src/common/image.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        image.cpp
   3 // Purpose:     wxImage
   4 // Author:      Robert Roebling
   5 // RCS-ID:      $Id$
   6 // Copyright:   (c) Robert Roebling
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 #ifdef __GNUG__
  11 #pragma implementation "image.h"
  12 #endif
  13
  14 // For compilers that support precompilation, includes "wx.h".
  15 #include "wx/wxprec.h"
  16
  17 #ifdef __BORLANDC__
  18     #pragma hdrstop
  19 #endif
  20
  21 #include "wx/defs.h"
  22
  23 #if wxUSE_IMAGE
  24
  25 #include "wx/image.h"
  26 #include "wx/bitmap.h"
  27 #include "wx/debug.h"
  28 #include "wx/log.h"
  29 #include "wx/app.h"
  30 #include "wx/filefn.h"
  31 #include "wx/wfstream.h"
  32 #include "wx/intl.h"
  33 #include "wx/module.h"
  34
  35 // For memcpy
  36 #include <string.h>
  37 #include <math.h>
  38
  39 #ifdef __SALFORDC__
  40     #undef FAR
  41 #endif
  42
  43
  44 //-----------------------------------------------------------------------------
  45 // wxImage
  46 //-----------------------------------------------------------------------------
  47
  48 class wxImageRefData: public wxObjectRefData
  49 {
  50 public:
  51     wxImageRefData();
  52     ~wxImageRefData();
  53
  54     int             m_width;
  55     int             m_height;
  56     unsigned char  *m_data;
  57     bool            m_hasMask;
  58     unsigned char   m_maskRed,m_maskGreen,m_maskBlue;
  59     bool            m_ok;
  60     bool            m_static;
  61 #if wxUSE_PALETTE
  62     wxPalette       m_palette;
  63 #endif // wxUSE_PALETTE
  64     wxArrayString   m_optionNames;
  65     wxArrayString   m_optionValues;
  66 };
  67
  68 wxImageRefData::wxImageRefData()
  69 {
  70     m_width = 0;
  71     m_height = 0;
  72     m_data = (unsigned char*) NULL;
  73     m_ok = FALSE;
  74     m_maskRed = 0;
  75     m_maskGreen = 0;
  76     m_maskBlue = 0;
  77     m_hasMask = FALSE;
  78     m_static = FALSE;
  79 }
  80
  81 wxImageRefData::~wxImageRefData()
  82 {
  83     if (m_data && !m_static)
  84         free( m_data );
  85 }
  86
  87 wxList wxImage::sm_handlers;
  88
  89 wxImage wxNullImage;
  90
  91 //-----------------------------------------------------------------------------
  92
  93 #define M_IMGDATA ((wxImageRefData *)m_refData)
  94
  95 IMPLEMENT_DYNAMIC_CLASS(wxImage, wxObject)
  96
  97 wxImage::wxImage()
  98 {
  99 }
 100
 101 wxImage::wxImage( int width, int height )
 102 {
 103     Create( width, height );
 104 }
 105
 106 wxImage::wxImage( int width, int height, unsigned char* data, bool static_data )
 107 {
 108     Create( width, height, data, static_data );
 109 }
 110
 111 wxImage::wxImage( const wxString& name, long type )
 112 {
 113     LoadFile( name, type );
 114 }
 115
 116 wxImage::wxImage( const wxString& name, const wxString& mimetype )
 117 {
 118     LoadFile( name, mimetype );
 119 }
 120
 121 #if wxUSE_STREAMS
 122 wxImage::wxImage( wxInputStream& stream, long type )
 123 {
 124     LoadFile( stream, type );
 125 }
 126
 127 wxImage::wxImage( wxInputStream& stream, const wxString& mimetype )
 128 {
 129     LoadFile( stream, mimetype );
 130 }
 131 #endif // wxUSE_STREAMS
 132
 133 wxImage::wxImage( const wxImage& image )
 134 {
 135     Ref(image);
 136 }
 137
 138 wxImage::wxImage( const wxImage* image )
 139 {
 140     if (image) Ref(*image);
 141 }
 142
 143 void wxImage::Create( int width, int height )
 144 {
 145     UnRef();
 146
 147     m_refData = new wxImageRefData();
 148
 149     M_IMGDATA->m_data = (unsigned char *) malloc( width*height*3 );
 150     if (M_IMGDATA->m_data)
 151     {
 152         for (int l = 0; l < width*height*3; l++) M_IMGDATA->m_data[l] = 0;
 153
 154         M_IMGDATA->m_width = width;
 155         M_IMGDATA->m_height = height;
 156         M_IMGDATA->m_ok = TRUE;
 157     }
 158     else
 159     {
 160         UnRef();
 161     }
 162 }
 163
 164 void wxImage::Create( int width, int height, unsigned char* data, bool static_data )
 165 {
 166     UnRef();
 167
 168     m_refData = new wxImageRefData();
 169
 170     M_IMGDATA->m_data = data;
 171     if (M_IMGDATA->m_data)
 172     {
 173         M_IMGDATA->m_width = width;
 174         M_IMGDATA->m_height = height;
 175         M_IMGDATA->m_ok = TRUE;
 176         M_IMGDATA->m_static = static_data;
 177     }
 178     else
 179     {
 180         UnRef();
 181     }
 182 }
 183
 184 void wxImage::Destroy()
 185 {
 186     UnRef();
 187 }
 188
 189 wxImage wxImage::Copy() const
 190 {
 191     wxImage image;
 192
 193     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 194
 195     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height );
 196
 197     char unsigned *data = image.GetData();
 198
 199     wxCHECK_MSG( data, image, wxT("unable to create image") );
 200
 201     if (M_IMGDATA->m_hasMask)
 202         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
 203
 204     memcpy( data, GetData(), M_IMGDATA->m_width*M_IMGDATA->m_height*3 );
 205
 206     return image;
 207 }
 208
 209 wxImage wxImage::Scale( int width, int height ) const
 210 {
 211     wxImage image;
 212
 213     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 214
 215     // can't scale to/from 0 size
 216     wxCHECK_MSG( (width > 0) && (height > 0), image,
 217                  wxT("invalid new image size") );
 218
 219     long old_height = M_IMGDATA->m_height,
 220          old_width  = M_IMGDATA->m_width;
 221     wxCHECK_MSG( (old_height > 0) && (old_width > 0), image,
 222                  wxT("invalid old image size") );
 223
 224     image.Create( width, height );
 225
 226     char unsigned *data = image.GetData();
 227
 228     wxCHECK_MSG( data, image, wxT("unable to create image") );
 229
 230     if (M_IMGDATA->m_hasMask)
 231     {
 232         image.SetMaskColour( M_IMGDATA->m_maskRed,
 233                              M_IMGDATA->m_maskGreen,
 234                              M_IMGDATA->m_maskBlue );
 235     }
 236
 237     char unsigned *source_data = M_IMGDATA->m_data;
 238     char unsigned *target_data = data;
 239
 240 #if 0
 241     // This is nonsense, RR.
