Need to reimport to get custom collision to work

This seem to be an bug, when I have a FBX with both LODs and Collision meshes, when I import the file into UE4, it only seem to import the basemesh and the LODs, but won’t import the collision meshes until I rightclick it in the content browser and choose reimport.
Sure I can just reimport after importing, but that’s not really a proper solution.

I’m using 3DS Max 2016 and UE4 v4.13.3.
The basemesh, LODs and UCX are all in a group, UCX attached to the basemesh, and selected the group, basemesh and LODs and applied Level of Detail set to it, and then exported it.

As an separate issue, if you have Transform Vertex to Absolute disabled, the collision is not in the same location as the basemesh.

Hey McGreed,

I was able to import a mesh with LODs and Custom Collision without any issues. My workflow was a little different though.

After I set up the LODs for the meshes I then modeled out the custom collision Geometry and gave it the UCX naming convention. I didn’t add it to a group or attach it. If you would like you can send me your FBX or MAX file to test with to see if I can reproduce the issue on my side. You can PM me here:

Also here is the FBX I tested with.

Regarding the other issue you mentioned would you mind making a separate AnswerHub post for it as others who are having that issue will find is easier that way.




for replying. I have tried to import your model, and it does seem to import the collision right away with no problem with the same settings I use to import my model. I included a screenshot of the import window setting. Sending you a PM with link to a FBX file I have the issue with.

Did your workflow of parenting collision meshes to LOD0 ever work for you in previous versions?

I was able to get the model to import correctly after removing the collision meshes from the LOD group.

I would recommend keeping the Collision Meshes as separate and not made to be children of any of the LOD meshes. There is no real advantage that comes from parenting your collision geometry to your base mesh.

Other than keeping things neat and organized in Max that is. :wink:

The main reason for doing this is that I made a script for exporting, which will mass export all the models that is in my selected groups, and export them individually, with collision and LODs.
Since 3DS Max crashes if you have the collisions in the group alongside the basemesh and LODs, this is the only way I can export them all together, without having to do some scene searches for collisions.

Just updating you, a bug report has been filed here: Unreal Engine Issues and Bug Tracker (UE-42141)

Feel free to track the issue as it is reviewed by our dev staff. Keep in mind this issue may not be addressed quickly or prioritized.