src/mac/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/mac/pnghand.h>
  38 #include <wx/mac/pngread.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 extern CTabHandle wxMacCreateColorTable( int numColors ) ;
  48 extern void wxMacDestroyColorTable( CTabHandle colors )  ;
  49 extern void wxMacSetColorTableEntry( CTabHandle newColors , int index , int red , int green ,  int blue ) ;
  50 extern GWorldPtr wxMacCreateGWorld( int height , int width , int depth ) ;
  51 extern void wxMacDestroyGWorld( GWorldPtr gw ) ;
  52
  53 void
  54 ima_png_error(png_struct *png_ptr, char *message)
  55 {
  56         wxMessageBox(message, "PNG error");
  57   longjmp(png_ptr->jmpbuf, 1);
  58 }
  59
  60
  61 // static wxGifReaderIter* iter;
  62 wxPalette *wxCopyPalette(const wxPalette *cmap);
  63
  64 wxPNGReader::wxPNGReader(void)
  65 {
  66   filetype = 0;
  67   RawImage = NULL;      //  Image data
  68
  69   Width = 0; Height = 0;       //  Dimensions
  70   Depth = 0;           // (bits x pixel)
  71   ColorType = 0;        // Bit 1 = Palette used
  72                   // Bit 2 = Color used
  73                   // Bit 3 = Alpha used
  74
  75   EfeWidth = 0;         // Efective Width
  76
  77   lpbi = NULL;
  78   bgindex = -1;
  79   Palette = 0;
  80   imageOK = FALSE;
  81 }
  82
  83 wxPNGReader::wxPNGReader ( char* ImageFileName )
  84 {
  85   imageOK = FALSE;
  86   filetype = 0;
  87   RawImage = NULL;      //  Image data
  88
  89   Width = 0; Height = 0;       //  Dimensions
  90   Depth = 0;           // (bits x pixel)
  91   ColorType = 0;        // Bit 1 = Palette used
  92                   // Bit 2 = Color used
  93                   // Bit 3 = Alpha used
  94
  95   EfeWidth = 0;         // Efective Width
  96
  97   lpbi = NULL;
  98   bgindex = -1;
  99   Palette = 0;
 100
 101   imageOK = ReadFile (ImageFileName);
 102 }
 103
 104 void
 105 wxPNGReader::Create(int width, int height, int depth, int colortype)
 106 {
 107   Width = width; Height = height; Depth = depth;
 108   ColorType = (colortype>=0) ? colortype: ((Depth>8) ? COLORTYPE_COLOR: 0);
 109   delete Palette;
 110   delete[] RawImage ;
 111   RawImage = 0;
 112   Palette = 0;
 113
 114   if (lpbi)
 115   {
 116         wxMacDestroyGWorld( lpbi ) ;
 117   }
 118   if (lpbi = wxMacCreateGWorld( Width , Height , Depth) )
 119   {
 120     EfeWidth = (long)(((long)Width*Depth + 31) / 32) * 4;
 121     int bitwidth = width ;
 122     if ( EfeWidth > bitwidth )
 123         bitwidth = EfeWidth ;
 124
 125                 RawImage = (byte*) new char[ ( bitwidth * Height * ((Depth+7)>>3) ) ];
 126     imageOK = TRUE;
 127   }
 128 }
 129
 130 wxPNGReader::~wxPNGReader ( )
 131 {
 132         delete[] RawImage ;
 133   if (lpbi)  {
 134         wxMacDestroyGWorld( lpbi ) ;
 135   }
 136   delete Palette;
 137 }
 138
 139
 140 int wxPNGReader::GetIndex(int x, int y)
 141 {
 142   if (!Inside(x, y) || (Depth>8)) return -1;
 143
 144   ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 145   int index = (int)(*ImagePointer);
 146   return index;
 147 }
 148
 149 bool wxPNGReader::GetRGB(int x, int y, byte* r, byte* g, byte* b)
 150 {
 151   if (!Inside(x, y)) return FALSE;
 152
 153   if (Palette) {
 154    return Palette->GetRGB(GetIndex(x, y), r, g, b);
 155 /*   PALETTEENTRY entry;
 156    ::GetPaletteEntries((HPALETTE) Palette->GetHPALETTE(), GetIndex(x, y), 1, &entry);
 157    *r = entry.peRed;
 158    *g = entry.peGreen;
 159    *b = entry.peBlue;  */
 160   } else {
 161    ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 162    *b = ImagePointer[0];
 163    *g = ImagePointer[1];
 164    *r = ImagePointer[2];
 165   }
 166   return TRUE;
 167 }
 168
 169
 170 bool wxPNGReader::SetIndex(int x, int y, int index)
 171 {
 172   if (!Inside(x, y) || (Depth>8)) return FALSE;
 173
 174   ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 175   *ImagePointer = index;
 176
 177   return TRUE;
 178 }
 179
 180 bool wxPNGReader::SetRGB(int x, int y, byte r, byte g, byte b)
 181 {
 182   if (!Inside(x, y)) return FALSE;
 183
 184   if (ColorType & COLORTYPE_PALETTE)
 185   {
 186    if (!Palette) return FALSE;
 187    SetIndex(x, y, Palette->GetPixel(r, g, b));
 188
 189   } else {
 190    ImagePointerType ImagePointer = RawImage + EfeWidth*y + (x*Depth >> 3);
 191    ImagePointer[0] = b;
 192    ImagePointer[1] = g;
 193    ImagePointer[2] = r;
 194   }
 195
 196   return TRUE;
 197 }
 198
 199 bool wxPNGReader::SetPalette(wxPalette* colourmap)
 200 {
 201   delete Palette ;
 202   if (!colourmap)
 203    return FALSE;
 204   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 205   Palette = new wxPalette( *colourmap );
 206         return true ;
 207 //  return (DibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 208 }
 209
 210 bool
 211 wxPNGReader::SetPalette(int n, byte *r, byte *g, byte *b)
 212 {
 213   delete Palette ;
 214   Palette = new wxPalette();
 215   if (!Palette)
 216    return FALSE;
 217
 218   if (!g) g = r;
 219   if (!b) b = g;
 220   Palette->Create(n, r, g, b);
 221   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 222         return true ;
 223 //    return (DibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 224 }
 225
 226 bool
 227 wxPNGReader::SetPalette(int n, rgb_color_struct *rgb_struct)
 228 {
 229   delete Palette ;
 230   Palette = new wxPalette();
 231   if (!Palette)
 232    return FALSE;
 233
 234   byte r[256], g[256], b[256];
 235
 236   for(int i=0; i<n; i++)
 237   {
 238    r[i] = rgb_struct[i].red;
 239    g[i] = rgb_struct[i].green;
 240    b[i] = rgb_struct[i].blue;
 241   }
 242   // Added by JACS copying from Andrew Davison's additions
 243   // to GIF-reading code
 244   // Make transparency colour black...
 245   if (bgindex != -1)
 246     r[bgindex] = g[bgindex] = b[bgindex] = 0;
 247
 248   Palette->Create(n, r, g, b);
 249   ColorType |= (COLORTYPE_PALETTE | COLORTYPE_COLOR);
 250         return true ;
 251 //    return (DibSetUsage(lpbi, (HPALETTE) Palette->GetHPALETTE(), WXIMA_COLORS ) != 0);
 252 }
 253
 254 void wxPNGReader::NullData()
 255 {
 256   if (lpbi)  {
 257         wxMacDestroyGWorld( lpbi ) ;
 258   }
 259   delete Palette;
 260   lpbi = NULL;
 261   Palette = NULL;
 262 }
 263
 264 wxBitmap* wxPNGReader::GetBitmap(void)
 265 {
 266     wxBitmap *bitmap = new wxBitmap;
 267     if ( InstantiateBitmap(bitmap) )
 268         return bitmap;
 269     else
 270     {
 271         delete bitmap;
 272         return NULL;
 273     }
 274 }
 275
 276 bool wxPNGReader::InstantiateBitmap(wxBitmap *bitmap)
 277 {
 278     if ( lpbi )
 279     {
 280       bitmap->SetHBITMAP((WXHBITMAP) lpbi);
 281       bitmap->SetWidth(GetWidth());
 282       bitmap->SetHeight(GetHeight());
 283       bitmap->SetDepth(GetDepth());
 284       if ( GetDepth() > 1 && Palette )
 285         bitmap->SetPalette(*Palette);
 286       bitmap->SetOk(TRUE);
 287
 288
 289       // Make a mask if appropriate
 290       /*
 291       if ( bgindex > -1 )
 292       {
 293         wxMask *mask = CreateMask();
 294         bitmap->SetMask(mask);
 295       }
 296       */
 297       lpbi = NULL ; // bitmap has taken over ownership
 298                 return TRUE;
 299     }
 300     else
 301     {
 302       return FALSE;
 303     }
 304 /*
 305   HDC dc = ::CreateCompatibleDC(NULL);
 306
 307   if (dc)
 308   {
 309         // tmpBitmap is a dummy, to satisfy ::CreateCompatibleDC (it
 310         // is a memory dc that must have a bitmap selected into it)
 311         HDC dc2 = GetDC(NULL);
 312         HBITMAP tmpBitmap = ::CreateCompatibleBitmap(dc2, GetWidth(), GetHeight());
 313         ReleaseDC(NULL, dc2);
 314         HBITMAP oldBitmap = (HBITMAP) ::SelectObject(dc, tmpBitmap);
 315
 316         if ( Palette )
 317         {
 318             HPALETTE oldPal = ::SelectPalette(dc, (HPALETTE) Palette->GetHPALETTE(), FALSE);
 319         ::RealizePalette(dc);
 320         }
 321
