View Full Version : Any suggestions?

08 August 2008, 09:06 PM
Hi guys,

I need to rig up a tie and also some strands of modeled hair so that they can have some movement, and I was wondering if anybody as any suggestions about how to do this. I've been experimenting with soft body dynamics and motion dynamics, but once I add colliders they start to twitch and freak out.

I read Julez's tips about rigging it with bones, animating it, exporting mdd's, and then applying dynamics, but I'm not sure how that works. I get the process of exporting with mdd's, but how would you go about applying SBD to something already animating? Wouldn't that eliminate the point of SBD? Any explanation or other ideas?


08 August 2008, 11:35 PM
You can't animate the subtle movements by hand with bones?

08 August 2008, 12:20 AM
Yeah, I definitely could. I was just hoping to utilize dynamics to make the movement more natural and also make my life easier. But seeing as how the dynamic sims I've been setting up are causing so much ugliness, it looks like they'll make my life a lot harder.

08 August 2008, 03:03 AM
You can always apply dynamics to a few bones. If you also apply constraints to those bones it should give you a lot of control and allow you to save time animating.

08 August 2008, 03:51 AM
I would try a few bones and add dynamics to some bones... with a lite setting but only on group(s) of hair, not the whole thing.

Cosman DVDs would be in order.

08 August 2008, 04:09 AM
So when you say apply dynamics to bones, do mean with motion dynamics, or some other way?

And you suggest using constraints on the bones to simulate collisions?

(BTW, thanks for your guys input - I really appreciate the help!)

08 August 2008, 08:23 AM
Remember that the most predictable dynamics are those that aren't dynamic at all, but rather an expression to evaluate some delay, follow through and overlap. The basics for fake dynamics can be seen here in this example by mark wilson on the messiah wiki:

08 August 2008, 09:04 AM
Sorry for the thread jack but is the Messiah Wiki still going? Did a search went to this page: and format seems to have changed.

08 August 2008, 02:39 PM
Arf, that was just the other place I tried to put the wiki originally, but it was so cluttered that I changed to scribblewiki

08 August 2008, 07:25 AM
Would that fake dynamic expression work on multiple bones, like with a chain of bones for a tie?

Would there happen to be any tutorials describing the process of setting up that system?

08 August 2008, 08:12 AM
Would that fake dynamic expression work on multiple bones, like with a chain of bones for a tie?

Would there happen to be any tutorials describing the process of setting up that system?

There's no specific tie rigging tutorial, so you're going to go in there and get dirty if you want the expression solution. What this image teaches you though is the principle, it's practically a tutorial in itself.
If you for instance had several copies of this expression you could apply it gradually down a bone chain with an offset on the delay by increasing the point in time sampled.
So if you have the expression in the image for bone_1 and then for bone_2 you change the last part of the expression to for instance [Body_1:ywpos@NOW-([Belly_Control_Slider:ypos]*60)]
So by increasing the number, the delay will be longer for the second bone, and you will get a smoother and more natural motion, with overlap.

You need to learn and apply the principle shown here though, not just copy it out of the book. Otherwise you will end up with a tie that moves like a belly :)

Note that I think it's probably easiest to just stick a few bones in and animate the tie by hand. Unless you're going to make more than a couple of minutes of animation I don't think that perfecting a tie automation system will be rewarded in production time straight away compared to just animating it with bones. The expression method might be more rewarding in terms of learning more about messiah though.

Motion dynamics on bones might be enough for you too. It might be quicker to set up but less controllable:

08 August 2008, 04:35 PM
Thanks Ulven. I appreciate the advice.

The short the character is for will be about 6 minutes, and he's pretty much the exclusive focus of it, so that's why I wanted to set up a system for his tie and hair. But I also really need to get animating, go I might just set up bones and do it by hand.

I'm pretty new to messiah. I really like the expressions system, but I just haven't done much experimenting with it yet. Only a couple of quick things to add some custom controls to my rig.

I tried motion dynamics, and I liked the movement it gave, but I was having issues with the both collisions and the mesh itself. The tie kept twisting (full 180) randomly up and down its length whenever it moved, and I couldn't get it to stop. I even tried adding some internal structure to it to try to make it more solid, but that didn't work. That was with using curves for the motion dynamics though, not bones.

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