We present a unified approach for geometric and physical modeling using implicit functions, for application to graphics and animation. This method extends previously proposed techniques, and allows the standard finite element method to be directly combined with geometric modeling, resulting in quick calculation of an object's mass and stiffness matrices, and its vibration modes and frequencies. Because the approach is based on an implicit function representation, it allows very fast collision detection and characterization. Examples of complex physical and geometric modeling are presented
A shorter and earlier version of this paper has appeared as ``A Unified Approach for Physical and Geometric Modeling for Graphics and Animation'', in Computer Graphics Forum, The International Journal of the Eurographics Association. 2(3), 1992, Editors: Alistar Kilgour and Lars Kjelldahl, Publisher: Blackwell, U.K.