let carWidth, carHeight;

let carColor;

let wheelWidth, wheelHeight;

let speed;

​

function setup() {

  createCanvas(600, 600);

  //setup the car

  rectMode(CENTER);

  posX = width / 2;

  posY = height / 2;

  carWidth = 100;

  carHeight = carWidth / 2.5;

  carColor = color(255, 0, 0);

  wheelWidth = carWidth * 0.2;

  wheelHeight = wheelWidth / 2.5;

}

​

function draw() {

  background(255);

  drawCar();

  updateCar();

}

​

function drawCar() {

  //car body

  fill(carColor);

  noStroke();

  rect(posX, posY, carWidth, carHeight);

​

  fill(0);

  //left top wheel

  rect(

    posX - carWidth / 2 + wheelWidth / 2,

    posY - carHeight / 2 - wheelHeight / 2,

    wheelWidth,

    wheelHeight

  );

  //right top wheel

  rect(

    posX + carWidth / 2 - wheelWidth / 2,

    posY - carHeight / 2 - wheelHeight / 2,

    wheelWidth,

    wheelHeight

  );

  //left bottom wheel

  rect(

    posX - carWidth / 2 + wheelWidth / 2,

    posY + carHeight / 2 + wheelHeight / 2,

    wheelWidth,

    wheelHeight

  );

  //right bottom wheel

  rect(

    posX + carWidth / 2 - wheelWidth / 2,

    posY + carHeight / 2 + wheelHeight / 2,

    wheelWidth,

    wheelHeight

  );

}

​

function updateCar() {

  //drive the car

  posX += 10;

​

  if (posX > width + carWidth / 2) {

    posX = -carWidth / 2;

  }

}

​