let x,y;

let w,h;

​

let tlx, tly;

let trx, trry;

let brx, bry;

let blx, bly;

​

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  rectMode(CENTER);

  x= width/2;

  y= height/2;

  w= width/2;

  h= height/2

}

​

function draw() {

  background(220);

  tlx= x- w/2;

  tly= y- h/2;

  trx= x+ w/2;

  trry= y-h/2;

  brx= x+ w/2;

  bry= y+ h/2;

  blx= x- w/2;

  bly= y+ h/2;

  x= x+(mouseX-x)*0.1;

  y= y+(mouseY-y)*0.1;

​

  // TL to TR

  //line(width/2 - width/20, height/2 - height/20, width/2 + width/20, height/2 - height/20);

  line(tlx, tly, trx, trry);

​

  // TR to BR

  //line(width/2 - width/20, height/2 - height/20, width/2 + width/20, height/2 + height/20);

  line(trx, trry, brx, bry);

​

  // BR to BL

  //line(width/2 + width/20, height/2 + height/20, width/2 - width/20, height/2 + height/20);

  line(brx, bry, blx, bly);

​

  // BL to TL

  //line(width/2 - width/20, height/2 + height/20, width/2 - width/20, height/2 - height/20);

  line(blx, bly, tlx, tly);

​

}