Moving hairs without PsysX

Hi all!
I’m trying to figure out how to move the hairs of our femal character.
We have this 7k tris hairs mesh. Hairs seems to be too complex for a fast PsysX.
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So I’m wondering about another solution.
Once, using Unity, I skinned some parts of the hairs to some bones and then simply maked them move.
Is there some way to have a soft, light movement of the long strands at least without NVidia PsysX?

You could do morph target animation. Very fast but no physics is possible.

You could simulate it by animating it depending on movement and it would look fine.

You could also skin it to some bones and could even physically simulate those bones but that would be coarser and slower.

Beside bones and animations, you could try to create the effect with a material setup. Just add some vertex colours to the hair (so that the part at the head is fixed) and then move the material with some panner and sine nodes. After you have made the basic movement you can even add some parameters to that you get the right reaction from the movement :slight_smile:

I would just put some bones on it and set them up with some physics bodies in PhAT. Then all you have to do is set them to be 100% physics movement in the animation blueprint. You could probably get away with just two bones for the long strand, or one there and one on the lock at the forehead.

Hi!
I figured out to try with PhAT like suggested by all of you… I just have to find the proper number of bones in order to keep the ragdoll simple and fast (I have heavy performance requirements).
About the vertex shader sounds a nice idea… but I should simulate in some way the movement, so I suppose I need to calculate the offset in a blueprint and then apply the values to the material… It sounds complex :slight_smile:

Make sure to post the result -> never saw any good hair movement in the UE4 so would be cool if you could post your result :slight_smile:

I’ll try to do something good! :slight_smile:
At the moment the phat solution seems to work… I have some problems with collisions.
By the way I’ll move just the two strands… :wink: