let helixRadius = 100;

let numSegments = 100;

let angleIncrement = 0.2;

let segmentLength = 25;

let speedIncrement = 0.01; // The amount by which the speed will be increased or decreased

let speed = 0.05; // Initial speed of rotation

​

function setup() {

  createCanvas(400, 700);

  angleMode(RADIANS);

  noFill();

  background(0);

}

​

function draw() {

  background(0, 0, 0, 80);

  translate(width / 2, 0);

​

  if (mouseIsPressed && mouseY > 0 && mouseY < height) {

    helixRadius = map(mouseX, 0, width, 50, 150);

    segmentLength = map(mouseY, 0, height, 10, 40);

  }

​

  for (let i = 0; i < numSegments; i++) {

    let angle1 = i * angleIncrement + angle;

    let angle2 = angle1 + PI; // 180 degrees phase shift

    let x1 = helixRadius * sin(angle1);

    let y1 = i * segmentLength;

    let x2 = helixRadius * sin(angle2);

    let y2 = (i + 1) * segmentLength;

​

    if (x1 < width / 2) {

      ellipse(x1, y1, 10, 10);

      ellipse(x2, y2, 10, 10);

      stroke(random(150, 175), random(150, 255), random(150, 200));

      line(x1, y1, x2, y2);

    }

  }

  // Rotate the entire helix

  angle += speed;

}

​

function keyPressed() {

  if (keyCode === UP_ARROW) {

    speed += speedIncrement; // Increase the speed

  } else if (keyCode === DOWN_ARROW) {

    speed = max(0, speed - speedIncrement); // Decrease the speed, but not less than 0

  }

}

​