Trying to set up a geometry collection and an anchor all in the same blueprint?

Development Programming & Scripting Blueprint
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I’m trying to set up an actor that has one destructible object that is attached to a none destructible object. For example. a sign on a sign post, where the sign can be smashed up into pieces but the post cannot. I want to use Unreal’s Chaos fragmentation system but geometry collections are free floating so they just fall to the ground from where ever you spawn them in.

I understand that you can use anchor fields to set certain fragments to be static and that is great, but I want to avoid manually setting up an anchor for every sign in my game. I have tried a few things with no luck so far:

  • I set a geo collection and anchor field as components of my actor, and set the initialization field of the geo collection both in the constructor, and begin play.
  • I tried using “Set anchored by box” node on the geo collection in begin play with the same setup as above.
  • I tried spawning in an FS_Anchor_Field_Generic actor at a desired transform and set the initialization field of geo collection in begin play.

None of the above have worked so far The geometry collection is still not getting anchored, and I’m not sure why.

How would you guys make an object like this with a very distinct breakable and non breakable parts, without creating a separate anchor actor for each one?

2

You can do it in many ways, however the easiest approach is probably to manually fracture / cluster it.

In the Fracture tools menu, there should be Mesh Cut. You can cut your mesh, then on Level 2 or higher fracture it more with Cluster or similar tools. You can give different damage thresholds to different levels/clusters, and keep the parts you do not want to crumble with a very high threshold, or anchor the root/support part.

Alternatively, you can just divide the post and the sign into two separate mesh objects. Keep the post as a normal non-destructible Static Mesh, and make only the second mesh/sign breakable/destructible as a Geometry Collection.

Here is the tutorial by Epic Staff: