Space shooter game - Norbo11 - SDL

#include "SDL/SDL.h"
#include "SDL/SDL_image.h"
#include "SDL/SDL_ttf.h"
#include "SDL/SDL_mixer.h"
#include <string>
#include <sstream>
#include <fstream>

using namespace std;

//constants
const int screenWidth = 1280;
const int screenHeight = 720;
const int screenBPP = 32;

const int playerSpeed = 3;
const int enemySpeed = 3;
const int laserSpeed = 6;

SDL_Event event;

//surfaces
SDL_Surface *spaceship = NULL;
SDL_Surface *enemyBig = NULL;
SDL_Surface *enemySmall = NULL;
SDL_Surface *laserBlue = NULL;
SDL_Surface *laserRed = NULL;
SDL_Surface *menuBG = NULL;
SDL_Surface *gameBG = NULL;

SDL_Surface *screen = NULL;

//music
Mix_Music *gameMusic = NULL;
Mix_Music *menuMusic = NULL;
Mix_Music *deathMusic = NULL;
Mix_Chunk *laser1 = NULL;
Mix_Chunk *laser2 = NULL;

//fonts
TTF_Font *font = NULL;
SDL_Color textColor = { 255, 255, 255 };

//variables
bool quit;
int state = 1; // 0 = MENU, 1 = GAME, 2= DEATH
std::ofstream logger( "log.txt" );

//====================================================================
//CLASSES
//====================================================================

class Laser
{
    private:
    int x;
    int y;
    int xVel;
    int yVel;
    int width;
    int height;
    int countX;
    int countY;

    public:
    bool visible;
    Laser();
    void handleLogic(int playerX, int playerY, int playerWidth);
    void render();
};

class Player
{
    private:
    int xVel;
    int yVel;
    int height;

    public:
    int x;
    int y;
    int width;
    Player();
    void handleInput(Laser laser);
    void handleLogic();
    void render();
};

//====================================================================
//FUNCTIONS
//====================================================================

void log( std::string message )
{
    //Write message to file
    logger << message << std::endl;
    //Flush the buffer
    logger.flush();
}

SDL_Surface *loadImage(std::string filename)
{
    SDL_Surface* loadedImage = NULL;
    SDL_Surface* optimizedImage = NULL;

    loadedImage = IMG_Load(filename.c_str());
    if(loadedImage != NULL)
    {
        optimizedImage = SDL_DisplayFormatAlpha(loadedImage);
        SDL_FreeSurface(loadedImage);
    }
    log("Loaded image "+filename);
    return optimizedImage;
}

void applySurface(int x, int y, SDL_Surface* source, SDL_Surface* destination)
{
    SDL_Rect offset;
    offset.x = x;
    offset.y = y;
    SDL_BlitSurface(source, NULL, destination, &offset);
}

bool loadResources()
{
    log("Loading Resources...");
    spaceship = loadImage("art/spaceship.png");
    enemyBig = loadImage("art/enemy_big.png");
    enemySmall = loadImage("art/enemy_small.png");
    laserRed = loadImage("art/laserRed.png");
    laserBlue = loadImage("art/laserBlue.png");
    menuBG = loadImage("art/menu_bg.png");
    gameBG = loadImage("art/space_bg.png");

    font = TTF_OpenFont("art/Fh_Space.ttf",25);
    if (font == NULL)
    {
        return false;
    }

    gameMusic = Mix_LoadMUS("sound/music_game.mp3");
    menuMusic = Mix_LoadMUS("sound/music_menu.ogg");
    deathMusic = Mix_LoadMUS("sound/music_death.mp3");
    laser1 = Mix_LoadWAV("sound/laser1.wav");
    laser2 = Mix_LoadWAV("sound/laser1.wav");
    log("Loaded Resources.");
    return true;
}

bool startUp()
{
    log("Initializing everything...");
     if (SDL_Init(SDL_INIT_EVERYTHING) == -1)
     {
        return false;
     }
     if (TTF_Init() == -1)
     {
        return false;
     }
     if (IMG_Init(IMG_INIT_JPG|IMG_INIT_PNG|IMG_INIT_TIF) == -1)
     {
         return false;
     }
    screen = SDL_SetVideoMode(screenWidth,screenHeight,screenBPP,SDL_SWSURFACE);
    if (screen == NULL)
    {
        return false;
    }
    if (Mix_OpenAudio(22050,MIX_DEFAULT_FORMAT,2,4096 ) == -1)
    {
        return false;
    }
    SDL_WM_SetCaption("Space Norbos",NULL);
    if (loadResources() == false)
    {
        return false;
    }
    quit = false;
    log("Done initializing.");
    return true;
}

