Spiral Waves in Excitable Medium

This is for a university project... I post things like this, too! :D Notable moments of the video: 0:00 - Explicit solver with default settings (dt/eps smaller than 1) and perlin noise 0:57 - Lowering 1/epsilon until waves disappear to clear the simulation area 1:00 - Manually increasing "u" variable (drawing) 1:14 - Creating a double-spiral wave 1:47 - Adding periodic boundary condition 3:21 - Displaying U field only (wavefronts) 3:32 - Visualizing wave periods (note wave tips) 4:15 - Experimenting with 1/epsilon to change wave-tip movement 6:00 - Straight waves starting to form at low 1/epsilon 6:23 - Unexpected crash :D 6:25 - Increasing to delta time/epsilon to make numerical solution unstable 7:33 - Instability in single-point diagrams visible at dt/eps = 2 7:47 - Crashing at dt/eps = 2.5 7:58 - Increased instability at dt/eps = 2.2 8:25 - Crashing automatically at dt/eps = 2.3 8:48 - Semi implicit solution at dt/eps = 2.3 (no instability) 9:27 - Full simulation speed at low 1/epsilon (straight waves forming) 10:23 - Experiments with low 1/epsilon value 13:20 - Creating a truncated and stable straight wave