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/utils.h"
  38 #include "wx/msw/pngread.h"
  39 #include "wx/msw/dibutils.h"
  40
  41 extern "C" {
  42 #include "../png/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()
  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 ( wxChar* 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 #ifdef __WIN16__
 126    GlobalFreePtr((unsigned int) lpbi);
 127 #else
 128    GlobalFreePtr(lpbi);
 129 #endif
 130 //   delete Palette;
 131   }
 132   RawImage = 0;
 133   Palette = 0;
 134   lpbi = wxDibCreate(Depth, Width, Height);
 135   if (lpbi)  {
 136     RawImage = (ImagePointerType)wxDibPtr(lpbi);
 137     EfeWidth = (long)(((long)Width*Depth + 31) / 32) * 4;
 138         imageOK = TRUE;
 139   }
 140 }
 141
 142 wxPNGReader::~wxPNGReader ( )
 143 {
 144   if (lpbi)  {
 145 #ifdef __WIN16__
 146    GlobalFreePtr((unsigned int) lpbi);
 147 #else
 148    GlobalFreePtr(lpbi);
 149 #endif
 150    delete Palette;
 151   }
 152 }
 153
 154
 155 int wxPNGReader::GetIndex(int x, int y)
 156 {
 157   if (!Inside(x, y) || (Depth>8)) return -1;
 158
 159   ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 160   int index = (int)(*ImagePointer);
 161   return index;
 162 }
 163
 164 bool wxPNGReader::GetRGB(int x, int y, byte* r, byte* g, byte* b)
 165 {
 166   if (!Inside(x, y)) return FALSE;
 167
 168   if (Palette) {
 169    return Palette->GetRGB(GetIndex(x, y), r, g, b);
 170 /*   PALETTEENTRY entry;
 171    ::GetPaletteEntries((HPALETTE) Palette->GetHPALETTE(), GetIndex(x, y), 1, &entry);
 172    *r = entry.peRed;
 173    *g = entry.peGreen;
 174    *b = entry.peBlue;  */
 175   } else {
 176    ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 177    *b = ImagePointer[0];
 178    *g = ImagePointer[1];
 179    *r = ImagePointer[2];
 180   }
 181   return TRUE;
 182 }
 183
 184
 185 bool wxPNGReader::SetIndex(int x, int y, int index)
 186 {
 187   if (!Inside(x, y) || (Depth>8)) return FALSE;
 188
 189   ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 190   *ImagePointer = index;
 191
 192   return TRUE;
 193 }
 194
 195 bool wxPNGReader::SetRGB(int x, int y, byte r, byte g, byte b)
 196 {
 197   if (!Inside(x, y)) return FALSE;
 198
 199   if (ColorType & COLORTYPE_PALETTE)
 200   {
 201    if (!Palette) return FALSE;
 202    SetIndex(x, y, Palette->GetPixel(r, g, b));
 203
 204   } else {
 205    ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 206    ImagePointer[0] = b;
 207    ImagePointer[1] = g;
 208    ImagePointer[2] = r;
 209   }
 210
 211   return TRUE;
 212 }
 213
 214 bool wxPNGReader::SetPalette(wxPalette* colourmap)
 215 {
 216   if (!colourmap)
 217    return FALSE;
 218   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 219   Palette = colourmap;
 220   return (wxDibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 221 }
 222
 223 bool
 224 wxPNGReader::SetPalette(int n, byte *r, byte *g, byte *b)
 225 {
 226   Palette = new wxPalette();
 227   if (!Palette)
 228    return FALSE;
 229
 230   if (!g) g = r;
 231   if (!b) b = g;
 232   Palette->Create(n, r, g, b);
 233   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 234   return (wxDibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 235 }
 236
 237 bool
 238 wxPNGReader::SetPalette(int n, rgb_color_struct *rgb_struct)
 239 {
 240   Palette = new wxPalette();
 241   if (!Palette)
 242    return FALSE;
 243
 244   byte r[256], g[256], b[256];
 245
 246   for(int i=0; i<n; i++)
 247   {
 248    r[i] = rgb_struct[i].red;
 249    g[i] = rgb_struct[i].green;
 250    b[i] = rgb_struct[i].blue;
 251   }
 252   // Added by JACS copying from Andrew Davison's additions
 253   // to GIF-reading code
 254   // Make transparency colour black...
