LC #42 Pipers Alley

View Full Version : softbody dynamics on enveloped mesh?

06-09-2008, 01:33 PM
Hi, I'm trying to use some softbody dynamics on an enveloped mesh, mainly to have some secondary animation in the ears (pointy ears). I have my character bend from side to side, but sofar it is not working, no softbody movement in the ears at all. The 'Use body animation' switch is set.

When I aply my softbody, it puts it above the envelop operator in the animation section in the stack. But then my mesh won't deform with the skeleton anymore. If I put the softbody operator (anywhere) below the envelop operator, there is no softbody movement at all, no matter what settings.

Is it possible to use softbody dynamics with an enveloped rig or should I take another route?

ps: the ears are weighted 100% to the head bone.

06-09-2008, 02:57 PM
Take another route...

I never could make it to work even if it says on the manual.

Your best option is to have another Object like a sphere having the SBodies and then use this Sphere to influence the Envelope.

Theres a script on the netview called 00AddNulltoPoints (something like this).

Install it (read the instructions) and it will let you select Points and add nulls to those Points, so if the Point moves the Nulls is Constrainted to it it moves also, now use this Nulls as Envelopers of your mesh.

Its mode work but at least it works.

In easy steps would be something like this:

- Add Sphere and parent it to some Bone and add the SBodies to it.

- Select the Sphere points (some or all of them as desired) and run the 00AddNullToPoints Script

- Nulls will appear CONSTRAINED to the Sphere Points

- Envelope the desired Mesh part to this NULLS


- Make new Chains and Contraint the Eff to these Nulls (as you prefer or looks more simple to you)

Hope it helps, if you are confused i'll try to put a simple example but not today.

06-09-2008, 03:16 PM
Hi Sil3, thanks for your reply. Too bad it doesn't work, could have been quite handy.
I understand what you meam by the sphere trick. I'll give it a try, thanks.

06-09-2008, 06:03 PM
or use Tails bones on the ears =)

you prolly have to re envelope them but will work =).

06-09-2008, 11:09 PM
Muchos gracias pelos, es un solucion muy grande :D

It is a realy clever and delicate solution and does perfectly what I want it to do :) Thanks!

06-10-2008, 01:28 AM
You could also use a set of constrained implicit objects with lowered blend weight to effect influence. If you want to keep them from coliding with the head, constrain them to the volume of another implicit.

Just a thought!

06-10-2008, 01:44 AM
Softbody and Envelope wiggle (FAQ)

06-10-2008, 12:22 PM
@ Mocaw: Yeah, I know that trick but I think it gives some wonky results, especialy with back-and-forth movement, since the constrained object won't follow the whole path traveled by the constrained-to object. Thanks for the heads-up though. :)

@tc: Yeah, that kinda works a bit. But when you remove the gravity, there won't be any deformation on the mesh by the softbody operator, while a normal softbody doesn't need the gravity to deform the mesh. But thanks for helping. :)

PS: @tc: Is this your harpy here on youtube? That is some impressive dynamics setup!
Harpy on youtube (polygonal nudity) (

06-10-2008, 02:50 PM
What you're trying to achieve can be done with softbodies, but is a pain in the butt workaround, as you can't apply directly to enveloped mesh.

I would say to just forget about what you're doing with Softbodies and go get this new script

It's a replacement tail spring op that works beautifully. I think the site is down at the moment. If you need it, PM me and I'll send it over to you.

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06-10-2008, 02:50 PM
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