// CONFETTI SWARM — the hard-techno flock: five hundred additive neon
// gliders, and a PREDATOR dives through the swarm on every bar so the
// whole formation detonates and re-forms in four beats. Pattern taught
// here: `predator` is the flock's bar-synced scatter (CPU-side boids, no
// binding needed), `additive: 1` flips the same engine from silhouettes
// to light streaks, and pulse-driven feedback smears the scatter into
// trails.
{
    name: "Confetti Swarm"
    engine: "flock"
    seed: 77

    birds: 500
    size: 0.11
    flight_speed: 3.4
    flap: 4.5
    bound: 6.0
    spacing: 0.34
    vision: 1.4
    goal_beats: 1
    predator: 0.85
    additive: 1.0
    bank: 1.6
    bar_beats: 4

    beat_pulse: "1.1 * (0.2 + 1.6*p1)"
    cam_orbit: 0.14
    fog: 0.05
    glow: "0.25 + 1.5*p2"

    // PERFORMANCE DIALS — mid-knob = the stock look, exact.
    p0: 0.5  p1: 0.5  p2: 0.5
    dials: [
        {name: "TRAIL", bind: "p0", default: 0.5},
        {name: "PUMP", bind: "p1", default: 0.5},
        {name: "GLOW", bind: "p2", default: 0.5}
    ]

    color_bg: #x06040c
    color_a: #x22ffcc
    color_b: #xff2f9a
    color_c: #xffffff

    stages: [
        {kind: "feedback", amount: "min(0.5 + 0.25 * pulse + (p0-0.5)*0.6, 0.97)", zoom: 1.015,
         rotate: 0.006, dim: 0.95},
        {kind: "bloom", threshold: 0.35, strength: 1.5, levels: 3}
    ]

    // 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 = speed 0..1, attr = (bird, speed01, hue, flap amplitude).
    // 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.DrawVjFxFlock {
        fx_color: fn(t: float, attr: vec4, normal: vec3, wpos: vec3) -> vec4 {
            let base = self.col_a.mix(self.col_b, attr.z)
            let gain = 0.5 + 0.6 * t + self.time_beat.w * 0.35
            return vec4(base.xyz * gain, 1.0)
        }
    }
}