Faking hair/cloth physics using vertex animation

[Abeysaurus]

@Chosker;684359

implementing this purely using WPO will give you a hard time.
for one your hair will not collide with the body, so you’ll see the hair going through the head and shoulders. you’d need to fake the collisions somehow.
second is the fact that to add some kind of drag/inertia from the player movement, you have to inject it manually because the shader doesn’t store the position of the previous frame. injecting the player’s velocity as a vector param would give you a start into that (you push the vertices into the opposite position), but you’d need to add some sort of blending that will make that push stronger on the longer parts of the hair and not affect those parts close to head.
then of course injecting only the player’s velocity would make the effect too uniform so you’d need some other method to add secondary animation (i.e. inertia and rebounds), so it doesnt just look like a solid piece of wood

usually for limiting hardware like mobile the common way is to just animate the hair using bones, and on somewhat more forgiving hardware driving it with rigidbodies (PhAT, not Apex) can be made to work. but I’ve always been curious if a WPO approach would look good enough if some effort is put into it. So I’m looking forward to what you can come up with

Thanks for that. I had similar ideas for the effect. I’m still working on the final character mesh so once i’m done, ill try them out and share the results. I was thinking i could use the vector param to offset direction of the hair based on the character movement and direction. Maybe could also use VInterp to get a smooth transition with the transition time hooked up to speed. Lot to fiddle around with. Will update as I go. Also, collision would be an issue, but im working on shorter hair, so should be fine. Additionally, I could also control the hair displacement with the vertex color too.

So far all i managed to do was just increase the wind intensity as the character moves… which actually looks rather believable, but would be cool of we could see a few strands fly up as the character falls, etc. It’s all in the fine details