 255   if (bgindex != -1)
 256     r[bgindex] = g[bgindex] = b[bgindex] = 0;
 257
 258   Palette->Create(n, r, g, b);
 259   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 260   return (wxDibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 261 }
 262
 263 void wxPNGReader::NullData()
 264 {
 265   lpbi = NULL;
 266   Palette = NULL;
 267 }
 268
 269 wxBitmap* wxPNGReader::GetBitmap()
 270 {
 271     wxBitmap *bitmap = new wxBitmap;
 272     if ( InstantiateBitmap(bitmap) )
 273         return bitmap;
 274     else
 275     {
 276         delete bitmap;
 277         return NULL;
 278     }
 279 }
 280
 281 bool wxPNGReader::InstantiateBitmap(wxBitmap *bitmap)
 282 {
 283   HDC dc = ::CreateCompatibleDC(NULL);
 284
 285   if (dc)
 286   {
 287         // tmpBitmap is a dummy, to satisfy ::CreateCompatibleDC (it
 288         // is a memory dc that must have a bitmap selected into it)
 289         HDC dc2 = GetDC(NULL);
 290         HBITMAP tmpBitmap = ::CreateCompatibleBitmap(dc2, GetWidth(), GetHeight());
 291         ReleaseDC(NULL, dc2);
 292         HBITMAP oldBitmap = (HBITMAP) ::SelectObject(dc, tmpBitmap);
 293
 294         if ( Palette )
 295         {
 296             ::SelectPalette(dc, (HPALETTE) Palette->GetHPALETTE(), FALSE);
 297         ::RealizePalette(dc);
 298         }
 299
 300     HBITMAP hBitmap = ::CreateDIBitmap(dc, lpbi,
 301         CBM_INIT, RawImage, (LPBITMAPINFO) lpbi, DIB_PAL_COLORS);
 302
 303         ::SelectPalette(dc, NULL, TRUE);
 304         ::SelectObject(dc, oldBitmap);
 305         ::DeleteObject(tmpBitmap);
 306         ::DeleteDC(dc);
 307
 308         if ( hBitmap )
 309         {
 310           bitmap->SetHBITMAP((WXHBITMAP) hBitmap);
 311           bitmap->SetWidth(GetWidth());
 312           bitmap->SetHeight(GetHeight());
 313           bitmap->SetDepth(GetDepth());
 314           if ( GetDepth() > 1 && Palette )
 315             bitmap->SetPalette(*Palette);
 316 #if WXWIN_COMPATIBILITY_2
 317           bitmap->SetOk(TRUE);
 318 #endif // WXWIN_COMPATIBILITY_2
 319
 320           // Make a mask if appropriate
 321           if ( bgindex > -1 )
 322           {
 323             wxMask *mask = CreateMask();
 324             bitmap->SetMask(mask);
 325           }
 326       return TRUE;
 327         }
 328         else
 329         {
 330           return FALSE;
 331         }
 332   }
 333   else
 334     {
 335     return FALSE;
 336     }
 337 }
 338
 339 wxPalette *wxCopyPalette(const wxPalette *cmap)
 340 {
 341   // To get number of entries...
