Synthesizing Waves from Animated Height Fields

• Published in: ACM transactions on graphics 2013, Vol.32 (1), p.1-9
• Main Authors: NIELSEN, Michael B, SÖDERSTRÖM, Andreas, BRIDSON, Robert
• Format: Article
• Language: English
• Subjects: Animated; Applied sciences; Artificial intelligence; Artists; Computer science; control theory; systems; Computer simulation; Dynamics of the ocean (upper and deep oceans); Earth, ocean, space; Exact sciences and technology; External geophysics; Flattening; Fluid dynamics; Fundamental areas of phenomenology (including applications); General theory; Mathematical analysis; Oceans; Pattern recognition. Digital image processing. Computational geometry; Physics; Physics of the oceans; Shot; Surface waves, tides and sea level. Seiches; Visual effects
• ISSN: 0730-0301; 1557-7368
• DOI: 10.1145/2421636.2421638

Computer animated ocean waves for feature films are typically carefully choreographed to match the vision of the director and to support the telling of the story. The rough shape of these waves is established in the previsualization (previs) stage, where artists use a variety of modeling tools with fast feedback to obtain the desired look. This poses a challenge to the effects artists who must subsequently match the locked-down look of the previs waves with high-quality simulated or synthesized waves, adding the detail necessary for the final shot. We propose a set of automated techniques for synthesizing Fourier-based ocean waves that match a previs input, allowing artists to quickly enhance the input wave animation with additional higher-frequency detail that moves consistently with the coarse waves, tweak the wave shapes to flatten troughs and sharpen peaks if desired (as is characteristic of deep water waves), and compute a physically reasonable velocity field of the water analytically. These properties are demonstrated with several examples, including a previs scene from a visual effects production environment.