Hi, I’m devloping a game and I want it to run on everything, even ps4 and xbox one, but Lumen is too heavy for my low end test bench so is there an alternative. I’ve tried gpu lightmass but it doesn’t work.
afaik lightmass currently doesn’t work in world partition levels. (wip to add wp lm levels). you have to make one without it. it should bake then.
The Epic team mentioned in one of their last talks 2025 that static lighting is coming to world partition soon.
Lightmass works in 5.5 with world partition, but only CPU lightmass.
It’s still an option though.
Indeed, and a very good one. There’s a reason we’ve been using lightmaps in games for 20+ years and will likely continue to for the foreseeable future. Nothing beats their quality to cost ratio.
hmmhmm. it’s dirt cheap. static direct light shadows are not so good without high resolution lightmaps, but you can bake rather nice static gi in very lowres fashion.
Ok, I will use CPU Lightmass then, but why is gpu lightmass so broken?
I’m not sure Epic has anybody working on it right now so it most likely just simply broke as the rest of the engine was updated. It’s my understanding that it’s reliant on Unreal’s underlying hardware raytracing implementation which (I assume) has changed a lot in the last few versions of Unreal.
Oh.
well… it got to some degree outdated or updated to be realtime surface cache, we use now. currently it serves no real purpose, in my opinion.
baking complex lightmaps with detailed shadows is kinda outdated in this engine iteration and for large scale worlds. if you need low poly or mobile style lightmap bakes you use the last engine version it worked in.
if you bake gi now you should only bake gi volume data and “lowres irradiance approximations” on surfaces. and use stationary lights and shadow mapping. or mega lights. the latter has some limitations and kinks you’ll have to figure out or use alternative shadow mapping or raytraced lights in certain scenarios, but it works pretty good.
Ok