Sphere:

“Cylsphere”:

Hollow cube:

These are animations that I and Joseph Perenia made with our first elastic deformation simulation program, which we wrote from the ground up using C++. It uses a finite-element method to compute stresses throughout the simulated object. Thence it computes forces to apply to the vertices of the mesh in order to move them into position for the next frame. Each video shows a simulation of progressively stiffer elastic material.