snakeng

snakeng is an implementation of the back-end of the classic “snake” game. It provides an interface to inject directional inputs (up/down/right/left), and produces a data structure representing the game state, for each frame of gameplay. This allows snake to be quickly implemented and played on various platforms.

Features:

• Configurable game area width/height

• Configurable wall behaviour (teleport/wrap or death)

• Serializable game state object (if you want to e.g. save/load game states to .json files)

• Configurable snake speed options (fixed speed, or automatically increase speed as snake grows)

• Configurable apple behaviour (set time before apples disappear, or make apples permanent until collected)

For more information, see the API documentation.

Install

Install via pip:

pip install snakeng

Minimal snake game implementation

This is the simplest possible implementation of snake, using snakeng:

import sys
import time
import keyboard
from snakeng.snake import SnakeGame, Direction

dirmap = {'up': Direction.UP, 'down': Direction.DOWN, 'left': Direction.LEFT, 'right': Direction.RIGHT}

game = SnakeGame()                 # Create game instance

def keypress_event(e):
    new_direction = dirmap.get(e.name, None)
    if new_direction is not None:
        game.direction_input(new_direction)

keyboard.on_press(keypress_event)  # Register callback function to save last keypress

while True:
    new_state = game.process()                             # Produce new frame
    sys.stdout.write("\033[2J\n" + new_state.to_string())  # Clear terminal screen and print new game state
    sys.stdout.flush()                                     # Flush output
    time.sleep(0.05)

Sample command-line (ASCII) implementation

Additionally, a sample terminal-based implementation of a snake game is provided, which can be accessed by running snakeng as a module:

python -m snakeng

The terminal-based implementation accepts several arguments, detailed here:

usage: snakeng [-h] [-x WIDTH] [-y HEIGHT] [-f FPS]
               [-s {slow,medium,fast,faster}] [-w] [-o OUTPUT_FILE]
               [-i INPUT_FILE] [-p] [-a APPLE_TICKS]

Simple terminal-based snake game showing how to use snakeng. Use arrow keys to
change snake direction, use 'p' to pause, and use 'Ctrl-C' to quit.

options:
  -h, --help            show this help message and exit
  -x WIDTH, --width WIDTH
                        Game area width in characters. (default: 40)
  -y HEIGHT, --height HEIGHT
                        Game area height in characters. (default: 30)
  -f FPS, --fps FPS     Framerate in frames per second. (default: 24)
  -s {slow,medium,fast,faster}, --fixed-speed {slow,medium,fast,faster}
                        Sets the snake speed for the whole game. If unset, the
                        snake speed will automatically increase as the snake
                        size increases. (default: None)
  -w, --wall-death      If True, snake will die if it hits a wall. Default
                        behaviour is to "wrap around" and come out of the
                        opposite wall. (default: False)
  -o OUTPUT_FILE, --output-file OUTPUT_FILE
                        If set, the game state will be saved to the specified
                        filename when you quit with Ctrl-C. (default: None)
  -i INPUT_FILE, --input-file INPUT_FILE
                        If set, the game state will be loaded from the
                        specified filename. (default: None)
  -p, --permanent-apples
                        If True, apples will stay forever until collected.
                        Default is to disappear after a fixed number of
                        frames. (default: False)
  -a APPLE_TICKS, --apple-ticks APPLE_TICKS
                        Specifies the number of frames before an uncollected
                        apple disappears. Can only be used if -p is not set.
                        Default is to use the width or height of the game
                        area, whichever is larger. (default: None)
NOTE: the sample implementation uses an ANSI escape sequence to clear the terminal screen,
so it won't work in terminals that don't support ANSI escape sequences.

Contributions

Contributions are welcome, please open a pull request at https://github.com/eriknyquist/snakeng.

If you have any questions about / need help with contributions, please contact Erik at eknyquist@gmail.com.