src/common/image.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/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 // For compilers that support precompilation, includes "wx.h".
  11 #include "wx/wxprec.h"
  12
  13 #ifdef __BORLANDC__
  14     #pragma hdrstop
  15 #endif
  16
  17 #if wxUSE_IMAGE
  18
  19 #include "wx/image.h"
  20
  21 #ifndef WX_PRECOMP
  22     #include "wx/log.h"
  23     #include "wx/hash.h"
  24     #include "wx/utils.h"
  25     #include "wx/math.h"
  26     #include "wx/module.h"
  27     #include "wx/palette.h"
  28     #include "wx/intl.h"
  29 #endif
  30
  31 #include "wx/filefn.h"
  32 #include "wx/wfstream.h"
  33 #include "wx/xpmdecod.h"
  34
  35 // For memcpy
  36 #include <string.h>
  37
  38 // make the code compile with either wxFile*Stream or wxFFile*Stream:
  39 #define HAS_FILE_STREAMS (wxUSE_STREAMS && (wxUSE_FILE || wxUSE_FFILE))
  40
  41 #if HAS_FILE_STREAMS
  42     #if wxUSE_FILE
  43         typedef wxFileInputStream wxImageFileInputStream;
  44         typedef wxFileOutputStream wxImageFileOutputStream;
  45     #elif wxUSE_FFILE
  46         typedef wxFFileInputStream wxImageFileInputStream;
  47         typedef wxFFileOutputStream wxImageFileOutputStream;
  48     #endif // wxUSE_FILE/wxUSE_FFILE
  49 #endif // HAS_FILE_STREAMS
  50
  51 #if wxUSE_VARIANT
  52 IMPLEMENT_VARIANT_OBJECT_EXPORTED_SHALLOWCMP(wxImage,WXDLLEXPORT)
  53 #endif
  54
  55 //-----------------------------------------------------------------------------
  56 // wxImage
  57 //-----------------------------------------------------------------------------
  58
  59 class wxImageRefData: public wxObjectRefData
  60 {
  61 public:
  62     wxImageRefData();
  63     virtual ~wxImageRefData();
  64
  65     int             m_width;
  66     int             m_height;
  67     unsigned char  *m_data;
  68
  69     bool            m_hasMask;
  70     unsigned char   m_maskRed,m_maskGreen,m_maskBlue;
  71
  72     // alpha channel data, may be NULL for the formats without alpha support
  73     unsigned char  *m_alpha;
  74
  75     bool            m_ok;
  76
  77     // if true, m_data is pointer to static data and shouldn't be freed
  78     bool            m_static;
  79
  80     // same as m_static but for m_alpha
  81     bool            m_staticAlpha;
  82
  83 #if wxUSE_PALETTE
  84     wxPalette       m_palette;
  85 #endif // wxUSE_PALETTE
  86
  87     wxArrayString   m_optionNames;
  88     wxArrayString   m_optionValues;
  89
  90     DECLARE_NO_COPY_CLASS(wxImageRefData)
  91 };
  92
  93 wxImageRefData::wxImageRefData()
  94 {
  95     m_width = 0;
  96     m_height = 0;
  97     m_data =
  98     m_alpha = (unsigned char *) NULL;
  99
 100     m_maskRed = 0;
 101     m_maskGreen = 0;
 102     m_maskBlue = 0;
 103     m_hasMask = false;
 104
 105     m_ok = false;
 106     m_static =
 107     m_staticAlpha = false;
 108 }
 109
 110 wxImageRefData::~wxImageRefData()
 111 {
 112     if ( !m_static )
 113         free( m_data );
 114     if ( !m_staticAlpha )
 115         free( m_alpha );
 116 }
 117
 118 wxList wxImage::sm_handlers;
 119
 120 wxImage wxNullImage;
 121
 122 //-----------------------------------------------------------------------------
 123
 124 #define M_IMGDATA wx_static_cast(wxImageRefData*, m_refData)
 125
 126 IMPLEMENT_DYNAMIC_CLASS(wxImage, wxObject)
 127
 128 wxImage::wxImage( int width, int height, bool clear )
 129 {
 130     Create( width, height, clear );
 131 }
 132
 133 wxImage::wxImage( int width, int height, unsigned char* data, bool static_data )
 134 {
 135     Create( width, height, data, static_data );
 136 }
 137
 138 wxImage::wxImage( int width, int height, unsigned char* data, unsigned char* alpha, bool static_data )
 139 {
 140     Create( width, height, data, alpha, static_data );
 141 }
 142
 143 wxImage::wxImage( const wxString& name, long type, int index )
 144 {
 145     LoadFile( name, type, index );
 146 }
 147
 148 wxImage::wxImage( const wxString& name, const wxString& mimetype, int index )
 149 {
 150     LoadFile( name, mimetype, index );
 151 }
 152
 153 #if wxUSE_STREAMS
 154 wxImage::wxImage( wxInputStream& stream, long type, int index )
 155 {
 156     LoadFile( stream, type, index );
 157 }
 158
 159 wxImage::wxImage( wxInputStream& stream, const wxString& mimetype, int index )
 160 {
 161     LoadFile( stream, mimetype, index );
 162 }
 163 #endif // wxUSE_STREAMS
 164
 165 wxImage::wxImage(const char* const* xpmData)
 166 {
 167     Create(xpmData);
