Dynamic cutting for skeletal bones

Hi there,

I am a VFX artist for Half Sword Games, currently I am trying to figure out how to do Dynamic cutting for skeletal bones/meshes.

I have seen that Static Objects have no issue with Dynamic cutting in any direction.

For static meshes: https://www.youtube.com/watch?v=KSexcEOB2Is

Is there any way we can achieve it for skeletal meshes?

I have seen games like Shadow Warrior 2, Dead Island 2 and metal gear solid revengeance do it.

What do we need in order for this to work? Does it need to be done outside of the engine to achieve this or is it possible in engine?

Greetings,
Yosuf Nikchighamsari (GalaxyHighMarshal),
VFX Artist at Half Sword Games.

There is a plugin available that does this.

https://www.fab.com/listings/101770a6-eddd-47d2-ad8a-f6e0639caca6

It is not by default in the engine. You would have to code it yourself if you don’t want external plugins.

You could have the character cut up into specific parts (hands, arms, legs, torso, head) and stitch them together with the Leader pose component.

In theory for example upon a slice of the hand you could separate if from the leader pose component and enable physics on the skeletal mesh component detaching it from the mesh.

For anything more complex you would need to probably extend your own skeletal mesh class.

Also you would have to ask yourself the question if the skeletal mesh were to remain animated after the cut or would it turning to a static mesh be enough for your project (and then slicing it)

Here is a behind the scenes of how they did it in Dead Island 2

Hi 3dRaven!

Thank you for the response! I ll try this plugin, see it that would be the type we wanted.

I ll experiment with it!

I had another question, I dont know if I would have to make a new post for it.

If i wanna simulate, real time skin tearing with softbody and or to add soft body skin mesh cutting flaps physics.

What would be the best way to do this with Unreal Engine?

We have Render Target wounds setup to give dynamic damage per direction of weapon hits, but we wanna give it an extra visual feedback.
where the skin that is cut has movement like cut chaos cloth physics to it, while limbs that are hit have this softbody response with ability to be torn like in this youtube clip.

Is this possible with niagara or a plugin? what are the options?

Greeting!

I’m not sure if limbs can be detached through the disconnecting of bones at runtime. You could clone the limb and scale the bones or have spare parts that can be spawned in at the joints and scale down the severed limb to zero to hide it (through covering up remaining wounds would be tough).

Maybe someone has more knowledge on the matter. I’ve seen a couple of posts that mention solutions, but haven’t followed them. Perhaps the forum has a more indepth example somewhere.