Pong Game C ITP380

Pong is one of the first-ever video games, developed in 1972. Its minimalist design and engaging gameplay mechanics make it a classic project for budding programmers. The game involves two paddles, a ball, and a scoring system. The primary goal is to hit the ball past your opponent’s paddle while defending your side.

For students in ITP380, creating Pong offers a chance to build an interactive application while applying theoretical knowledge. It emphasizes event-driven programming, collision detection, and managing game state in real-time.

Setting Up the Development Environment

Before diving into coding, it’s essential to prepare a suitable development environment. Working with graphical libraries like SDL2 (Simple DirectMedia Layer) is often recommended for rendering visuals and handling user input. Here’s what you’ll need:

A C Compiler: GCC or the Visual Studio IDE.

SDL2 Library: This simplifies creating windows, rendering graphics, and capturing user input.

Code Editor: Visual Studio Code or an IDE of your choice for efficient coding.

Once the setup is complete, include the SDL2 library in your project and configure it to create a window for the game.

Structuring the Game in C

Developing a Pong game requires careful structuring. The primary components include paddles, the ball, collision detection, a game loop, and rendering.

Initializing SDL

Start by initializing SDL to create a window and renderer:

#include <SDL2/SDL.h>

int main(int argc, char *argv[]) {

    SDL_Init(SDL_INIT_VIDEO);

    SDL_Window *window = SDL_CreateWindow("Pong Game", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 800, 600, SDL_WINDOW_SHOWN);

    SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);

    // Game loop placeholder

    SDL_DestroyRenderer(renderer);

    SDL_DestroyWindow(window);

    SDL_Quit();

    return 0;

}

This code initializes SDL, creates a window, and sets up the renderer, which will handle graphics rendering.

Defining Game Elements

Use structures to define the paddles and the ball:

typedef struct {

    int x, y, w, h;

} Paddle;

typedef struct {

    int x, y, vx, vy;

} Ball;

These structures hold the position, dimensions, and velocity of the game elements.

Implementing the Game Loopa

The game loop is central to any interactive application. It processes events, updates the game state, and renders the visuals repeatedly:

bool running = true;

SDL_Event event;

while (running) {

    while (SDL_PollEvent(&event)) {

        if (event.type == SDL_QUIT) {

            running = false;

        }

    }

    // Update game logic

    // Render the game

}

Game Mechanics

Paddle Movement

Capture keyboard inputs to control the paddles. For instance, the arrow keys control the right paddle, while the “W” and “S” keys move the left paddle up and down:

const Uint8 *keystate = SDL_GetKeyboardState(NULL);

if (keystate[SDL_SCANCODE_W]) left_paddle.y -= 5;

if (keystate[SDL_SCANCODE_S]) left_paddle.y += 5;

if (keystate[SDL_SCANCODE_UP]) right_paddle.y -= 5;

if (keystate[SDL_SCANCODE_DOWN]) right_paddle.y += 5;

Ball Movement and Collision

The ball moves across the screen based on its velocity. Detect collisions with the paddles and screen edges to adjust its trajectory:x

ball.x += ball.vx;

ball.y += ball.vy;

// Collision with paddles

if ((ball.x <= left_paddle.x + left_paddle.w && ball.y >= left_paddle.y && ball.y <= left_paddle.y + left_paddle.h) ||

    (ball.x >= right_paddle.x - ball.vx && ball.y >= right_paddle.y && ball.y <= right_paddle.y + right_paddle.h)) {

    ball.vx = -ball.vx;

}

// Collision with screen edges

if (ball.y <= 0 || ball.y >= 600) {

    ball.vy = -ball.vy;

}

Scoring System

Implement a scoring mechanism by detecting when the ball goes past a paddle:

if (ball.x <= 0) {

    right_score++;

    resetBall(); // Function to reset ball position

}

if (ball.x >= 800) {

    left_score++;

    resetBall();

}

Rendering the Game

Drawing the paddles, ball, and score on the screen is known as rendering.  SDL’s rendering functions make this straightforward:

SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);

SDL_RenderClear(renderer);

SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);

SDL_Rect leftPaddle = {left_paddle.x, left_paddle.y, left_paddle.w, left_paddle.h};

SDL_Rect rightPaddle = {right_paddle.x, right_paddle.y, right_paddle.w, right_paddle.h};

SDL_Rect ballRect = {ball.x, ball.y, 10, 10};

SDL_RenderFillRect(renderer, &leftPaddle);

SDL_RenderFillRect(renderer, &rightPaddle);

SDL_RenderFillRect(renderer, &ballRect);

SDL_RenderPresent(renderer);

Enhancing the Game

Once the basic game is functional, enhance it by adding:

Sound Effects: Use SDL_mixer to add sound effects for ball collisions and scoring.

Difficulty Levels: Adjust paddle speed and ball velocity based on player performance.

AI Opponent: Implement a computer-controlled paddle for single-player mode.

Benefits of Developing Pong in C

This project offers multiple learning benefits for ITP380 students:

Problem-Solving: Understanding game loops and logic flow.

Graphics Programming: Using SDL2 to render objects and handle events.

Debugging Skills: Identifying and fixing logical or graphical bugs.

Real-Time Systems: Managing frame rates and input processing.

Conclusion

Creating a Pong game in C for an ITP380 course is a rewarding exercise that combines theory with practical coding. It teaches essential programming concepts while providing a tangible and interactive result. By completing this project, you gain the confidence and skills needed to tackle more complex game development challenges in the future.