src/msw/pnghand.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        pnghand.cpp
   3 // Purpose:     Implements a PNG reader class + handler
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "pngread.h"
  14 #pragma implementation "pnghand.h"
  15 #endif
  16
  17 // For compilers that support precompilation, includes "wx.h".
  18 #include "wx/wxprec.h"
  19
  20 #ifdef __BORLANDC__
  21 #pragma hdrstop
  22 #endif
  23
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27
  28 #if wxUSE_IOSTREAMH
  29 #   include <fstream.h>
  30 #else
  31 #   include <fstream>
  32 #endif
  33
  34 #include <windows.h>
  35 #include <wx/palette.h>
  36 #include <wx/bitmap.h>
  37 #include <wx/msw/pngread.h>
  38 #include <wx/msw/dibutils.h>
  39
  40 extern "C" {
  41 #include "png.h"
  42 }
  43
  44 extern "C" void png_read_init PNGARG((png_structp png_ptr));
  45 extern "C" void png_write_init PNGARG((png_structp png_ptr));
  46
  47 #ifndef GlobalAllocPtr
  48 #define     GlobalPtrHandle(lp)         \
  49                 ((HGLOBAL)GlobalHandle(lp))
  50
  51 #define     GlobalLockPtr(lp)                \
  52                 ((BOOL)GlobalLock(GlobalPtrHandle(lp)))
  53 #define     GlobalUnlockPtr(lp)      \
  54                 GlobalUnlock(GlobalPtrHandle(lp))
  55
  56 #define     GlobalAllocPtr(flags, cb)        \
  57                 (GlobalLock(GlobalAlloc((flags), (cb))))
  58 #define     GlobalReAllocPtr(lp, cbNew, flags)       \
  59                 (GlobalUnlockPtr(lp), GlobalLock(GlobalReAlloc(GlobalPtrHandle(lp) , (cbNew), (flags))))
  60 #define     GlobalFreePtr(lp)                \
  61                 (GlobalUnlockPtr(lp), (BOOL)GlobalFree(GlobalPtrHandle(lp)))
  62 #endif
  63
  64
  65 void
  66 ima_png_error(png_struct *png_ptr, char *message)
  67 {
  68 //        wxMessageBox(message, "PNG error");
  69
  70   longjmp(png_ptr->jmpbuf, 1);
  71 }
  72
  73
  74 // static wxGifReaderIter* iter;
  75 wxPalette *wxCopyPalette(const wxPalette *cmap);
  76
  77 wxPNGReader::wxPNGReader(void)
  78 {
  79   filetype = 0;
  80   RawImage = NULL;      //  Image data
  81
  82   Width = 0; Height = 0;       //  Dimensions
  83   Depth = 0;           // (bits x pixel)
  84   ColorType = 0;        // Bit 1 = Palette used
  85                   // Bit 2 = Color used
  86                   // Bit 3 = Alpha used
  87
  88   EfeWidth = 0;         // Efective Width
  89
  90   lpbi = NULL;
  91   bgindex = -1;
  92   Palette = 0;
  93   imageOK = FALSE;
  94 }
  95
  96 wxPNGReader::wxPNGReader ( char* ImageFileName )
  97 {
  98   imageOK = FALSE;
  99   filetype = 0;
 100   RawImage = NULL;      //  Image data
 101
 102   Width = 0; Height = 0;       //  Dimensions
 103   Depth = 0;           // (bits x pixel)
 104   ColorType = 0;        // Bit 1 = Palette used
 105                   // Bit 2 = Color used
 106                   // Bit 3 = Alpha used
 107
 108   EfeWidth = 0;         // Efective Width
 109
 110   lpbi = NULL;
 111   bgindex = -1;
 112   Palette = 0;
 113
 114   imageOK = ReadFile (ImageFileName);
 115 }
 116
 117 void
 118 wxPNGReader::Create(int width, int height, int depth, int colortype)
 119 {
 120   Width = width; Height = height; Depth = depth;
 121   ColorType = (colortype>=0) ? colortype: ((Depth>8) ? COLORTYPE_COLOR: 0);
 122
 123   if (lpbi)  {
 124 #ifdef __WIN16__
