const num = 2000;

const noiseScale = 0.01;

const particles = [];

​

function setup() {

  createCanvas(600, 600);

  for (let i = 0; i < num; i++) {

    particles.push(createVector(random(width), random(height)));

    stroke(255);

  }

  background(0)

}

​

function draw() {

  background(0, 10);

​

  for (let i = 0; i < num; i++) {

    let p = particles[i];

    let n = noise(p.x * noiseScale, p.y * noiseScale);

    let a = TAU * n;

    let displacement = 5;

​

    stroke(255, 0, 0);

    point(p.x + displacement, p.y);

    stroke(0, 255, 0);

    point(p.x, p.y);

    stroke(0, 0, 255);

    point(p.x - displacement, p.y);

​

    // Invert the direction

    if (mouseX > width / 2) {

      p.x += cos(a);

      p.y += sin(a);

    } else {

      p.x -= cos(a);

      p.y -= sin(a);

    }

      // p.x -= mouseX * 0.001

      // p.y -= mouseY * 0.001

    if (!onScreen(p)) {

      p.x = random(width);

      p.y = random(height);

    }

  }

}

​

function mousePressed() {

  noiseSeed(millis());

}

​

function onScreen(v) {

  return v.x >= 0 && v.x <= width && v.y >= 0 && v.y <= height;

}