Letter grid v2 — Extrude
The letter sea lies flat on the ground and the reading head pulls true extrusions up out of it — lit, casting letter-shaped shadows — as the word is spelled in 3D.
Same infinite virtual grid + word-path + reading-head camera as v1 (shared via ../_grid.js), but rendered as a 3D scene. The whole sea of letters lies flat on the ground, and the letter(s) under the reading head RISE out of it — a true extrusion of the glyph outline (cap + walls), lit by a movable light and casting a LETTER-SHAPED shadow back onto the terrain.
Flat and raised letters share ONE glyph-geometry path (the flat ones are just a cap on the ground), so they always agree in orientation and position. How many cells rise is a continuous ELEVATION field — a multiplier + a spread: spread→0 raises only the centred letter, larger spreads reach its neighbours then cells further out, shaped by a falloff easing.
Everything is a pure function of animation.progression → seamless loop, and the camera/light never use orbitControl or per-frame randomness → recording-safe.
