Hey there, aspiring game developers and Python enthusiasts! Are you ready to embark on an exciting journey into the world of game development? Well, you’re in for a treat because we’re about to find out how to create video games in Python, everyone’s favorite programming language!
Now, you might be thinking, “Hold on a second, isn’t game development super complex and reserved for coding gurus?” Fear not! I’m here to bust that myth wide open. Making games in Python is like putting together a puzzle – each piece fits snugly into place, and before you know it, you’ve crafted something incredible.
In this guide, we’re going to peel back the curtain on game development, taking you step-by-step through the process of crafting your very own video game. We’re talking about that nostalgic, bouncing-ball, paddle-pinging experience known as Pong! But guess what? We’re going to make it from scratch, using Python and a sprinkle of imagination.
So, whether you’re a coding newcomer or a Python pro looking for a new creative outlet, get ready to roll up your sleeves and let’s create some gaming magic together. By the end of this journey, you’ll have a fully functional Pong game that you can proudly show off to your friends, and you’ll discover that making games in Python is not only achievable but also incredibly fun and dare I say, actually pretty easy! Ready? Let’s hit that “Play” button and get started!
Setting Up Your Game Dev Playground
Alright, let’s get started on our journey into the world of game development using Python! If you’re new to coding or haven’t worked with Python before, don’t worry – I’ve got your back. I’ll guide you step by step to make sure you’re all set up and ready to create your very own game.
Step 1: Install Python
Python is the language we’ll be using to craft our games. If you don’t have Python installed, no worries! Just follow these simple steps:
1. Visit the official Python website: www.python.org
2. Click on the “Downloads” tab.
3. Choose the latest version of Python for your operating system (Windows, macOS, or Linux).
4. Download the installer and run it.
5. During installation, make sure to check the box that says “Add Python to PATH” (this will make things easier later).
6. Once the installation is complete, open a command prompt (Windows) or terminal (macOS/Linux) and type `python –version`, or `python3 –version` on the Mac. If it shows the version number, you’re good to go!
Step 2: Install Pygame
Pygame is a library that makes game development in Python a breeze. To install Pygame, follow these steps:
1. Open a command prompt or terminal.
2. Type the following command and press Enter:pip install pygame
(If you encounter any issues with `pip`, you might need to use `pip3` instead: `pip3 install pygame`)
Wait for the installation to complete. Once it’s done, you’ve got Pygame at your fingertips!
Step 3: Choose a Code Editor
A code editor is where you’ll write and organize your game’s code. If you’re new to coding, you can start with a simple text editor like Notepad (Windows) or TextEdit (macOS). For a more feature-rich experience, you might consider using Visual Studio Code (VSCode) – it’s free and beginner-friendly. I used VSCode for this tutorial, I found it to be the easiest editor to use. I recommend installing the Microsoft Python extension for syntax highlighting as well.
Step 4a: Test Your Setup
Let’s make sure everything’s working as expected. Open your code editor and create a new file. Type the following code:print("Hello, Game World!")
Save the file with a `.py` extension (for example, `hello.py`). Now, open a command prompt or terminal, navigate to the folder where you saved the file, and type:python hello.py
On Mac, you may need to type python3 instead. If you see “Hello, Game World!” printed on the screen, congratulations – your setup is working perfectly!
Step 4b: Test Pygame
Since pygame is an addon to python, it makes sense to test it as well, to make sure it was installed properly. To do this, type in the following code into a new file pygame_test.py:
import pygame
pygame.init()
# Set up the display
screen = pygame.display.set_mode((640, 480))
# Fill the screen with a color (white in this case)
screen.fill((255, 255, 255))
# Update the display
pygame.display.update()
# Wait for a few seconds before closing the window
pygame.time.wait(3000)
pygame.quit()This code imports pygame, initialises it, and fills the screen with white, and then closes the window after 3 seconds.
Save the script, and open a command prompt or terminal, navigate to the folder where you saved the file, and type:python hello.py
On Mac, type “python3” instead.