 322     HBITMAP hBitmap = ::CreateDIBitmap(dc, lpbi,
 323         CBM_INIT, RawImage, (LPBITMAPINFO) lpbi, DIB_PAL_COLORS);
 324
 325         ::SelectPalette(dc, NULL, TRUE);
 326         ::SelectObject(dc, oldBitmap);
 327         ::DeleteObject(tmpBitmap);
 328         ::DeleteDC(dc);
 329
 330         if ( hBitmap )
 331         {
 332           bitmap->SetHBITMAP((WXHBITMAP) hBitmap);
 333           bitmap->SetWidth(GetWidth());
 334           bitmap->SetHeight(GetHeight());
 335           bitmap->SetDepth(GetDepth());
 336           if ( GetDepth() > 1 && Palette )
 337             bitmap->SetPalette(*Palette);
 338           bitmap->SetOk(TRUE);
 339
 340
 341           // Make a mask if appropriate
 342           if ( bgindex > -1 )
 343           {
 344             wxMask *mask = CreateMask();
 345             bitmap->SetMask(mask);
 346           }
 347       return TRUE;
 348         }
 349         else
 350         {
 351           return FALSE;
 352         }
 353   }
 354   else
 355     {
 356     return FALSE;
 357     }
 358   */
 359   return false ;
 360 }
 361
 362 wxPalette *wxCopyPalette(const wxPalette *cmap)
 363 {
 364   wxPalette *newCmap = new wxPalette( *cmap ) ;
 365   return newCmap;
 366 }
 367
 368 wxMask *wxPNGReader::CreateMask(void)
 369 {
 370 /*
 371     HBITMAP hBitmap = ::CreateBitmap(GetWidth(), GetHeight(), 1, 1, NULL);
 372
 373   HDC dc = ::CreateCompatibleDC(NULL);
 374     HBITMAP oldBitmap = (HBITMAP) ::SelectObject(dc, hBitmap);
 375
 376     int bgIndex = GetBGIndex();
 377
 378     int x,y;
 379
 380     for (x=0; x<GetWidth(); x++)
 381     {
 382         for (y=0; y<GetHeight(); y++)
 383         {
 384             int index = GetIndex(x, y);
 385             if ( index == bgIndex )
 386                 ::SetPixel(dc, x, GetHeight() - y - 1, RGB(0, 0, 0));
 387             else
 388                 ::SetPixel(dc, x, GetHeight() - y - 1, RGB(255, 255, 255));
 389
 390       }
 391     }
 392     ::SelectObject(dc, oldBitmap);
 393     wxMask *mask = new wxMask;
 394     mask->SetMaskBitmap((WXHBITMAP) hBitmap);
 395     return mask;
 396    */
 397    return NULL ;
 398 }
 399
 400 bool wxPNGReader::ReadFile(char * ImageFileName)
 401 {
 402   int number_passes;
 403
 404   if (ImageFileName)
 405    strcpy(filename, ImageFileName);
 406
 407   FILE *fp;
 408   png_struct *png_ptr;
 409    png_info *info_ptr;
 410   wxPNGReaderIter iter(this);
 411
 412   /* open the file */
 413   fp = fopen(wxUnix2MacFilename( ImageFileName ), "rb");
 414   if (!fp)
 415     return FALSE;
 416
 417   /* allocate the necessary structures */
 418   png_ptr = new (png_struct);
 419   if (!png_ptr)
 420   {
 421     fclose(fp);
 422     return FALSE;
 423   }
 424
 425   info_ptr = new (png_info);
 426   if (!info_ptr)
 427   {
 428     fclose(fp);
 429     delete(png_ptr);
 430     return FALSE;
 431   }
 432   /* set error handling */
 433   if (setjmp(png_ptr->jmpbuf))
 434   {
 435     png_read_destroy(png_ptr, info_ptr, (png_info *)0);
 436     fclose(fp);
 437     delete(png_ptr);
 438     delete(info_ptr);
 439
 440     /* If we get here, we had a problem reading the file */
 441     return FALSE;
 442   }
 443         //png_set_error(ima_png_error, NULL);
 444
 445   /* initialize the structures, info first for error handling */
 446   png_info_init(info_ptr);
 447   png_read_init(png_ptr);
 448
 449   /* set up the input control */
 450   png_init_io(png_ptr, fp);
 451
 452   /* read the file information */
 453   png_read_info(png_ptr, info_ptr);
 454
 455   /* allocate the memory to hold the image using the fields
 456     of png_info. */
 457   png_color_16 my_background={ 0, 31, 127, 255, 0 };
 458
 459   if (info_ptr->valid & PNG_INFO_bKGD)
 460     {
 461     png_set_background(png_ptr, &(info_ptr->background),
 462       PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
 463         if ( info_ptr->num_palette > 0 )
 464             bgindex = info_ptr->background.index;
