Light Map's acting silly

jordan.kocon

So I am still getting a feeling for UDK. Can anyone explain why my light map in certain areas is acting really funny? I have a 2nd UV set with evenly laid out UV's, with no overlapping. Most areas of the lightmap look fine, but as soon as areas start to get dimmer the light map looks like garbage:

Render view:


Left of the door:


Behind the camera:

unstoppablex

lightmaps do funky stuff when they aren't receiving any light, or barely any. you can either turn up lightmap resolution or add a skylight or some other light so that lightmass can correctly calculate the lighting for that mesh. it can be real dim so that you still get a similar effect. if that doesn't work, maybe disable lightmaps for that mesh so it uses vertex lighting, which may look perfect since it isn't receiving any light.

jordan.kocon

unstoppablex: Thanks for the reply! Unfortunately the whole 'shell' is one piece, so disabling light maps would affect the whole thing. But I will try just adding some extremely dim lights.

Sandro

That's lightmap compression which can be disabled by setting bAllowLightmapCompression=False in UDKLightmass.ini.

jordan.kocon

Sandro: Cheers dude, that fixed it Thanks!

PointlessReboot

While that may fix your issues, you are going to want to be careful with this as it now makes your lightmaps consume 4x the memory.

Sandro

True. However, you can get away with lot lowres lightmap resolutions when they are not compressed, so that can smooth out some of potential memory issues.