​

function setup() {

  createCanvas(600, 400);

}

​

function draw() {

  background(255);

  setLineDash([5, 5]); //create the dashed line pattern here

  line(400,0,400,height)

  if(lightOn){

    fill("red")

    rect(400,0,200,400)

  } 

​

  //if the mouse came from <400 to >400

  if(mouseX>=400 && pmouseX<400){

  // lightOn mode will chande oppositely

    lightOn = !lightOn

  }

  console.log(mouseX)

  //text

  fill(0)

  textSize(15)

  textAlign(CENTER)

  text('move mouse to the rightside!->',400/2,height/2)

}

​

function setLineDash(list) {

  drawingContext.setLineDash(list);

}