 342   WORD count = 0;
 343   ::GetObject((HPALETTE) cmap->GetHPALETTE(), sizeof(WORD), &count);
 344
 345   LOGPALETTE* logPal = (LOGPALETTE*)
 346      new BYTE[sizeof(LOGPALETTE) + count*sizeof(PALETTEENTRY)];
 347   logPal->palVersion = 0x300;
 348   logPal->palNumEntries = count;
 349   ::GetPaletteEntries((HPALETTE) cmap->GetHPALETTE(), 0, count, logPal->palPalEntry);
 350
 351   HPALETTE hPalette = ::CreatePalette(logPal);
 352   delete[] logPal;
 353
 354   wxPalette *newCmap = new wxPalette;
 355   newCmap->SetHPALETTE((WXHPALETTE) hPalette);
 356   return newCmap;
 357 }
 358
 359 wxMask *wxPNGReader::CreateMask()
 360 {
 361     HBITMAP hBitmap = ::CreateBitmap(GetWidth(), GetHeight(), 1, 1, NULL);
 362
 363   HDC dc = ::CreateCompatibleDC(NULL);
 364     HBITMAP oldBitmap = (HBITMAP) ::SelectObject(dc, hBitmap);
 365
 366     int bgIndex = GetBGIndex();
 367
 368     int x,y;
 369
 370     for (x=0; x<GetWidth(); x++)
 371     {
 372         for (y=0; y<GetHeight(); y++)
 373         {
 374             int index = GetIndex(x, y);
 375             if ( index == bgIndex )
 376                 ::SetPixel(dc, x, GetHeight() - y - 1, RGB(0, 0, 0));
 377             else
 378                 ::SetPixel(dc, x, GetHeight() - y - 1, RGB(255, 255, 255));
 379
 380       }
 381     }
 382     ::SelectObject(dc, oldBitmap);
 383     wxMask *mask = new wxMask;
 384     mask->SetMaskBitmap((WXHBITMAP) hBitmap);
 385     return mask;
 386 }
 387
 388 bool wxPNGReader::ReadFile(wxChar * ImageFileName)
 389 {
 390     if (ImageFileName)
 391         wxStrcpy(filename, ImageFileName);
 392
 393     /* open the file */
 394     FILE *fp = fopen(wxConvFile.cWX2MB(filename), "rb");
 395     if (!fp)
 396         return FALSE;
 397
 398     /* allocate the necessary structures */
 399     png_struct *png_ptr = new (png_struct);
 400     if (!png_ptr)
 401     {
 402         fclose(fp);
 403         return FALSE;
 404     }
 405
 406     png_info *info_ptr = new (png_info);
 407     if (!info_ptr)
 408     {
 409         fclose(fp);
 410         delete(png_ptr);
 411         return FALSE;
 412     }
 413
 414     /* set error handling */
 415     if (setjmp(png_ptr->jmpbuf))
 416     {
 417         png_read_destroy(png_ptr, info_ptr, (png_info *)0);
 418         fclose(fp);
 419         delete(png_ptr);
 420         delete(info_ptr);
 421
 422         /* If we get here, we had a problem reading the file */
 423         return FALSE;
 424     }
 425     //png_set_error(ima_png_error, NULL);
 426
 427     /* initialize the structures, info first for error handling */
 428     png_info_init(info_ptr);
 429     png_read_init(png_ptr);
 430
 431     /* set up the input control */
 432     png_init_io(png_ptr, fp);
 433
 434     /* read the file information */
 435     png_read_info(png_ptr, info_ptr);
 436
 437     /* allocate the memory to hold the image using the fields
 438        of png_info. */
 439     png_color_16 my_background={ 0, 31, 127, 255, 0 };
 440
 441     if (info_ptr->valid & PNG_INFO_bKGD)
 442     {
 443         png_set_background(png_ptr, &(info_ptr->background),
 444                 PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
 445         if ( info_ptr->num_palette > 0 )
 446             bgindex = info_ptr->background.index;
 447     }
 448     else   {
 449         png_set_background(png_ptr, &my_background,
 450                 PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
 451
 452         // Added by JACS: guesswork!
