Hello, I am a new user to UE4. I am importing a very large scene from 3DS Max as a FBX. The mesh has 5.5 million polygons and 6 million vertices. Before I begin the import I get the following message:
Attempting to import a very large file, proceed?
File Size: 319 MB
After 10+ minutes the editor seems completely unresponsive. Is it normal to wait 20 to 30+ minutes for import? System specs below…
AMD Phenom II x2 3.3GHz CPU
8.00 GB Patriot Gamer Series RAM
2GB GDDR5 EVGA GeForce GTX 660 Super Clocked edition
64-bit Windows 7 Ultimate
I do see that it is working on the import, but after waiting it finally crashed. Triangulate? I am not choosing any options in the export, just the 2013 format setting.
There are a couple of known issues that have been fixed and will be in the lastest update. You can work around them in your asset. The known issues and workarounds are:
If you are importing materials and textures with your asset ensure they all have unique names.
With such a huge mesh you may have more than 64 materials. We dont support more than 64 materials per mesh in order to keep the draw call count per mesh sane and not reduce performance. I suggest combining materials or breaking apart your mesh into multiple meshes if that is the case.
It is a static mesh, I followed the documentation for importing/exporting a static mesh and selected triangulate. However I am still getting the same result. Is it completely unrealistic to use a scene of this size in a single import? Breaking this apart would be a nightmare, the rows of stairs in my stadium contain 1 million polygons alone (its a full scale stadium including concourse so this serves as the entire world for my UE4 application). I would really hate to decrease quality of all 200+ meshes or import them individually.
There is no scale requirement or limit. To make sure it isnt issue #2 try importing a version of the mesh with the same material for each poly. There can only be 64 material id’s per mesh.
Import materials is the act of the FBX importer importing, creating, and hooking up material assets for you. Still, each triangle has a material ID which is used to batch triangles together when drawing. Triangles with different material id’s cannot be batched since they would use a different shader. You cannot have more than 64 of these ID’s in your mesh. If you have more than 64 materials on your mesh in maya/max then that would do it. The reason for the limitation is to reduce draw call count.
Perhaps I’m confused but if I do not import materials does this still occur? The original mesh may indeed have > 64 materials, I am about to check, but I have been excluding all textures and materials during import.
OK. I apologize for the ignorance on the importer but that makes a lot of sense to me now. I appreciate the extended explanation I will look into this now.
To be clear about the fix coming in the next build: It will fix the crash but you will still be limited to 64 materials. Anyone can of course change this value in the source code to be higher (at the risk of performance).
I am no longer experiencing the crash after removing all materials from my scene in 3DS Max but now the editor is hanging on the Building static mesh 100% step. I waited quite a long time and the editor appears to be completely locked up. I will try degrading the polygons further but I am still unable to import the mesh.
I also tried not merging the meshes and it never seems to even build the first mesh (even though its a rather small one, few thousand polys).
Now this is quite old of a question, but I’d like to post some research I’ve done on this. I’ve been trying to import my own huge mesh (split into separate objects) in UE4. 2.2 mln vertices total. Towards the end of the process, UE4 tries to allocate ~32 GB of memory… For whatever reason. So yeah - that’s why it freezes and crashes.
I will look into this now.