​

/*

 * @name Rotate

 * @description Rotating a square around the Z axis.

 * To get the results you expect, send the rotate function angle

 * parameters that are values between 0 and PI*2 (TWO_PI which is

 * roughly 6.28). If you prefer to think about angles as degrees

 * (0-360), you can use the radians() method to convert your values.

 * For example: rotate(radians(90)) is identical to the statement

 * rotate(PI/2). In this example, every even numbered second a jitter

 * is added to the rotation. During odd seconds, rotation moves CW and

 * CCW at the speed determined by the last jitter value.

 */

​

let angle = 0.0;

​

function setup() {

  createCanvas(720, 400);

  noStroke();

  fill(255);

  //Draw the rectangle from the center and it will also be the

  //rotate around that center

  rectMode(CENTER);

}

​

function draw() {

  background(51);

​

  // during even-numbered seconds (0, 2, 4, 6...) add jitter to

  // the rotation

  //if (second() % 2 === 0) {

   // jitter = random(-0.1, 0.1);

  //}

  //increase the angle value using the most recent jitter value

  //angle = angle + jitter;

  //angle += 0.001;

  if (mouseX <= width/2){

      angle += 0.001;

​

  }

  //use cosine to get a smooth CW and CCW motion when not jittering

  //let c = sin(angle);

  //move the shape to the center of the canvas

  translate(width / 2, height / 2);

  //apply the final rotation

  //rotate(angle);

  rotate(angle);

  rect(0, 0, 180, 180);

​

}

​