Pac-man Game in Python

This is a simple implementation of the arcade game Pac-man written in Python. The original source code is from Free Python Games.

Introduction

In the arcade game Pac-man the player controls the yellow token. The goal is to eat all pellets (small yellow dots) within a maze to win a level. Each pellet eaten by moving Pac-man over it increases the players score by one point. To make things difficult there are also four ghosts (red token) in the maze who try to stop Pac-man. When a ghost reaches Pac-mans position the player loses the game. The ghosts are controlled by the computer. It is only possible to move within the maze, the walls cannot be crossed.

Controlling Pac-man

The Pac-man token can be controlled by pressing the arrow keys on the keyboard. It is possible to stop the token by not pressing a key. Be aware that the ghosts will still move on.

Limitations

The simple implementation of the game has some limitations in comparison to the original arcade game:

• There are no power pellets that strengthen Pac-man to eat ghosts to temporarily lock them up at their starting position in the middle of the map.
• There are no fruits.
• There are no portals to jump from one side of the screen to the other.
• Ghosts are stupid and will only change to a randomly selected direction if they run into a wall.
• There is only one level.

Setup

In order to run the game a local installation of Python is required, which bundles up Tkinter and turtle, which is required to let the application run in a window with graphical output. In addition, the package freegames is required, which can be installed using the python package manager from requirements.txt:

python3 -m pip install -r requirements.txt

Running the Game

The game can be started either from the command line with the following command:

python3 pacman.py

or by starting the file directly from your preferred IDE.

Exercises

Before changing the code, make sure to branch from main.

(1) Design a new maze

Create and design an additional maze for Pac-man and the ghosts

Hints

• Study the original maze array in Mazes.py
• What is the meaning of 0 and 1 in the array?
• Why is the array wrapped in lines of 20 values?

(2) Change the ghosts

Change the number of ghosts in the maze and their starting positions. Advanced: Give the ghosts their original names and colors.

Hints

• The ghosts are initialised in an array in the pacman.py file.
• Each ghost in the array is a Ghost object. Check out the respective Ghost class to find out more.
• Original ghost names and colors:
  • Blinky: red
  • Pinky: pink
  • Inky: teal
  • Clyde: orange

(3) Make the ghosts take better decisions

• Study the current decision-making of the ghosts. How do they decide which way to go?
• The ghosts should sense their surrounding for Pac-man. If Pac-man is within 3 tiles, they should chase him.
• Advanced: While chasing, the speed (moving distance) of the ghosts is slightly increased.
• Advanced: When losing sight, the speed (moving distance) of the ghosts is slightly decreased.

Hints

• The code for the ghost agents is within the file agents/Ghost.py
• The step method in the Ghost class is called each time the world is updated.

(4) Make Pac-man move autonomous

• Pac-man should no longer be controlled by humans.
• Implement an autonomous agent that controls Pac-man.
• Pac-man should sense his surrounding and avoid ghosts.
• The agent must collect all pellets to win the game.

Hints

• Create a new Pacman agent class
• Implement the step(self, game_state) method inside the new agent class, which decides for a direction based on the game_state parameter
• Replace the old pac-man instance with an instance of your agent class