SDL_PixelFormat -- Stores surface format information

typedef struct SDL_PixelFormat {
  SDL_Palette *palette;
  Uint8  BitsPerPixel;
  Uint8  BytesPerPixel;
  Uint8  Rloss, Gloss, Bloss, Aloss;
  Uint8  Rshift, Gshift, Bshift, Ashift;
  Uint32 Rmask, Gmask, Bmask, Amask;
  Uint32 colorkey;
  Uint8  alpha;
} SDL_PixelFormat;