Towards believable cloth motion in computer animation

Abstract

This thesis covers the implementation of a cloth modeling algorithm within a computer animation package. The main objective of this thesis is to prove the feasibility of simulating the behavior of cloth using an empirically based model coupled with constraint dynamics and establish the groundwork for future studies into the use of cloth models in computer animation. To achieve a quick and accurate solution, two different forward dynamic constraint based system algorithms are studied and implemented. One approach, pioneered by Breen-DeVaul-House, computes the solution to the cloth equation by breaking up the cloth model into an acyclic length constraint system that may be solved in linear time with respect to the number of constraints. This approach is well suited for cloth models that collide only with force fiends, yet, is unacceptable for the proposed application. Therefore the Breen-DeVaul-House approach is modified to incorporate collision with polygonal objects. Even though the single matrix approach does not break up the cloth model and is slower in computing a solution for a dense mesh, this approach accurately calculates collisions between a mesh and a polygonal surface through the use of surface constraints and surface force dampers.