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