SDL tutorial 6

//http://www.youtube.com/user/thecplusplusguy
//Thanks for the typed in code to Tapit85
//you may need an image call tree_key.bmp with the background 00ffff (which disappear)
#include <SDL/SDL.h>

int main(int argc, char** argv)
{
    SDL_Init(SDL_INIT_EVERYTHING);
    SDL_Surface *screen, *image;    // every surface except for screen needs to be freed
    screen = SDL_SetVideoMode(640, 480, 32, SDL_SWSURFACE);
//  screen = SDL_SetVideoMode(640, 480, 32, SDL_SWSURFACE|SDL_FULLSCREEN);
    bool running = true;
    const int FPS = 30;
    Uint32 start;
    bool b[4] = {0,0,0,0};
    SDL_Rect rect;
    rect.x = 10;
    rect.y = 10;
    rect.w = 20;
    rect.h = 20;
    Uint32 color = SDL_MapRGB(screen->format, 0xff,0xff,0xff);
    Uint32 color2 = SDL_MapRGB(screen->format, 0,0,0);
    image = SDL_DisplayFormat(SDL_LoadBMP("tree_key.bmp")); // better to check later if image is NULL
    SDL_SetColorKey(image, SDL_SRCCOLORKEY, SDL_MapRGB(screen->format, 0x00, 0xff, 0xff));
    while(running) {
        start = SDL_GetTicks();
        SDL_Event event;
        while(SDL_PollEvent(&event)) {
            switch(event.type) {
                case SDL_QUIT:
                    running = false;
                    break;
                case SDL_KEYDOWN:
                    switch(event.key.keysym.sym) {
                        case SDLK_UP:
                            b[0] = 1;
                            break;
                        case SDLK_LEFT:
                            b[1] = 1;
                            break;
                        case SDLK_DOWN:
                            b[2] = 1;
                            break;
                        case SDLK_RIGHT:
                            b[3] = 1;
                            break;

                    }
                    break;
                case SDL_KEYUP:
                    switch(event.key.keysym.sym) {
                        case SDLK_UP:
                            b[0] = 0;
                            break;
                        case SDLK_LEFT:
                            b[1] = 0;
                            break;
                        case SDLK_DOWN:
                            b[2] = 0;
                            break;
                        case SDLK_RIGHT:
                            b[3] = 0;
                            break;

                    }
                    break;
            }
        }

        //logic
        if(b[0])
            rect.y--;
        if(b[1])
            rect.x--;
        if(b[2])
            rect.y++;
        if(b[3])
            rect.x++;

        //render
        SDL_FillRect(screen, &screen->clip_rect, color);    // fill the screen white (maybe better outside while loop)
//      SDL_FillRect(screen, &rect, color2);
//      SDL_Rect rect;
        rect.x = 200;
        rect.y = 100;
        SDL_BlitSurface(image, NULL, screen, NULL); // copy image to screen to specified coordinates
        SDL_BlitSurface(image, NULL, screen, &rect);
        SDL_Flip(screen);

        if(1000/FPS > SDL_GetTicks()-start) {
            SDL_Delay(1000/FPS-(SDL_GetTicks()-start));
        }
    }
    SDL_FreeSurface(image);
    SDL_Quit();
    return 0;
}