 168 }
 169
 170 bool wxImage::Create(const char* const* xpmData)
 171 {
 172 #if wxUSE_XPM
 173     UnRef();
 174
 175     wxXPMDecoder decoder;
 176     (*this) = decoder.ReadData(xpmData);
 177     return Ok();
 178 #else
 179     return false;
 180 #endif
 181 }
 182
 183 bool wxImage::Create( int width, int height, bool clear )
 184 {
 185     UnRef();
 186
 187     m_refData = new wxImageRefData();
 188
 189     M_IMGDATA->m_data = (unsigned char *) malloc( width*height*3 );
 190     if (!M_IMGDATA->m_data)
 191     {
 192         UnRef();
 193         return false;
 194     }
 195
 196     if (clear)
 197         memset(M_IMGDATA->m_data, 0, width*height*3);
 198
 199     M_IMGDATA->m_width = width;
 200     M_IMGDATA->m_height = height;
 201     M_IMGDATA->m_ok = true;
 202
 203     return true;
 204 }
 205
 206 bool wxImage::Create( int width, int height, unsigned char* data, bool static_data )
 207 {
 208     UnRef();
 209
 210     wxCHECK_MSG( data, false, _T("NULL data in wxImage::Create") );
 211
 212     m_refData = new wxImageRefData();
 213
 214     M_IMGDATA->m_data = data;
 215     M_IMGDATA->m_width = width;
 216     M_IMGDATA->m_height = height;
 217     M_IMGDATA->m_ok = true;
 218     M_IMGDATA->m_static = static_data;
 219
 220     return true;
 221 }
 222
 223 bool wxImage::Create( int width, int height, unsigned char* data, unsigned char* alpha, bool static_data )
 224 {
 225     UnRef();
 226
 227     wxCHECK_MSG( data, false, _T("NULL data in wxImage::Create") );
 228
 229     m_refData = new wxImageRefData();
 230
 231     M_IMGDATA->m_data = data;
 232     M_IMGDATA->m_alpha = alpha;
 233     M_IMGDATA->m_width = width;
 234     M_IMGDATA->m_height = height;
 235     M_IMGDATA->m_ok = true;
 236     M_IMGDATA->m_static = static_data;
 237
 238     return true;
 239 }
 240
 241 void wxImage::Destroy()
 242 {
 243     UnRef();
 244 }
 245
 246 wxObjectRefData* wxImage::CreateRefData() const
 247 {
 248     return new wxImageRefData;
 249 }
 250
 251 wxObjectRefData* wxImage::CloneRefData(const wxObjectRefData* that) const
 252 {
 253     const wxImageRefData* refData = wx_static_cast(const wxImageRefData*, that);
 254     wxCHECK_MSG(refData->m_ok, NULL, wxT("invalid image") );
 255
 256     wxImageRefData* refData_new = new wxImageRefData;
 257     refData_new->m_width = refData->m_width;
 258     refData_new->m_height = refData->m_height;
 259     refData_new->m_maskRed = refData->m_maskRed;
 260     refData_new->m_maskGreen = refData->m_maskGreen;
 261     refData_new->m_maskBlue = refData->m_maskBlue;
 262     refData_new->m_hasMask = refData->m_hasMask;
 263     refData_new->m_ok = true;
 264     unsigned size = unsigned(refData->m_width) * unsigned(refData->m_height);
 265     if (refData->m_alpha != NULL)
 266     {
 267         refData_new->m_alpha = (unsigned char*)malloc(size);
 268         memcpy(refData_new->m_alpha, refData->m_alpha, size);
 269     }
 270     size *= 3;
 271     refData_new->m_data = (unsigned char*)malloc(size);
 272     memcpy(refData_new->m_data, refData->m_data, size);
 273 #if wxUSE_PALETTE
 274     refData_new->m_palette = refData->m_palette;
 275 #endif
 276     refData_new->m_optionNames = refData->m_optionNames;
 277     refData_new->m_optionValues = refData->m_optionValues;
 278     return refData_new;
 279 }
 280
 281 wxImage wxImage::Copy() const
 282 {
 283     wxImage image;
 284
 285     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 286
 287     image.m_refData = CloneRefData(m_refData);
 288
 289     return image;
 290 }
 291
 292 wxImage wxImage::ShrinkBy( int xFactor , int yFactor ) const
 293 {
 294     if( xFactor == 1 && yFactor == 1 )
 295         return *this;
 296
 297     wxImage image;
 298
 299     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 300
 301     // can't scale to/from 0 size
 302     wxCHECK_MSG( (xFactor > 0) && (yFactor > 0), image,
 303                  wxT("invalid new image size") );
 304
 305     long old_height = M_IMGDATA->m_height,
 306          old_width  = M_IMGDATA->m_width;
 307
 308     wxCHECK_MSG( (old_height > 0) && (old_width > 0), image,
 309                  wxT("invalid old image size") );
 310
 311     long width = old_width / xFactor ;
 312     long height = old_height / yFactor ;
 313
 314     image.Create( width, height, false );
 315
 316     char unsigned *data = image.GetData();
 317
 318     wxCHECK_MSG( data, image, wxT("unable to create image") );
 319
 320     bool hasMask = false ;
