An accurate model of wave refraction over shallow water

A computer model of wave refraction is desirable, in the context of landscape modeling. to generate the familiar wave patterns seen near coastlines. In this article, we present a new method for the calculation of shallow water wave refraction. The method resorts to Fermat's principle of the shortest path and computes the propagation of wavefronts over an arbitrary inhomogeneous medium. The propagation of wavefronts produces a phase map for each terrain. This phase map is then coupled with a geometric model of waves to generate a heightfield representation of the sea surface. The method is accurate and provides realistic wave refraction effects. The degree of accuracy provided by this method has enabled us to identify two other wave transport mechanisms. namely diffraction and caustics, for which no solution yet exists in the computer graphics literature. Our method does not attempt, at present, to solve these transport mechanisms. (C) 2002 Elsevier Science Ltd. All rights reserved.