C++ Snake game using raylib - Beginner Tutorial 🐍 (OOP)

Introduction

In this tutorial, we will create a Snake game using C++ and the raylib library, focusing on Object-Oriented Programming (OOP) principles. This guide is designed for beginners, providing a clear, step-by-step approach to building the game, adding features, and enhancing its visual appeal.

Step 1: Setting Up Your Environment

• Install C++ compiler (GCC or Clang recommended).
• Download and install raylib from the official raylib website.
• Set up your IDE (Visual Studio Code is recommended) with the raylib library.

Clone the starter template from the provided GitHub repository

• Starter Template

Step 2: Creating the Game Loop

• Implement the main game loop which will handle the game's execution flow.
• Use the following structure:

  while (!WindowShouldClose()) {
      BeginDrawing();
      ClearBackground(RAYWHITE);
      
      // Game logic and rendering calls go here
  
      EndDrawing();
  }
  

• This loop continuously processes input, updates game state, and draws the game until the window is closed.

Step 3: Creating the Food

• Define a Food class to represent the food objects in the game.
• Add attributes such as position and a method to generate a new food item at a random location.
• Example code snippet:

  class Food {
      Vector2 position;
  public
      void spawnFood() {
          position.x = GetRandomValue(0, screenWidth / cellSize) * cellSize;
          position.y = GetRandomValue(0, screenHeight / cellSize) * cellSize;
      }
  };
  

Step 4: Creating the Snake

• Define a Snake class with attributes for the snake's body segments and direction.
• Implement methods to initialize the snake and render it on the screen.
• Example code for rendering:

  void Snake::draw() {
      for (const auto& segment : body) {
          DrawRectangle(segment.x, segment.y, cellSize, cellSize, DARKGREEN);
      }
  }
  

Step 5: Moving the Snake

• Capture user input for snake movement (up, down, left, right) using the raylib input functions.
• Update the snake's position based on the current direction.
• Example code for handling input:

  if (IsKeyDown(KEY_UP)) direction = UP;
  if (IsKeyDown(KEY_DOWN)) direction = DOWN;
  

Step 6: Making the Snake Eat the Food

• Detect collision between the snake's head and the food.
• When a collision is detected, call the method to spawn new food and update the snake's length.
• Example code for collision detection:

  if (CheckCollisionRecs(snake.head, food.position)) {
      food.spawnFood();
      snake.grow();
  }
  

Step 7: Making the Snake Grow Longer

• In the Snake class, implement a method to add a new segment to the snake's body when it eats food.
• Example code for growing the snake:

  void Snake::grow() {
      body.push_back(body.back()); // Adding a new segment
  }
  

Step 8: Checking for Collisions

• Implement collision detection logic to check if the snake hits the walls or itself.
• Use raylib’s collision functions to handle this.
• Example code to check for wall collisions:

  if (snake.head.x < 0 || snake.head.x >= screenWidth || 
      snake.head.y < 0 || snake.head.y >= screenHeight) {
      // Handle game over
  }
  

Step 9: Adding Title and Frame

• Use raylib functions to draw a title and frame around the game screen.
• Example code for adding a title:

  DrawText("Snake Game", screenWidth / 2 - 50, 10, 20, BLACK);
  

Step 10: Adding Score

• Create a scoring system that increases whenever the snake eats food.
• Display the score on the screen using raylib's drawing functions.
• Example code for displaying score:

  DrawText(TextFormat("Score: %d", score), 10, 10, 20, BLACK);
  

Step 11: Adding Sounds

• Incorporate sound effects for eating food or game over using raylib's audio features.
• Load sound files and play them at appropriate times.
• Example code for playing a sound:

  PlaySound(eatSound);
  

Conclusion

By following these steps, you will have created a fully functional Snake game using C++ and raylib. This tutorial covered the game loop, food and snake creation, movement, collision detection, scoring, and sound effects. For further enhancements, consider adding levels, increasing difficulty, or creating a menu system. Happy coding!