Playground · Wave Interference
Wave interference
Two ripple sources, overlapping. Where crests meet crests the wave doubles (constructive); where a crest meets a trough they cancel (destructive) — carving out the fan of quiet lines you see here. It's the very same physics behind the double-slit fringes.
Drag either source to move it.
How it's built
Each source emits a circular wave sin(kr − ωt) that fades with distance;
the height at every pixel is just the sum of the two — that's the
superposition principle. Add them and you get bright bands where they're in phase and
dark nodal lines where they're exactly out of phase. Computed per-pixel each frame in
vanilla JS on a <canvas>. Shrink the wavelength or widen the sources and the fringes
bunch closer — the same relationship that sets the fringe spacing in the double-slit experiment.