Its important to run this in an external terminal and not in VSCode’s terminal, otherwise it won’t work, you won’t see the pygame window pop up.
If you see a window pop up that is filled with white, that means pygame is working!
With your game development playground ready, you’ve taken the crucial first steps. In the next part of this guide, I’ll dive into creating your very own Pong game using Python and Pygame. Get ready to turn your game-making dreams into reality!
Creating Your First Game: The Classic Pong
Alright, time to roll up those sleeves and dive into creating your very first game using Python and Pygame! We’re going to start with a classic: Pong – that iconic game where two paddles bounce a ball back and forth. Don’t worry, I’ll break it down step by step, making sure you understand each piece of the puzzle.
Step 1: Setting the Game Window
First things first, let’s create a window where our game will be played. Open your code editor and create a new Python file. Then, paste in the following code:
import pygame
# Initialize Pygame
pygame.init()
# Set up the display (window) dimensions
screen_width = 800
screen_height = 600
screen = pygame.display.set_mode((screen_width, screen_height))
# Set the window title
pygame.display.set_caption("Pong Game")
# Game loop
running = True
while running:
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
pygame.quit()Here’s a breakdown of what this code does:
– We import the `pygame` module to access its functionality.
– Pygame is initialized using `pygame.init()`.
– We set up the dimensions of our game window using `screen_width` and `screen_height`.
– The game window is created using `pygame.display.set_mode()` with the specified dimensions.
– The window title is set to “Pong Game” using `pygame.display.set_caption()`.
– We start a game loop using a `while` loop. This loop will keep the game running until we decide to quit.
Step 2: Handling User Input
Now, let’s add the ability for players to control the paddles using their keyboards. Add the following code to your file:
# Paddle dimensions and properties
paddle_width = 15
paddle_height = 100
paddle_speed = 5
# Paddle positions
player_paddle = pygame.Rect(50, (screen_height - paddle_height) // 2, paddle_width, paddle_height)
opponent_paddle = pygame.Rect(screen_width - 50 - paddle_width, (screen_height - paddle_height) // 2, paddle_width, paddle_height)
# Game loop (continued)
keys = pygame.key.get_pressed()
if keys[pygame.K_w] and player_paddle.top > 0:
player_paddle.y -= paddle_speed
if keys[pygame.K_s] and player_paddle.bottom < screen_height:
player_paddle.y += paddle_speedHere’s what’s happening in this part of the code:
– We define the dimensions and speed of the paddles.
– Two `pygame.Rect` objects are created to represent the player’s paddle and the opponent’s paddle. These rectangles define the position, dimensions, and properties of the paddles.
– Within the game loop, we use `pygame.key.get_pressed()` to check for keyboard input. If the “W” key is pressed and the player’s paddle is not at the top of the screen, the paddle’s position is adjusted upwards. If the “S” key is pressed and the paddle is not at the bottom of the screen, the paddle’s position is adjusted downwards.
Step 3: Rendering the Game
Finally, let’s render the paddles and the game window. Add the following code within the game loop:
# Clear the screen
screen.fill((0, 0, 0))
# Draw paddles
pygame.draw.rect(screen, (255, 255, 255), player_paddle)
pygame.draw.rect(screen, (255, 255, 255), opponent_paddle)
# Update the display
pygame.display.flip()This code does the following:
– The screen is cleared with a black color using `screen.fill()`.
– The player’s paddle and the opponent’s paddle are drawn on the screen using `pygame.draw.rect()`.
– The display is updated using `pygame.display.flip()` to show the changes.
Step 4: Quitting the Game
To complete the game loop and allow players to exit the game, add the following code at the end of the game loop:
# Quit the game if the window is closed
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
# Quit Pygame
pygame.quit()This code ensures that the game loop continues to run as long as the window is open. If the player closes the window, the loop exits and Pygame is properly shut down.
