In UE5 Physics Asset character’s skeleton is stretching if high enough force applied. Here how it looks on standard mannequins from 3rd person template project:
Is this a bug, or some kind of a new feature?
How can I turn it off, if I don’t want my character to stretch?
did you find the solution to this? I’m not able to test the rotation constrains as the character is behaving as jelly
Greetings Chosen_One and dorusoftware, thank you for posting your query to the forums.
Your concern sounds like you may need to add some constraints to your physics asset. If you do not already have constraints set up in your physics asset, I would see if adding them helps a bit.
I have found a YouTube video that goes over how to set up constraints, limits and much more if you are interested.
WARNING: This is an external link and as the end user, you are responsible should something happen to your device when you choose to click a link or follow steps that are not endorsed by Epic.
I hope this helps.
Hi Polite_Muon. In my examples it’s not my physics assets. It’s standard Epic’s mannequins. They have proper constraints.
Limbs are stretching under high enough force even if translation constraints are locked. And problem is that in UE5 this “high enough” force became not really high, comparing to UE4.
Hi dorusoftware! No proper solution yet. What I found is that in UE4 this limbs are also stretching if high enough force applied. But in UE5 force needed for this is about 10 times lower, or may be 100 times lower (didn’t measured it properly).
Still not sure if it is a just a bug, or some compromise solution for physics stability in-game.
To test rotations I suggest to use no-gravity mode in physics asset editor and push character’s limbs just lightly so they won’t stretch.
so i’ve got to understand this physic body thing a bit better and the stretch I was talking about appears because one needs to select a higher bone as fixed when testing.
I’m having a similar issue however there are some things that need to be stated/understood. When you are simulating like this and have bodies set to either not simulate or be locked (set to kinematic) they are immovable, and the mass is infinite (no amount of force will move them). Your mouse, is infinitely mass(less) and has an infinite amount of pull when you click and drag. So the objects you are pulling are pretty much linked to an immovable object and an unstoppable force.
If you were to simulate the entire object, odds are that the object wouldn’t stretch like what you see. However the issue I’ve seen is when someone grabs a character and drags them in a click and drag scenario on objects that have dangly bits, those things yo-yo like crazy because of the same problem, it’s an infinite amount of force being applied and I have yet to find anything that tells the physics constraint that it is absolutely immovable or unbreakable (even for the tiniest of frames). Oh and setting the breakable settings to some astronomical number doesn’t help either.
Setting up Substep kinda helps this, but I’m just getting used to that and haven’t seen how this affects framerate across a multiplayer platform.
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Hi! Good point about an immovable object and an unstoppable force. However, in practice fully simulated character starts stretching when just hanged by the limb. Forces are not so high in that case.
But sub-stepping option you mentioned really helps! I’ll mark this as a solution. Thank you Rasonage!
Still curious why all works fine by default in UE4, but not in UE5 though…