This is because you are not using unique UVs for lightmaps.
You need to generate a second UV channel in order to get rid of thoses shadow artifacts.
Have you actually created a second set of UVs in that channel? Can you post a picture of those UVs
and here in unreal :
That may not work very well, you’ve got a lot of separate small pieces close together.
Check this for some guides on making UVs for lightmaps:
Also, what is your lightmap resolution on that mesh? You may need to set it higher because there is so many elements.
You need to break your model up into maybe 3 or 4 pieces instead of trying to import it as one geometry. That way you can get larger UV islands on your lightmap when you flatten
Or increase your lightmap resolution.
thanks guys , actually it was from lightmap size ‘32’ , i changed to 512 and it is awsome
As you import more assets, it’s probably best you don’t rely on increasing the resolution too much, and instead edit your UVs. 512 is a bit high really.
In 4.5 UVs for lightmaps are generated automatically on import, which mostly works pretty good.
will update the engine soon , right now i am focused on 4.4 thanks buddy .
Yeah definitely update to 4.5, it saves so much time and it’s much more accurate than automatic flattening in 3DS
Yeah, you need to do a better UV mapping job. Even though you have stuff like the windows extruded in like that, you can keep an entire face of the building together in the UV’s. Stuff like that to reduce the number of UV seams and islands will greatly improve the results for your lightmaps.
i hate this , i cant find solution , i tried my best but it looks engine is missing some light lessons guys … it is aweful …
:mad: this is crazy , maybe that’s from my uvs that are not master correct ? some developer reply me please ?
is this okay ?
Yes all your UVs in 3d max are fine. But make sure that those spaces between UV islands have at least 3 pixels space betwe on lightmap texture generated by engine.
So if you plan to use 32x32 make sure that space between is 3/32 at least. Else you get famous light leaking effect on edges.
Also on second picture you can mirror one of L shapes to have more space.
how do I understand that those spaces are at least 3 pixels distant from each other ? 3 pixels or what ?
3/32 of 1uv space if you plan to make 32x32 lightmap texture, for 256x256 it will be 3/256 parts of that 1uv space.
To see it better just load 32x32 texture as background for your uvmap (or make 3dmax material with that size of “pixels”/checker boxes)
Then yes it will be 3 pixels.
Or calculate grid size for your uv space editor and set it up there.