3DS Max - Jiggle (sp?) Physics with Bones

Ace-Angel

Hey to all,

I was wondering if anyone had any advice on what is the best way to set a jiggle physic setup with bones in 3DS Max.

I'm not sure if the correct terms is jiggle physics? I'm referring to the bounce, squash, stretch and 'fatty' movement of stuff like like skin (and lesser degree) hair or soft objects.

Example: I have a fat character, I have them rigged to run, I also have several strategic bones places over bigger fat surfaces to jiggle them manually since I don't trust automated solutions too much on my PC.

I read up that flex would be useful in this case, but I'm not sure how well it plays with bones.

I also read about 'spring' bones, but am unable to find too much information about how it would work in Max or how to set it up.

Oh, also, what about Morph targets? Are those utilized too over the body of a mesh, or would they rather be limited to facial animation in small places, since the performance cost is quite heavy.

Cheers in advance!

EDIT: Just to make it clear, I want to find a way to essentially 'bake' the physics of a bone into my keyframes, and then manually change them around, just like traditional animation. Not sure, if I'm making sense.

Mark Dygert

It's a "spring controller" that gets assigned to a bone.
Main toolbar > Graph Editors > Curve Editor > Select a track in the Track View hierarchy.
Track View menu bar > Controller menu > Assign > Spring
http://download.autodesk.com/us/3dsmax/2012help/index.html?url=files/GUID-B7D0424E-6DCB-44D9-AD0B-85B9A1EE3F5-0.htm,topicNumber=d28e3788

You can also assign a "flex modifier" to the model to get some jiggle, it can play over the top of skin so it inherits the motion from the bones.

If you need a bone only process, like for most games, you can "attachment constrain" a point to the surface of the jiggle mesh and then align and key a bone to that point and skin your final mesh to that bone. Jim Jagger as a "Animated Align" script in his JJ tools that really helps out with that kind of thing.

You can unlock the scale of a bone by selecting it, going to Animation > Bone Tools > uncheck refreeze length. You can also set it to squash if you want that.

Ace-Angel

Heya Mark!

Thanks for the quick post, mind if I ask some followup questions, or maybe you could point me in some resources to learn this stuff correctly (EI: Working with Morhph, Bone and Bakes)? I'm not really an animator incase you couldn't tell :P

Mark Dygert wrote: »

It's a "spring controller" that gets assigned to a bone.
Main toolbar > Graph Editors > Curve Editor > Select a track in the Track View hierarchy.
Track View menu bar > Controller menu > Assign > Spring
http://download.autodesk.com/us/3dsmax/2012help/index.html?url=files/GUID-B7D0424E-6DCB-44D9-AD0B-85B9A1EE3F5-0.htm,topicNumber=d28e3788

Is the Spring Controller limited to anything in particular? Or is a generic attribute (EI: If I use a Biped/CAT, etc as my base bone system, am I locked out of Spring?).

You can also assign a "flex modifier" to the model to get some jiggle, it can play over the top of skin so it inherits the motion from the bones.

Nice! I didn't know that, cheers!

If you need a bone only process, like for most games, you can "attachment constrain" a point to the surface of the jiggle mesh and then align and key a bone to that point and skin your final mesh to that bone. Jim Jagger as a "Animated Align" script in his JJ tools that really helps out with that kind of thing.

Ugh, sorry, but this part flew over my head

You can unlock the scale of a bone by selecting it, going to Animation > Bone Tools > uncheck refreeze length. You can also set it to squash if you want that.[/QUOTE
Ah, gotcha, that should be easy enough.

Cheers!