// SERPENT STROBE — hard techno dominoes: two thousand black tiles on a
// boustrophedon serpentine, sixteen per beat, neon pips flaring white-hot
// at the impact front. Pattern taught: `resurrect: 0` = the front is a
// SAW — when the run completes, every tile snaps upright at once (the
// hard reset IS the drop); high jitter roughs the ranks up.
{
    name: "Serpent Strobe"
    engine: "domino"
    seed: 9

    layout: "serpent"
    count: 2000
    per_beat: 16
    spacing: 0.26
    resurrect: 0            // saw front: full-run snap reset
    pause_beats: 0
    flash: 2.5
    jitter: 0.30

    beat_pulse: 0.9
    p1: "0.8 * pulse"
    p2: 0.8

    // PERFORMANCE DIALS — the engine's own p-levers; touching FLASH
    // overrides the pulse binding above with a held gain.
    dials: [
        {name: "NUDGE", bind: "p0", default: 0.0},
        {name: "FLASH", bind: "p1", default: 0.5},
        {name: "ANTIC", bind: "p2", default: 0.8}
    ]

    color_bg: #x030308
    color_a: #x323a4e
    color_b: #x48586c
    color_c: #x40f0ff

    cam_orbit: 0.12
    fog: 0.010
    glow: 1.4

    stages: [
        {kind: "bloom", threshold: 0.3, strength: 2.0, levels: 3},
        {kind: "feedback", amount: 0.35, zoom: 1.003, rotate: 0.0, dim: 0.92}
    ]

    // THE LOOK LIVES HERE. This block is not a reference to the
    // engine's shader — it IS the pixel math this effect runs.
    // Rewrite it and the effect looks different; everything else
    // (geometry, motion, the content coupling, the beat) keeps
    // working, because the block SUBCLASSES the engine shader.
    // Inputs: t = topple ease 0..1, attr = (branch, arc index, tile hash, yaw).
    // Signals: self.time_beat (time, beat, phase, pulse),
    // self.sig (bar, bpm, energy, dt), self.user (p0..p3),
    // self.col_a/b/c/bg, self.fog (density, glow, content, -).
    shader: draw.DrawVjFxDomino {
        fx_color: fn(t: float, attr: vec4, normal: vec3, wpos: vec3) -> vec4 {
            let mix_t = clamp(attr.x * 0.23 + attr.z * 0.12, 0.0, 1.0)
            return self.col_a.mix(self.col_b, mix_t)
        }
    }
}