a good result.**

Low light situations are also troublesome for lumen… I had to come up with a dozen new lights/lamps for my game to deal with that. In fact, the only reason I still have a sky light enabled when Lumen is enabled, is its inaccuracy in dark scenes/areas, thats where the sky light “covers” that.

**This isnt explained anywhere, and it is project-specific. While you will have a relatively easy time lighting up a single room in archviz, dealing with large and complex game-interior that has multiple layers vertically is troublesome. It took me quite some time and experimenting until I got lumen “dialed in” on my specific game with its very specific needs due to the gameplay - just enabling Lumen wont get you anywhere, thats the reality.

I am even lucky, my game has a 2:1 scale for general architecture, therefore I get away with things that wont even work for other games, lumen simply lacks the precision (in software mode) for a lot of the things I do on smaller scale, and even then, sometimes I have to make something slightly larger to still get the visuals I want when the viewport is further away.

Back to that sun temple project… getting the roof lit up at reasonable light settings will be an issue with lumen, at least without faking. (Unless someone has a magic solution that I am unaware of after almost 9? months of Lumen usage now.)

EDIT: That said: I am by no means an Expert when it comes to Lumen, I am just confident in the results I achieved to get with my workarounds.

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