​

function setup() {

  createCanvas(windowWidth, windowHeight);

  background(255, 0, 0);

}

​

​

function draw() {

  fill(value);

  rect(25, 25, 50, 50);

}

​

function touchMoved(px) {

  console.log( )

  /*

  value = value + 5;

  if (value > 255) {

    value = 0;

  }

  */

  if (px < width/2) {

    value = 0;

  } else if (px > width/2) {

    value = 255;

  }

}