# Ho do you make mesh vertice restrictions for deformation like origami?

Before I had a Blender artist making a digital animation of my work on the ONAK canoes (an origami boat), but now I’m working on a different project and I started to learn Blender for myself to do this.

I’m staying with origami techniques. Here my question:

When I design a mesh that makes the origami pattern of my design, and then pair it to an armature, It would come handy if connected vertices in the Mesh would not be able to change distance from each-other. Is it possible to add such a restriction with some code/plug-in, and does such a code already exist?

I expect great use for such a function in the Origami engineering community. This would make animations like this much more easy: https://www.youtube.com/watch?v=4YvCuyH6x4o

Most sincerely,

Otto

Or: could I add a bone to all vertice-connections, and then make restrictions to the bones? Problem is that I get parent-loop problems all the time…

When you’re deforming with an armature, the distance between verts is entirely a function of your armature, how you use it, and your weights.

If you rotate a bone, any verts fully weighted to that bone will maintain their distance to the head of that bone and from each other. If the head of that bone is at the position of a vertex, then all those vertices will be maintaining their distance to that vertex.

If you want to maintain the distance between a rotating vert and two verts-- a line-- then the bone’s head needs to be on that line, and it can only rotate in the axis of that line. Preventing other rotation can be achieved by setting the local axes of the bone appropriately (through tail placement and bone roll) and the use of transform locks.

If you want to maintain the distance between a rotating vert and three, non-colinear verts – a plane-- then it can’t really be done. All you can do that maintains distance is mirror across the plane.

However, if you want to think about other things, consider that the essence of soft body physics is maintaining edge lengths-- that is, maintaining the distance between verts. If you give something soft body physics (probably with gravity + collision disabled), then you can deform them any way you want and the soft body physics will try to “fix” what you did to break it.

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Thank you @Bandages… I’ll to experiment a little more with what you’re telling here. Think it would solve my problem now.

I anyhow believe it would be interesting to have a plug-in to maybe automatically make a rig fit for a certain Mesh and then maybe have some soft-body physics applied to it if this works. I’m quite new to Blender. How do I best request for such kind of plug-in?

Well, I don’t think it’s a great idea for an addon, personally. I think that as you get more experience, particularly with armatures, all of that will just come naturally to you. (And any addon wouldn’t really be able to solve the problems, it would just be a different interface for asking you to solve the problem.)

In general, I don’t think you’re going to have any luck requesting addons. Addon developers aren’t any more interested in making your addon for you than modellers are in making your model for you. Unless you’re willing to pay, right?

If you’re willing to pay, I believe this board has a commissions section. Looks like sections for paid work and volunteer work both, if you disagree with me and think that somebody else would want to do this for free.