Trying to Import large town model for easy "walk through" interaction

Hello all,

Very new to UE4 but am trying to do something fairly revolutionary in the planning design world. We have a large model built in sketch up of a 400 acre site with nearly 2000 home units 7000 trees and a myriad of streets and side walks in it. I am trying to import this model into UE4 but am having a lot of issues getting the parts to work in UE4

I am exporting each model part separately as Sketchup cannot handle exporting the whole file as .fbx

When I export the terrain file i get an un-scaled model with many holes and probably 90% missing faces.

What is the best way to get this model into UE4 so that clients can walk around the site like a video game?

I have at my disposal… Sketchup, Rhino and Cinema4D.

I have included a screen shot of the model in Sketchup and one of how the terrain looks imported into UE4.

Thanks in Advance!

That terrain is going to ruin the performance for you even if you can import it. You need to generate a heightmap of that terrain and then import it as a landscape in landscape editor.

If you want those specific trees and nothing fancy and realistic, you need to export a single one of them and then import it into UE4 as a static mesh, then fill the environment with foliage tool.

The buildings depend on a couple of things:

Is the user going to be able to enter them? Are they(houses especially) unique buildings or are they all the same building just duplicated and placed accordingly?

Jacky thank you for responding!

I am unfamilar with heightmaps but have read some stuff. Would I loose any detail level in the model by creating a landscape this way? the site is very large and has a 6 inch curb cut out of all the streets and i would be afraid to loose that by creating a height map.

The trees are located in places that reflect real world conditions. Is there any way to import the trees as they are so as to not have to put them all back into place by hand?

The buildings are simply shells. They cannot and should not be entered by the user. The houses are 14 diffrent components duplicated across the site so that one of those 14 components might be duplicated 100 times across the whole site.

The idea of this is to allow international clients to download a game app which lets them “walk” around the site, around the buildings and across the landscape allowing them to see an infinite amount of views.

If we can pull this off some how it would be a game changer in the planning/architecture world.

Also if you know of some one with the skills to help us get this model into a gaming platform like UE4 there could be a working relationship started.

Thanks again!

Roads being a part of the terrain makes things complicated. And to bring all of the trees as a single mesh will cause performance issues as there will be no culling. You can easily place them wherever you like with the foliage tool though so that’s not an issue. Contact me at and we can work together if you like, depending on the time constraint you have on this.

Jacky I have sent you an email. it will come from an Ekistics account.


Hi Delancie,

Sorry to be the one to tell you, but the way that Sketchup generates geometry to represent the models you make in it is absolutely horrific.

Your scene will be filled with concave ngons that won’t render properly in other 3d engines (door frames are a classic for this).

There is no uniformity whatsoever in the direction that the polygons face, so half of them randomly will be facing inwards instead of outwards on your models which will look like there just isn’t a polygon there in a game engine. Sketchup doesn’t care about this internally because it just renders its polygons as double sided and seems to have its lighting and shadow system setup with dodgy fixes to work with this but any (most?) other engines will usually render polys with inverted normals as completely black.

And as a final kick in the guts, none of the walls (and other stuff) in a building are actually connected (welded) to each other internally as a continuous mesh in the editable polys that 3ds Max makes when you import them which makes it very difficult to quick fix them with a normal modifier and its unify normals option. And if you try and weld vertices with a very small threshold it causes more problems than it solves.

All of this grievance is very fresh for me as you can tell, I just finished the following flythrough which was based on a sketchup model provided by the architects: - YouTube

The list of issues I had to fix in the model felt endless, I always started by trying various quick fixes in max but in most cases ended up having to just completely remake the broken part in max.

You MAY be able to reduce some of the concave ngon issues by choosing triangulate mesh option in the export options in Sketchup, but my experience with this was that this was also hit and miss.


Thanks for the update. I have always known Sketchup to be a bit of a 3d modeling “light” software with its faults.

Has exporting the model from SU into Rhino or Maya and converting back to mesh helped at all?

Can’t say about Rhino or Maya, as I’ve never used them. Can say that 3ds Max was a champion but as I mentioned, in a lot of cases I still had to just manually remake parts of the scene from scratch in 3ds Max.