 125    GlobalFreePtr((unsigned int) lpbi);
 126 #else
 127    GlobalFreePtr(lpbi);
 128 #endif
 129 //   delete Palette;
 130   }
 131   RawImage = 0;
 132   Palette = 0;
 133   if (lpbi = DibCreate(Depth, Width, Height))  {
 134     RawImage = (ImagePointerType)DibPtr(lpbi);
 135     EfeWidth = (long)(((long)Width*Depth + 31) / 32) * 4;
 136         imageOK = TRUE;
 137   }
 138 }
 139
 140 wxPNGReader::~wxPNGReader ( )
 141 {
 142   if (lpbi)  {
 143 #ifdef __WIN16__
 144    GlobalFreePtr((unsigned int) lpbi);
 145 #else
 146    GlobalFreePtr(lpbi);
 147 #endif
 148    delete Palette;
 149   }
 150 }
 151
 152
 153 int wxPNGReader::GetIndex(int x, int y)
 154 {
 155   if (!Inside(x, y) || (Depth>8)) return -1;
 156
 157   ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 158   int index = (int)(*ImagePointer);
 159   return index;
 160 }
 161
 162 bool wxPNGReader::GetRGB(int x, int y, byte* r, byte* g, byte* b)
 163 {
 164   if (!Inside(x, y)) return FALSE;
 165
 166   if (Palette) {
 167    return Palette->GetRGB(GetIndex(x, y), r, g, b);
 168 /*   PALETTEENTRY entry;
 169    ::GetPaletteEntries((HPALETTE) Palette->GetHPALETTE(), GetIndex(x, y), 1, &entry);
 170    *r = entry.peRed;
 171    *g = entry.peGreen;
 172    *b = entry.peBlue;  */
 173   } else {
 174    ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 175    *b = ImagePointer[0];
 176    *g = ImagePointer[1];
 177    *r = ImagePointer[2];
 178   }
 179   return TRUE;
 180 }
 181
 182
 183 bool wxPNGReader::SetIndex(int x, int y, int index)
 184 {
 185   if (!Inside(x, y) || (Depth>8)) return FALSE;
 186
 187   ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 188   *ImagePointer = index;
 189
 190   return TRUE;
 191 }
 192
 193 bool wxPNGReader::SetRGB(int x, int y, byte r, byte g, byte b)
 194 {
 195   if (!Inside(x, y)) return FALSE;
 196
 197   if (ColorType & COLORTYPE_PALETTE)
 198   {
 199    if (!Palette) return FALSE;
 200    SetIndex(x, y, Palette->GetPixel(r, g, b));
 201
 202   } else {
 203    ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 204    ImagePointer[0] = b;
 205    ImagePointer[1] = g;
 206    ImagePointer[2] = r;
 207   }
 208
 209   return TRUE;
 210 }
 211
 212 bool wxPNGReader::SetPalette(wxPalette* colourmap)
 213 {
 214   if (!colourmap)
 215    return FALSE;
 216   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 217   Palette = colourmap;
 218   return (DibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 219 }
 220
 221 bool
 222 wxPNGReader::SetPalette(int n, byte *r, byte *g, byte *b)
 223 {
 224   Palette = new wxPalette();
 225   if (!Palette)
 226    return FALSE;
 227
 228   if (!g) g = r;
 229   if (!b) b = g;
 230   Palette->Create(n, r, g, b);
 231   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 232   return (DibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 233 }
 234
 235 bool
 236 wxPNGReader::SetPalette(int n, rgb_color_struct *rgb_struct)
 237 {
 238   Palette = new wxPalette();
 239   if (!Palette)
 240    return FALSE;
 241
 242   byte r[256], g[256], b[256];
 243
 244   for(int i=0; i<n; i++)
 245   {
 246    r[i] = rgb_struct[i].red;
 247    g[i] = rgb_struct[i].green;
 248    b[i] = rgb_struct[i].blue;
 249   }
 250   // Added by JACS copying from Andrew Davison's additions
 251   // to GIF-reading code
 252   // Make transparency colour black...
