SDL tutorial 17

#include <SDL/SDL.h>

//void putpixel(SDL_Surface* screen, int x, int y)
//{
//  Uint8* pixels = (Uint8*)screen->pixels;
//  Uint8* pixel = pixels + y*screen->pitch + x; // offset of pointer
//  *pixel = SDL_MapRGB(screen->format,0xff,0xff,0xff);
//}

// 32 Bit (not yet working correctly)
void putpixel(SDL_Surface* screen, int x, int y)
{
    Uint32* pixels = (Uint32*)screen->pixels;
    Uint32* pixel = pixels + y*screen->pitch/4 + x; // offset of pointer
    *pixel = SDL_MapRGB(screen->format,0xff,0xff,0xff);
}

int main(int argc, char** argv)
{
    SDL_Init(SDL_INIT_EVERYTHING);
    SDL_Surface *screen;
//  screen = SDL_SetVideoMode(640, 480, 8, SDL_SWSURFACE);
    screen = SDL_SetVideoMode(640, 480, 32, SDL_SWSURFACE);
    bool running = true;
    const int FPS = 30;
    Uint32 start;
    for(int i = 0; i < 100; i += 1) {
        putpixel(screen,i,10);
    }
    putpixel(screen,20,40);
    while(running) {
        start = SDL_GetTicks();
        SDL_Event event;
        while(SDL_PollEvent(&event)) {
            switch(event.type) {
                case SDL_QUIT:
                    running = false;
                    break;
            }
        }

        //logic

        //render
        SDL_Flip(screen);
        if(1000/FPS > SDL_GetTicks()-start) {
            SDL_Delay(1000/FPS-(SDL_GetTicks()-start));
        }
    }
    SDL_Quit();
    return 0;
}