game.player.js

// respond to key events
Game.Player.prototype.keyUp = function (e) {
  delete this._keysPressed[e.key];
};

// respond to key events
Game.Player.prototype.keyDown = function (e) {
  this._keysPressed[e.key] = true;

  this.dir = {
    up: this._keysPressed.w || this._keysPressed.ArrowUp,
    left: this._keysPressed.a || this._keysPressed.ArrowLeft,
    down: this._keysPressed.s || this._keysPressed.ArrowDown,
    right: this._keysPressed.d || this._keysPressed.ArrowRight,
  };

  if (this.dir.up || this.dir.left || this.dir.down || this.dir.right) {
    e.preventDefault();
    e.stopPropagation();
  }

  if (

    // refresh page, minimize or print
    (e.metaKey === true && (e.key === 'r' || e.key === 'm' || e.key === 'p')) ||

    // any browser key commands
    (e.altKey === true && e.metaKey === true)
    ) {
    // pass
    return;
  }

  // console.log('Player.keyDown', this.dirCount, e.key, this._keysPressed, e);
};