 253   if (bgindex != -1)
 254     r[bgindex] = g[bgindex] = b[bgindex] = 0;
 255
 256   Palette->Create(n, r, g, b);
 257   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 258   return (DibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 259 }
 260
 261 void wxPNGReader::NullData()
 262 {
 263   lpbi = NULL;
 264   Palette = NULL;
 265 }
 266
 267 wxBitmap* wxPNGReader::GetBitmap(void)
 268 {
 269     wxBitmap *bitmap = new wxBitmap;
 270     if ( InstantiateBitmap(bitmap) )
 271         return bitmap;
 272     else
 273     {
 274         delete bitmap;
 275         return NULL;
 276     }
 277 }
 278
 279 bool wxPNGReader::InstantiateBitmap(wxBitmap *bitmap)
 280 {
 281   HDC dc = ::CreateCompatibleDC(NULL);
 282
 283   if (dc)
 284   {
 285         // tmpBitmap is a dummy, to satisfy ::CreateCompatibleDC (it
 286         // is a memory dc that must have a bitmap selected into it)
 287         HDC dc2 = GetDC(NULL);
 288         HBITMAP tmpBitmap = ::CreateCompatibleBitmap(dc2, GetWidth(), GetHeight());
 289         ReleaseDC(NULL, dc2);
 290         HBITMAP oldBitmap = (HBITMAP) ::SelectObject(dc, tmpBitmap);
 291
 292         if ( Palette )
 293         {
 294             HPALETTE oldPal = ::SelectPalette(dc, (HPALETTE) Palette->GetHPALETTE(), FALSE);
 295         ::RealizePalette(dc);
 296         }
 297
 298     HBITMAP hBitmap = ::CreateDIBitmap(dc, lpbi,
 299         CBM_INIT, RawImage, (LPBITMAPINFO) lpbi, DIB_PAL_COLORS);
 300
 301         ::SelectPalette(dc, NULL, TRUE);
 302         ::SelectObject(dc, oldBitmap);
 303         ::DeleteObject(tmpBitmap);
 304         ::DeleteDC(dc);
 305
 306         if ( hBitmap )
 307         {
 308           bitmap->SetHBITMAP((WXHBITMAP) hBitmap);
 309           bitmap->SetWidth(GetWidth());
 310           bitmap->SetHeight(GetHeight());
 311           bitmap->SetDepth(GetDepth());
 312           if ( GetDepth() > 1 && Palette )
 313             bitmap->SetPalette(*Palette);
 314           bitmap->SetOk(TRUE);
 315
 316
 317           // Make a mask if appropriate
 318           if ( bgindex > -1 )
 319           {
 320             wxMask *mask = CreateMask();
 321             bitmap->SetMask(mask);
 322           }
 323       return TRUE;
 324         }
 325         else
 326         {
 327           return FALSE;
 328         }
 329   }
 330   else
 331     {
 332     return FALSE;
 333     }
 334 }
 335
 336 wxPalette *wxCopyPalette(const wxPalette *cmap)
 337 {
 338   // To get number of entries...