 242
 243     // We do (x, y) -> (x, y)*oldSize/newSize but the valid values of x and y
 244     // are from 0 to size-1, hence all decrement the sizes
 245     long old_old_width = old_width;
 246     old_height--;
 247     old_width--;
 248     height--;
 249     width--;
 250     for ( long j = 0; j <= height; j++ )
 251     {
 252         // don't crash for images with height == 1
 253         long y_offset = height ? (j * old_height / height)* old_old_width : 0;
 254
 255         for ( long i = 0; i <= width; i++ )
 256         {
 257             long x_offset = width ? (i * old_width) / width : 0;
 258
 259             memcpy( target_data, source_data + 3*(y_offset + x_offset), 3 );
 260             target_data += 3;
 261         }
 262     }
 263 #else
 264     for (long j = 0; j < height; j++)
 265     {
 266         long y_offset = (j * old_height / height) * old_width;
 267
 268         for (long i = 0; i < width; i++)
 269         {
 270             memcpy( target_data,
 271                 source_data + 3*(y_offset + ((i * old_width )/ width)),
 272                 3 );
 273             target_data += 3;
 274         }
 275     }
 276 #endif
 277
 278     return image;
 279 }
 280
 281 wxImage wxImage::Rotate90( bool clockwise ) const
 282 {
 283     wxImage image;
 284
 285     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 286
 287     image.Create( M_IMGDATA->m_height, M_IMGDATA->m_width );
 288
 289     char unsigned *data = image.GetData();
 290
 291     wxCHECK_MSG( data, image, wxT("unable to create image") );
 292
 293     if (M_IMGDATA->m_hasMask)
 294         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
 295
 296     long height = M_IMGDATA->m_height;
 297     long width  = M_IMGDATA->m_width;
 298
 299     char unsigned *source_data = M_IMGDATA->m_data;
 300     char unsigned *target_data;
 301
 302     for (long j = 0; j < height; j++)
 303     {
 304         for (long i = 0; i < width; i++)
 305         {
 306             if (clockwise)
 307                 target_data = data + (((i+1)*height) - j - 1)*3;
 308             else
 309                 target_data = data + ((height*(width-1)) + j - (i*height))*3;
 310             memcpy( target_data, source_data, 3 );
 311             source_data += 3;
 312         }
 313     }
 314
 315     return image;
 316 }
 317
 318 wxImage wxImage::Mirror( bool horizontally ) const
 319 {
 320     wxImage image;
 321
 322     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 323
 324     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height );
 325
 326     char unsigned *data = image.GetData();
 327
 328     wxCHECK_MSG( data, image, wxT("unable to create image") );
 329
 330     if (M_IMGDATA->m_hasMask)
 331         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
 332
 333     long height = M_IMGDATA->m_height;
 334     long width  = M_IMGDATA->m_width;
 335
 336     char unsigned *source_data = M_IMGDATA->m_data;
 337     char unsigned *target_data;
 338
 339     if (horizontally)
 340     {
 341         for (long j = 0; j < height; j++)
 342         {
 343             data += width*3;
 344             target_data = data-3;
 345             for (long i = 0; i < width; i++)
 346             {
 347                 memcpy( target_data, source_data, 3 );
 348                 source_data += 3;
 349                 target_data -= 3;
 350             }
 351         }
 352     }
 353     else
 354     {
 355         for (long i = 0; i < height; i++)
 356         {
 357             target_data = data + 3*width*(height-1-i);
 358             memcpy( target_data, source_data, (size_t)3*width );
 359             source_data += 3*width;
 360         }
 361     }
 362
 363     return image;
 364 }
 365
 366 wxImage wxImage::GetSubImage( const wxRect &rect ) const
 367 {
 368     wxImage image;
 369
 370     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 371
 372     wxCHECK_MSG( (rect.GetLeft()>=0) && (rect.GetTop()>=0) && (rect.GetRight()<=GetWidth()) && (rect.GetBottom()<=GetHeight()),
 373                  image, wxT("invalid subimage size") );
 374
 375     int subwidth=rect.GetWidth();
 376     const int subheight=rect.GetHeight();
 377
 378     image.Create( subwidth, subheight );
 379
 380     char unsigned *subdata = image.GetData(), *data=GetData();
 381
 382     wxCHECK_MSG( subdata, image, wxT("unable to create image") );
 383
 384     if (M_IMGDATA->m_hasMask)
 385         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
 386
 387     const int subleft=3*rect.GetLeft();
 388     const int width=3*GetWidth();
 389     subwidth*=3;
 390
 391     data+=rect.GetTop()*width+subleft;
 392
 393     for (long j = 0; j < subheight; ++j)
 394     {
 395         memcpy( subdata, data, subwidth);
 396         subdata+=subwidth;
 397         data+=width;
 398     }
 399
 400     return image;
 401 }
 402
 403 void wxImage::Paste( const wxImage &image, int x, int y )
 404 {
 405     wxCHECK_RET( Ok(), wxT("invalid image") );
 406     wxCHECK_RET( image.Ok(), wxT("invalid image") );
 407
 408     int xx = 0;
 409     int yy = 0;
 410     int width = image.GetWidth();
 411     int height = image.GetHeight();
 412
 413     if (x < 0)
 414     {
 415         xx = -x;
 416         width += x;
 417     }
 418     if (y < 0)
 419     {
 420         yy = -y;
 421         height += y;
 422     }
 423
 424     if ((x+xx)+width > M_IMGDATA->m_width)
 425         width = M_IMGDATA->m_width - (x+xx);
 426     if ((y+yy)+height > M_IMGDATA->m_height)
 427         height = M_IMGDATA->m_height - (y+yy);
 428
 429     if (width < 1) return;
 430     if (height < 1) return;
 431
 432     if ((!HasMask() && !image.HasMask()) ||
 433        ((HasMask() && image.HasMask() &&
 434          (GetMaskRed()==image.GetMaskRed()) &&
 435          (GetMaskGreen()==image.GetMaskGreen()) &&
 436          (GetMaskBlue()==image.GetMaskBlue()))))
 437     {
 438         width *= 3;
 439         unsigned char* source_data = image.GetData() + xx*3 + yy*3*image.GetWidth();
 440         int source_step = image.GetWidth()*3;
 441
 442         unsigned char* target_data = GetData() + (x+xx)*3 + (y+yy)*3*M_IMGDATA->m_width;
 443         int target_step = M_IMGDATA->m_width*3;
 444         for (int j = 0; j < height; j++)
 445         {
 446             memcpy( target_data, source_data, width );
 447             source_data += source_step;
 448             target_data += target_step;
 449         }
 450         return;
 451     }
 452
 453     if (!HasMask() && image.HasMask())
 454     {
 455         unsigned char r = image.GetMaskRed();
 456         unsigned char g = image.GetMaskGreen();
 457         unsigned char b = image.GetMaskBlue();
 458
 459         width *= 3;
 460         unsigned char* source_data = image.GetData() + xx*3 + yy*3*image.GetWidth();
 461         int source_step = image.GetWidth()*3;
 462
 463         unsigned char* target_data = GetData() + (x+xx)*3 + (y+yy)*3*M_IMGDATA->m_width;
 464         int target_step = M_IMGDATA->m_width*3;
 465
 466         for (int j = 0; j < height; j++)
 467         {
 468             for (int i = 0; i < width; i+=3)
 469             {
 470                 if ((source_data[i]   != r) &&
 471                     (source_data[i+1] != g) &&
 472                     (source_data[i+2] != b))
 473                 {
 474                     memcpy( target_data+i, source_data+i, 3 );
 475                 }
 476             }
 477             source_data += source_step;
 478             target_data += target_step;
 479         }
 480     }
 481 }
 482
 483 void wxImage::Replace( unsigned char r1, unsigned char g1, unsigned char b1,
 484                        unsigned char r2, unsigned char g2, unsigned char b2 )
 485 {
 486     wxCHECK_RET( Ok(), wxT("invalid image") );
 487
 488     char unsigned *data = GetData();
 489
 490     const int w = GetWidth();
 491     const int h = GetHeight();
 492
 493     for (int j = 0; j < h; j++)
 494         for (int i = 0; i < w; i++)
 495         {
 496             if ((data[0] == r1) && (data[1] == g1) && (data[2] == b1))
 497             {
 498                 data[0] = r2;
 499                 data[1] = g2;
 500                 data[2] = b2;
 501             }
 502             data += 3;
 503         }
 504 }
 505
 506 wxImage wxImage::ConvertToMono( unsigned char r, unsigned char g, unsigned char b ) const
 507 {
 508     wxImage image;
 509
 510     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 511
 512     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height );
 513
 514     char unsigned *data = image.GetData();
 515
 516     wxCHECK_MSG( data, image, wxT("unable to create image") );
 517
 518     if (M_IMGDATA->m_hasMask)
 519     {
 520         if (M_IMGDATA->m_maskRed == r && M_IMGDATA->m_maskGreen == g &&
 521                                          M_IMGDATA->m_maskBlue == b)
 522             image.SetMaskColour( 255, 255, 255 );
 523         else
 524             image.SetMaskColour( 0, 0, 0 );
 525     }
 526
 527     long size = M_IMGDATA->m_height * M_IMGDATA->m_width;
 528
 529     char unsigned *srcd = M_IMGDATA->m_data;
 530     char unsigned *tard = image.GetData();
 531
 532     for ( long i = 0; i < size; i++, srcd += 3, tard += 3 )
 533     {
 534         if (srcd[0] == r && srcd[1] == g && srcd[2] == b)
 535             tard[0] = tard[1] = tard[2] = 255;
 536         else
 537             tard[0] = tard[1] = tard[2] = 0;
 538     }
 539
 540     return image;
 541 }
 542
 543 void wxImage::SetRGB( int x, int y, unsigned char r, unsigned char g, unsigned char b )
 544 {
 545     wxCHECK_RET( Ok(), wxT("invalid image") );
 546
 547     int w = M_IMGDATA->m_width;
 548     int h = M_IMGDATA->m_height;
 549
 550     wxCHECK_RET( (x>=0) && (y>=0) && (x<w) && (y<h), wxT("invalid image index") );
 551
 552     long pos = (y * w + x) * 3;
 553
 554     M_IMGDATA->m_data[ pos   ] = r;
 555     M_IMGDATA->m_data[ pos+1 ] = g;
 556     M_IMGDATA->m_data[ pos+2 ] = b;
 557 }
 558
 559 unsigned char wxImage::GetRed( int x, int y ) const
 560 {
 561     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 562
 563     int w = M_IMGDATA->m_width;
 564     int h = M_IMGDATA->m_height;
 565
 566     wxCHECK_MSG( (x>=0) && (y>=0) && (x<w) && (y<h), 0, wxT("invalid image index") );
 567
 568     long pos = (y * w + x) * 3;
 569
 570     return M_IMGDATA->m_data[pos];
 571 }
 572
 573 unsigned char wxImage::GetGreen( int x, int y ) const
 574 {
 575     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 576
 577     int w = M_IMGDATA->m_width;
 578     int h = M_IMGDATA->m_height;
 579
 580     wxCHECK_MSG( (x>=0) && (y>=0) && (x<w) && (y<h), 0, wxT("invalid image index") );
 581
 582     long pos = (y * w + x) * 3;
 583
 584     return M_IMGDATA->m_data[pos+1];
 585 }
 586
 587 unsigned char wxImage::GetBlue( int x, int y ) const
 588 {
 589     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 590
 591     int w = M_IMGDATA->m_width;
 592     int h = M_IMGDATA->m_height;
 593
 594     wxCHECK_MSG( (x>=0) && (y>=0) && (x<w) && (y<h), 0, wxT("invalid image index") );
 595
 596     long pos = (y * w + x) * 3;
 597
 598     return M_IMGDATA->m_data[pos+2];
 599 }
 600
 601 bool wxImage::Ok() const
 602 {
 603     // image of 0 width or height can't be considered ok - at least because it
 604     // causes crashes in ConvertToBitmap() if we don't catch it in time
 605     wxImageRefData *data = M_IMGDATA;
 606     return data && data->m_ok && data->m_width && data->m_height;
 607 }
 608
 609 char unsigned *wxImage::GetData() const
 610 {
 611     wxCHECK_MSG( Ok(), (char unsigned *)NULL, wxT("invalid image") );
 612
 613     return M_IMGDATA->m_data;
 614 }
 615
 616 void wxImage::SetData( char unsigned *data )
 617 {
 618     wxCHECK_RET( Ok(), wxT("invalid image") );
 619
 620     wxImageRefData *newRefData = new wxImageRefData();
 621
 622     newRefData->m_width = M_IMGDATA->m_width;
 623     newRefData->m_height = M_IMGDATA->m_height;
 624     newRefData->m_data = data;
 625     newRefData->m_ok = TRUE;
 626     newRefData->m_maskRed = M_IMGDATA->m_maskRed;