The final code for this step should look like this:
import pygame
# Initialize Pygame
pygame.init()
# Set up the display (window) dimensions
screen_width = 800
screen_height = 600
screen = pygame.display.set_mode((screen_width, screen_height))
# Set the window title
pygame.display.set_caption("Pong Game")
# Paddle dimensions and properties
paddle_width = 15
paddle_height = 100
paddle_speed = 5
# Paddle positions
player_paddle = pygame.Rect(50, (screen_height - paddle_height) // 2, paddle_width, paddle_height)
opponent_paddle = pygame.Rect(screen_width - 50 - paddle_width, (screen_height - paddle_height) // 2, paddle_width, paddle_height)
# Game loop
running = True
while running:
keys = pygame.key.get_pressed()
if keys[pygame.K_w] and player_paddle.top > 0:
player_paddle.y -= paddle_speed
if keys[pygame.K_s] and player_paddle.bottom < screen_height:
player_paddle.y += paddle_speed
# Clear the screen
screen.fill((0, 0, 0))
# Draw paddles
pygame.draw.rect(screen, (255, 255, 255), player_paddle)
pygame.draw.rect(screen, (255, 255, 255), opponent_paddle)
# Update the display
pygame.display.flip()
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
pygame.quit()Congratulations, you’ve just created the foundation of your very own Pong game using Python and Pygame! In the next section, we’ll take things a step further by adding the ball and making it move around the screen.
Adding the Ball and Movement
Now that we have our paddles in place, it’s time to introduce the star of the show – the ball! Our goal is to make the ball bounce around the screen and create that classic Pong experience.
Step 1: Adding the Ball
Add the following code just before the game loop to create and position the ball:
# Ball properties
ball_width = 15
ball = pygame.Rect(screen_width // 2 - ball_width // 2, screen_height // 2 - ball_width // 2, ball_width, ball_width)
# Ball movement
ball_speed_x = 7
ball_speed_y = 7Here’s what this code does:
- We define the width of the ball and create a
pygame.Rectobject to represent the ball’s position and dimensions. ball_speed_xandball_speed_ydetermine the initial movement speed of the ball in the horizontal and vertical directions, respectively.
Step 2: Moving the Ball
Now, let’s update the game loop to move the ball and add collision detection to make it bounce off the walls.
Add the following code within the game loop, after updating the paddle positions:
# Move the ball
ball.x += ball_speed_x
ball.y += ball_speed_y
# Ball collision with walls
if ball.top <= 0 or ball.bottom >= screen_height:
ball_speed_y = -ball_speed_y
# Ball collision with paddles
if ball.colliderect(player_paddle) or ball.colliderect(opponent_paddle):
ball_speed_x = -ball_speed_x
And then add this code right after the paddles are drawn:
# Draw the ball
pygame.draw.ellipse(screen, (255, 255, 255), ball)This code accomplishes the following:
- We update the ball’s position based on its speed in both the horizontal and vertical directions.
- We check if the ball’s top edge hits the top of the screen or if its bottom edge hits the bottom of the screen. If either condition is met, the ball’s vertical speed is reversed, making it bounce.
- We check if the ball collides with either the player’s or opponent’s paddle. If a collision occurs, the ball’s horizontal speed is reversed, simulating the bounce.
- We draw the ball on the screen in its latest position
With these additions, your Pong game should now have a moving ball that bounces off the walls and the paddles. It’s starting to come to life!
However, you may have noticed the ball briefly appears, and then rapidly goes off of the screen to the bottom right! There’s a good reason why this is happening, so in the next section we will take a look at see what is happening and what needs to happen to fix it.
Making the Game Device Independent
The way the code has been written so far, each device that the code runs on will render it at a different speed depending on how fast the processor is. So on my Mac, the ball appears briefly and goes very fast off screen. If we ran it on a slow computer, the ball would move slower.
