Mass-Spring system

[kelmer]

Hi, I'm trying to implement a mass-spring system over a 3D model, but I'm having problems on determining which vertices are the neighbors of each other; particularly, I would like to determine which vertices on the mesh are the bending, structural and shearing neighbors of each vertex, as shown in this image:



I want to do it programmatically (is this a real word??), in the sense that I can load any obj file and convert it into a mass-spring system without the user input on which vertex are neighbors of each. The problem is that the vertices are scattered on the obj file with no particular order and there is no way to "know" which ones are neighbors, apart from structural neighbours which are specified in the faces information.

Thanks in advance