// LORENZ STORM — ribbons riding the genuine Lorenz attractor ODEs: the
// two-winged butterfly drawn by glowing trails. Pattern taught: the
// `field:` key swaps the ribbon engine's velocity field.
{
    name: "Lorenz Storm"
    engine: "ribbons"
    seed: 28
    field: "lorenz"

    ribbons: 40
    trail: 90
    width: 0.09
    flow_speed: 2.4
    bound: 6.0

    beat_pulse: "0.5 * (0.2 + 1.6*p0)"
    // PERFORMANCE DIALS — mid-knob = the stock look, exact.
    p0: 0.5  p1: 0.5  p2: 0.5
    dials: [
        {name: "PUMP", bind: "p0", default: 0.5},
        {name: "TRAIL", bind: "p1", default: 0.5},
        {name: "GLOW", bind: "p2", default: 0.5}
    ]

    color_bg: #x080410
    color_a: #xffaa44
    color_b: #xff4488
    color_c: #xffffff

    cam_dist: 12.0
    cam_orbit: 0.10
    fog: 0.02

    stages: [
        {kind: "feedback", amount: "min(0.75 + (p1-0.5)*0.44, 0.97)", zoom: 1.002, rotate: 0.0, dim: 0.93},
        {kind: "bloom", threshold: 0.4, strength: "1.4 * (0.25 + 1.5*p2)", 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 = trail age 0..1, attr = (ribbon, age, hue, side).
    // 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.DrawVjFxRibbon {
        fx_color: fn(t: float, attr: vec4, normal: vec3, wpos: vec3) -> vec4 {
            let hue = attr.z
            let base = self.col_a.mix(self.col_b, hue).mix(self.col_c, self.time_beat.w * 0.5)
            return base
        }
    }
}