pakt27

See /software/p5js/pakt-februari/pakt27/ for a JavaScript version and /software/supercollider/februari-pakt/pakt27/ for accompanying sound code.

use nannou::prelude::*;

const N: u16 = 80;

fn main() {
  nannou::sketch(view).size(640, 480).run();
}

fn view(app: &App, frame: Frame) {
  let draw = app.draw();
  let win = app.window_rect();

  let index = app.time * 60.0;

  if frame.nth() == 0 {
    frame.clear(BLACK);
  } else {
    draw.rect().wh(win.wh()).color(rgba(0.0, 0.0, 0.0, 0.2));
  }

  for i in 0..N {
    let t = i as f32 / N as f32 * PI * 2.0;
    let c = ((index * 0.036 + t).sin() + (index * 0.022 - t).cos()) * 0.01;
    let d = ((index * 0.033 + t).cos() + (index * 0.020 - t).sin()) * 0.01;
    let r = t.sin() * 25.0 + 30.0;
    let p = pt2(
      (index * d * 0.05 + c + t).sin() * 0.4,
      (index * c * 0.05 + d + t).cos() * 0.35,
    ) * win.wh();
    draw.scale_axes(vec3(1.0, -1.0, 1.0))
      .ellipse()
      .xy(p)
      .w_h(r * 2.0, r * 2.0)
      .color(hsva(t.sin() * 0.15 + 0.15, 1.0, 1.0, 0.4));
  }

  draw.to_frame(app, &frame).unwrap();
}