Modeling waves and surf

ABSTRACT

Although modeling natural phenomena is recognized as one of the greatest challenges of computer graphics, relatively little time has been spent on modeling ocean waves. The model presented in this paper is suitable for the rendering and animation of waves approaching and breaking on a sloping beach. Waveforms consist of a phase function which correctly produces wave refraction and other depth effects, and a wave profile which changes according to wave steepness and water depth. Particle systems are used to model the spray produced by wave breaking and collisions with obstacles. A scanline algorithm for displaying the wave surface is presented, along with a method of integrating separately rendered particle systems with other surfaces. Hidden surface removal for both waves and particles is done using a novel variation of the A-buffer technique. Methods of implementing the model are presented and compared with previous rendering techniques.

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INDEX TERMS

Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.5 Computational Geometry and Object Modeling
          Subjects: Curve, surface, solid, and object representations
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Color, shading, shadowing, and texture

General Terms:
Algorithms