Water simulation is a big topic so this blog will show a few example of some of the techniques people use to make water in computer look like the real thing. First is product of a research: "Real-time Realistic Ocean Lighting using Seamless Transitions from
Geometry to BRDF" (E. Bruneton, F. Neyret, N. Holzschuch, Eurographics
2010) and FFT-based ocean synthesis method of "Simulating Ocean Water" (J. Tessendorf, Siggraph 2005.
For those of you who want to learn more about the math: