🧪 Aurora Lake Reflection (2D)

This 2D companion keeps the same optical idea as the 3D Aurora Lake Reflection — light from the aurora borealis mirrored on a still lake — but builds it from plain Canvas2D math instead of a WebGL scene graph. Each aurora ribbon is the sum of two travelling sine waves at different wavenumbers and speeds (a real wave-superposition model, the same principle behind beating and interference patterns), and the reflection is not a static vertical flip: the upper scene is rendered once into an off-screen buffer, then copied into the lake row by row with a per-row horizontal offset driven by a third sine term, so the mirror image visibly ripples the way a real water surface would. Five sliders — wave speed, aurora intensity, ripple strength, band count and hue shift — let you push the system from a glassy, near-perfect mirror to a choppy, fast-moving one, while a live readout reports the primary band's wavelength, amplitude and current ripple offset in pixels.