 627     newRefData->m_maskGreen = M_IMGDATA->m_maskGreen;
 628     newRefData->m_maskBlue = M_IMGDATA->m_maskBlue;
 629     newRefData->m_hasMask = M_IMGDATA->m_hasMask;
 630
 631     UnRef();
 632
 633     m_refData = newRefData;
 634 }
 635
 636 void wxImage::SetData( char unsigned *data, int new_width, int new_height )
 637 {
 638     wxImageRefData *newRefData = new wxImageRefData();
 639
 640     if (m_refData)
 641     {
 642         newRefData->m_width = new_width;
 643         newRefData->m_height = new_height;
 644         newRefData->m_data = data;
 645         newRefData->m_ok = TRUE;
 646         newRefData->m_maskRed = M_IMGDATA->m_maskRed;
 647         newRefData->m_maskGreen = M_IMGDATA->m_maskGreen;
 648         newRefData->m_maskBlue = M_IMGDATA->m_maskBlue;
 649         newRefData->m_hasMask = M_IMGDATA->m_hasMask;
 650     }
 651     else
 652     {
 653         newRefData->m_width = new_width;
 654         newRefData->m_height = new_height;
 655         newRefData->m_data = data;
 656         newRefData->m_ok = TRUE;
 657     }
 658
 659     UnRef();
 660
 661     m_refData = newRefData;
 662 }
 663
 664 void wxImage::SetMaskColour( unsigned char r, unsigned char g, unsigned char b )
 665 {
 666     wxCHECK_RET( Ok(), wxT("invalid image") );
 667
 668     M_IMGDATA->m_maskRed = r;
 669     M_IMGDATA->m_maskGreen = g;
 670     M_IMGDATA->m_maskBlue = b;
 671     M_IMGDATA->m_hasMask = TRUE;
 672 }
 673
 674 unsigned char wxImage::GetMaskRed() const
 675 {
 676     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 677
 678     return M_IMGDATA->m_maskRed;
 679 }
 680
 681 unsigned char wxImage::GetMaskGreen() const
 682 {
 683     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 684
 685     return M_IMGDATA->m_maskGreen;
 686 }
 687
 688 unsigned char wxImage::GetMaskBlue() const
 689 {
 690     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 691
 692     return M_IMGDATA->m_maskBlue;
 693 }
 694
 695 void wxImage::SetMask( bool mask )
 696 {
 697     wxCHECK_RET( Ok(), wxT("invalid image") );
 698
 699     M_IMGDATA->m_hasMask = mask;
 700 }
 701
 702 bool wxImage::HasMask() const
 703 {
 704     wxCHECK_MSG( Ok(), FALSE, wxT("invalid image") );
 705
 706     return M_IMGDATA->m_hasMask;
 707 }
 708
 709 int wxImage::GetWidth() const
 710 {
 711     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 712
 713     return M_IMGDATA->m_width;
 714 }
 715
 716 int wxImage::GetHeight() const
 717 {
 718     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 719
 720     return M_IMGDATA->m_height;
 721 }
 722
 723
 724 bool wxImage::GetUnusedColour (  unsigned char * r,  unsigned char * g,  unsigned char * b )
 725 {
 726     wxHashTable hTable;
 727     unsigned long key;
 728
 729     ComputeHistogram( hTable );
 730
 731     // start with blackest color and work to lightest
 732     // 0,0,0 is quite likely to be a used color
 733     unsigned char r2 = 1;
 734     unsigned char g2 = 0;
 735     unsigned char b2 = 0;
 736
 737     key = (r2 << 16) | (g2 << 8) | b2;
 738
 739     while ( (wxHNode *) hTable.Get(key) )
 740     {
 741         // color already used
 742         r2 ++ ;
 743         if ( r2 >= 255 )
 744         {
 745             r2 = 0;
 746             g2 ++ ;
 747             if ( g2 >= 255 )
 748             {
 749                 g2 = 0 ;
 750                 b2 ++ ;
 751                 if ( b2 >= 255 )
 752                 {
 753                     wxLogError( _("GetUnusedColour:: No Unused Color in image ") );
 754                     return FALSE;
 755                 }
 756             }
 757         }
 758
 759         key = (r2 << 16) | (g2 << 8) | b2;
 760     }
 761
 762     return TRUE;
 763 }
 764
 765
 766 bool wxImage::ApplyMask ( const wxImage & mask )
 767 {
 768     // what to do if we already have a mask ??
 769     if (M_IMGDATA->m_hasMask || mask.HasMask() )
 770     {
 771         wxLogError( _("Image already masked") );
 772         return FALSE;
 773     }
 774
 775     // check that the images are the same size
 776     if ( (M_IMGDATA->m_height != mask.GetHeight() ) || (M_IMGDATA->m_width != mask.GetWidth () ) )
 777     {
 778         wxLogError( _("Image and Mask have different sizes") );
 779         return FALSE;
 780     }
 781
 782     // find unused colour
 783     unsigned char r,g,b ;
 784     if (!GetUnusedColour (&r, &g, &b))
 785     {
 786         wxLogError( _("No Unused Color in image being masked") );
 787         return FALSE ;
 788     }
 789
 790     char unsigned *imgdata = GetData();
 791     char unsigned *maskdata = mask.GetData();
 792
 793     const int w = GetWidth();
 794     const int h = GetHeight();
 795
 796     for (int j = 0; j < h; j++)
 797         for (int i = 0; i < w; i++)
 798         {
 799             if ((maskdata[0] > 128) && (maskdata[1] > 128) && (maskdata[2] > 128 ))
 800             {
 801                 imgdata[0] = r;
 802                 imgdata[1] = g;
 803                 imgdata[2] = b;
 804             }
 805             imgdata  += 3;
 806             maskdata += 3;
 807         }
 808
 809     M_IMGDATA->m_maskRed = r;
 810     M_IMGDATA->m_maskGreen = g;
 811     M_IMGDATA->m_maskBlue = b;
 812     M_IMGDATA->m_hasMask = TRUE;
 813
 814     return TRUE;
 815 }
 816
 817 #if wxUSE_PALETTE
 818
 819 // Palette functions
 820
 821 bool wxImage::HasPalette() const
 822 {
 823     if (!Ok())
 824         return FALSE;
 825
 826     return M_IMGDATA->m_palette.Ok();
 827 }
 828
 829 const wxPalette& wxImage::GetPalette() const
 830 {
 831     wxCHECK_MSG( Ok(), wxNullPalette, wxT("invalid image") );
 832
 833     return M_IMGDATA->m_palette;
 834 }
 835
 836 void wxImage::SetPalette(const wxPalette& palette)
 837 {
 838     wxCHECK_RET( Ok(), wxT("invalid image") );
 839
 840     M_IMGDATA->m_palette = palette;
 841 }
 842
 843 #endif // wxUSE_PALETTE
 844
 845 // Option functions (arbitrary name/value mapping)
 846 void wxImage::SetOption(const wxString& name, const wxString& value)
 847 {
 848     wxCHECK_RET( Ok(), wxT("invalid image") );
