How to customize the exact shape of the chunks inside a destructible mesh?

Thanks for reading. I have a simple question, along with three possible approaches but I’m not sure of the way forward. How can I customize the exact shape of the chunks inside a destructible mesh i.e. make a sphere or box that has chunks shaped like smaller spheres?

Possible approach one: Would scatter meshes in PhysXLab be useful? It appears they might be IF I could make the inside of the 3D mesh hollow. Is the hollowing out something that should happen in PhysXLab or back in Maya?

Possible approach two: a “crumble emitter” particle system. I’m not sure if this would lead to a fixed amount of chunks or not.

Possible approach three: better slice ability? It would be nice if the destructible mesh could be “divided” into smaller copies of its shape, i.e. a sphere into smaller spheres. I’m not sure if PhysXLab or UE4 allow for the chunks to be given a specific shape or not.

Thanks for any help!

First off, Thanks for all the destructible questions. They really are fun to work on! :slight_smile:

With approach 1: I’ve not really used scatter mesh but from my understanding this will only scatter the mesh that is chosen along the surface of the destructible. The scatter will stick to the surface rather than just going it’s own way as a separate mesh.

With approach 2: I’ve not used the Crumble Emitter before. I’ve seen it used for something like a smoke effect, but this can be done in UE4 as well.

With approach 3: There isn’t a slice that will do it that way. The Slice works using the Voronoi method to make the chunks. you can adjust how the slice is affected though not to be the same mesh.

We have in one our internal QA examples (Not sure I can link it here, so I’ll describe and possibly set one up at some point) a barrel that is a skeletal mesh that when destroyed plops the side planks down and the top explodes into chunks. I’ve not set up a skeletal mesh destructible before so I’ll look into that. This is one avenue for better control.

Another that would require using PhysX labs. You can test it in UE4 to get an idea before moving forward by using my test asset.

When you import this only import the SphereShell fbx > Convert to DM > Open and click Import FBX chunks > import SphereInside.

Place in your scene and set up the mesh to destroy. What you’ll see (since UE4 only has one depth layer and why you’ll need PhysX Labs) is that when depth 0 the sphere shell is destroyed you’re left with depth 1 the sphereinside meshes.

Hopefully this is enough to get you started. It will probably take some work to get it right but this is at least the foundation. :slight_smile:


Thanks, Tim! I tried that and it worked. Very interesting. I will have to read up on the “import FBX chunks” function and see if I can get those interior chunks moving around. Very cool that you can import another mesh for the chunks! Thanks for the spheres, made it easy to see your point! :smiley:

Glad that worked for you! I’ve known about it just never used it really to this point. Feel free to update on your progress. I’d be interested in seeing what you accomplish! :slight_smile: