🌊3D Waves in GeoGebra (numerical simulation)

In this short video I demonstrate the numerical solution of the wave equation on a structured grid in GeoGebra and visualize it using a moving surface in 3D view. The solution could be given analitically on a rectangular domain, but I wanted to demonstrate the use of numerical methods in GeoGebra. No javascript was used for creating this simulation. About the simulation: The laplace operator was discretised using the five-point finite difference stencil, and the semi-implicit Euler method was used for time evolution. Instead of discretising the second time derivative directly, I created a "speed" (u dot) scalar field, transforming the second order PDE to a first order one for (u, u dot). As the method is explicit, I had to limit the timestep size according to the CFL (Courant–Friedrichs–Lewy) condition, to avoid the solution blowing up.