 849
 850     int idx = M_IMGDATA->m_optionNames.Index(name, FALSE);
 851     if (idx == wxNOT_FOUND)
 852     {
 853         M_IMGDATA->m_optionNames.Add(name);
 854         M_IMGDATA->m_optionValues.Add(value);
 855     }
 856     else
 857     {
 858         M_IMGDATA->m_optionNames[idx] = name;
 859         M_IMGDATA->m_optionValues[idx] = value;
 860     }
 861 }
 862
 863 void wxImage::SetOption(const wxString& name, int value)
 864 {
 865     wxString valStr;
 866     valStr.Printf(wxT("%d"), value);
 867     SetOption(name, valStr);
 868 }
 869
 870 wxString wxImage::GetOption(const wxString& name) const
 871 {
 872     wxCHECK_MSG( Ok(), wxEmptyString, wxT("invalid image") );
 873
 874     int idx = M_IMGDATA->m_optionNames.Index(name, FALSE);
 875     if (idx == wxNOT_FOUND)
 876         return wxEmptyString;
 877     else
 878         return M_IMGDATA->m_optionValues[idx];
 879 }
 880
 881 int wxImage::GetOptionInt(const wxString& name) const
 882 {
 883     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
 884
 885     return wxAtoi(GetOption(name));
 886 }
 887
 888 bool wxImage::HasOption(const wxString& name) const
 889 {
 890     wxCHECK_MSG( Ok(), FALSE, wxT("invalid image") );
 891
 892     return (M_IMGDATA->m_optionNames.Index(name, FALSE) != wxNOT_FOUND);
 893 }
 894
 895 bool wxImage::LoadFile( const wxString& filename, long type )
 896 {
 897 #if wxUSE_STREAMS
 898     if (wxFileExists(filename))
 899     {
 900         wxFileInputStream stream(filename);
 901         wxBufferedInputStream bstream( stream );
 902         return LoadFile(bstream, type);
 903     }
 904     else
 905     {
 906         wxLogError( _("Can't load image from file '%s': file does not exist."), filename.c_str() );
 907
 908         return FALSE;
 909     }
 910 #else // !wxUSE_STREAMS
 911     return FALSE;
 912 #endif // wxUSE_STREAMS
 913 }
 914
 915 bool wxImage::LoadFile( const wxString& filename, const wxString& mimetype )
 916 {
 917 #if wxUSE_STREAMS
 918     if (wxFileExists(filename))
 919     {
 920         wxFileInputStream stream(filename);
 921         wxBufferedInputStream bstream( stream );
 922         return LoadFile(bstream, mimetype);
 923     }
 924     else
 925     {
 926         wxLogError( _("Can't load image from file '%s': file does not exist."), filename.c_str() );
 927
 928         return FALSE;
 929     }
 930 #else // !wxUSE_STREAMS
 931     return FALSE;
 932 #endif // wxUSE_STREAMS
 933 }
 934
 935 bool wxImage::SaveFile( const wxString& filename, int type )
 936 {
 937 #if wxUSE_STREAMS
 938     wxFileOutputStream stream(filename);
 939
 940     if ( stream.LastError() == wxStream_NOERROR )
 941     {
 942         wxBufferedOutputStream bstream( stream );
 943         return SaveFile(bstream, type);
 944     }
 945 #endif // wxUSE_STREAMS
 946
 947     return FALSE;
 948 }
 949
 950 bool wxImage::SaveFile( const wxString& filename, const wxString& mimetype )
 951 {
 952 #if wxUSE_STREAMS
 953     wxFileOutputStream stream(filename);
 954
 955     if ( stream.LastError() == wxStream_NOERROR )
 956     {
 957         wxBufferedOutputStream bstream( stream );
 958         return SaveFile(bstream, mimetype);
 959     }
 960 #endif // wxUSE_STREAMS
 961
 962     return FALSE;
 963 }
 964
 965 bool wxImage::CanRead( const wxString &name )
 966 {
 967 #if wxUSE_STREAMS
 968   wxFileInputStream stream(name);
 969   return CanRead(stream);
 970 #else
 971   return FALSE;
 972 #endif
 973 }
 974
 975 #if wxUSE_STREAMS
 976
 977 bool wxImage::CanRead( wxInputStream &stream )
 978 {
 979   wxList &list=GetHandlers();
 980
 981   for ( wxList::Node *node = list.GetFirst(); node; node = node->GetNext() )
 982     {
 983       wxImageHandler *handler=(wxImageHandler*)node->GetData();
 984       if (handler->CanRead( stream ))
 985         return TRUE;
 986     }
 987
 988   return FALSE;
 989 }
 990
 991 bool wxImage::LoadFile( wxInputStream& stream, long type )
 992 {
 993     UnRef();
 994
 995     m_refData = new wxImageRefData;
 996
 997     wxImageHandler *handler;
 998
 999     if (type==wxBITMAP_TYPE_ANY)
1000     {
1001         wxList &list=GetHandlers();
1002
1003         for ( wxList::Node *node = list.GetFirst(); node; node = node->GetNext() )
1004         {
1005              handler=(wxImageHandler*)node->GetData();
1006              if (handler->CanRead( stream ))
1007                  return handler->LoadFile( this, stream );
1008
1009         }
1010
1011         wxLogWarning( _("No handler found for image type.") );
1012         return FALSE;
1013     }
1014
1015     handler = FindHandler(type);
1016
1017     if (handler == NULL)
1018     {
1019         wxLogWarning( _("No image handler for type %d defined."), type );
1020
1021         return FALSE;
1022     }
1023
1024     return handler->LoadFile( this, stream );
1025 }
1026
1027 bool wxImage::LoadFile( wxInputStream& stream, const wxString& mimetype )
1028 {
1029     UnRef();
1030
1031     m_refData = new wxImageRefData;
1032
1033     wxImageHandler *handler = FindHandlerMime(mimetype);
1034
1035     if (handler == NULL)
1036     {
1037         wxLogWarning( _("No image handler for type %s defined."), mimetype.GetData() );
1038
1039         return FALSE;
1040     }
1041
1042     return handler->LoadFile( this, stream );
1043 }
1044
1045 bool wxImage::SaveFile( wxOutputStream& stream, int type )
1046 {
1047     wxCHECK_MSG( Ok(), FALSE, wxT("invalid image") );
1048
1049     wxImageHandler *handler = FindHandler(type);
1050
1051     if (handler == NULL)
1052     {
1053         wxLogWarning( _("No image handler for type %d defined."), type );
1054
1055         return FALSE;
1056     }
1057
1058     return handler->SaveFile( this, stream );
1059 }
1060
1061 bool wxImage::SaveFile( wxOutputStream& stream, const wxString& mimetype )
1062 {
1063     wxCHECK_MSG( Ok(), FALSE, wxT("invalid image") );
1064
1065     wxImageHandler *handler = FindHandlerMime(mimetype);
1066
1067     if (handler == NULL)
1068     {
1069         wxLogWarning( _("No image handler for type %s defined."), mimetype.GetData() );
