[ASK] Sketchup to Unreal Engine 4 model messed up


I tried to convert architectural building from SketchUp to Unreal Engine 4.7.

First, I export sketchup model to 3DS max, UV unwrap them, make a clone as UCX_* for collision.
Everything looks fine in 3DS Max, then I convert it to FBX 2013.
When I import it to UE 4.7 it says warning about degenerate tangent, some wall were disappear, and the collision meshes messed up.

Here is my FBX Files :

How can I fix this ?

Thank you.

Hey there!

Allow me to possibly be the first, but definitely not the last in a long line of people who will recommend any other content creation software over SketchUp -preferably Maya or Blender- for what you are doing. The issue that, at least, I’ve dealt with dealing with SketchUp and exporting is that first, the chances are high that you got duplicate UV coordinates on your UV maps. For some reason, and this happened to me a lot too and a lot of others I’ve talked to, SketchUp really has a hard time parsing 3D shapes so it tends to assign the same coordinates to UVs on top of each other even when you take great care to unwrap your mesh delicately. Generally, SketchUp is great for concepting, but for modeling it’s Maya or the highway (at least for me) or Blender.

Likewise, the conversion process for Sketchup PRO is a little bit more graceful to FBX, I’m not sure if that is what you are using, but if you are going to get SketchUp Pro you might as well just get Maya and get yourself some pro tools. Just my opinion, again, nothing again SketchUp, this is all person choice. Unreal almost never chokes on meshes from Maya though so if you know you will do a lot of work between models and the engine, it may be worth investigating an alternative.

Also, this issue has come up about a million times and I’ve had to read through this same problem a lot for myself and others so I’ll just post the result of what others have gone through to solve their SketchUp issues and maybe that will help you out :slight_smile:

Likewise, this video was super useful. This method only works for Pro, but I don’t know, maybe there is some basic tools use you are missing like cleaning up your mesh of tris or something that could be the difference between exploded vertices, missing pieces and wacky UVs. Good luck!

Hi, Thank you for your quick reply.

I’am using Sketchup Pro.
I’am converting from Sketchup Pro to 3DS model, open it in 3DS max, UV unwrap there.

Well, I’m not modelling those object by myself. I only get the file from my friend. He have lot’s of model built on Sketchup.
So i’m still figuring out how to convert those models to UE without having to remake it in another program and as fast as possible.

Thank you for the thread link. I will try it now.

Also, for the best result, is it best to convert a building model by section or can the model imported as a whole ?
Let say I have two story house, can I just import the model as 1 FBX ? or should I separate the model to a few FBXs ?

If it is a larger building model and after following those steps you are getting missing walls or exploded vertices/blown out shadows then you may want to break it into smaller models and export it again.

Also, and I don’t know if you saw it in the other thread, make sure you are set at 0,0,0 before you export or you will lose pieces and get really messed up in unreal.

I’ve figured why some walls are missing. In Sketchup you can have the object face to be reversed, that’s what causing the wall is missing.
Now I’m trying exporting by breaking the big model into smaller pieces.

Oh good I’m glad you were able to troubleshoot and figure out your issue! What do you mean reversed though? Or maybe I’m just not completely understanding what you mean.

Also also (and I don’t think this is an issue you encountered but I figured I’d put it out there just as a warning) make sure there aren’t any hidden artifacts because unreal will /definitely/ choke on them in the conversion process and your asset will get super messed up.

Here, see this video :

You can see the object from inside but from the outside it is invisible.
In my case, the wall which is shaped like a cube, and one of it side is facing inside that makes the wall is missing. All I have to do is reverse that side so it’s facing outward.

OH! I get what you mean. Sorry, I wasn’t reading correctly. Yes, that makes sense. Well, again, I’m really glad you were able to figure it out.