py2048base 0.48

Python clone of the famous 2048 game.

py2048 is a clone of the famous game by Gabriele Cirulli. It’s probably not very interesting to people looking for playing 2048, but may be useful for people looking for learning Python. It’s written in pure Python 3.8 and makes an effort not to use third-party libraries. For example, the game grid could be a numpy matrix, but I’d rather not break a butterfly upon a wheel. The game’s been divided in two parts: the backend, and the frontends (or interfaces).

The package in this repository provides no concrete user interface for the game, but contains a class that must be inherited by every actual frontend.

Features

• Customizable rules

  You can configure the size of the game grid and the winning condition (wanna go beyond 2048?);

• Customizable looks

  By subclassing the basic frontend and overriding its methods, you can make the game look any way you want, without touching the basic game logic;

• Automatic mode

  You can replace human input with a function that picks a random direction! More useful for testing than actual gameplay, though.

How to use

To implement a frontend

The backend takes input (in the form of a py2048.Directions object), processes it, and waits for the next input. This loops until the player exits, or the player wins for the first time in this session, or the player runs out of valid movements. It’s a pure-Python implementation of the original game logic: it makes equal numbers merge into their sum, “moving” from one tile into another, and so on. The backend deals only with plain Python data, such as int and dict; it is up to each frontend to actually collect the input and display the updated game state as a (hopefully) pretty interface.

To write such frontend, subclass py2048.basefrontend.Base2048Frontend and override the following methods:

• choose_direction

• on_player_quit

• on_player_victory

• on_player_overvictory

• on_player_loss

choose_direction must return exactly one py2048.Directions object. If writing a graphical frontend (a GUI), you’ll probably want to create a “worker” thread that runs the backend’s loop and waits for a condition when it reaches the choose_direction call. The main thread will then be responsible for storing user input somewhere accessible by the worker thread and “waking it up”. The other overriden methods shouldn’t return anything. player_quit is called when the player exits the game before winning or losing. An “overvictory” is what happens when the grid “jams” (runs out of valid movements) but the player had already won (had already reached the target goal number).

To run tests

We’re using the pytest library to check the correctness of the basic data structures. To run the tests, open a terminal, move into the root folder of the project (the one which contains setup.py), and type the following:

pytest-3 -v py2048/test.py

Make sure you’re in the right folder, that there are no slashes in the command, and that it doesn’t end with .py. Alternatively, use

make test

Wishlist

In the future, I’d like to create an AI to play the game!

---

How it works

Backend

Its main components are the Cell and the Grid. The Cell class is a wrapper over an int that represents a tile in the game grid. It has a locked property, which is simply a bool that determines whether it can change its stored int in this cycle. A cycle is what happens between the arrival of a valid user input and the moment the game pauses to get the next input. This locked property prevents a 2 merging into a 2 and the resulting 4 merging into another 4 all in a single cycle, for example. If you play the original game, you’ll notice that is not allowed.

The Grid is a wrapper over a dict that maps points into Cells (and points are named tuples that store x and y coordinates). This class (along with py2048.basefrontend.Base2048Frontend), implements most of the game logic. It’s responsible for determining how and when one Cell can merge into another, updating the score, and so on.

Frontend