Bending and creasing virtual paper

We developed a mathematical model to simulate the bending and creasing behavior of paper-like sheets. This model permits interactive deformation of a surface remaining isometric to a plane rectangular sheet. It exhibits some important characteristics of paper behavior, such as the appearance of creases for some shapes of the boundary. Accurately simulating the detailed behavior of paper creases would involve several complex tasks, like employing mechanical shell modeling with possible boundary layer phenomena and studying the dynamics of buckling, or considering paper´s plasticity. We do not discuss these difficult problems, instead simply analyzing the creasing phenomenon as a transition between two kinds of applicable surfaces.<>