# MESH DEVELOPABILITY

Some weeks ago I had an interesting conversation on the Houdini Discord Server about Keenan Cranes fairly new paper Developability of Triangle Meshes. The paper is, of course, excellent as always and the topic quite interesting in general. Nevertheless I somehow missed it when it was officially published and even worse – I completely forgot about it although I was at a conference around two years ago where Keenan Crane gave a beautiful talk about their new method. Fortunately there are people around who are really quick in finding new papers and after it was pointed out to me by Spinynormal I did a quick and dirty implementation in Houdini. It’s just a rather rough prototype without taking too much care about all the details but nonetheless it seems to work quite well.

To be honest, at the time when I saw Keenan Cranes talk I was first a bit sceptical. I really liked the idea and thought wow, that’s brilliant but I also had my doubts about the practicality of their method. Since the result depends largely on the structure of the mesh and not so much on it’s shape (or other properties), flipping some edges, for instance, might lead to a very different solution. And to put it simple, it wasn’t sure if this is an advantage or rather the opposite. Well, now, years later and after playing around a bit with the implementation in Houdini, I’m pretty much convinced that it’s an advantage. It’s quite interesting to watch how the mesh evolves into different shapes by just changing small parts of the triangulation. But then again, I don’t need to use it in practise.

K. Crane, O. Stein, E. Grinspun: Developability of Triangle Meshes

## 8 thoughts on “MESH DEVELOPABILITY”

1. Hello! (rewriting comment here because this post is more recent)
i´m developing a sort of muscle simulation framework on houdini, and creating some little tools for each step of geometry preparation before simulation. I’m trying to figure out how to create an attribute on input muscles to automatically create a muscle fiber directions to use this attribute to drive anisotropic muscle contraction on FEM simulation. (right now i’m doing this manually, but i with to proceduralize this step too!)

i have some ideas, as use medial axis to detect volume “flow” of muscles, but i had no idea how to implement… searching on technical stuff i eventually found your blog! Can you help me on this?

you can see some result of R&D on my vimeo: https://vimeo.com/285373573

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1. Hi,
sorry for the late reply but i didn’t check the blog for a long time.
I just had a look a your vimeo channel and it’s a very interesting R&D project you’re working on. Could you explain what you mean by “volume flow”?

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2. Hello Houdini Gubbins author 🙂

I would like to thank you for creating such an interesting blog.
And I would also like to ask if there is any other way I could contact you. I am very interested in the work you develop here and would really like to discuss a few things with you.

Hope to hear from you soon 🙂

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1. Hi David,
if you’re member of the Houdini Discord group you could just ping me (petz) and i’ll get back to you as soon as possible.

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3. James says:

Hi, thanks for your amazing blog!

I think I have managed to calculate the hinge energy for a mesh, and its gradient, as described in the paper. I was hoping you could tell me the best way to approach the energy minimisation for the mesh? Is it possible in a solver + VEX?

Thanks!

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4. kye shimizu says:

Hey, is it possible for you to show the HIP file for this? Thanks in advanced

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5. Ben says:

Hello, thanks heaps for sharing this wonderful information.

I wonder if you have a scene file for this. It would come in handy for some organic modelling I’m doing for a game project, but I’m not sure I can spend the time to implement it myself, or if I even have the technical know-how.

Thanks!

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1. vincent says:

Would be interested to know more as well of this implementation… Please

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