MyFirstGame.cpp

// How to Play:
// WASD to move, ESC to Quit Game
// You play as yellow Square, your goal is to kill the Red Square by touching it
// Kill red Square by touching on it
// Kill 10 times to win!


#include <iostream>
#include <cstdlib>
#include <time.h>
#include <SDL2/SDL.h>
using namespace std;


int CollisionWallX(int posX, int blockWidth, int screenWidth)
{
    // Check collision on X

    if(posX < 0)
        posX = posX + 10;
    
    if(posX + blockWidth > screenWidth)
        posX = posX - 10;

    return(posX);

}



int CollisionWallY(int posY, int blockHeight, int screenHeight)
{
    // Check collision on Y

    if(posY < 0)
        posY = posY + 10;
    
    if(posY + blockHeight > screenHeight)
        posY = posY - 10;

    return(posY);

}



bool CollisionEnemy(SDL_Renderer* render, int x, int y, int enemyX, int enemyY, int blockWidth, int blockHeight)
{

    if((x + blockWidth) >= enemyX && x <= (enemyX + blockWidth) && (y + blockHeight) >= enemyY && y <= (enemyY + blockHeight))
        return true;

    else
        return false;
        
}


void RenderRect(SDL_Renderer* render, int x, int y, int blockWidth, int blockHeight)
{

    // Rectangle coordinates and dimention
    SDL_Rect rect = {x, y, blockWidth, blockHeight};

        
    SDL_SetRenderDrawColor(render, 255, 255, 0, 255);
	SDL_RenderFillRect(render, &rect);

}



void EnemyRenderRect(SDL_Renderer* render, int x, int y, int blockWidth, int blockHeight)
{

    // Rectangle coordinates and dimention
    SDL_Rect rect = {x, y, blockWidth, blockHeight};

    // Enemy will render red 
    SDL_SetRenderDrawColor(render, 255, 0, 0, 255);
	SDL_RenderFillRect(render, &rect);

}










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


	SDL_Window* window;

	SDL_Init(SDL_INIT_VIDEO);

    // Window dimentions
	int width = 640;
	int height = 480;

	window = SDL_CreateWindow("My First Game!", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, SDL_WINDOW_RESIZABLE | SDL_WINDOW_OPENGL);

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


	bool running = true;
	SDL_Event ev;
    
    // Initial coordinates of block(0, 0)
    int playerX, playerY, enemyX, enemyY;
    playerX = 80;
    playerY = 80;

    // Uses time to randomly generate  seed
    srand(time(0));
    // Enemy appears on different coordinates every time
    enemyX = rand() % (width - 50);
    enemyY = rand() % (height - 50);

    // Rectangle dimenstions
    int blockWidth, blockHeight;
    blockWidth = 50;
    blockHeight = 50;

    // Declare Variable
    bool enemyCollision;

    // kill 10 times to win game
    int kill;


    // Loop of window running
    while(running)
	{
        // Check for collision
        enemyCollision = CollisionEnemy(render, playerX, playerY, enemyX, enemyY, blockWidth, blockHeight);
		
        // Events, where everything happens
		while(SDL_PollEvent(&ev) != 0)
		{
			if(ev.type == SDL_QUIT)
				running = false;
            


            else if(ev.type == SDL_KEYDOWN)
            {
                switch( ev.key.keysym.sym )
                {
                    // Moving Player

                    case SDLK_w:
                    playerY = playerY - 5;
                    break;

                    case SDLK_s:
                    playerY = playerY + 5;
                    break;

                    case SDLK_a:
                    playerX = playerX - 5;
                    break;

                    case SDLK_d:
                    playerX = playerX + 5;
                    break;

                    case SDLK_ESCAPE:
                    running = false;
                    break;
                    
                }
            }



		}

        if(enemyCollision != false)
        {
            // Uses time to randomly generate  seed
            srand(time(0));
            // Enemy appears on different coordinates every time
            enemyX = rand() % (width - 50);
            enemyY = rand() % (height - 50);
            
            enemyCollision = 0;

            // Kill count;
            kill = kill + 1;
            
        }

        if(kill == 10)
            running = false;


        // Update window
        SDL_SetRenderDrawColor(render, 211, 211, 211, 255); // Background color
        SDL_RenderClear(render);


        // Check Collision
        playerX = CollisionWallX(playerX, blockWidth, width);
        playerY = CollisionWallY(playerY, blockHeight, height);



        // Render Rectangle
        RenderRect(render, playerX, playerY, blockWidth, blockHeight);

        // Render Enemy Rectangle
        EnemyRenderRect(render, enemyX, enemyY, blockWidth, blockHeight);


    

        // Render what's left
        SDL_RenderPresent(render);
		SDL_UpdateWindowSurface(window);
    }



    // End/Destroy everything
	SDL_DestroyWindow(window);
	SDL_Quit();


    return 0;

}