Simple 2D Waves With FFTs
The 2D wave equation can be solved by summing up an infinite number of sines and cosines. This can be approximated quite quickly by a finite number of sinusoids over a large discrete grid using Fast Fourier Transforms in order to produce water-like height fields.
In this short demo, I used Perlin noise to generate the initial waveform and a custom multithreaded FFT implementation. The colors in the video represent the complex phase at each grid point.