Practical experience in the physical animation and destruction of trees

Abstract

Much attention has been paid to generating realistic trees and plants as part of landscapes and scenery, but little attention has been paid to their realistic motion as part of the scene. This paper describes realistic animation of trees under varying conditions of wind and collisions. The intent is not to present rigorous analysis of trees, but rather to demonstrate how practical results can often be achieved in a production environment with radically simplified “physics”. Leaves, branches, and trunks of extremely complex trees have been animated, using a simplified physical model for the tree branches and leaves, and exciting them with a simulated turbulent wind field. Techniques are presented to minimize the computational cost. Techniques for realistic loss of leaves, breaking of branches, and uprooting of trees under high wind conditions are also presented.