 339   WORD count = 0;
 340   ::GetObject((HPALETTE) cmap->GetHPALETTE(), sizeof(WORD), &count);
 341
 342   LOGPALETTE* logPal = (LOGPALETTE*)
 343      new BYTE[sizeof(LOGPALETTE) + count*sizeof(PALETTEENTRY)];
 344   logPal->palVersion = 0x300;
 345   logPal->palNumEntries = count;
 346   ::GetPaletteEntries((HPALETTE) cmap->GetHPALETTE(), 0, count, logPal->palPalEntry);
 347
 348   HPALETTE hPalette = ::CreatePalette(logPal);
 349   delete[] logPal;
 350
 351   wxPalette *newCmap = new wxPalette;
 352   newCmap->SetHPALETTE((WXHPALETTE) hPalette);
 353   return newCmap;
 354 }
 355
 356 wxMask *wxPNGReader::CreateMask(void)
 357 {
 358     HBITMAP hBitmap = ::CreateBitmap(GetWidth(), GetHeight(), 1, 1, NULL);
 359
 360   HDC dc = ::CreateCompatibleDC(NULL);
 361     HBITMAP oldBitmap = (HBITMAP) ::SelectObject(dc, hBitmap);
 362
 363     int bgIndex = GetBGIndex();
 364
 365     int x,y;
 366
 367     for (x=0; x<GetWidth(); x++)
 368     {
 369         for (y=0; y<GetHeight(); y++)
 370         {
 371             int index = GetIndex(x, y);
 372             if ( index == bgIndex )
 373                 ::SetPixel(dc, x, GetHeight() - y - 1, RGB(0, 0, 0));
 374             else
 375                 ::SetPixel(dc, x, GetHeight() - y - 1, RGB(255, 255, 255));
 376
 377       }
 378     }
 379     ::SelectObject(dc, oldBitmap);
 380     wxMask *mask = new wxMask;
 381     mask->SetMaskBitmap((WXHBITMAP) hBitmap);
 382     return mask;
 383 }
 384
 385 bool wxPNGReader::ReadFile(char * ImageFileName)
 386 {
 387   int number_passes;
 388
 389   if (ImageFileName)
 390    strcpy(filename, ImageFileName);
 391
 392   FILE *fp;
 393   png_struct *png_ptr;
 394    png_info *info_ptr;
 395   wxPNGReaderIter iter(this);
 396
 397   /* open the file */
 398   fp = fopen(filename, "rb");
 399   if (!fp)
 400     return FALSE;
 401
 402   /* allocate the necessary structures */
 403   png_ptr = new (png_struct);
 404   if (!png_ptr)
 405   {
 406     fclose(fp);
 407     return FALSE;
 408   }
 409
 410   info_ptr = new (png_info);
 411   if (!info_ptr)
 412   {
 413     fclose(fp);
 414     delete(png_ptr);
 415     return FALSE;
 416   }
 417   /* set error handling */
 418   if (setjmp(png_ptr->jmpbuf))
 419   {
 420     png_read_destroy(png_ptr, info_ptr, (png_info *)0);
 421     fclose(fp);
 422     delete(png_ptr);
 423     delete(info_ptr);
 424
 425     /* If we get here, we had a problem reading the file */
 426     return FALSE;
 427   }
 428         //png_set_error(ima_png_error, NULL);
 429
 430   /* initialize the structures, info first for error handling */
 431   png_info_init(info_ptr);
 432   png_read_init(png_ptr);
 433
 434   /* set up the input control */
 435   png_init_io(png_ptr, fp);
 436
 437   /* read the file information */
 438   png_read_info(png_ptr, info_ptr);
 439
 440   /* allocate the memory to hold the image using the fields
 441     of png_info. */
 442   png_color_16 my_background={ 0, 31, 127, 255, 0 };
 443
 444   if (info_ptr->valid & PNG_INFO_bKGD)
 445     {
 446     png_set_background(png_ptr, &(info_ptr->background),
 447       PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
 448         if ( info_ptr->num_palette > 0 )
 449             bgindex = info_ptr->background.index;
 450     }
 451   else   {
 452     png_set_background(png_ptr, &my_background,
 453       PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
 454
 455         // Added by JACS: guesswork!
