var position;

​

function setup() {

  createCanvas(400, 400);

  start = createVector(width/2, height/2);

  end = createVector(0, 0);

  // position = createVector(start.x, start.y);

  position = start;

}

​

function draw() {

  background(220);

  var w = end.x - start.x;

  var h = end.y - start.y;

  // position.x = position.x + w / 100;

  position.x += w / 100;

  position.y += h / 100;

​

  ellipse(position.x,position.y,10,10);

}