[UE4] How to disable lightmass on terrain?

TheGabmeister

My Epic Games account for some reason does not work in the UE4 AnswerHub, so I decided to post the question here.

Currently looking for a way to disable lightmass computation for a terrain. At first I thought it was going to be as simple as changing it from "Static" to "Movable," but it wasn't. I can disable all the parameters below; however, I can't seem to find a way to exclude the terrain from lightmass computation.

Was wondering if you guys know of a way to do this.

Obscura

Have you tried disabling the "static shadow" checkbox?

TheGabmeister

Obscura said:

Have you tried disabling the "static shadow" checkbox?

Yes I did. It did remove the static lighting, but for some reason the time it takes to build the lighting still increased.
For my current scene, it takes 2 mins and 30 seconds to build the lighting. When I add a landscape with "fill world" pressed and "static shadow" off, the time increases to 8 mins and 30 seconds.

As a test, I made an empty project with no objects and lighting. When Build Lighting is pressed, it does so instantly. However, when a landscape is added with "static shadow" off, it then becomes somewhere around 30 seconds to 2 minutes to build the lighting depending on the size of the landscape.

I was wondering where this additional computation is coming from.

Obscura

I'm guessing that regardless if static shadow is off it still contributes to the global  light field (volumetric lightmap or sparse volume samples) which is used to provide indirect lighting for movable objects. You can make the given level using fully dynamic lighting by enabling "force no precomputed lighting" in the world settings, and pressing build to remove the existing bake.

TheGabmeister

I see. Thanks for the help.