Code snippet 26 - For multiplayer space invaders article

script.js

update() {
  if (gameOn) {
    if (this.ship.x) {
      this.ship.x = latestShipPosition;
    } else {
      this.ship = this.physics.add
        .sprite(latestShipPosition, config.height - 32, "ship")
        .setOrigin(0.5, 0.5);
      this.ship.x = latestShipPosition;
    }
    for (let item in this.visibleBullets) {
      if (this.visibleBullets[item].toLaunch) {
        this.visibleBullets[item].toLaunch = false;
        this.createBullet(this.visibleBullets[item]);
      } else {
        this.visibleBullets[item].bulletSprite.y -= 20;
        if (
          this.visibleBullets[item].bulletSprite.y < 0 ||
          this.visibleBullets[item].id == bulletThatShotSomeone
        ) {
          this.visibleBullets[item].bulletSprite.destroy();
          delete this.visibleBullets[item];
        }
      }
    }
  }

  for (let item in this.avatars) {
    if (!players[item]) {
      this.avatars[item].destroy();
      delete this.avatars[item];
    }
  }

  for (let item in players) {
    let avatarId = players[item].id;
    if (this.avatars[avatarId] && players[item].isAlive) {
      this.avatars[avatarId].x = players[item].x;
      this.avatars[avatarId].y = players[item].y;
      if (avatarId == myClientId) {
        document.getElementById("score").innerHTML =
          "Score: " + players[item].score;
      }
    } else if (!this.avatars[avatarId] && players[item].isAlive) {
      if (players[item].id != myClientId) {
        let avatarName =
          "avatar" +
          players[item].invaderAvatarType +
          players[item].invaderAvatarColor;
        this.avatars[avatarId] = this.physics.add
          .sprite(players[item].x, players[item].y, avatarName)
          .setOrigin(0.5, 0.5);
        this.avatars[avatarId].setCollideWorldBounds(true);
        document.getElementById("join-leave-updates").innerHTML =
          players[avatarId].nickname + " joined";
        setTimeout(() => {
          document.getElementById("join-leave-updates").innerHTML = "";
        }, 2000);
      } else if (players[item].id == myClientId) {
        let avatarName = "avatar" + players[item].invaderAvatarType;
        this.avatars[avatarId] = this.physics.add
          .sprite(players[item].x, players[item].y, avatarName)
          .setOrigin(0.5, 0.5);
        this.avatars[avatarId].setCollideWorldBounds(true);
        amIalive = true;
      }
    } else if (this.avatars[avatarId] && !players[item].isAlive) {
      this.explodeAndKill(avatarId);
    }
  }
  this.publishMyInput();
}