Point cache animated characters not following a surface!

[panthon]

Hello!

I have been struggling with a problem I am facing lately. I have built a collection of walking animated characters which come from biped skeletons. I animate them, pick the mesh, apply a point cache operator to it and store the animation. Then i delete the skeleton because i no longer need it.


Once this is done, im free to place the characters wherever i want, without worrying about merging all the skeleton, which is heavy for more than 10 characters.


The thing is that is very difficult to make them follow a bumpy or whatever non-flat surface, because the pivot is left behind at the first frame no matter what, so animating the rotation each 10 frames, for example, doesn't work.

Here you find an illustrated example:



I have tried Particle flow with no success. I have looked for a script to stick the pivot point to the mesh, kind of animating the pivot point....no success either...The character keeps on intersecting the ground...

Any ideas?

[vance3d]

I think to do what you want you have to animate the characters doing a walk cycle which basically animates them in place. that way the pivot is always centered on the character, it doesn't walk away from it. then you can use particle flow to have them follow a surface.

V Miller

[panthon]

I think to do what you want you have to animate the characters doing a walk cycle which basically animates them in place. that way the pivot is always centered on the character, it doesn't walk away from it. then you can use particle flow to have them follow a surface.

V Miller

That is an interesting approach, I will try it.
There are some considerations with PF, regarding the particle speed, to match the step size to the translation speed. Not all characters should move at the same speed, some should avoid collisions...that's another story...

I usually work with motion capture files, sometimes modified with the Non linear editor bundled with character studio, do you think it is possible to get all the motion from mocap file except the translation? I will look into it...
The problem now is all my library seems to be useless, unless u need them for flat terrains...

[dellis]

If i'm reading this correctly all you have to do is figure out the total distance traveled by the character, draw a spline the same distance, drop it to the surface and then make a dummy and attach the character to the dummy....then the dummy to the path with follow on. might look weird depending on the topology of the ground though.

Actually, now that i'm thinking about it you could probably wire the characters Z to the Z of the dummy following the path....that way you wouldn't have to link the character to the dummy...

[panthon]

If i'm reading this correctly all you have to do is figure out the total distance traveled by the character, draw a spline the same distance, drop it to the surface and then make a dummy and attach the character to the dummy....then the dummy to the path with follow on. might look weird depending on the topology of the ground though.

Actually, now that i'm thinking about it you could probably wire the characters Z to the Z of the dummy following the path....that way you wouldn't have to link the character to the dummy...

If you attach the character to a dummy, it will be correct in the first frame, but after that, the attachment takes into account the pivot point position, because it thinks the character is in the same place as the pivot. This leads to increasing offset and it is not avoidable. Wiring gives us the same result, it will probably wire the pivot point correctly, but the character is getting away from it, so the errors are increasingly evident.

[studioDIM]

blind guess: putting an xform on top of your pointcache at frame 0 (rest pose, or first frame) doesn't help it?

Lele