d8d5ea8b6a
Restore missing required asset/flow packages from the pinned nigig revision; retain upstream script isolation, X11 hover, and widget-core fixes. Validated makepad-widgets data feature with Rust 1.97.1.
99 lines
4 KiB
Text
99 lines
4 KiB
Text
// FRACTAL DESCENT — a kaleidoscopic-IFS fractal orbited in the dark, its
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// fold angle WANDERING with the beat count so the shape never repeats.
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// Pattern taught: an iterated fold (abs + rotate + scale-out) inside a
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// scene_sdf subclass — five iterations, own constants; the marcher, AO and
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// palette all come free from the base shader. `p0` binds extra fold angle.
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//
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// THE LAW THIS DOCUMENT LEARNED THE HARD WAY: a shader that is a function
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// of `beat` must be a BOUNDED one. `beat` is the host's SONG clock, not a
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// stopwatch that starts when the effect loads — cue this into a deck an
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// hour into a set and the first frame is at beat 6000. The original fold
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// angle was `0.52 + beat * 0.010`, an unbounded creep: lovely for the ten
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// seconds a gallery grab ever sees, and by beat ~120 the IFS attractor has
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// escaped the marcher and the deck shows BLACK. So the wander here is two
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// slow sines with an irrational-ish frequency ratio (quasi-periodic — it
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// still never repeats) clamped into the band where the attractor is a
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// picture, and the FOLD dial is centred on 0.5 so no knob can leave it.
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{
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name: "Fractal Descent"
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engine: "raymarch"
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steps: 84
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max_dist: 30.0
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cam: "orbit"
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cam_speed: 0.14
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cam_dist: 3.6
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cam_height: 1.0
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cam_fov: 62.0
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shadow: 1
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beat_pulse: "0.6 * (0.2 + 1.6*p2)"
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beat_rate: 1.0
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fog: 0.05
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glow: "1.45 * (0.25 + 1.5*p1)"
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// FOLD is knob-shaped: 0.5 is neutral, the binding breathes around it
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// over the bar, and the scene reads it as an OFFSET from centre.
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p0: "0.5 + 0.16 * sin(bar * tau)"
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// PERFORMANCE DIALS — FOLD is this doc's own p0 lever (the scene hook
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// reads self.user.x; touching it holds the fold open); GLOW and PUMP
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// route p1/p2. Mid-knob = the stock look, exact.
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p1: 0.5 p2: 0.5
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dials: [
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{name: "FOLD", bind: "p0", default: 0.5},
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{name: "GLOW", bind: "p1", default: 0.5},
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{name: "PUMP", bind: "p2", default: 0.5}
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]
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color_bg: #x05040f
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color_a: #x8f4dff
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color_b: #x0fd0c8
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color_c: #xf0eaff
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stages: [
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{kind: "bloom", threshold: 0.5, strength: 1.35, levels: 3}
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]
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shader: draw.DrawVjFxRaymarch {
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scene_sdf: fn(p: vec3) -> vec2 {
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// Kaleidoscopic IFS: fold into the positive octant, then TWO
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// rotations (xz and yz — the second is what lifts the fractal
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// out of a flat extrusion), scale outward. Own constants.
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let mut z = p * 0.72
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let k = 1.84
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let off = vec3(1.18, 0.62, 1.34)
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// The fold angle WANDERS but never escapes: two slow sines of
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// the beat count (periods ~153 and ~370 beats, ratio not a
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// simple fraction, so the pair never quite comes back around)
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// plus the FOLD dial as a signed offset from mid-knob. The
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// clamp is the guarantee — outside roughly 0.2..0.9 the
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// attractor either collapses or runs off past `max_dist`, and
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// the picture goes black.
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let b = self.time_beat.y
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let wander = 0.14 * sin(b * 0.041) + 0.08 * sin(b * 0.017 + 2.3)
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let fold = (self.user.x - 0.5) * 0.24
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let ang = clamp(0.54 + wander + fold, 0.20, 0.90)
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let mut s = 0.72
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let mut trap = 10.0
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let mut i = 0.0
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loop {
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if i > 5.5 {
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break
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}
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z = abs(z)
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let r = self.rot2(vec2(z.x, z.z), ang)
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z = vec3(r.x, z.y, r.y)
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let r2 = self.rot2(vec2(z.y, z.z), 0.61 - ang * 0.35)
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z = vec3(z.x, r2.x, r2.y)
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z = z * k - off * (k - 1.0)
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s = s * k
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// Orbit trap: nearest approach to the origin, in world
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// scale — the palette rides the fractal's onion layers.
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trap = min(trap, length(z) / s)
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i = i + 1.0
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}
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let d = self.sd_box(z, vec3(0.90, 0.90, 0.90)) / s
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return vec2(d * 0.82, fract(trap * 2.6))
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}
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}
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}
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