1070
1071         return FALSE;
1072     }
1073
1074     return handler->SaveFile( this, stream );
1075 }
1076 #endif // wxUSE_STREAMS
1077
1078 void wxImage::AddHandler( wxImageHandler *handler )
1079 {
1080     // make sure that the memory will be freed at the program end
1081     sm_handlers.DeleteContents(TRUE);
1082
1083     sm_handlers.Append( handler );
1084 }
1085
1086 void wxImage::InsertHandler( wxImageHandler *handler )
1087 {
1088     // make sure that the memory will be freed at the program end
1089     sm_handlers.DeleteContents(TRUE);
1090
1091     sm_handlers.Insert( handler );
1092 }
1093
1094 bool wxImage::RemoveHandler( const wxString& name )
1095 {
1096     wxImageHandler *handler = FindHandler(name);
1097     if (handler)
1098     {
1099         sm_handlers.DeleteObject(handler);
1100         return TRUE;
1101     }
1102     else
1103         return FALSE;
1104 }
1105
1106 wxImageHandler *wxImage::FindHandler( const wxString& name )
1107 {
1108     wxNode *node = sm_handlers.First();
1109     while (node)
1110     {
1111         wxImageHandler *handler = (wxImageHandler*)node->Data();
1112         if (handler->GetName().Cmp(name) == 0) return handler;
1113
1114         node = node->Next();
1115     }
1116     return (wxImageHandler *)NULL;
1117 }
1118
1119 wxImageHandler *wxImage::FindHandler( const wxString& extension, long bitmapType )
1120 {
1121     wxNode *node = sm_handlers.First();
1122     while (node)
1123     {
1124         wxImageHandler *handler = (wxImageHandler*)node->Data();
1125         if ( (handler->GetExtension().Cmp(extension) == 0) &&
1126             (bitmapType == -1 || handler->GetType() == bitmapType) )
1127             return handler;
1128         node = node->Next();
1129     }
1130     return (wxImageHandler*)NULL;
1131 }
1132
1133 wxImageHandler *wxImage::FindHandler( long bitmapType )
1134 {
1135     wxNode *node = sm_handlers.First();
1136     while (node)
1137     {
1138         wxImageHandler *handler = (wxImageHandler *)node->Data();
1139         if (handler->GetType() == bitmapType) return handler;
1140         node = node->Next();
1141     }
1142     return NULL;
1143 }
1144
1145 wxImageHandler *wxImage::FindHandlerMime( const wxString& mimetype )
1146 {
1147     wxNode *node = sm_handlers.First();
1148     while (node)
1149     {
1150         wxImageHandler *handler = (wxImageHandler *)node->Data();
1151         if (handler->GetMimeType().IsSameAs(mimetype, FALSE)) return handler;
1152         node = node->Next();
1153     }
1154     return NULL;
1155 }
1156
1157 void wxImage::InitStandardHandlers()
1158 {
1159     AddHandler(new wxBMPHandler);
1160 #if wxUSE_XPM && !defined(__WXGTK__) && !defined(__WXMOTIF__)
1161     AddHandler(new wxXPMHandler);
1162 #endif
1163 }
1164
1165 void wxImage::CleanUpHandlers()
1166 {
1167     wxNode *node = sm_handlers.First();
1168     while (node)
1169     {
1170         wxImageHandler *handler = (wxImageHandler *)node->Data();
1171         wxNode *next = node->Next();
1172         delete handler;
1173         delete node;
1174         node = next;
1175     }
1176 }
1177
1178 //-----------------------------------------------------------------------------
1179 // wxImageHandler
1180 //-----------------------------------------------------------------------------
1181
1182 IMPLEMENT_ABSTRACT_CLASS(wxImageHandler,wxObject)
1183
1184 #if wxUSE_STREAMS
1185 bool wxImageHandler::LoadFile( wxImage *WXUNUSED(image), wxInputStream& WXUNUSED(stream), bool WXUNUSED(verbose), int WXUNUSED(index) )
1186 {
1187     return FALSE;
1188 }
1189
1190 bool wxImageHandler::SaveFile( wxImage *WXUNUSED(image), wxOutputStream& WXUNUSED(stream), bool WXUNUSED(verbose) )
1191 {
1192     return FALSE;
1193 }
1194
1195 int wxImageHandler::GetImageCount( wxInputStream& WXUNUSED(stream) )
1196 {
1197     return 1;
1198 }
1199
1200 bool wxImageHandler::CanRead( const wxString& name )
1201 {
1202     if (wxFileExists(name))
1203     {
1204         wxFileInputStream stream(name);
1205         return CanRead(stream);
1206     }
1207
1208     else {
1209         wxLogError( _("Can't check image format of file '%s': file does not exist."), name.c_str() );
1210
1211         return FALSE;
1212     }
1213 //    return FALSE;
1214 }
1215
1216 #endif // wxUSE_STREAMS
1217
1218
1219
1220 //-----------------------------------------------------------------------------
1221 // wxBitmap convertion routines
1222 //-----------------------------------------------------------------------------
1223
1224 #if wxUSE_GUI
1225
1226 #ifdef __WXGTK__
1227 wxBitmap wxImage::ConvertToMonoBitmap( unsigned char red, unsigned char green, unsigned char blue ) const
1228 {
1229     wxImage mono = this->ConvertToMono( red, green, blue );
1230     wxBitmap bitmap( mono, 1 );
1231     return bitmap;
1232 }
1233 #endif
1234
1235 wxBitmap wxImage::ConvertToBitmap() const
1236 {
1237     wxBitmap bitmap( *this );
1238     return bitmap;
1239 }
1240
1241 wxImage::wxImage( const wxBitmap &bitmap )
1242 {
1243     *this = bitmap.ConvertToImage();
1244 }
1245
1246 #endif
1247
1248
1249
1250 // A module to allow wxImage initialization/cleanup
1251 // without calling these functions from app.cpp or from
1252 // the user's application.
1253
1254 class wxImageModule: public wxModule
1255 {
1256 DECLARE_DYNAMIC_CLASS(wxImageModule)
1257 public:
1258     wxImageModule() {}
1259     bool OnInit() { wxImage::InitStandardHandlers(); return TRUE; };
1260     void OnExit() { wxImage::CleanUpHandlers(); };
1261 };
1262
1263 IMPLEMENT_DYNAMIC_CLASS(wxImageModule, wxModule)
1264
1265
1266 //-----------------------------------------------------------------------------
1267
1268 // GRG, Dic/99
1269 // Counts and returns the number of different colours. Optionally stops
1270 // when it exceeds 'stopafter' different colours. This is useful, for
1271 // example, to see if the image can be saved as 8-bit (256 colour or
1272 // less, in this case it would be invoked as CountColours(256)). Default
1273 // value for stopafter is -1 (don't care).