 465     }
 466   else   {
 467     png_set_background(png_ptr, &my_background,
 468       PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
 469
 470         // Added by JACS: guesswork!
 471         if ( info_ptr->num_trans != 0 )
 472             bgindex = info_ptr->num_trans - 1 ;
 473    }
 474
 475   /* tell libpng to strip 16 bit depth files down to 8 bits */
 476   if (info_ptr->bit_depth == 16)
 477     png_set_strip_16(png_ptr);
 478
 479   int pixel_depth=(info_ptr->pixel_depth<24) ? info_ptr->pixel_depth: 24;
 480   Create(info_ptr->width, info_ptr->height, pixel_depth,
 481     info_ptr->color_type);
 482
 483   if (info_ptr->num_palette>0)
 484     {
 485       SetPalette((int)info_ptr->num_palette, (rgb_color_struct*)info_ptr->palette);
 486     }
 487
 488   int row_stride = info_ptr->width * ((pixel_depth+7)>>3);
 489  //  printf("P = %d D = %d RS= %d ", info_ptr->num_palette, info_ptr->pixel_depth,row_stride);
 490 //  printf("CT = %d TRS = %d BD= %d ", info_ptr->color_type, info_ptr->valid & PNG_INFO_tRNS,info_ptr->bit_depth);
 491
 492   byte *row_pointers = new byte[row_stride];
 493
 494   /* turn on interlace handling */
 495   if (info_ptr->interlace_type)
 496     number_passes = png_set_interlace_handling(png_ptr);
 497   else
 498     number_passes = 1;
 499 //  printf("NP = %d ", number_passes);
 500
 501   for (int pass=0; pass< number_passes; pass++)
 502   {
 503           iter.upset();
 504           int y=0;
 505                 CGrafPtr        origPort ;
 506                 GDHandle        origDevice ;
 507
 508                 GetGWorld( &origPort , &origDevice ) ;
 509                 // ignore shapedc
 510                 SetGWorld( lpbi , NULL ) ;
 511           do
 512           {
 513         //    (unsigned char *)iter.GetRow();
 514             if (info_ptr->interlace_type)
 515             {
 516              if (pass>0)
 517               iter.GetRow(row_pointers, row_stride);
 518              png_read_row(png_ptr, row_pointers, NULL);
 519             }
 520             else
 521              png_read_row(png_ptr, row_pointers, NULL);
 522
 523                         if ( info_ptr->palette )
 524                         {
 525                                 if ( pixel_depth == 8 )
 526                                 {
 527                                         for ( int i = 0 ; i < info_ptr->width ; ++i )
 528                                         {
 529                                                 png_color_struct* color ;
 530                                                 RGBColor col ;
 531
 532                                                 int index = row_pointers[i] ;
 533                                                 color = &info_ptr->palette[index] ;
 534                                                 col.red = (((int)color->red) << 8) | ((int)color->red) ;
 535                                                 col.green = (((int)color->green) << 8) | ((int)color->green) ;
 536                                                 col.blue = (((int)color->blue) << 8) | ((int)color->blue) ;
 537                                                 SetCPixel( i, y, &col);
 538                                         }
 539                                         /*
 540                                         png_color_struct* color ;
 541                                         RGBColor col ;
 542                                         unsigned char* p = &row_pointers[0] ;
 543                                         PenNormal() ;
 544                                         MoveTo( 0 , y ) ;
 545                                         int index = *p ;
 546                                         color = &info_ptr->palette[index] ;
 547                                         col.red = (color->red << 8) | color->red ;
 548                                         col.green = (color->green << 8) | color->green ;