 456         if ( info_ptr->num_trans != 0 )
 457             bgindex = info_ptr->num_trans - 1 ;
 458    }
 459
 460   /* tell libpng to strip 16 bit depth files down to 8 bits */
 461   if (info_ptr->bit_depth == 16)
 462     png_set_strip_16(png_ptr);
 463
 464   int pixel_depth=(info_ptr->pixel_depth<24) ? info_ptr->pixel_depth: 24;
 465   Create(info_ptr->width, info_ptr->height, pixel_depth,
 466     info_ptr->color_type);
 467
 468   if (info_ptr->num_palette>0)
 469     {
 470       SetPalette((int)info_ptr->num_palette, (rgb_color_struct*)info_ptr->palette);
 471     }
 472
 473   int row_stride = info_ptr->width * ((pixel_depth+7)>>3);
 474  //  printf("P = %d D = %d RS= %d ", info_ptr->num_palette, info_ptr->pixel_depth,row_stride);
 475 //  printf("CT = %d TRS = %d BD= %d ", info_ptr->color_type, info_ptr->valid & PNG_INFO_tRNS,info_ptr->bit_depth);
 476
 477   byte *row_pointers = new byte[row_stride];
 478
 479   /* turn on interlace handling */
 480   if (info_ptr->interlace_type)
 481     number_passes = png_set_interlace_handling(png_ptr);
 482   else
 483     number_passes = 1;
 484 //  printf("NP = %d ", number_passes);
 485
 486   for (int pass=0; pass< number_passes; pass++) {
 487   iter.upset();
 488   int y=0;
 489   do  {
 490 //    (unsigned char *)iter.GetRow();
 491     if (info_ptr->interlace_type)  {
 492      if (pass>0)
 493       iter.GetRow(row_pointers, row_stride);
 494      png_read_row(png_ptr, row_pointers, NULL);
 495     }
 496     else
 497      png_read_row(png_ptr, row_pointers, NULL);
 498
 499     iter.SetRow(row_pointers, row_stride);
 500     y++;
 501   } while(iter.PrevRow());
 502 //  printf("Y=%d ",y);
 503   }
 504   delete[] row_pointers;
 505
 506   /* read the rest of the file, getting any additional chunks
 507     in info_ptr */
 508   png_read_end(png_ptr, info_ptr);
 509
 510   /* clean up after the read, and free any memory allocated */
 511   png_read_destroy(png_ptr, info_ptr, (png_info *)0);
 512
 513   /* free the structures */
 514   delete(png_ptr);
 515   delete(info_ptr);
 516
 517   /* close the file */
 518   fclose(fp);
 519
 520   /* that's it */
 521   return TRUE;
 522 }
 523
 524
 525 /* write a png file */
 526
 527 bool wxPNGReader::SaveFile(char * ImageFileName)
 528 {
 529   if (ImageFileName)
 530    strcpy(filename, ImageFileName);
 531
 532   wxPNGReaderIter iter(this);
 533   FILE *fp;
 534    png_struct *png_ptr;
 535   png_info *info_ptr;
 536
 537    /* open the file */
 538   fp = fopen(filename, "wb");
 539   if (!fp)
 540     return FALSE;
 541
 542   /* allocate the necessary structures */
 543   png_ptr = new (png_struct);
 544   if (!png_ptr)
 545   {
 546     fclose(fp);
 547     return FALSE;
 548   }
 549
 550   info_ptr = new (png_info);
 551   if (!info_ptr)
 552   {
 553     fclose(fp);
 554     delete(png_ptr);
 555     return FALSE;
 556   }
 557
 558   /* set error handling */
 559   if (setjmp(png_ptr->jmpbuf))
 560   {
 561     png_write_destroy(png_ptr);
 562     fclose(fp);
 563     delete(png_ptr);
 564     delete(info_ptr);
 565
 566     /* If we get here, we had a problem reading the file */
 567     return FALSE;
 568   }
 569         //png_set_error(ima_png_error, NULL);
 570