void cleanUp()
{
    log("Cleaning up...");
    SDL_FreeSurface(gameBG);
    SDL_FreeSurface(menuBG);
    SDL_FreeSurface(spaceship);
    SDL_FreeSurface(enemyBig);
    SDL_FreeSurface(enemySmall);
    SDL_FreeSurface(laserBlue);
    SDL_FreeSurface(laserRed);
    TTF_CloseFont(font);
    Mix_FreeMusic(gameMusic);
    Mix_FreeMusic(menuMusic);
    Mix_FreeMusic(deathMusic);
    Mix_FreeChunk(laser1);
    Mix_FreeChunk(laser2);
    TTF_Quit();
    IMG_Quit();
    Mix_Quit();
    SDL_Quit();
    log("Cleaned up.");
}

void shoot(Laser laser)
{
    log("Shooting!");
    laser.visible = true;
}

//====================================================================
//CLASS FUNCTIONS
//====================================================================

//PLAYER======================================

Player::Player()
{
    x = (screenWidth/2)-(width/2);
    y = 656;
    xVel = 0;
    yVel = 0;
    width = 56;
    height = 54;
}

void Player::handleInput(Laser laser)
{
    if (event.type == SDL_KEYDOWN)
    {
        switch (event.key.keysym.sym)
        {
            case SDLK_LEFT: xVel -= playerSpeed; break;
            case SDLK_RIGHT: xVel += playerSpeed; break;
            case SDLK_SPACE: laser.visible = true;
        }
    }
    else if( event.type == SDL_KEYUP )
    {
        //Adjust the velocity
        switch( event.key.keysym.sym )
        {
            case SDLK_LEFT: xVel += playerSpeed; break;
            case SDLK_RIGHT: xVel -= playerSpeed; break;
        }
    }
}

void Player::handleLogic()
{
    x = x + xVel;
    if (x <= 0)
    {
        x = 0;
    }
    if (x + width > screenWidth)
    {
        x = screenWidth - width;
    }
    y = y + yVel;
    if (y <= 0)
    {
        y = 0;
    }
    if (y + height > screenHeight)
    {
        y = screenHeight - height;
    }
}

void Player::render()
{
    applySurface(x,y,spaceship,screen);
}

//LASER======================================

Laser::Laser()
{
    x = 0;
    y = 0;
    xVel = 0;
    yVel = (laserSpeed);
    width = 10;
    height = 50;
    countX = 0;
    countY = 0;
    visible = false;
}

void Laser::handleLogic(int playerX, int playerY, int playerWidth)
{
    if (visible == true)
    {
        if (countY == 0)
        {
            y = playerY - height - 2;
            countY += 1;
        }
        if (countX == 0)
        {
            x = playerX + (playerWidth/2)- (width/2);
            countX += 1;
        }
        y -= laserSpeed;
        if (y = 0)
        {
            visible = false;
        }
    }
}

void Laser::render()
{
    if (visible == true)
    {
        applySurface(x,y,laserBlue,screen);
    }
}

//====================================================================
//MAIN
//====================================================================

int main(int argc, char* args[])
{
    if (startUp() == false)
    {
        return 1;
    }
    Player player;
    Laser laser;
    while (quit == false)
    {
        SDL_FillRect( screen, &screen->clip_rect, SDL_MapRGB( screen->format, 0xFF, 0xFF, 0xFF ) );
        if (state == 1)
        {
            applySurface(0,0,gameBG,screen);
            while (SDL_PollEvent(&event))
            {
                player.handleInput(laser);
                switch (event.type)
                {
                    case SDL_QUIT: quit = true; break;
                }
            }
            player.handleLogic();
            player.render();
            laser.handleLogic(player.x,player.x,player.width);
            laser.render();
            if (SDL_Flip(screen) == -1)
            {
                return 1;
            }
        }
    }
    cleanUp();
    return 0;
}