let sx, sy, tsx, tsy, ex, ey, x, y;

let xspeed, yspeed;

let go;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  tsx = width / 2;

  tsy = 0;

  sx = tsx;

  sy = tsy;

  ex = sx;

  ey = 10;

  init();

  stroke(255);

}

​

function draw() {

  background(0);

  if (go) {

    x += xspeed;

    y += yspeed;

  }

  line(sx, sy, x, y);

}

​

function init() {

  sx = tsx;

  sy = tsy;

  x = sx;

  y = sy;

  xspeed = (ex - tsx) / 10;

  yspeed = (ey - tsy) / 10;

  go = true;

}

​

function mousePressed() {

  go = false;

  c++;

  if (c % 2 == 0) {

    ex = mouseX;

    ey = mouseY;

    init();

  } else {

    tsx = mouseX;

    tsy = mouseY;

  }

​

}

​