 571 //  printf("writig pg %s ", filename);
 572    /* initialize the structures */
 573   png_info_init(info_ptr);
 574   png_write_init(png_ptr);
 575
 576   int row_stride = GetWidth() * ((GetDepth()+7)>>3);
 577   /* set up the output control */
 578    png_init_io(png_ptr, fp);
 579
 580   /* set the file information here */
 581   info_ptr->width = GetWidth();
 582   info_ptr->height = GetHeight();
 583   info_ptr->pixel_depth = GetDepth();
 584   info_ptr->channels = (GetDepth()>8) ? 3: 1;
 585   info_ptr->bit_depth = GetDepth()/info_ptr->channels;
 586   info_ptr->color_type = GetColorType();
 587   info_ptr->compression_type = info_ptr->filter_type = info_ptr->interlace_type=0;
 588   info_ptr->valid = 0;
 589   info_ptr->rowbytes = row_stride;
 590
 591
 592 // printf("P = %d D = %d RS= %d GD= %d CH= %d ", info_ptr->pixel_depth, info_ptr->bit_depth, row_stride, GetDepth(), info_ptr->channels);
 593   /* set the palette if there is one */
 594   if ((GetColorType() & COLORTYPE_PALETTE) && GetPalette())
 595   {
 596 //    printf("writing paleta[%d %d %x]",GetColorType() ,COLORTYPE_PALETTE, GetPalette());
 597     info_ptr->valid |= PNG_INFO_PLTE;
 598     info_ptr->palette = new png_color[256];
 599     info_ptr->num_palette = 256;
 600     for (int i=0; i<256; i++)
 601      GetPalette()->GetRGB(i, &info_ptr->palette[i].red, &info_ptr->palette[i].green, &info_ptr->palette[i].blue);
 602   }
 603 //    printf("Paleta [%d %d %x]",GetColorType() ,COLORTYPE_PALETTE, GetPalette());
 604
 605
 606    /* optional significant bit chunk */
 607 //   info_ptr->valid |= PNG_INFO_sBIT;
 608 //   info_ptr->sig_bit = true_bit_depth;
 609
 610   /* optional gamma chunk */
 611 //   info_ptr->valid |= PNG_INFO_gAMA;
 612 //   info_ptr->gamma = gamma;
 613
 614   /* other optional chunks */
 615
 616    /* write the file information */
 617    png_write_info(png_ptr, info_ptr);
 618
 619    /* set up the transformations you want.  Note that these are
 620       all optional.  Only call them if you want them */
 621
 622   /* shift the pixels up to a legal bit depth and fill in
 623       as appropriate to correctly scale the image */
 624 //   png_set_shift(png_ptr, &(info_ptr->sig_bit));
 625
 626   /* pack pixels into bytes */
 627 //   png_set_packing(png_ptr);
 628
 629   /* flip bgr pixels to rgb */
 630 //   png_set_bgr(png_ptr);
 631
 632    /* swap bytes of 16 bit files to most significant bit first */
 633 //   png_set_swap(png_ptr);
 634
 635    /* get rid of filler bytes, pack rgb into 3 bytes */
 636 //   png_set_rgbx(png_ptr);
 637
 638 /* If you are only writing one row at a time, this works */
 639
 640   byte *row_pointers = new byte[row_stride];
 641     iter.upset();
 642   do  {
 643 //    (unsigned char *)iter.GetRow();
 644     iter.GetRow(row_pointers, row_stride);
 645     png_write_row(png_ptr, row_pointers);
 646   } while(iter.PrevRow());
 647
 648         delete[] row_pointers;
 649
 650 /* write the rest of the file */
 651    png_write_end(png_ptr, info_ptr);
 652
 653   /* clean up after the write, and free any memory allocated */
 654    png_write_destroy(png_ptr);
 655
 656    /* if you malloced the palette, free it here */
 657    if (info_ptr->palette)