 453         if ( info_ptr->num_trans != 0 )
 454             bgindex = info_ptr->num_trans - 1 ;
 455     }
 456
 457     /* tell libpng to strip 16 bit depth files down to 8 bits */
 458     if (info_ptr->bit_depth == 16)
 459         png_set_strip_16(png_ptr);
 460
 461     int pixel_depth=(info_ptr->pixel_depth<24) ? info_ptr->pixel_depth: 24;
 462     Create(info_ptr->width, info_ptr->height, pixel_depth,
 463             info_ptr->color_type);
 464
 465     if (info_ptr->num_palette>0)
 466     {
 467         SetPalette((int)info_ptr->num_palette, (rgb_color_struct*)info_ptr->palette);
 468     }
 469
 470     int row_stride = info_ptr->width * ((pixel_depth+7)>>3);
 471     //  printf("P = %d D = %d RS= %d ", info_ptr->num_palette, info_ptr->pixel_depth,row_stride);
 472     //  printf("CT = %d TRS = %d BD= %d ", info_ptr->color_type, info_ptr->valid & PNG_INFO_tRNS,info_ptr->bit_depth);
 473
 474     byte *row_pointers = new byte[row_stride];
 475
 476     /* turn on interlace handling */
 477     int number_passes;
 478     if (info_ptr->interlace_type)
 479         number_passes = png_set_interlace_handling(png_ptr);
 480     else
 481         number_passes = 1;
 482     //  printf("NP = %d ", number_passes);
 483
 484     // don't use the object to prevent warnings from VC++ about "unportable
 485     // interaction between setjmp and C++ object destruction" (this is a correct
 486     // warning, of course!)
 487     wxPNGReaderIter *iter = new wxPNGReaderIter(this);
 488     for (int pass=0; pass< number_passes; pass++)
 489     {
 490         iter->upset();
 491         int y=0;
 492         do  {
 493             //(unsigned char *)iter.GetRow();
 494             if (info_ptr->interlace_type)  {
 495                 if (pass>0)
 496                     iter->GetRow(row_pointers, row_stride);
 497                 png_read_row(png_ptr, row_pointers, NULL);
 498             }
 499             else
 500                 png_read_row(png_ptr, row_pointers, NULL);
 501
 502             iter->SetRow(row_pointers, row_stride);
 503             y++;
 504         } while(iter->PrevRow());
 505         //  printf("Y=%d ",y);
 506     }
 507
 508     delete iter;
 509     delete[] row_pointers;
 510
 511     /* read the rest of the file, getting any additional chunks
 512        in info_ptr */
 513     png_read_end(png_ptr, info_ptr);
 514
 515     /* clean up after the read, and free any memory allocated */
 516     png_read_destroy(png_ptr, info_ptr, (png_info *)0);
 517
 518     /* free the structures */
 519     delete(png_ptr);
 520     delete(info_ptr);
 521
 522     /* close the file */
 523     fclose(fp);
 524
 525     /* that's it */
 526     return TRUE;
 527 }
 528
 529
 530 /* write a png file */
 531
 532 bool wxPNGReader::SaveFile(wxChar * ImageFileName)
 533 {
 534   if (ImageFileName)
 535    wxStrcpy(filename, ImageFileName);
 536
 537   wxPNGReaderIter iter(this);
 538   FILE *fp;
 539    png_struct *png_ptr;
 540   png_info *info_ptr;
 541
 542    /* open the file */
 543   fp = fopen(wxConvFile.cWX2MB(filename), "wb");
 544   if (!fp)
 545     return FALSE;
 546
 547   /* allocate the necessary structures */
 548   png_ptr = new (png_struct);
 549   if (!png_ptr)
 550   {
 551     fclose(fp);
 552     return FALSE;
 553   }
 554
 555   info_ptr = new (png_info);
 556   if (!info_ptr)
 557   {
 558     fclose(fp);
 559     delete(png_ptr);