1274 //
1275 unsigned long wxImage::CountColours( unsigned long stopafter )
1276 {
1277     wxHashTable h;
1278     wxObject dummy;
1279     unsigned char r, g, b;
1280     unsigned char *p;
1281     unsigned long size, nentries, key;
1282
1283     p = GetData();
1284     size = GetWidth() * GetHeight();
1285     nentries = 0;
1286
1287     for (unsigned long j = 0; (j < size) && (nentries <= stopafter) ; j++)
1288     {
1289         r = *(p++);
1290         g = *(p++);
1291         b = *(p++);
1292         key = (r << 16) | (g << 8) | b;
1293
1294         if (h.Get(key) == NULL)
1295         {
1296             h.Put(key, &dummy);
1297             nentries++;
1298         }
1299     }
1300
1301     return nentries;
1302 }
1303
1304
1305 // GRG, Dic/99
1306 // Computes the histogram of the image and fills a hash table, indexed
1307 // with integer keys built as 0xRRGGBB, containing wxHNode objects. Each
1308 // wxHNode contains an 'index' (useful to build a palette with the image
1309 // colours) and a 'value', which is the number of pixels in the image with
1310 // that colour.
1311 //
1312 unsigned long wxImage::ComputeHistogram( wxHashTable &h )
1313 {
1314     unsigned char r, g, b;
1315     unsigned char *p;
1316     unsigned long size, nentries, key;
1317     wxHNode *hnode;
1318
1319     p = GetData();
1320     size = GetWidth() * GetHeight();
1321     nentries = 0;
1322
1323     for (unsigned long j = 0; j < size; j++)
1324     {
1325         r = *(p++);
1326         g = *(p++);
1327         b = *(p++);
1328         key = (r << 16) | (g << 8) | b;
1329
1330         hnode = (wxHNode *) h.Get(key);
1331
1332         if (hnode)
1333             hnode->value++;
1334         else
1335         {
1336             hnode = new wxHNode();
1337             hnode->index = nentries++;
1338             hnode->value = 1;
1339
1340             h.Put(key, (wxObject *)hnode);
1341         }
1342     }
1343
1344     return nentries;
1345 }
1346
1347 /*
1348  * Rotation code by Carlos Moreno
1349  */
1350
1351 // GRG: I've removed wxRotationPoint - we already have wxRealPoint which
1352 //      does exactly the same thing. And I also got rid of wxRotationPixel
1353 //      bacause of potential problems in architectures where alignment
1354 //      is an issue, so I had to rewrite parts of the code.
1355
1356 static const double gs_Epsilon = 1e-10;
1357
1358 static inline int wxCint (double x)
1359 {
1360     return (x > 0) ? (int) (x + 0.5) : (int) (x - 0.5);
1361 }
1362
1363
1364 // Auxiliary function to rotate a point (x,y) with respect to point p0
1365 // make it inline and use a straight return to facilitate optimization
1366 // also, the function receives the sine and cosine of the angle to avoid
1367 // repeating the time-consuming calls to these functions -- sin/cos can
1368 // be computed and stored in the calling function.
1369
1370 inline wxRealPoint rotated_point (const wxRealPoint & p, double cos_angle, double sin_angle, const wxRealPoint & p0)
1371 {
1372     return wxRealPoint (p0.x + (p.x - p0.x) * cos_angle - (p.y - p0.y) * sin_angle,
1373                         p0.y + (p.y - p0.y) * cos_angle + (p.x - p0.x) * sin_angle);
1374 }
1375
1376 inline wxRealPoint rotated_point (double x, double y, double cos_angle, double sin_angle, const wxRealPoint & p0)
1377 {
1378     return rotated_point (wxRealPoint(x,y), cos_angle, sin_angle, p0);
1379 }
1380
1381 wxImage wxImage::Rotate(double angle, const wxPoint & centre_of_rotation, bool interpolating, wxPoint * offset_after_rotation) const
1382 {
1383     int i;
1384     angle = -angle;     // screen coordinates are a mirror image of "real" coordinates
1385
1386     // Create pointer-based array to accelerate access to wxImage's data
1387     unsigned char ** data = new unsigned char * [GetHeight()];
1388
1389     data[0] = GetData();
1390
1391     for (i = 1; i < GetHeight(); i++)
1392         data[i] = data[i - 1] + (3 * GetWidth());
1393
1394     // precompute coefficients for rotation formula
1395     // (sine and cosine of the angle)
1396     const double cos_angle = cos(angle);
1397     const double sin_angle = sin(angle);
1398
1399     // Create new Image to store the result
1400     // First, find rectangle that covers the rotated image;  to do that,
1401     // rotate the four corners
1402
1403     const wxRealPoint p0(centre_of_rotation.x, centre_of_rotation.y);
1404
1405     wxRealPoint p1 = rotated_point (0, 0, cos_angle, sin_angle, p0);
1406     wxRealPoint p2 = rotated_point (0, GetHeight(), cos_angle, sin_angle, p0);
1407     wxRealPoint p3 = rotated_point (GetWidth(), 0, cos_angle, sin_angle, p0);
1408     wxRealPoint p4 = rotated_point (GetWidth(), GetHeight(), cos_angle, sin_angle, p0);
1409
1410     int x1 = (int) floor (wxMin (wxMin(p1.x, p2.x), wxMin(p3.x, p4.x)));
1411     int y1 = (int) floor (wxMin (wxMin(p1.y, p2.y), wxMin(p3.y, p4.y)));
1412     int x2 = (int) ceil (wxMax (wxMax(p1.x, p2.x), wxMax(p3.x, p4.x)));
1413     int y2 = (int) ceil (wxMax (wxMax(p1.y, p2.y), wxMax(p3.y, p4.y)));
1414
1415     wxImage rotated (x2 - x1 + 1, y2 - y1 + 1);
1416
1417     if (offset_after_rotation != NULL)
1418     {
1419         *offset_after_rotation = wxPoint (x1, y1);
1420     }
1421
1422     // GRG: The rotated (destination) image is always accessed
1423     //      sequentially, so there is no need for a pointer-based
1424     //      array here (and in fact it would be slower).
1425     //
1426     unsigned char * dst = rotated.GetData();
1427
1428     // GRG: if the original image has a mask, use its RGB values
1429     //      as the blank pixel, else, fall back to default (black).
