Basic Unity Course

Network Lobby Screen: Join Room

Hello! In this course, we will learn how to implement a lobby screen in a network game using Unity. Specifically, we will focus on the “Join Room” feature and explain various methods. During this process, we will use Unity’s UNet to implement network functionality and later expand to other network libraries like Mirror.

1. Understanding the Concept of Network Lobby

The network lobby refers to a space where players wait before joining a specific room in multiplayer games. In the lobby, players gather to adjust game settings and perform tasks such as joining or creating rooms.

1.1 Key Features of the Lobby

• Create Room
• View Room List
• Join Room
• Leave Room
• Start and End Game

1.2 Setting Up the Network

To enable network functionality in Unity, you must first set up “Unity Multiplayer“. Install the UNet package via Unity’s Package Manager. You can develop network functionality using this package.

2. Setting Up the Project

First, create a new Unity project. Next, I will add the necessary UI components to implement the lobby screen.

using UnityEngine;
using UnityEngine.UI;

public class Lobby : MonoBehaviour
{
    public Button createRoomButton;
    public Button joinRoomButton;

    void Start()
    {
        createRoomButton.onClick.AddListener(CreateRoom);
        joinRoomButton.onClick.AddListener(JoinRoom);
    }

    void CreateRoom()
    {
        // Implement room creation logic
    }

    void JoinRoom()
    {
        // Implement room joining logic
    }
}

3. Creating a Room

To create a room, you need to set up the network manager and write the logic for creating a room. Here is an example of room creation code.

using UnityEngine.Networking;

void CreateRoom()
{
    if (NetworkServer.active)
    {
        // Cannot create a room if the server is already running.
        Debug.Log("The server is already running.");
        return;
    }

    // Set room properties
    RoomOptions roomOptions = new RoomOptions();
    roomOptions.MaxPlayers = 4; // Maximum number of players

    // Create room
    NetworkManager.singleton.CreateRoom("New Room", roomOptions);
    Debug.Log("The room has been created.");
}

4. Getting the Room List

After creating a room, we need to display the current list of existing rooms. We will learn about the necessary UI elements and how to update room information.

using UnityEngine.Networking;
using UnityEngine.UI;

public void UpdateRoomList()
{
    // Get room list
    foreach (RoomInfo room in NetworkManager.singleton.RoomList)
    {
        // Update room information in UI
        Debug.Log("Room Name: " + room.Name);
    }
}

5. Joining a Room

I will also explain how players can join a room. Here, we will add logic to receive the room name and join that room.

void JoinRoom(string roomName)
{
    if (string.IsNullOrEmpty(roomName))
    {
        Debug.Log("Room name is empty.");
        return;
    }

    NetworkManager.singleton.JoinRoom(roomName);
    Debug.Log("Joining room: " + roomName);
}

6. Leaving a Room

We can also implement the functionality to leave a room. The player will be able to leave the room and return to the lobby screen.

void LeaveRoom()
{
    if (!NetworkServer.active)
    {
        // Leave the room if not a server
        NetworkManager.singleton.LeaveRoom();
        Debug.Log("Left the room.");
        // Add logic to return to the lobby screen
    }
}

7. Starting the Game

We also need to consider the feature to start the game after all players have joined the room. We can check if all players are ready and start the game.

void StartGame()
{
    if (AllPlayersReady())
    {
        // Game start logic
        Debug.Log("Starting the game.");
    }
}

bool AllPlayersReady()
{
    // Logic to check if all players are ready
    // Testing with a simple return of true
    return true;
}

8. Testing and Debugging

Once the code is complete, we need to test it locally. Using Unity’s play mode, we should create and join rooms, finding and fixing any errors that occur during the process.

9. Implementing Additional Features

In addition to basic room creation and joining, various features can be added to enhance the lobby interface. For example, displaying room information, player status, and implementing a chat system.

10. Conclusion

Through this course, we have learned how to implement a network lobby screen in Unity and how to join rooms. Based on this foundational knowledge, you can create more complex network games. In the next course, we will learn how to further develop these features.