 560     return FALSE;
 561   }
 562
 563   /* set error handling */
 564   if (setjmp(png_ptr->jmpbuf))
 565   {
 566     png_write_destroy(png_ptr);
 567     fclose(fp);
 568     delete(png_ptr);
 569     delete(info_ptr);
 570
 571     /* If we get here, we had a problem reading the file */
 572     return FALSE;
 573   }
 574         //png_set_error(ima_png_error, NULL);
 575
 576 //  printf("writig pg %s ", filename);
 577    /* initialize the structures */
 578   png_info_init(info_ptr);
 579   png_write_init(png_ptr);
 580
 581   int row_stride = GetWidth() * ((GetDepth()+7)>>3);
 582   /* set up the output control */
 583    png_init_io(png_ptr, fp);
 584
 585   /* set the file information here */
 586   info_ptr->width = GetWidth();
 587   info_ptr->height = GetHeight();
 588   info_ptr->pixel_depth = GetDepth();
 589   info_ptr->channels = (GetDepth()>8) ? 3: 1;
 590   info_ptr->bit_depth = GetDepth()/info_ptr->channels;
 591   info_ptr->color_type = GetColorType();
 592   info_ptr->compression_type = info_ptr->filter_type = info_ptr->interlace_type=0;
 593   info_ptr->valid = 0;
 594   info_ptr->rowbytes = row_stride;
 595
 596
 597 // 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);
 598   /* set the palette if there is one */
 599   if ((GetColorType() & COLORTYPE_PALETTE) && GetPalette())
 600   {
 601 //    printf("writing paleta[%d %d %x]",GetColorType() ,COLORTYPE_PALETTE, GetPalette());
 602     info_ptr->valid |= PNG_INFO_PLTE;
 603     info_ptr->palette = new png_color[256];
 604     info_ptr->num_palette = 256;
 605     for (int i=0; i<256; i++)
 606      GetPalette()->GetRGB(i, &info_ptr->palette[i].red, &info_ptr->palette[i].green, &info_ptr->palette[i].blue);
 607   }
 608 //    printf("Paleta [%d %d %x]",GetColorType() ,COLORTYPE_PALETTE, GetPalette());
 609
 610
 611    /* optional significant bit chunk */
 612 //   info_ptr->valid |= PNG_INFO_sBIT;
 613 //   info_ptr->sig_bit = true_bit_depth;
 614
 615   /* optional gamma chunk */
 616 //   info_ptr->valid |= PNG_INFO_gAMA;
 617 //   info_ptr->gamma = gamma;
 618
 619   /* other optional chunks */
 620
 621    /* write the file information */
 622    png_write_info(png_ptr, info_ptr);
 623
 624    /* set up the transformations you want.  Note that these are
 625       all optional.  Only call them if you want them */
 626
 627   /* shift the pixels up to a legal bit depth and fill in
 628       as appropriate to correctly scale the image */
 629 //   png_set_shift(png_ptr, &(info_ptr->sig_bit));
 630
 631   /* pack pixels into bytes */
 632 //   png_set_packing(png_ptr);
 633
 634   /* flip bgr pixels to rgb */
 635 //   png_set_bgr(png_ptr);
 636
 637    /* swap bytes of 16 bit files to most significant bit first */
 638 //   png_set_swap(png_ptr);
 639
 640    /* get rid of filler bytes, pack rgb into 3 bytes */
 641 //   png_set_rgbx(png_ptr);
 642
 643 /* If you are only writing one row at a time, this works */
 644
 645   byte *row_pointers = new byte[row_stride];
 646     iter.upset();
 647   do  {
 648 //    (unsigned char *)iter.GetRow();
 649     iter.GetRow(row_pointers, row_stride);
 650     png_write_row(png_ptr, row_pointers);
 651   } while(iter.PrevRow());
 652
 653         delete[] row_pointers;
 654
 655 /* write the rest of the file */
 656    png_write_end(png_ptr, info_ptr);
 657
 658   /* clean up after the write, and free any memory allocated */