But we do not want this, we want a game that runs the same on any device it is played on. In game development, it’s crucial to have consistent behavior across different devices and frame rates. Pygame doesn’t have a built-in Time.deltaTime like Unity does, but we can implement a similar concept to control the speed of the ball regardless of the frame rate.
Here’s how you can achieve this by incorporating the concept of delta time into your Pygame code:
Step 1: Calculate Delta Time
Before the game loop, add the following lines to calculate delta time and initialize a clock object:
# Initialize the clock
clock = pygame.time.Clock()
# Initialize delta time
delta_time = 0Step 2: Calculate Delta Time Inside the Game Loop
Within the game loop, add the following code to calculate delta time and use it to update the ball’s position:
# Inside the game loop
running = True
while running:
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Move the ball
ball.x += ball_speed_x * delta_time
ball.y += ball_speed_y * delta_time
# Ball collision with walls
if ball.top <= 0 or ball.bottom >= screen_height:
ball_speed_y = -ball_speed_y
# Ball collision with paddles
if ball.colliderect(player_paddle) or ball.colliderect(opponent_paddle):
ball_speed_x = -ball_speed_x
# Clear the screen
screen.fill((0, 0, 0))
# Draw paddles
pygame.draw.rect(screen, (255, 255, 255), player_paddle)
pygame.draw.rect(screen, (255, 255, 255), opponent_paddle)
# Draw the ball
pygame.draw.ellipse(screen, (255, 255, 255), ball)
# Update the display
pygame.display.flip()
pygame.quit()In this updated code, we calculate delta time using clock.tick(60), where 60 represents the target frame rate (frames per second). We then use delta time to control the movement of the ball. This ensures that the ball’s speed remains consistent regardless of the frame rate of the device.
By implementing delta time, you’ll achieve more consistent and device-independent movement in your game.
When you run the game now, you might notice the ball looks like it’s sitting still in the middle of the screen now. That’s because the speed is set to 7, and with delta time implemented, the movement speed is now far too slow.
So to compensate for it, set ball_speed_x and ball_speed_y to 100 or greater. You can set ball_speed_y to 0 for now so the ball doesn’t move diagonally
Now, the ball should be moving slowly to the right, and it will hit the opponent paddle and bounce off. You can also hit the ball with your paddle, but you’ll notice that the ball will just go back and forth horizontally with no vertical movement.
This is because we aren’t actually calculating any vertical movement yet, we are just reversing the movement of the ball.
To make the ball’s speed vary upon collisions, you can introduce a random variation to the ball’s speed when it collides with a paddle. You can achieve this by adding the following code inside the section where the ball collides with paddles:
if ball.colliderect(player_paddle) or ball.colliderect(opponent_paddle):
ball_speed_x = -ball_speed_x
# Adjust ball's vertical speed based on collision point
collision_point = (ball.centery - (player_paddle.centery + opponent_paddle.centery) / 2) / (player_paddle.height / 2)
ball_speed_y = collision_point * 100 # Adjust the factor as neededIt’s no fun playing by yourself, so next, we will add an AI player to play against.
Adding an AI Player
Let’s work on implementing a basic AI opponent that can track the ball’s movement and attempt to intercept it.
Here’s how you can add simple AI player movement to your Pong game:
Step 1: AI Paddle Movement
Add the following code just before the game loop to define the AI paddle’s initial position and speed:
# AI paddle properties
ai_paddle = pygame.Rect(screen_width - paddle_width - 50, screen_height // 2 - paddle_height // 2, paddle_width, paddle_height)
ai_paddle_speed = 7 # Adjust the speed as neededStep 2: Implement AI Movement
Inside the game loop, after updating the player’s paddle position, add the following code to move the AI paddle based on the ball’s position:
# Inside the game loop
running = True
while running:
keys = pygame.key.get_pressed()
# Player paddle movement
if keys[pygame.K_w] and player_paddle.top > 0:
player_paddle.y -= paddle_speed
if keys[pygame.K_s] and player_paddle.bottom < screen_height:
player_paddle.y += paddle_speed
# AI paddle movement (follow the ball's y position)
if ai_paddle.centery < ball.centery:
ai_paddle.y += ai_paddle_speed * delta_time
if ai_paddle.centery > ball.centery:
ai_paddle.y -= ai_paddle_speed * delta_time
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Move the ball
ball.x += ball_speed_x * delta_time
ball.y += ball_speed_y * delta_time
# Ball collision and drawing code (unchanged)
…
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
# Quit Pygame
pygame.quit()This code makes the AI paddle track the ball’s y position by moving up or down to intercept the ball’s path. The AI paddle’s speed is controlled by the ai_paddle_speed value.
