Improving light build times

I Currently have a 8129x8129 max size landscape and i have a lightmass importance volume encapsulating the full landscape but my build times are still strenuously long and as i have not got much experience with doing maps this large i do not know whether this should be expected or not.

Should i be placing lightmass importance volumes per component of the landscape so that i end up with multiple importance volumes or is it just that there is not much i can do with having a landscape so large?

:slight_smile: :slight_smile:

If you have a lot of foliage on your landscape, it might help to tweak the light map resolution:

Thansk for the answer but no i currently only have the player mesh in the level just to size things out.


  1. By a map size this back even without any objects on it, it will take it’s sweet time. With objects, it will take a lot longer I imagine. What you experiencing is not something absurd :).

I don’t know, if it affects the speed, but I generally turn on the “Standalone mode” in the swarm agent. While you click on “Build Lighting Only”, Double click on this icon on the right bottom corner of your taskbar 110392bfbe7d4d9ca0829fe9d1c8e89b.png and the swarm agent should appear.
Go to settings and it will look like this:

Change the “EnableStandaloneMode” to “True”.

It also makes you less prone to crash, while building lighting. That’s atleast, how I experienced it.

Typically for large maps you shouldn’t be using baked lighting–the issue is that it takes a long time and as you add more objects (especially folliage) then you’ll likely run out of memory. Besides that, the large amount of lightmaps will take a ton of disk space. For these reasons games with large maps typically use dynamic lighting.

I wouldn’t go baked either. Real time lighting has its hit on performance but 20 percent less grass is a good price to pay for not having to make people download 40 GBs of Data…

Turning on Distance Field Ambient Occlusion and Light Propagation Volumes (Unreal’s dynamic GI) is an excellent combination. I have switched to it myself and so far I can only report that the time I saved from building Lighting I spend on being amazed how good this works.

Thanks alot for the replys guys i will look at changing my lighting to dynamic, the whole less foliage thing is not an issue for this landscape as it is going to be a desert type enviroment so foliage will be rather scarce.

Hi guys, I’ve just worked on an asset to improve compile time: Compiler Booster in Code Plugins - UE Marketplace