 549                                         col.blue = (color->blue << 8) | color->blue ;
 550                                         RGBForeColor( &col ) ;
 551                                         col.red = col.green = col.blue = 0xFFFF ;
 552                                         RGBBackColor( &col ) ;
 553                                         for ( int i = 0 ; i < info_ptr->width ; ++i , ++p)
 554                                         {
 555                                                 if ( *p != index )
 556                                                 {
 557                                                         LineTo( i , y ) ;
 558                                                         index = *p ;
 559                                                         color = &info_ptr->palette[index] ;
 560                                                         col.red = (((int)color->red) << 8) | ((int)color->red) ;
 561                                                         col.green = (((int)color->green) << 8) | ((int)color->green) ;
 562                                                         col.blue = (((int)color->blue) << 8) | ((int)color->blue) ;
 563                                                         RGBForeColor( &col ) ;
 564                                                 }
 565                                         }
 566                                         LineTo( info_ptr->width  , y ) ;
 567                                         */
 568                                 }
 569                                 else
 570                                 {
 571                                         for ( int i = 0 ; i < info_ptr->width ; ++i )
 572                                         {
 573                                                 png_color_struct* color ;
 574                                                 RGBColor col ;
 575
 576                                                 int byte = ( i * pixel_depth ) / 8 ;
 577                                                 int offset = ( 8 - pixel_depth ) - ( i * pixel_depth ) % 8 ;
 578
 579                                                 int index = ( row_pointers[byte] >> offset ) & ( 0xFF >> ( 8 - pixel_depth ) );
 580                                                 color = &info_ptr->palette[index] ;
 581                                                 col.red = (((int)color->red) << 8) | ((int)color->red) ;
 582                                                 col.green = (((int)color->green) << 8) | ((int)color->green) ;
 583                                                 col.blue = (((int)color->blue) << 8) | ((int)color->blue) ;
 584                                                 SetCPixel( i, y, &col);
 585                                         }
 586                                 }
 587                         }
 588                         else
 589                         {
 590                                 for ( int i = 0 ; i < info_ptr->width ; ++i )
 591                                 {
 592                                         png_color_struct* color ;
 593                                         RGBColor col ;
 594                                         color =(png_color_struct*) (&row_pointers[i*3]) ;
 595                                         col.red = (((int)color->red) << 8) | ((int)color->red) ;
 596                                         col.green = (((int)color->green) << 8) | ((int)color->green) ;
 597                                         col.blue = (((int)color->blue) << 8) | ((int)color->blue) ;
 598                                         SetCPixel( i, y, &col);
 599                                 }
 600                         }
 601                         if (number_passes)
 602                                 iter.SetRow(row_pointers, row_stride);
 603             y++;
 604           }
 605           while(iter.PrevRow());
 606           SetGWorld( origPort , origDevice ) ;
 607