Feel free to adjust the AI paddle’s speed and behavior to match your desired level of challenge. You can make the AI more or less aggressive by tweaking its movement behavior.
You will need to also remove the opponent_paddle definition as well as renaming all occurrences of opponent_paddle to ai_paddle, since we don’t need the original non-ai paddle anymore.
With the AI movement implemented, your Pong game will now have an opponent to play against.
We still don’t have a full game yet, there is no way to keep track of score or know who won the game or even when the game is over.
In the next part of our journey, we’ll tackle scoring, game over conditions, and adding some final touches to make our Pong game even more engaging and fun to play. Get ready to take your game to the next level!
Implementing the Scoring system
Displaying the score on the screen involves rendering text using Pygame’s font capabilities.
Here’s a step-by-step guide on how to add a simple score display to your Pong game:
Step 1: Import the Font Module
import pygame
from pygame.locals import *
import random
import sys
# Initialize Pygame
pygame.init()
# Set up the screen
# ... (existing code)Step 2: Create a Font Object
After importing the pygame.font module, create a font object to define the appearance of the text. You can add this code just after initializing the screen:
# Create a font object
font = pygame.font.Font(None, 72) # You can adjust the font size as neededStep 3: Display the Score
Inside the game loop, after drawing the paddles and the ball, you can add code to render and display the score. You’ll need to render the scores as text using the font you created. Here’s an example of how to display the scores for both players:
# Inside the game loop
running = True
player_score = 0
ai_score = 0
while running:
# Handle events and user input
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Update the ball position and collision
# ... (existing code)
# Update the display
screen.fill((0, 0, 0))
# Draw paddles and ball
# ... (existing code)
# Display the scores
player_score_text = font.render(str(player_score), True, (255, 255, 255))
ai_score_text = font.render("AI: " + str(ai_score), True, (255, 255, 255))
screen.blit(player_score_text, (20, 20)) # Adjust the position as needed
screen.blit(ai_score_text, (screen_width - ai_score_text.get_width() - 20, 20))
# Update the display
pygame.display.flip()
# Quit Pygame
pygame.quit()Step 4: Define Score Variables
Before the game loop, define variables to keep track of the scores for both players:
# Before the game loop
player_score = 0
ai_score = 0Step 5: Update Scores When Ball Crosses Boundaries
Inside the game loop, after updating the ball’s position, check if the ball has crossed the left or right boundaries of the screen. If it has, increment the appropriate player’s score and reset the ball’s position. Here’s an example of how you can do this:
# Inside the game loop
running = True
while running:
# Handle events and user input
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Update the ball position and collision
# ... (existing code)
# Check if ball crosses boundaries
if ball.right >= screen_width:
# Player scores a point
player_score += 1
ball.x = screen_width // 2 - ball_width // 2
ball.y = screen_height // 2 - ball_width // 2
elif ball.left <= 0:
# AI scores a point
ai_score += 1
ball.x = screen_width // 2 - ball_width // 2
ball.y = screen_height // 2 - ball_width // 2
# Update the display
screen.fill((0, 0, 0))
# Draw paddles and ball
# ... (existing code)
# Display the scores
player_score_text = font.render("Player: " + str(player_score), True, (255, 255, 255))
ai_score_text = font.render("AI: " + str(ai_score), True, (255, 255, 255))
screen.blit(player_score_text, (20, 20)) # Adjust the position as needed
screen.blit(ai_score_text, (screen_width - ai_score_text.get_width() - 20, 20))
# Update the display
pygame.display.flip()
# Quit Pygame
pygame.quit()This code checks if the ball’s right boundary exceeds the screen width (indicating the player’s side) or if the ball’s left boundary is less than or equal to 0 (indicating the AI’s side). If the conditions are met, the respective player’s score is incremented, and the ball’s position is reset to the center of the screen.
