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Wrong Shading due to UV mapping

My models have no shading problems in the global shading panel. However, when I use my own lighitng and scene, the models get weird shading on unwanted parts of the model as I’ve shown in the pictures. I tried to solve this problem with UV mapping and have no problem in 3ds max also as shown in 3ds max picture(armchair 3ds max) below. Yet when I use the same model within my UE4 scene(armchair) and lightning, I get shades on unwanted parts of the model. How can I solve this problem. What I want is shadowing as in picture 1(armchair2) but in my own scene. Btw, I create my UV maps in 3ds max with “unwrap only” button in the “render to texture” panel.

You used the automatic flatten UV’s option in 3ds Max, which makes a lot of bad seams in the UV map, you can see all the ugly seams there which create jagged edges and small UV islands from the wrinkles and stuff.
So first off you need better UV mapping, to do this you can look for some natural seams in the mesh, since it’s furniture you have the cloth seam which should have a nice complete loop that you can easily select to create your seams.
If you work on the UV’s a bit that will help results, but also after that you will need to adjust the lightmap resolution for that mesh in UE4, you can do this by opening the mesh from the content browser and adjusting the lightmap resolution which is set to 64 by default, you likely need to set it higher, like 256 or 512

Yup, this is definitely due to bad UV mapping. 3DS max has this very useful tool called point to point peeling, take a look at this tutorial
https://youtube.com/watch?v=XtHYHXogotw
Also, don’t forget to sew the uv shells together as much as you can. If you’re making lightmap uvs, then just copy your main uv channel to the lightmap channel and break the hard edges so that each uv shell is separated. You also want to make sure that shells are not too close to each other to avoid bleeding.