Black Marks Appearing

Hey there,
I have been having weird black marks appearing on my model. Anyone have any idea whats going on?

Thanks
Colin

do you have a lightmap?

yep 2nd light map uv set, in spacing of 0.2 (maya) and inside the box.

Your mesh is probably too complex, default lightmap resolution is 32 which is very small, but even if you increase it to 1024 that probably wouldn’t be enough. For what you’re doing you shouldn’t have the planks modeled individually but rather you should be using a texture map, then you can use a more reasonable resolution for the lightmap and not have those problems.

Do you also have a lightmass importance volume in your level?

I agree with darthviper, a lightmap like that would need a really high lightmap res, I also agree with him about using a texture map however if this is not for use in a game you could probably get away with just having less UV islands, for example you could have the entire floor as 1 island, one of the slants of the roof as another…

The floor and the roof are separate uvs/mesh, I am trying to get it as high quality as possible without having to bake it all down as the texture itself has normal maps also.
I have added the lightmass importance volume but no change.

all my problems with that black marks dissapear changing (increase) in UE4 the lighmas resolution option, by default its 32 and sometimes with detailed meshes must change to 128

Is it possible for you to upload the mesh somewhere so that we can take a look at it? -> because normally the lightmap resolution, lightmass importance volume or the 2nd uv channel (lightmap) are causing such problems

2nd uv channel ->

Thanks for all the suggestions! seem to have helped by changing the light-mass resolution to 256 or more.

Thanks again
Colin