With this implementation, the scores will increase when a player scores a point by hitting the ball past their opponent.
Defining a Win Condition
The scoring is now in place, but the score will count up endlessly, with no end to the game. It’s time now to implement a win condition, so that there is a winner of the game, and a game over condition.
We will say that if a player’s score reaches 5 points, the player wins, and the game ends.
Step 1: Define a Win Condition
Before the game loop, define a variable to store the winning score:
# Before the game loop
winning_score = 5Step 2: Check for a Winner
Inside the game loop, after updating the scores, check if either player has reached the winning score. If a player reaches the winning score, transition to the game over state.
# Inside the game loop
running = True
while running:
# Handle events and user input
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Update the ball position and collision
# ... (existing code)
# Check if ball crosses boundaries
if ball.right >= screen_width:
# Player scores a point
player_score += 1
ball.x = screen_width // 2 - ball_width // 2
ball.y = screen_height // 2 - ball_width // 2
elif ball.left <= 0:
# AI scores a point
ai_score += 1
ball.x = screen_width // 2 - ball_width // 2
ball.y = screen_height // 2 - ball_width // 2
# Check for a winner
if player_score >= winning_score or ai_score >= winning_score:
running = False # End the game loop
# Update the display
screen.fill((0, 0, 0))
# Draw paddles and ball
# ... (existing code)
# Display the scores
player_score_text = font.render("Player: " + str(player_score), True, (255, 255, 255))
ai_score_text = font.render("AI: " + str(ai_score), True, (255, 255, 255))
screen.blit(player_score_text, (20, 20)) # Adjust the position as needed
screen.blit(ai_score_text, (screen_width - ai_score_text.get_width() - 20, 20))
# Update the display
pygame.display.flip()
# Game over state
game_over_text = font.render("Game Over", True, (255, 255, 255))
screen.blit(game_over_text, (screen_width // 2 - game_over_text.get_width() // 2, screen_height // 2 - game_over_text.get_height() // 2))
pygame.display.flip()
# Wait for a moment before quitting
pygame.time.wait(2000) # Wait for 2 seconds
# Quit Pygame
pygame.quit()With this implementation, the game loop will exit and display a “Game Over” message on the screen when either the player or the AI reaches the winning score. The game will wait for a moment (2 seconds in this case) before quitting.
Implementing Sound Effects
Pygame provides functionality for playing sound effects, and it’s relatively straightforward to integrate sound into your game.
Here’s how you can add a sound effect when the ball hits a paddle:
Step 1: Load Sound Effect
Before the game loop, load the sound effect using the pygame.mixer.Sound class:
# Before the game loop
pygame.mixer.init() # Initialize the mixer
paddle_hit_sound = pygame.mixer.Sound('paddle_hit.wav') # Replace with your sound file pathMake sure to replace ‘paddle_hit.wav’ with the actual path to your sound effect file.
I used freesound.org to find this pong game sound, and used Audacity to just export out the one sound I liked into a new file:
https://freesound.org/people/mickdow/sounds/177409/
Step 2: Play Sound Effect on Collision
Inside the game loop, after checking for collisions between the ball and paddles, play the sound effect when a collision occurs:
# Inside the game loop
running = True
while running:
# Handle events and user input
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Update the ball position and collision
# ... (existing code)
# Check if ball collides with paddles
if ball.colliderect(player_paddle) or ball.colliderect(ai_paddle):
ball_speed_x = -ball_speed_x
paddle_hit_sound.play() # Play the sound effect
# Check if ball crosses boundaries
# ... (existing code)
# Check for a winner
# ... (existing code)
# Update the display
# ... (existing code)In the code above, paddle_hit_sound.play() is used to play the sound effect when a collision occurs between the ball and a paddle.
