Table of Contents
- Introduction
- Prerequisites
- Setting up the Project
- Creating the Game Server
- Setting up the WebSockets
- Handling Player Connections
- Implementing Real-Time Gameplay
- Conclusion
Introduction
In this tutorial, we will build a web-based real-time multiplayer game using Python and WebSockets. By the end of this tutorial, you will have a basic understanding of how to create a multiplayer game, handle player connections, and implement real-time gameplay.
Prerequisites
To complete this tutorial, you should have a basic understanding of Python programming and web development concepts. Familiarity with networking and JavaScript will also be beneficial. You will need the following:
- Python installed on your machine
- An internet browser to test the game
Setting up the Project
- Begin by creating a new directory for your project and navigate to it in your command line/terminal.
- Create a new virtual environment by running the following command:
python -m venv myenv - Activate the virtual environment:
On macOS/Linux:
source myenv/bin/activate
On Windows:
myenv\Scripts\activate
- Install the required packages:
pip install websockets - Create a new Python file called
game_server.pyin your project directory.
Creating the Game Server
In this section, we will create the main game server that will handle player connections and gameplay logic. ```python import websockets
async def handle_connection(websocket, path):
# Handle new player connection
# ...
# Implement game logic
# ...
start_server = websockets.serve(handle_connection, "localhost", 8765)
asyncio.get_event_loop().run_until_complete(start_server)
asyncio.get_event_loop().run_forever()
``` Here, we've defined the `handle_connection` function, which will handle new player connections and implement the game logic. We then create a WebSocket server using the `websockets` library and pass our connection handler to it. Finally, we run the server indefinitely.
Setting up the WebSockets
To handle player connections, we will use the WebSocket protocol. In this section, we’ll modify the handle_connection function to accept WebSocket connections.
```python
import websockets
async def handle_connection(websocket, path):
# Handle new player connection
player_id = register_player(websocket)
# Implement game logic
while True:
try:
message = await websocket.recv()
# Process player input
# ...
# Send game state updates to players
# ...
except websockets.ConnectionClosed:
# Handle player disconnection
unregister_player(player_id)
break
async def start_game():
start_server = websockets.serve(handle_connection, "localhost", 8765)
await start_server
asyncio.get_event_loop().run_until_complete(start_game())
asyncio.get_event_loop().run_forever()
``` Here, we've modified the `handle_connection` function to use the WebSocket connection `websocket.recv()` method to receive player input. You can process the input and send game state updates back to the players using the `websocket.send()` method.
Handling Player Connections
In this section, we’ll implement the logic to handle new player connections and disconnections. ```python import websockets
players = {}
def register_player(websocket):
player_id = generate_player_id()
players[player_id] = websocket
return player_id
def unregister_player(player_id):
del players[player_id]
async def handle_connection(websocket, path):
player_id = register_player(websocket)
# Implement game logic
while True:
try:
message = await websocket.recv()
# Process player input
# ...
# Send game state updates to players
# ...
except websockets.ConnectionClosed:
unregister_player(player_id)
break
``` Here, we've added a `players` dictionary to keep track of connected players. The `register_player` function generates a unique player ID, associates it with the WebSocket connection, and adds it to the `players` dictionary. The `unregister_player` function removes a player from the dictionary when they disconnect.
Implementing Real-Time Gameplay
Now that we have the basic server structure in place, we can implement the game logic. In this section, we’ll handle player input and send game state updates to all connected players. ```python import websockets
players = {}
def register_player(websocket):
player_id = generate_player_id()
players[player_id] = websocket
return player_id
def unregister_player(player_id):
del players[player_id]
async def handle_connection(websocket, path):
player_id = register_player(websocket)
# Implement game logic
while True:
try:
message = await websocket.recv()
# Process player input
if message == "left":
move_player_left(player_id)
elif message == "right":
move_player_right(player_id)
# Send game state updates to players
game_state = get_game_state()
for player in players.values():
await player.send(game_state)
except websockets.ConnectionClosed:
unregister_player(player_id)
break
``` In this example, we've added `move_player_left`, `move_player_right`, and `get_game_state` functions to handle player input and retrieve the current game state. We send the updated game state to all connected players using the `await player.send()` method.
Conclusion
Congratulations! You have successfully built a web-based real-time multiplayer game using Python and WebSockets. In this tutorial, we covered the basics of creating a game server, handling player connections, and implementing real-time gameplay. You can now expand on this foundation and add more features to your game. Happy coding!