Tic-Tac-Toe: Multiplayer

Add room system and matchmaking for private games.

1. Server: Room Management

The server already has room support (from tictactoe-server.md). Let’s add matchmaking:

# server/matchmaking.py

waiting_players = {}  # room_id → player_id
active_games = {}     # room_id → Game


async def quick_match(player_id: str) -> dict:
    """Find or create a game."""
    # Check for waiting players
    for room_id, waiting_id in list(waiting_players.items()):
        if waiting_id != player_id:
            # Found a match!
            del waiting_players[room_id]
            return {"room_id": room_id, "opponent": waiting_id}

    # No match — create new room and wait
    room_id = "room_%d" % hash(player_id) % 100000
    waiting_players[room_id] = player_id
    return {"room_id": room_id, "waiting": True}


async def cancel_match(player_id: str) -> dict:
    """Cancel waiting for a match."""
    for room_id, waiting_id in list(waiting_players.items()):
        if waiting_id == player_id:
            del waiting_players[room_id]
            return {"cancelled": True}
    return {"error": "not_waiting"}

2. Server: Add Matchmaking Endpoints

# server/main.py — add to routes

from matchmaking import quick_match, cancel_match

async def handle_quick_match(ctx: Context) -> dict:
    player_id = ctx.intent.metadata.get("player_id")
    return await quick_match(player_id)


async def handle_cancel_match(ctx: Context) -> dict:
    player_id = ctx.intent.metadata.get("player_id")
    return await cancel_match(player_id)


from evoid import Intent, Level
from evoid.core.extend import add_intent

add_intent(Intent(name="quick_match", level=Level.STANDARD), handle_quick_match)
add_intent(Intent(name="cancel_match", level=Level.STANDARD), handle_cancel_match)

3. Client: Quick Match Button

Update the lobby:

# scripts/lobby.gd — add quick match

@onready var quick_match_button: Button = $QuickMatchButton
@onready var private_button: Button = $PrivateButton


func _ready() -> void:
    quick_match_button.pressed.connect(_on_quick_match)
    private_button.pressed.connect(_on_private_game)
    EvoidBus.subscribe(EvoidTopics.GAME_EVENT, _on_game_event)


func _on_quick_match() -> void:
    status_label.text = "Searching for opponent..."
    EvoidApp.send_intent("quick_match", {"player_id": player_id})


func _on_private_game() -> void:
    var room = room_input.text.strip_edges()
    if room.is_empty():
        status_label.text = "Enter a room name"
        return
    EvoidApp.connect_to_server("ws://localhost:8000/ws", room)


func _on_game_event(payload: Dictionary) -> void:
    var event_type = payload.get("type", "")

    match event_type:
        "match_found":
            var room_id = payload.get("room_id")
            status_label.text = "Match found! Joining..."
            EvoidApp.connect_to_server("ws://localhost:8000/ws", room_id)
        "waiting":
            status_label.text = "Waiting for opponent..."

4. Client: Turn Indicator

Show whose turn it is:

# scripts/main.gd — update _on_game_event

func _on_game_event(payload: Dictionary) -> void:
    var event_type = payload.get("type", "")

    match event_type:
        "player_joined":
            _on_player_joined(payload)
        "move_made":
            _on_move_made(payload)
        "game_over":
            _on_game_over(payload)


func _on_move_made(payload: Dictionary) -> void:
    var game = payload.get("game", {})
    var current_turn = game.get("current_turn", "")

    if current_turn == player_id:
        $HUD/InfoLabel.text = "Your turn (%s)" % my_mark
    else:
        $HUD/InfoLabel.text = "Opponent's turn"

5. Client: Game History

Show move history:

# scripts/main.gd — add move history

var move_history: Array = []


func _on_move_made(payload: Dictionary) -> void:
    var player = payload.get("player_id", "")
    var position = payload.get("position", 0)
    var mark = payload.get("mark", "")

    move_history.append({
        "player": player,
        "position": position,
        "mark": mark,
    })

    _update_history_ui()


func _update_history_ui() -> void:
    var history_text = "Moves:\n"
    for move in move_history:
        var pos_name = ["TL", "TC", "TR", "ML", "MC", "MR", "BL", "BC", "BR"][move["position"]]
        history_text += "%s: %s at %s\n" % [move["mark"], move["player"], pos_name]
    $HUD/HistoryLabel.text = history_text

6. Test Multiplayer

1. Start server
2. Open two Godot instances
3. Both click “Quick Match”
4. Server matches them
5. Play!

What You Learned

Next

Now let’s deploy as WebGL — Web Deploy.