Step 3: Quitting the Mixer
After the game loop and before quitting Pygame, make sure to quit the mixer:
# After the game loop
pygame.mixer.quit()This should add a sound effect each time the ball hits a paddle in your Pong game. Feel free to customize the sound effect, adjust its volume, or add other sound effects as desired.
A sound could be added when a player scores, for example, in the same way.
Final Fixes
These are just a few minor tweaks and fixes that were made after the main program was completed.
Spin Angle
This simple implementation of pong does not have the concept of the player “putting English” on the ball. We can try to implement a simple version of this by doing adding some spin to the ball when it hits the paddle.
Step 1: Calculate Spin Angle
Add this to the Ball and paddle collision if statement:
# Apply spin angle based on collision point
spin_angle = collision_point * max_spin_angle # Adjust max_spin_angle as needed
ball_speed_x, ball_speed_y = rotate_vector(ball_speed_x, ball_speed_y, spin_angle)In this code, we calculate a spin_angle based on the collision point. This angle determines the amount of spin to apply to the ball. Then, we use a rotate_vector function (which you’ll need to implement) to adjust the ball’s trajectory based on the spin angle. This can simulate the effect of “english” on the ball.
Step 2: Implement the Rotate Vector Function
You’ll need to implement a function that rotates a vector (ball’s speed) by a given angle. Here’s an example of how you can implement this function at the top of the program:
import math
def rotate_vector(x, y, angle):
radians = math.radians(angle)
new_x = x * math.cos(radians) - y * math.sin(radians)
new_y = x * math.sin(radians) + y * math.cos(radians)
return new_x, new_yAdjust the max_spin_angle value and fine-tune the rotation function as needed to achieve the desired spin effect.
Keep in mind that this approach provides a basic simulation of spin and may not fully capture all the nuances of real physics. Adding more advanced spin behavior could involve more complex calculations and physics simulation.
The initial value for max_spin_angle will depend on the desired gameplay and how pronounced you want the spin effect to be. It’s a value that you can adjust and fine-tune to achieve the desired balance between realism and gameplay.
Here are a few suggestions to help you choose an initial value for max_spin_angle:
Moderate Spin (Realistic Feel): If you’re aiming for a moderate spin effect that feels somewhat realistic but doesn’t dominate the gameplay, you could start with a value between 5 and 20 degrees.
Strong Spin (Gameplay Emphasis): For a more pronounced spin effect that adds an interesting gameplay element, you could start with a value between 30 and 45 degrees.
Experimentation: You might want to start with a value around 10 to 15 degrees and then playtest your game to see how it feels. You can gradually increase or decrease the value based on player feedback and your own assessment.
Remember that the impact of max_spin_angle can also be influenced by other factors, such as the ball’s speed, paddle size, and collision mechanics. You may need to adjust multiple parameters to achieve the desired overall gameplay experience.
As you implement and test the spin effect, consider observing how different values affect the behavior of the ball when it hits the paddle and how it interacts with the overall game dynamics. This iterative process of testing and adjusting will help you find the optimal value for your game.
I ended up choosing 10 for the max spin angle as I felt it created the most action for the game. Some of the other values seemed to slow it down or have no difference, you can try them out and decide for yourself.
