Again, we start from our game logic. Open the box2dcargame.js JavaScript file in a text editor.

We set up a destination ground in the ground creation code and assign it to our gamewinWall reference inside the carGame global object instance as follows:

carGame.gamewinWall = createGround(1200, 215, 15, 25, 0);

Next, we move on to the step function. In each step, we get the complete contact list from the world and check whether any two colliding objects are the car and the destination ground:

function checkCollision() {
  // loop all contact list 
  // to check if the car hits the winning wall.
  for (var cn = carGame.world.GetContactList(); cn != null; cn = cn.GetNext()) {
    var body1 = cn.GetFixtureA().GetBody();
    var body2 = cn.GetFixtureB().GetBody();
    if ((body1 === carGame.car && body2 === carGame.gamewinWall) || (body2 === carGame.car &&amp...