Borealis
Karel’s piano flies you bodily into a receding tunnel of light — a single-take, never-repeating raymarched passage through luminous fog toward a growing white-gold core. Loud passages surge you forward; quiet ones let the light settle. Over the minutes the fog thins and the radiance widens.
tap Begin — sound and the passage into the light start together
Design notes
The question. What if Karel’s real piano flew you bodily INTO a receding volumetric tunnel of light — the way near-death survivors describe it?
How it works. A full-screen WebGL2 fragment shader raymarches ~64 steps through a volume of luminous fog. The camera translates forward along +z every frame, so the ring-structured walls stream past you — real perceived depth, not a pattern on a wall. The log-polar / form-constant engine (Klüver’s tunnel form constant, phi = 0) shapes the tunnel cross-section into concentric rings, warped along depth so they flow toward you as you fly in. A bright axial core grows and widens as you approach.
The piano drives it. An AnalyserNode reads the recording’s energy; loud passages surge your forward speed and brighten the core, quiet passages let the light settle. A Shepard endless-rising tone (the auditory analog of endless forward motion), a sustaining drone pad, and a cavernous convolution reverb place the piano in the tunnel. Over ~5–6 minutes the fog thins and the radiance whitens, so minute 5 ≠ minute 1.
References. Karolina Halatek, Terminal (a walk-through cylindrical LED light-tunnel built from near-death survivor testimony); Klüver’s tunnel/funnel form constant; the Bressloff–Cowan retino-cortical log map; Íñigo Quílez’s volumetric fog/raymarch technique.
Safety. Forward motion is smooth continuous translation, never a strobe. Any optional luminance pulse routes through the shared safe-flicker engine (≤3 Hz, soft floor, instant kill, off by default) and reduced motion is honored by slowing the passage.