 659    png_write_destroy(png_ptr);
 660
 661    /* if you malloced the palette, free it here */
 662    if (info_ptr->palette)
 663     delete[] (info_ptr->palette);
 664
 665   /* free the structures */
 666   delete(png_ptr);
 667   delete(info_ptr);
 668
 669   /* close the file */
 670   fclose(fp);
 671
 672   /* that's it */
 673   return TRUE;
 674 }
 675
 676 static int Power(int x, int y)
 677 {
 678     int z = 1;
 679     int i;
 680     for ( i = 0; i < y; i++)
 681     {
 682         z *= x;
 683     }
 684     return z;
 685 }
 686
 687 static char hexArray[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B',
 688   'C', 'D', 'E', 'F' };
 689
 690 static void DecToHex(int dec, char *buf)
 691 {
 692   int firstDigit = (int)(dec/16.0);
 693   int secondDigit = (int)(dec - (firstDigit*16.0));
 694   buf[0] = hexArray[firstDigit];
 695   buf[1] = hexArray[secondDigit];
 696   buf[2] = 0;
 697 }
 698
 699
 700 bool wxPNGReader::SaveXPM(wxChar *filename, wxChar *name)
 701 {
 702     wxChar nameStr[256];
 703     if ( name )
 704         wxStrcpy(nameStr, name);
 705     else
 706     {
 707         wxStrcpy(nameStr, filename);
 708         wxStripExtension(nameStr);
 709     }
 710
 711     if ( GetDepth() > 4 )
 712     {
 713         // Only a depth of 4 and below allowed
 714         return FALSE;
 715     }
 716
 717     if ( !GetPalette() )
 718         return FALSE;
 719
 720     ofstream str(wxConvFile.cWX2MB(filename));
 721     if ( str.bad() )
 722         return FALSE;
 723
 724     int noColours = Power(2, GetDepth());
 725
 726     // Output header
 727     str << "/* XPM */\n";
 728     str << "static char * " << nameStr << "_xpm[] = {\n";
 729     str << "\"" << GetWidth() << " " << GetHeight() << " " << noColours << " 1\",\n";
 730
 731     // Output colourmap
 732     int base = 97 ; // start from 'a'
 733
 734     unsigned char red, green, blue;
 735     char hexBuf[4];
 736     int i;
 737     for ( i = 0; i < noColours; i ++)
 738     {
 739         str << "\"" << (char)(base + i) << "      c #";
 740         GetPalette()->GetRGB(i, &red, &green, &blue);
 741         DecToHex(red, hexBuf);
 742         str << hexBuf;
 743         DecToHex(green, hexBuf);
 744         str << hexBuf;
 745         DecToHex(blue, hexBuf);
 746         str << hexBuf;
 747         str << "\",\n";
 748     }
 749
 750     // Output the data
 751     int x, y;
 752     for ( y = 0; y < GetHeight(); y++)
 753     {
 754         str << "\"";
 755         for ( x = 0; x < GetWidth(); x++)
 756         {
 757             int index = GetIndex(x, y);
 758             str << (char)(base + index) ;
 759         }
 760         str << "\",\n";
 761     }
 762
 763     str << "};\n";
 764     str.flush();
 765
 766     return TRUE;
 767 }
 768
 769 #include "wx/msw/pnghand.h"
 770
 771 IMPLEMENT_DYNAMIC_CLASS(wxPNGFileHandler, wxBitmapHandler)
 772
 773 bool wxPNGFileHandler::LoadFile(wxBitmap *bitmap, const wxString& name, long flags,
 774     int desiredWidth, int desiredHeight)
 775 {
 776     wxPNGReader reader;
 777     if (reader.ReadFile(WXSTRINGCAST name))
 778     {
 779         return reader.InstantiateBitmap(bitmap);
 780     }
 781     else
 782         return FALSE;
 783 }
 784
 785 bool wxPNGFileHandler::SaveFile(wxBitmap *bitmap, const wxString& name, int type, const wxPalette *pal)
 786 {
 787     return FALSE;
 788 }
 789
 790