I’m working on a project where I want my simulated groom to interact with a collision object that I’ve generated. Unfortunately, despite spending hours tinkering with various settings, I can’t seem to get the groom to interact with the collision model.
I know that the pill-shaped collision pieces generated from a skeletal mesh are the typical way to get a groom to interact with physics, but unfortunately, that method won’t work for my specific scene. My knowledge of grooms is still pretty limited, so I’m sure there’s a setting or trick I’m overlooking.
If anyone has any suggestions on how I can get my groom to interact with my collision model, I would be eternally grateful! Or if what I’m trying to do isn’t feasible, I’d love to know that too. Thank you very much in advance for your help and expertise!
Hey there @mosquitofork! Generally the best (and only easy way) to get grooms to conform to the Skeletal Mesh they are attached to is to use the physical asset system (those pills you mentioned), what’s the limitation in the scene where this can’t be used? I might be able to determine a workaround.
Thank you for responding! For my particular scene, my character is an alembic geometry cache element and does not posses a skeleton, therefore I cannot rely on the pills for collision interactions. To be more specific, I would like for my characters hands or clothes to be able to collide with the groom. I am using a marketplace plugin (GeometryCacheCollision in Code Plugins - UE Marketplace) that generates a collision mesh based on the geometry that the alembic file possesses. I am fairly sure the plugin is working as intended, as when I check the “show collisions” box to see if they’re present, they’re glowing blue hue affirms me that the collision mesh is indeed there. To simplify the testing I spawned a simple sphere and generated a collision mesh, but that didn’t seem to work either. As for my specific scene, the physics isn’t totally necessary as both characters I have tested have short hair, but my fear is that later on down the line when I have to render a character with long hair that drapes over their shoulders, it will clip through their clothes or body.
I’ll definitely have to look a bit deeper to see how they extend their collision! It looks from their docs that it extends the physics system, so it should be possible, but without access to the plugin itself it’s mostly just conjecture on my part! I’ll see if I can find more complete information for you on this matter.
I have recently come across this video A little test of groom using Unreal Engine 5. - YouTube that showcases the exact effect I wish to replicate, so now I know it can indeed be accomplished. Now like most great findings there is no proper explanation as to how this effect was achieved, but at the very least I know it can be done, may the search continue forth!
I am currently still on the hunt for this sacred knowledge, and all has so far been for naught. However, seeing another example in a more recent version of the engine does instill hope, I’m sure the answer is close on the horizon
I actually reached out to the person that made this on twitter.
Here is his reply:
For physics sims and interactions you need to make sure the groom is the child of a skeletal mesh that has a physics asset. It’s the only way you’ll get any interactions with it. Hope that helps.
He also referred to a talk he did with Adobe and linked me this video:
This has certainly put things into perspective, and I now know that my desired effect is currently not possible. Thank you for the response, this was the illumination that I desired!
Getting other actors to collide with your groom actually IS possible, it’s just very poorly documented.
The trick is that you need to use the AddCollisionComponent(USkeletalMeshComponent* mesh) function on the UGroomComponent to add any meshes you want the groom to collide with.
Thanks go to Ryan Corniel for figuring out the solution:
