ω γ Xo Yo delay it
framerate

Use your fingers or mouse to control the model (hold shift key or use mouse wheel to zoom it). Canvas is matched to your browser window. 0 < Xo < 330,   0 < Yo < 220. The script makes 2 it iterations with the time steps Δt = 0.05 per frame. Set it = 1 and γ = 0 after you get a stationary pattern.
Resonances in 2D stadium. A CPU based simulation of the wave equation with time periodic perturbation
WebGL Demos     updated 5 August 2010