64 lines, 1 of them comments · 1,506 tokens, written in 18 seconds for $0.079

 1  let particles = [];
 2  const NUM = 1500;
 3  let t = 0;
 4  const BG = [230, 30, 8];
 5  
 6  function setup() {
 7    createCanvas(windowWidth, windowHeight);
 8    colorMode(HSB, 360, 100, 100, 100);
 9    background(BG[0], BG[1], BG[2]);
10    for (let i = 0; i < NUM; i++) {
11      particles.push(makeParticle());
12    }
13  }
14  
15  function makeParticle() {
16    return {
17      x: random(width),
18      y: random(height),
19      px: 0,
20      py: 0,
21      hue: random(180, 320),
22      speed: random(0.8, 2.2),
23      life: random(100, 500)
24    };
25  }
26  
27  function draw() {
28    // fade previous frame slightly to create trails
29    noStroke();
30    fill(BG[0], BG[1], BG[2], 4);
31    rect(0, 0, width, height);
32  
33    t += 0.0025;
34    strokeWeight(1.2);
35  
36    for (let p of particles) {
37      const angle = noise(p.x * 0.0018, p.y * 0.0018, t) * TWO_PI * 4;
38      p.px = p.x;
39      p.py = p.y;
40      p.x += cos(angle) * p.speed;
41      p.y += sin(angle) * p.speed;
42      p.life--;
43  
44      const brightness = map(p.speed, 0.8, 2.2, 70, 100);
45      stroke(p.hue, 60, brightness, 45);
46      line(p.px, p.py, p.x, p.y);
47  
48      if (p.x < 0 || p.x > width || p.y < 0 || p.y > height || p.life <= 0) {
49        Object.assign(p, makeParticle());
50      }
51    }
52  }
53  
54  function mousePressed() {
55    noiseSeed(floor(random(100000)));
56    background(BG[0], BG[1], BG[2]);
57    for (let p of particles) Object.assign(p, makeParticle());
58  }
59  
60  function windowResized() {
61    resizeCanvas(windowWidth, windowHeight);
62    background(BG[0], BG[1], BG[2]);
63  }
64