Some models are collision-free

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revit created a model with a pipe diameter less than 100mm, and the derived 3dtiles could not be detected by radiation in UE, which could be detected by other models


I’ve ran into the same problem with photogrammetry models exported as Cesium tiles from Agisoft Metashape (as well as Reality Capture):

Unfortunately I haven’t found a solution yet, much less the exact reason why and where this problem is caused. I’m not sure whether it’s the modelling or in my case photogrammetry software, the Cesium tiles format itself, Unreal Engine, or the Cesium for Unreal plugin.

I have read your post, and it seems that my problem has nothing to do with the setting of “Maximum Screen Space Error”. Your problem is that the collision disappears after setting 1 and the setting of 16 is restored. The effect of setting 1 or 16 in my model is the same, except that there is no collision in the pipe with small diameter.

I forgot to mention that if “Create Nav Collision” is checked, there are all the small pipes, and if it is not checked, there is no, but if it is checked, the whole scene will become stuck. Normally, I don’t need to check this, because I just use it to query information

Yes, but the underlying problem is the same: That for some reason some cesium 3D tiles do not have collision and that we have no idea where the root cause of the problem is.

Hope to get some other answers

Cesium for Unreal filters out small triangles when constructing the physics mesh. We do this because we’ve otherwise seen Chaos complain about these small triangles and then collision doesn’t work on the entire tile. The code that does the filtering is here:

It could be worth commenting this out and see if it helps in your case. The plugin will need to be located in your project (rather than in the Engine/Plugins/Marketplace directory) in order for code changes to be picked up.

thank you very much for your help