How to fracture your object according to pre-existing polygroups or materials?

Hi all,

Does anyone know how you could create a geometry collection in ue5 existing out of predetermined objects or from polygroups or materials?

Example: I build a virtual lego set in bricklink and now have it as an fbx where every brick is a seperate object. I’d love to use the chaos destruction on that lego set, and would therefore need to convert that lego set to a geo collection, with every seperate brick as a fractured piece.

Anyone any idea how to accomplish this?

There doesn’t seem to be a way to do this yet -without- first fracturing the geometry. However, once fractured, individual meshes will have convex hulls generated for them correctly, with each piece separate.

The only workaround I currently know of would be something along these lines: use planar or similar to create a tiny cut on a corner, and then use the merge small pieces feature to merge it back to its parent. This should let you do what you’re after.

It’s probably something that’s been overlooked by Epic for now and might be worth a feature request, especially considering it shouldn’t involve much based on how it already works.

@SamGielen if you bring in your FBX with where every object is a separate object say a fracture from houdini. All you have to do is drag all the chunks into the world at the same time. And while they are all selected you can then make your geo collection. Now each chunk you brought in is its own piece in the geo collection. Then you can use the interactive tools to select each fragment you want and then you can fracture it even more or do what ever.

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