typedef struct BITMAP          /* a bitmap structure */
{                              
   int w, h;                   /* width and height in pixels */
   int clip;                   /* flag if clipping is turned on */
   int cl, cr, ct, cb;         /* clip left, right, top and bottom values */
   GFX_VTABLE *vtable;         /* drawing functions */
   void (*write_bank)(void);   /* write bank selector, see bank.s */
   void (*read_bank)(void);    /* read bank selector, see bank.s */
   void *dat;                  /* the memory we allocated for the bitmap */
   int bitmap_id;              /* for identifying sub-bitmaps */
   void *extra;                /* points to a structure with more info */
   int x_ofs;         	    /* horizontal offset (for sub-bitmaps) */
   int y_ofs;                  /* vertical offset (for sub-bitmaps) */
   int seg;                    /* bitmap segment */
   unsigned char *line[0];     /* pointers to the start of each line */
} BITMAP;

typedef struct RGB
{
   unsigned char r, g, b;
   unsigned char filler;
} RGB;

#define PAL_SIZE     256

typedef RGB PALLETE[PAL_SIZE];

#include "allegro.h" // hlav. soubor. allegra

int main(void)
{
  int result, i;
  BITMAP *bmp;
  PALETTE pal;
  RGB pal_swap;
  char* soubor = "c:\\windows\\mraky.bmp";

  if ( (result = allegro_init() ) != 0 )  // inicializuje allegro
  {
    printf("Nejde Allegro! - %s\n\nZmackni cokoliv.",allegro_error);
    getch();
    return 0;
  }
  // nahodi mod 640 * 480 * 8

  set_color_depth(8);
  if ( (result = set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) ) < 0) {
    set_gfx_mode(GFX_TEXT, 80, 25, 0, 0);
    printf("Nejde grafika! - %s\n\nZmackni cokoliv.",allegro_error);
    getch();
    allegro_exit();
    return 0;
  }


  // nacte bitmapu ze souboru
  bmp = load_bitmap(soubor, pal);

  set_palette(pal);
  // tzv. plivne to na obrazovku
  blit(bmp, screen, 0, 0, 0, 0, bmp->w, bmp->h);

  while (!kbhit())
  {

    pal_swap = pal[0];
    for (i = 0; i < 255; i++)
    {
     pal[i] = pal[i + 1];

    }

    pal[255] = pal_swap;

  }

  // ziska paletu a ulozi obsah na obr.
  get_palette(pal);
  bmp = create_sub_bitmap(screen, 0, 0, SCREEN_W, SCREEN_H);
  save_bitmap("mraky.pcx", bmp, pal);

  // uvolni pamet
  destroy_bitmap(bmp);

  allegro_exit();

  return 0;
}