Why can I not build light and swarm fails, and why doesn't light bounce in my room properly?

Hello Everyone,

I have 2 problems which I think are related to each other.

I’m running UE4 Editor (4.2) on Mac OS X and I can’t seem to be able to build lighting. It just says that swarm failed to kick off. Now I researched forums and from my understanding swarm is windows only?! So how do I build lighting on MAC because I get “preview” shadows.

Second question is on why the light doesn’t properly bounce in my room? I have a room with several windows together with directional light. What I get is only lights in the shape of windows reflecting on the floor, no fill light in the room. what would be the problem with this?

I attached 2 screenshots with how the room looks like and what are the directional light settings.

Thank you very much.


Dropbox - Screen Shot 2014-06-23 at 7.57.55 PM.png - Simplify your life Dropbox - Screen Shot 2014-06-23 at 7.51.12 PM.png - Simplify your life

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Thank you.

Eric Ketchum

Hey kokozaurs -

Swarm is UE4’s light building and not specific to Mac or Windows but is specific to Unreal, so it should be working for you. Are you running the engine from a downloaded GitHub account or from the downloaded Launcher?

Your directional light issue will probably be fixed after the light build and Swarm is able to add the indirect lighting contributions to your scene. If nothing else it will get us closer to solving that issue.

Let me know -

Eric Ketchum

Its source from github (4.2.1) and compiled in xcode.

I fixed the issue. Built light mass in Xcode! thanks!

can you explain what you mean by, “Built light mass in Xcode!”? I am having the same problem you had and have no idea how to build light mass in Xcode.