MBR model (modified Beeler-Reuter).
2D spiral waves (WebGL 2)
"the BR model (mod = 1) produces breakup because it has a
very long wave length and adapts to very short at high frequencies and
leads to breakup via slow recovery fronts (the wave back is slow and the
wave front is too fast and crashes on it). By speeding up the calcium
dynamics by two (mod = 2) we can decrease the wave length
and avoid breakup." Flavio H. Fenton
On 2D plane Vm values are displayed by the red color.
2 x values are displayed by the green color.
This script uses simple explicit algorithm and 512x512
float32 textures with the CLAMP_TO_EDGE boundary conditions.
It makes 2 it time steps per frame.
Experimental WebGL 2.
The script uses multiple rendering into 2 textures (8 variables) and is more
clear and faster than WebGL 1 based one.