Editing Physics engine (section)

==== Soft-body dynamics ====
An alternative to using bounding box-based rigid body physics systems is to use a [[finite element]]-based system. In such a system, a 3-dimensional, volumetric [[tessellation]] is created of the 3D object. The tessellation results in a number of finite elements which represent aspects of the object's physical properties such as toughness, plasticity, and volume preservation. Once constructed, the finite elements are used by a [[solver]] to model the stress within the 3D object. The stress can be used to drive fracture, deformation and other physical effects with a high degree of realism and uniqueness. As the number of modeled elements is increased, the engine's ability to model physical behavior increases. The visual representation of the 3D object is altered by the finite element system through the use of a [[deformation shader]] run on the CPU or GPU. Finite Element-based systems had been impractical for use in games due to the performance overhead and the lack of tools to create finite element representations out of 3D art objects. With higher performance processors and tools to rapidly create the volumetric tessellations, real-time finite element systems began to be used in games, beginning with ''[[Star Wars: The Force Unleashed]]'' that used [[Digital Molecular Matter]] for the deformation and destruction effects of wood, steel, flesh and plants using an algorithm developed by Dr. James O'Brien as a part of his PhD thesis.<ref>{{cite web|url=http://graphics.eecs.berkeley.edu/site_root/papers/Obrien-GMA-1999-08/ |title=Graphical Modeling and Animation of Brittle Fracture|publisher=Graphics.eecs.berkeley.edu|access-date=2012-09-01}}</ref>