78 lines, 5 of them comments · 607 tokens, written in 6 seconds for $0.0018

 1  let particles = [];
 2  
 3  class Particle {
 4    constructor(x, y) {
 5      this.pos = createVector(x, y);
 6      this.vel = createVector(random(-3, 3), random(-8, -3));
 7      this.acc = createVector(0, 0.2);
 8      this.life = 255;
 9      this.hue = random(0, 360);
10      this.size = random(4, 12);
11    }
12  
13    update() {
14      this.vel.add(this.acc);
15      this.vel.x *= 0.98; // slight air resistance
16      this.pos.add(this.vel);
17      this.life -= 4;
18    }
19  
20    display() {
21      colorMode(HSB);
22      noStroke();
23      fill(this.hue, 80, 100, this.life / 255);
24      ellipse(this.pos.x, this.pos.y, this.size);
25      colorMode(RGB);
26    }
27  
28    isDead() {
29      return this.life <= 0;
30    }
31  }
32  
33  function setup() {
34    createCanvas(800, 600);
35    colorMode(HSB);
36    background(0);
37  }
38  
39  function draw() {
40    background(0, 0, 0, 25); // trail effect
41  
42    // Add particles continuously when mouse is pressed
43    if (mouseIsPressed) {
44      for (let i = 0; i < 5; i++) {
45        particles.push(new Particle(mouseX, mouseY));
46      }
47    }
48  
49    // Occasionally add particles at random bottom positions
50    if (random(1) < 0.1) {
51      particles.push(new Particle(random(width), height));
52    }
53  
54    for (let i = particles.length - 1; i >= 0; i--) {
55      let p = particles[i];
56      p.update();
57      p.display();
58      if (p.isDead()) {
59        particles.splice(i, 1);
60      }
61    }
62  
63    // Title text
64    fill(255, 30);
65    textAlign(CENTER);
66    textSize(14);
67    text("Click and drag to create particle bursts", width / 2, 30);
68  }
69  
70  function mousePressed() {
71    for (let i = 0; i < 30; i++) {
72      particles.push(new Particle(mouseX, mouseY));
73    }
74  }
75  
76  function windowResized() {
77    resizeCanvas(800, 600);
78  }