 608 //  printf("Y=%d ",y);
 609   }
 610   delete[] row_pointers;
 611
 612   /* read the rest of the file, getting any additional chunks
 613     in info_ptr */
 614   png_read_end(png_ptr, info_ptr);
 615
 616   /* clean up after the read, and free any memory allocated */
 617   png_read_destroy(png_ptr, info_ptr, (png_info *)0);
 618
 619   /* free the structures */
 620   delete(png_ptr);
 621   delete(info_ptr);
 622
 623   /* close the file */
 624   fclose(fp);
 625
 626   /* that's it */
 627   return TRUE;
 628 }
 629
 630
 631 /* write a png file */
 632
 633 bool wxPNGReader::SaveFile(char * ImageFileName)
 634 {
 635   if (ImageFileName)
 636    strcpy(filename, ImageFileName);
 637
 638   wxPNGReaderIter iter(this);
 639   FILE *fp;
 640    png_struct *png_ptr;
 641   png_info *info_ptr;
 642
 643    /* open the file */
 644   fp = fopen(filename, "wb");
 645   if (!fp)
 646     return FALSE;
 647
 648   /* allocate the necessary structures */
 649   png_ptr = new (png_struct);
 650   if (!png_ptr)
 651   {
 652     fclose(fp);
 653     return FALSE;
 654   }
 655
 656   info_ptr = new (png_info);
 657   if (!info_ptr)
 658   {
 659     fclose(fp);
 660     delete(png_ptr);
 661     return FALSE;
 662   }
 663
 664   /* set error handling */
 665   if (setjmp(png_ptr->jmpbuf))
 666   {
 667     png_write_destroy(png_ptr);
 668     fclose(fp);
 669     delete(png_ptr);
 670     delete(info_ptr);
 671
 672     /* If we get here, we had a problem reading the file */
 673     return FALSE;
 674   }
 675         //png_set_error(ima_png_error, NULL);
 676
 677 //  printf("writig pg %s ", filename);
 678    /* initialize the structures */
 679   png_info_init(info_ptr);
 680   png_write_init(png_ptr);
 681
 682   int row_stride = GetWidth() * ((GetDepth()+7)>>3);
 683   /* set up the output control */
 684    png_init_io(png_ptr, fp);
 685
 686   /* set the file information here */
 687   info_ptr->width = GetWidth();
 688   info_ptr->height = GetHeight();
 689   info_ptr->pixel_depth = GetDepth();
 690   info_ptr->channels = (GetDepth()>8) ? 3: 1;
 691   info_ptr->bit_depth = GetDepth()/info_ptr->channels;
 692   info_ptr->color_type = GetColorType();
 693   info_ptr->compression_type = info_ptr->filter_type = info_ptr->interlace_type=0;
 694   info_ptr->valid = 0;
 695   info_ptr->rowbytes = row_stride;
 696
 697
 698 // 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);
 699   /* set the palette if there is one */
 700   if ((GetColorType() & COLORTYPE_PALETTE) && GetPalette())
 701   {
 702 //    printf("writing paleta[%d %d %x]",GetColorType() ,COLORTYPE_PALETTE, GetPalette());
 703     info_ptr->valid |= PNG_INFO_PLTE;
 704     info_ptr->palette = new png_color[256];
 705     info_ptr->num_palette = 256;
 706     for (int i=0; i<256; i++)
 707      GetPalette()->GetRGB(i, &info_ptr->palette[i].red, &info_ptr->palette[i].green, &info_ptr->palette[i].blue);
 708   }
 709 //    printf("Paleta [%d %d %x]",GetColorType() ,COLORTYPE_PALETTE, GetPalette());
 710
 711
 712    /* optional significant bit chunk */
 713 //   info_ptr->valid |= PNG_INFO_sBIT;
 714 //   info_ptr->sig_bit = true_bit_depth;
 715
 716   /* optional gamma chunk */
 717 //   info_ptr->valid |= PNG_INFO_gAMA;
 718 //   info_ptr->gamma = gamma;
 719
 720   /* other optional chunks */
 721
 722    /* write the file information */
 723    png_write_info(png_ptr, info_ptr);
 724
 725    /* set up the transformations you want.  Note that these are
 726       all optional.  Only call them if you want them */
 727
 728   /* shift the pixels up to a legal bit depth and fill in
 729       as appropriate to correctly scale the image */
 730 //   png_set_shift(png_ptr, &(info_ptr->sig_bit));
 731
 732   /* pack pixels into bytes */
 733 //   png_set_packing(png_ptr);
 734
 735   /* flip bgr pixels to rgb */
 736 //   png_set_bgr(png_ptr);
 737
 738    /* swap bytes of 16 bit files to most significant bit first */
 739 //   png_set_swap(png_ptr);
