Code snippet 21 - For multiplayer space invaders article

server.js

function calcRandomVelocity() {
  let randomShipXVelocity = Math.floor(Math.random() * 200) + 20;
  randomShipXVelocity *= Math.floor(Math.random() * 2) == 1 ? 1 : -1;
  return randomShipXVelocity;
}