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View Full Version : Collision between two soft bodies.


Oglok
04-19-2004, 01:31 PM
Hi

I'm trying to make 2 "bags" colliding, they are like that :

http://berserk016.free.fr/bag.jpg

They will start in this position :

http://berserk016.free.fr/bag2.jpg

And they will rotate to finish like that :

http://berserk016.free.fr/bag3.jpg

But when I create the soft bodies (duplicate and make copy soft, non soft as a goal), and use Make Collide, they do not collide, they still interpenetrate.

One bag with a wall, it works, but not between 2 softbodies.
Is there a solution or do I have to forget the dynamics and animate with bones and blendshapes.
The "bags" are dummies for an hair style "anglaises", si it has to move very smoothly with the head.

Thank you very much.

Bye

anthonymcgrath
04-21-2004, 01:28 PM
you could add springs to create tension in the bags and play with the settings but to be honest I'm an avid fan of keyframing or blendshaping most stuff hehehe!

alexx
04-21-2004, 03:16 PM
i never really ran into that problem exactely but i remember having tried to have a soft bodies geometry being a collision object for particles and had to see that it does not seem to work like that.

there is a small workaround which i have not thought to the end which should work and lets you get a collision.
(btw.. the basic idea with the connection editor is from a co-worker here):

you need a new object, that defrorms and behaves like your softbody, which is a normal object and not soft to have the collisions:

- create your softbody
- create a polyCube
- open the connection editor and bring the softbodys object shape to the left side and the cubes shape to the right side.
- connect outMesh->inMesh
- parent the resulting polyCube under your softbody (with preserve position OFF)
- now you can assign the collisions to the new and grouped deformed polyCube object.

cheers

alexx

jerome_sun
04-22-2004, 07:11 AM
good guy!:bounce:

thematt
04-22-2004, 01:26 PM
that's an awesome tricks..alexx really, :applause: thanks for that one never thought of that..

But one question I think he'd like his bag to collide to each other and then deform accordigly to the collision so how would that bag with the "collision bag" pluged would deform right since its deformations comes from the softbody that doesn't receceive collision himself..don't know if I'm clear.

anyway wouldn't it be possible to set up a radial fiels on a per particule to fake the particule collisions with some spring so the bags keep constistency.
i know that could be tricky but just in case you might wanna try that too (in case Alexx tricks doesn't do it as expected).

cheers

Oglok
04-22-2004, 02:26 PM
thank you for your replies, i'll use another trick, very close to alexx's one. I have 3 "bags" o i'll animate and deform by hand the middle one and make the 2 others collide with it.

I'm only a student and so not very used to all the possibilites brought by the connection editor, and all the tricks.

thank you again

bye

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