 321     unsigned char maskRed = 0;
 322     unsigned char maskGreen = 0;
 323     unsigned char maskBlue =0 ;
 324
 325     unsigned char *source_data = M_IMGDATA->m_data;
 326     unsigned char *target_data = data;
 327     unsigned char *source_alpha = 0 ;
 328     unsigned char *target_alpha = 0 ;
 329     if (M_IMGDATA->m_hasMask)
 330     {
 331         hasMask = true ;
 332         maskRed = M_IMGDATA->m_maskRed;
 333         maskGreen = M_IMGDATA->m_maskGreen;
 334         maskBlue =M_IMGDATA->m_maskBlue ;
 335
 336         image.SetMaskColour( M_IMGDATA->m_maskRed,
 337                              M_IMGDATA->m_maskGreen,
 338                              M_IMGDATA->m_maskBlue );
 339     }
 340     else
 341     {
 342         source_alpha = M_IMGDATA->m_alpha ;
 343         if ( source_alpha )
 344         {
 345             image.SetAlpha() ;
 346             target_alpha = image.GetAlpha() ;
 347         }
 348     }
 349
 350     for (long y = 0; y < height; y++)
 351     {
 352         for (long x = 0; x < width; x++)
 353         {
 354             unsigned long avgRed = 0 ;
 355             unsigned long avgGreen = 0;
 356             unsigned long avgBlue = 0;
 357             unsigned long avgAlpha = 0 ;
 358             unsigned long counter = 0 ;
 359             // determine average
 360             for ( int y1 = 0 ; y1 < yFactor ; ++y1 )
 361             {
 362                 long y_offset = (y * yFactor + y1) * old_width;
 363                 for ( int x1 = 0 ; x1 < xFactor ; ++x1 )
 364                 {
 365                     unsigned char *pixel = source_data + 3 * ( y_offset + x * xFactor + x1 ) ;
 366                     unsigned char red = pixel[0] ;
 367                     unsigned char green = pixel[1] ;
 368                     unsigned char blue = pixel[2] ;
 369                     unsigned char alpha = 255  ;
 370                     if ( source_alpha )
 371                         alpha = *(source_alpha + y_offset + x * xFactor + x1) ;
 372                     if ( !hasMask || red != maskRed || green != maskGreen || blue != maskBlue )
 373                     {
 374                         if ( alpha > 0 )
 375                         {
 376                             avgRed += red ;
 377                             avgGreen += green ;
 378                             avgBlue += blue ;
 379                         }
 380                         avgAlpha += alpha ;
 381                         counter++ ;
 382                     }
 383                 }
 384             }
 385             if ( counter == 0 )
 386             {
 387                 *(target_data++) = M_IMGDATA->m_maskRed ;
 388                 *(target_data++) = M_IMGDATA->m_maskGreen ;
 389                 *(target_data++) = M_IMGDATA->m_maskBlue ;
 390             }
 391             else
 392             {
 393                 if ( source_alpha )
 394                     *(target_alpha++) = (unsigned char)(avgAlpha / counter ) ;
 395                 *(target_data++) = (unsigned char)(avgRed / counter);
 396                 *(target_data++) = (unsigned char)(avgGreen / counter);
 397                 *(target_data++) = (unsigned char)(avgBlue / counter);
 398             }
 399         }
 400     }
 401
 402     // In case this is a cursor, make sure the hotspot is scaled accordingly:
 403     if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X) )
 404         image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X,
 405                 (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X))/xFactor);
 406     if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y) )
 407         image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y,
 408                 (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y))/yFactor);
 409
 410     return image;
 411 }
 412
 413 wxImage wxImage::Scale( int width, int height, int quality ) const
 414 {
 415     wxImage image;
 416
 417     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 418
 419     // can't scale to/from 0 size
 420     wxCHECK_MSG( (width > 0) && (height > 0), image,
 421                  wxT("invalid new image size") );
 422
 423     long old_height = M_IMGDATA->m_height,
 424          old_width  = M_IMGDATA->m_width;
 425     wxCHECK_MSG( (old_height > 0) && (old_width > 0), image,
 426                  wxT("invalid old image size") );
 427
 428     // If the image's new width and height are the same as the original, no