1430     //
1431     unsigned char blank_r = 0;
1432     unsigned char blank_g = 0;
1433     unsigned char blank_b = 0;
1434
1435     if (HasMask())
1436     {
1437         blank_r = GetMaskRed();
1438         blank_g = GetMaskGreen();
1439         blank_b = GetMaskBlue();
1440         rotated.SetMaskColour( blank_r, blank_g, blank_b );
1441     }
1442
1443     // Now, for each point of the rotated image, find where it came from, by
1444     // performing an inverse rotation (a rotation of -angle) and getting the
1445     // pixel at those coordinates
1446
1447     // GRG: I've taken the (interpolating) test out of the loops, so that
1448     //      it is done only once, instead of repeating it for each pixel.
1449
1450     int x;
1451     if (interpolating)
1452     {
1453         for (int y = 0; y < rotated.GetHeight(); y++)
1454         {
1455             for (x = 0; x < rotated.GetWidth(); x++)
1456             {
1457                 wxRealPoint src = rotated_point (x + x1, y + y1, cos_angle, -sin_angle, p0);
1458
1459                 if (-0.25 < src.x && src.x < GetWidth() - 0.75 &&
1460                     -0.25 < src.y && src.y < GetHeight() - 0.75)
1461                 {
1462                     // interpolate using the 4 enclosing grid-points.  Those
1463                     // points can be obtained using floor and ceiling of the
1464                     // exact coordinates of the point
1465                         // C.M. 2000-02-17:  when the point is near the border, special care is required.
1466
1467                     int x1, y1, x2, y2;
1468
1469                     if (0 < src.x && src.x < GetWidth() - 1)
1470                     {
1471                         x1 = wxCint(floor(src.x));
1472                         x2 = wxCint(ceil(src.x));
1473                     }
1474                     else    // else means that x is near one of the borders (0 or width-1)
1475                     {
1476                         x1 = x2 = wxCint (src.x);
1477                     }
1478
1479                     if (0 < src.y && src.y < GetHeight() - 1)
1480                     {
1481                         y1 = wxCint(floor(src.y));
1482                         y2 = wxCint(ceil(src.y));
1483                     }
1484                     else
1485                     {
1486                         y1 = y2 = wxCint (src.y);
1487                     }
1488
1489                     // get four points and the distances (square of the distance,
1490                     // for efficiency reasons) for the interpolation formula
1491
1492                     // GRG: Do not calculate the points until they are
1493                     //      really needed -- this way we can calculate
1494                     //      just one, instead of four, if d1, d2, d3
1495                     //      or d4 are < gs_Epsilon
1496
1497                     const double d1 = (src.x - x1) * (src.x - x1) + (src.y - y1) * (src.y - y1);
1498                     const double d2 = (src.x - x2) * (src.x - x2) + (src.y - y1) * (src.y - y1);
1499                     const double d3 = (src.x - x2) * (src.x - x2) + (src.y - y2) * (src.y - y2);
1500                     const double d4 = (src.x - x1) * (src.x - x1) + (src.y - y2) * (src.y - y2);
1501
1502                     // Now interpolate as a weighted average of the four surrounding
1503                     // points, where the weights are the distances to each of those points
1504
1505                     // If the point is exactly at one point of the grid of the source
1506                     // image, then don't interpolate -- just assign the pixel
1507
1508                     if (d1 < gs_Epsilon)        // d1,d2,d3,d4 are positive -- no need for abs()
1509                     {
1510                         unsigned char *p = data[y1] + (3 * x1);
1511                         *(dst++) = *(p++);
1512                         *(dst++) = *(p++);
1513                         *(dst++) = *(p++);
1514                     }
1515                     else if (d2 < gs_Epsilon)
1516                     {
1517                         unsigned char *p = data[y1] + (3 * x2);
1518                         *(dst++) = *(p++);
1519                         *(dst++) = *(p++);
1520                         *(dst++) = *(p++);
1521                     }
1522                     else if (d3 < gs_Epsilon)
1523                     {
1524                         unsigned char *p = data[y2] + (3 * x2);
1525                         *(dst++) = *(p++);
1526                         *(dst++) = *(p++);
1527                         *(dst++) = *(p++);
1528                     }
1529                     else if (d4 < gs_Epsilon)
1530                     {
1531                         unsigned char *p = data[y2] + (3 * x1);
1532                         *(dst++) = *(p++);
1533                         *(dst++) = *(p++);
1534                         *(dst++) = *(p++);
1535                     }
1536                     else
1537                     {
1538                         // weights for the weighted average are proportional to the inverse of the distance
1539                         unsigned char *v1 = data[y1] + (3 * x1);
1540                         unsigned char *v2 = data[y1] + (3 * x2);
1541                         unsigned char *v3 = data[y2] + (3 * x2);
1542                         unsigned char *v4 = data[y2] + (3 * x1);
1543
1544                         const double w1 = 1/d1, w2 = 1/d2, w3 = 1/d3, w4 = 1/d4;
1545
1546                         // GRG: Unrolled.
1547
1548                         *(dst++) = (unsigned char)
1549                             ( (w1 * *(v1++) + w2 * *(v2++) +
1550                                w3 * *(v3++) + w4 * *(v4++)) /
1551                               (w1 + w2 + w3 + w4) );
1552                         *(dst++) = (unsigned char)
1553                             ( (w1 * *(v1++) + w2 * *(v2++) +
1554                                w3 * *(v3++) + w4 * *(v4++)) /
1555                               (w1 + w2 + w3 + w4) );
1556                         *(dst++) = (unsigned char)
1557                             ( (w1 * *(v1++) + w2 * *(v2++) +
1558                                w3 * *(v3++) + w4 * *(v4++)) /
1559                               (w1 + w2 + w3 + w4) );
1560                     }
1561                 }
1562                 else
1563                 {
1564                     *(dst++) = blank_r;
1565                     *(dst++) = blank_g;
1566                     *(dst++) = blank_b;
1567                 }
1568             }
1569         }
1570     }
1571     else    // not interpolating
1572     {
1573         for (int y = 0; y < rotated.GetHeight(); y++)
1574         {
1575             for (x = 0; x < rotated.GetWidth(); x++)
1576             {
1577                 wxRealPoint src = rotated_point (x + x1, y + y1, cos_angle, -sin_angle, p0);
1578
1579                 const int xs = wxCint (src.x);      // wxCint rounds to the
1580                 const int ys = wxCint (src.y);      // closest integer
1581
1582                 if (0 <= xs && xs < GetWidth() &&
1583                     0 <= ys && ys < GetHeight())
1584                 {
1585                     unsigned char *p = data[ys] + (3 * xs);
1586                     *(dst++) = *(p++);
1587                     *(dst++) = *(p++);
1588                     *(dst++) = *(p++);
1589                 }
1590                 else
1591                 {
1592                     *(dst++) = blank_r;
1593                     *(dst++) = blank_g;
1594                     *(dst++) = blank_b;
1595                 }
1596             }
1597         }
1598     }
1599
1600     delete [] data;
1601
1602     return rotated;
1603 }
1604
1605 #endif // wxUSE_IMAGE