Скачать или смотреть A linear wave crossing an octagon with refractive index 2

In this variant of the video    • A linear wave crossing a hexagon with the ...   , the hexagon has been replaced by a octagon, and its refractive index is equal to 2, which occurs in certain crystals such as boron nitride.
The color hue depends on the wave height. The boundary conditions are absorbing on the right boundary, and periodic between the top and bottom boundary. The graph at the right shows the wave height near the right boundary of the simulation, slightly averaged over a moving time window.

Render time: 37 minutes 25 seconds
Compression: crf 23
Color scheme: Turbo, by Anton Mikhailov
https://gist.github.com/mikhailov-wor...

Music: "Sleep Music No. 1" by Chris Haugen‪@ChrisHaugenChannel‬

See also
https://images.math.cnrs.fr/des-ondes... for more explanations (in French) on a few previous simulations of wave equations.

The simulation solves the wave equation by discretization. The algorithm is adapted from the paper https://hplgit.github.io/fdm-book/doc...
C code: https://github.com/nilsberglund-orlea...
https://www.idpoisson.fr/berglund/sof...
Many thanks to Marco Mancini and Julian Kauth for helping me to accelerate my code!

#wave #refraction #prism #octagon