AI paddle positioning
You may have noticed that the AI player’s paddle goes off the screen if it goes near the top or bottom of the screen. We can fix that with this code:
After the code to calculate the AI paddle movement, add this:
if ai_paddle.top > 0:
ai_paddle.y -= paddle_speed
if ai_paddle.bottom < screen_height:
ai_paddle.y += paddle_speedThis will keep the paddle from going off the screen
Drawing a center line
To draw the dotted line (also known as the centerline) in the middle of the screen, you can add a drawing routine to your game loop that renders the line. Here’s how you can do it:
# Inside the game loop
running = True
while running:
# Handle events and user input
# Calculate delta time
delta_time = clock.tick(60) / 1000.0 # 60 frames per second
# Update the ball position and collision
# ... (existing code)
# Check if ball collides with paddles
# ... (existing code)
# Check if ball crosses boundaries
# ... (existing code)
# Check for a winner
# ... (existing code)
# Update the display
screen.fill((0, 0, 0)) # Clear the screen
# Draw paddles and ball
# ... (existing code)
# Draw the centerline
pygame.draw.line(screen, (255, 255, 255), (screen_width // 2, 0), (screen_width // 2, screen_height), 1)
# Display the scores
# ... (existing code)
# Update the display
pygame.display.flip()
# Game over state
# ... (existing code)In the code above, the pygame.draw.line() function is used to draw a vertical line in the center of the screen. The line is drawn from the top of the screen to the bottom of the screen, and its color is set to white (255, 255, 255).
Adjust the line’s thickness (currently set to 1) as needed to achieve the desired visual appearance.
Place this code after drawing the paddles and before displaying the scores. This will ensure that the centerline is drawn on top of the paddles and below the scores.
Adding the centerline can help recreate the classic Pong look and feel in your game. If you want a dotted center line, use this code instead:
# Draw the dotted centerline
dot_interval = 10 # Adjust the interval between dots
for y in range(0, screen_height, dot_interval * 2):
pygame.draw.line(screen, (255, 255, 255), (screen_width // 2, y), (screen_width // 2, y + dot_interval), 1)Conclusion
I have placed my final version of the code in Github here, I leave it as an exercise to the reader to look at it and see what other minor tweaks and differences it has to the code in this article.
In this tutorial, we’ve embarked on an exciting journey into the world of game development using Python. By creating a simple Pong game, we’ve explored fundamental concepts that serve as building blocks for more complex game projects. As you’ve seen, even with no prior game development experience, Python offers an accessible and enjoyable way to bring your gaming ideas to life.
We began by setting up the development environment, ensuring that we had the necessary tools like Python and Pygame installed. We dived into the mechanics of game loops, understanding how they drive the flow of our game and keep it responsive to player input.
From there, we delved into the core mechanics of our Pong game, creating paddles, a ball, and implementing collision detection. We learned about delta time and how it helps maintain consistent gameplay across different devices.
By adding an AI opponent, scoring system, and sound effects, we expanded our game’s features and made it more engaging. We explored how to handle user input, respond to collisions, and even introduced a touch of “english” to the ball’s movement.
Whether you’re a seasoned programmer or a curious beginner, the journey of making a video game in Python offers valuable insights into programming logic, problem-solving, and creative expression. Game development encourages you to think critically, experiment, and iterate until you achieve the desired gameplay experience.
As you move forward in your game development journey, keep in mind that this tutorial only scratches the surface of what’s possible. The world of game development is vast and ever-evolving, with endless opportunities to learn, create, and innovate.
So, take the knowledge and skills you’ve gained here and let your imagination run wild. Whether you’re creating your version of Pong, crafting intricate RPGs, or experimenting with entirely new game mechanics, remember that every line of code brings your virtual worlds to life, one pixel at a time.
Now, armed with the foundation of game development in Python, it’s time to unleash your creativity and embark on the exciting adventure of creating your own captivating games. Happy coding, and may your games be as enjoyable to create as they are to play!
You can check out the Pygame docs for more information on how to make games with Python. Also, there is a book you can purchase for a minimum $3 amount called Pygame 4000 which has examples and more tutorials on making games with Python (Disclosure: I have no affiliation with them and I do not receive any commission for linking to them).
Leave your comments down below and let me know what you think!