 658     delete[] (info_ptr->palette);
 659
 660   /* free the structures */
 661   delete(png_ptr);
 662   delete(info_ptr);
 663
 664   /* close the file */
 665   fclose(fp);
 666
 667   /* that's it */
 668   return TRUE;
 669 }
 670
 671 static int Power(int x, int y)
 672 {
 673     int z = 1;
 674     int i;
 675     for ( i = 0; i < y; i++)
 676     {
 677         z *= x;
 678     }
 679     return z;
 680 }
 681
 682 static char hexArray[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B',
 683   'C', 'D', 'E', 'F' };
 684
 685 static void DecToHex(int dec, char *buf)
 686 {
 687   int firstDigit = (int)(dec/16.0);
 688   int secondDigit = (int)(dec - (firstDigit*16.0));
 689   buf[0] = hexArray[firstDigit];
 690   buf[1] = hexArray[secondDigit];
 691   buf[2] = 0;
 692 }
 693
 694
 695 bool wxPNGReader::SaveXPM(char *filename, char *name)
 696 {
 697     char nameStr[256];
 698     if ( name )
 699         strcpy(nameStr, name);
 700     else
 701     {
 702         strcpy(nameStr, filename);
 703         wxStripExtension(nameStr);
 704     }
 705
 706     if ( GetDepth() > 4 )
 707     {
 708         // Only a depth of 4 and below allowed
 709         return FALSE;
 710     }
 711
 712     if ( !GetPalette() )
 713         return FALSE;
 714
 715     ofstream str(filename);
 716     if ( str.bad() )
 717         return FALSE;
 718
 719     int noColours = Power(2, GetDepth());
 720
 721     // Output header
 722     str << "/* XPM */\n";
 723     str << "static char * " << nameStr << "_xpm[] = {\n";
 724     str << "\"" << GetWidth() << " " << GetHeight() << " " << noColours << " 1\",\n";
 725
 726     // Output colourmap
 727     int base = 97 ; // start from 'a'
 728
 729     unsigned char red, green, blue;
 730     char hexBuf[4];
 731     int i;
 732     for ( i = 0; i < noColours; i ++)
 733     {
 734         str << "\"" << (char)(base + i) << "      c #";
 735         GetPalette()->GetRGB(i, &red, &green, &blue);
 736         DecToHex(red, hexBuf);
 737         str << hexBuf;
 738         DecToHex(green, hexBuf);
 739         str << hexBuf;
 740         DecToHex(blue, hexBuf);
 741         str << hexBuf;
 742         str << "\",\n";
 743     }
 744
 745     // Output the data
 746     int x, y;
 747     for ( y = 0; y < GetHeight(); y++)
 748     {
 749         str << "\"";
 750         for ( x = 0; x < GetWidth(); x++)
 751         {
 752             int index = GetIndex(x, y);
 753             str << (char)(base + index) ;
 754         }
 755         str << "\",\n";
 756     }
 757
 758     str << "};\n";
 759     str.flush();
 760
 761     return TRUE;
 762 }
 763
 764 #include <wx/msw/pnghand.h>
 765
 766 IMPLEMENT_DYNAMIC_CLASS(wxPNGFileHandler, wxBitmapHandler)
 767
 768 bool wxPNGFileHandler::LoadFile(wxBitmap *bitmap, const wxString& name, long flags,
 769     int desiredWidth, int desiredHeight)
 770 {
 771     wxPNGReader reader;
 772     if (reader.ReadFile((char*) (const char*) name))
 773     {
 774         return reader.InstantiateBitmap(bitmap);
 775     }
 776     else
 777         return FALSE;
 778 }
 779
 780 bool wxPNGFileHandler::SaveFile(wxBitmap *bitmap, const wxString& name, int type, const wxPalette *pal)
 781 {
 782     return FALSE;
 783 }
 784
 785