 740
 741    /* get rid of filler bytes, pack rgb into 3 bytes */
 742 //   png_set_rgbx(png_ptr);
 743
 744 /* If you are only writing one row at a time, this works */
 745
 746   byte *row_pointers = new byte[row_stride];
 747     iter.upset();
 748   do  {
 749 //    (unsigned char *)iter.GetRow();
 750     iter.GetRow(row_pointers, row_stride);
 751     png_write_row(png_ptr, row_pointers);
 752   } while(iter.PrevRow());
 753
 754         delete[] row_pointers;
 755
 756 /* write the rest of the file */
 757    png_write_end(png_ptr, info_ptr);
 758
 759   /* clean up after the write, and free any memory allocated */
 760    png_write_destroy(png_ptr);
 761
 762    /* if you malloced the palette, free it here */
 763    if (info_ptr->palette)
 764     delete[] (info_ptr->palette);
 765
 766   /* free the structures */
 767   delete(png_ptr);
 768   delete(info_ptr);
 769
 770   /* close the file */
 771   fclose(fp);
 772
 773   /* that's it */
 774   return TRUE;
 775 }
 776
 777 static int Power(int x, int y)
 778 {
 779     int z = 1;
 780     int i;
 781     for ( i = 0; i < y; i++)
 782     {
 783         z *= x;
 784     }
 785     return z;
 786 }
 787
 788 static char hexArray[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B',
 789   'C', 'D', 'E', 'F' };
 790
 791 static void DecToHex(int dec, char *buf)
 792 {
 793   int firstDigit = (int)(dec/16.0);
 794   int secondDigit = (int)(dec - (firstDigit*16.0));
 795   buf[0] = hexArray[firstDigit];
 796   buf[1] = hexArray[secondDigit];
 797   buf[2] = 0;
 798 }
 799
 800
 801 bool wxPNGReader::SaveXPM(char *filename, char *name)
 802 {
 803     char nameStr[256];
 804     if ( name )
 805         strcpy(nameStr, name);
 806     else
 807     {
 808         strcpy(nameStr, filename);
 809         wxStripExtension(nameStr);
 810     }
 811
 812     if ( GetDepth() > 4 )
 813     {
 814         // Only a depth of 4 and below allowed
 815         return FALSE;
 816     }
 817
 818     if ( !GetPalette() )
 819         return FALSE;
 820
 821     ofstream str(filename);
 822     if ( str.bad() )
 823         return FALSE;
 824
 825     int noColours = Power(2, GetDepth());
 826
 827     // Output header
 828     str << "/* XPM */\n";
 829     str << "static char * " << nameStr << "_xpm[] = {\n";
 830     str << "\"" << GetWidth() << " " << GetHeight() << " " << noColours << " 1\",\n";
 831
 832     // Output colourmap
 833     int base = 97 ; // start from 'a'
 834
 835     unsigned char red, green, blue;
 836     char hexBuf[4];
 837     int i;
 838     for ( i = 0; i < noColours; i ++)
 839     {
 840         str << "\"" << (char)(base + i) << "      c #";
 841         GetPalette()->GetRGB(i, &red, &green, &blue);
 842         DecToHex(red, hexBuf);
 843         str << hexBuf;
 844         DecToHex(green, hexBuf);
 845         str << hexBuf;
 846         DecToHex(blue, hexBuf);
 847         str << hexBuf;
 848         str << "\",\n";
 849     }
 850
 851     // Output the data
 852     int x, y;
 853     for ( y = 0; y < GetHeight(); y++)
 854     {
 855         str << "\"";
 856         for ( x = 0; x < GetWidth(); x++)
 857         {
 858             int index = GetIndex(x, y);
 859             str << (char)(base + index) ;
 860         }
 861         str << "\",\n";
 862     }
 863
 864     str << "};\n";
 865     str.flush();
 866
 867     return TRUE;
 868 }
 869
 870
 871 IMPLEMENT_DYNAMIC_CLASS(wxPNGFileHandler, wxBitmapHandler)
 872
 873 bool wxPNGFileHandler::LoadFile(wxBitmap *bitmap, const wxString& name, long flags,
 874     int desiredWidth, int desiredHeight)
 875 {
 876     wxPNGReader reader;
 877     if (reader.ReadFile((char*) (const char*) name))
 878     {
 879         return reader.InstantiateBitmap(bitmap);
 880     }
 881     else
 882         return FALSE;
 883 }
 884
 885 bool wxPNGFileHandler::SaveFile(wxBitmap *bitmap, const wxString& name, int type, const wxPalette *pal)
 886 {
 887     return FALSE;
 888 }
 889
 890