Snippet: Update a body's position and rotation

updatePosition

/**
 * Updates the x and y properties of a body based on its
 * velocityX and velocityY, and, updates the rotation of
 * a body based on its rotationalVelocity.
 *
 * @param {Object} body: The body must be an Object 
 * with x, y, rotation, velocityX, velocityY, and 
 * rotationalVelocity properties.
 */
updatePosition(body) {
  body.x += body.velocityX;
  body.y += body.velocityY;
  body.rotation += body.rotationalVelocity;
},