static  void
vesa_setpage_bio(unsigned short page, unsigned w)
{
        union REGS r;

        r.x.ax = 0x4f05;        /* 4fh/05h: Page service.       */
        r.h.bh = 0x00;          /* bh = 0: set, bl = window     */
        r.h.bl = w;        /* bh = 0: set, bl = window     */
        r.x.dx = page;          /* In granularity units.        */

        int86(0x10, & r, & r);
        if (r.x.ax != 0x004f)
        {       printf("Error in function 0x4f/0x05\n");
                return;
        }
}

static  void
vesa_setpage_dir(unsigned short page, unsigned w)
{
        _SI = _SI;              /* Force save register variables.       */
        _DI = _DI;

        _DX = page;             /* In granularity units.        */
        _BX = w;           /* bh = 0: set, bl = window     */
        (* gcx.wpos)();
}

void     (* vesa_setpage)(unsigned short, unsigned) = vesa_setpage_bio;

void draw_bitmap(BITMAP *bmp,dword alleft, dword altop,dword scrwidth)
{
  dword j;
  dword screen_offset = scrwidth -(scrwidth-alleft);
  dword bitmap_offset = 0;
  dword cor = 0;
  byte resul = 0;

  if( (scrwidth*altop) > 65535){
    resul = (scrwidth*altop)/65536;
    set_video_win(resul);
    screen_offset += (scrwidth*altop)%65536;
  }

  for(j=0;j<bmp->height;j++)
  {
   // memcpy(&VGA[screen_offset],&bmp->data[bitmap_offset],bmp->width);
    for(int icpy = 0; icpy < bmp->width; icpy++)
    {
      VGA[screen_offset] = bmp->data[bitmap_offset];
      screen_offset++;bitmap_offset++;

    } //for
       screen_offset +=  scrwidth-bmp->width;
       if(screen_offset>65535){
        cor =  screen_offset-65536;
        resul++;
        set_video_win(resul);
        screen_offset = scrwidth -(scrwidth-alleft) + cor;

       }

  } //for
}

  if( (palit = (char*) malloc(num_colors*4)) == NULL){
    fclose(fp);
    set_mode(TEXT_MODE);
    printf("Error allocating memory for palitra %s size %d . \n",file,(num_colors*4) );
    getch();
    exit(1);
  }

  fread(palit,(num_colors*4) , 1, fp);

  for(int i = 0; i < num_colors; i++, palit+=4){
   _remappalette(  i, (palit[2] << 15) | (palit[1]<<7 ) | palit[0]  );
  }

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