 429     // need to waste time or CPU cycles
 430     if ( old_width == width && old_height == height )
 431         return *this;
 432
 433     // Scale the image (...or more appropriately, resample the image) using
 434     // either the high-quality or normal method as specified
 435     if ( quality == wxIMAGE_QUALITY_HIGH )
 436     {
 437         // We need to check whether we are downsampling or upsampling the image
 438         if ( width < old_width && height < old_height )
 439         {
 440             // Downsample the image using the box averaging method for best results
 441             image = ResampleBox(width, height);
 442         }
 443         else
 444         {
 445             // For upsampling or other random/wierd image dimensions we'll use
 446             // a bicubic b-spline scaling method
 447             image = ResampleBicubic(width, height);
 448         }
 449     }
 450     else    // Default scaling method == simple pixel replication
 451     {
 452         if ( old_width % width == 0 && old_width >= width &&
 453             old_height % height == 0 && old_height >= height )
 454         {
 455             return ShrinkBy( old_width / width , old_height / height ) ;
 456         }
 457         image.Create( width, height, false );
 458
 459         unsigned char *data = image.GetData();
 460
 461         wxCHECK_MSG( data, image, wxT("unable to create image") );
 462
 463         unsigned char *source_data = M_IMGDATA->m_data;
 464         unsigned char *target_data = data;
 465         unsigned char *source_alpha = 0 ;
 466         unsigned char *target_alpha = 0 ;
 467
 468         if ( !M_IMGDATA->m_hasMask )
 469         {
 470             source_alpha = M_IMGDATA->m_alpha ;
 471             if ( source_alpha )
 472             {
 473                 image.SetAlpha() ;
 474                 target_alpha = image.GetAlpha() ;
 475             }
 476         }
 477
 478         long x_delta = (old_width<<16) / width;
 479         long y_delta = (old_height<<16) / height;
 480
 481         unsigned char* dest_pixel = target_data;
 482
 483         long y = 0;
 484         for ( long j = 0; j < height; j++ )
 485         {
 486             unsigned char* src_line = &source_data[(y>>16)*old_width*3];
 487             unsigned char* src_alpha_line = source_alpha ? &source_alpha[(y>>16)*old_width] : 0 ;
 488
 489             long x = 0;
 490             for ( long i = 0; i < width; i++ )
 491             {
 492                 unsigned char* src_pixel = &src_line[(x>>16)*3];
 493                 unsigned char* src_alpha_pixel = source_alpha ? &src_alpha_line[(x>>16)] : 0 ;
 494                 dest_pixel[0] = src_pixel[0];
 495                 dest_pixel[1] = src_pixel[1];
 496                 dest_pixel[2] = src_pixel[2];
 497                 dest_pixel += 3;
 498                 if ( source_alpha )
 499                     *(target_alpha++) = *src_alpha_pixel ;
 500                 x += x_delta;
 501             }
 502
 503             y += y_delta;
 504         }
 505     }
 506
 507     // If the original image has a mask, apply the mask to the new image
 508     if (M_IMGDATA->m_hasMask)
 509     {
 510         image.SetMaskColour( M_IMGDATA->m_maskRed,
 511                             M_IMGDATA->m_maskGreen,
 512                             M_IMGDATA->m_maskBlue );
 513     }
 514
 515     // In case this is a cursor, make sure the hotspot is scaled accordingly:
 516     if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X) )
 517         image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X,
 518                 (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X)*width)/old_width);
 519     if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y) )
 520         image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y,
 521                 (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y)*height)/old_height);
 522
 523     return image;
 524 }
 525
 526 wxImage wxImage::ResampleBox(int width, int height) const
 527 {
 528     // This function implements a simple pre-blur/box averaging method for
 529     // downsampling that gives reasonably smooth results To scale the image
 530     // down we will need to gather a grid of pixels of the size of the scale
 531     // factor in each direction and then do an averaging of the pixels.
 532
 533     wxImage ret_image(width, height, false);
 534
 535     const double scale_factor_x = double(M_IMGDATA->m_width) / width;
 536     const double scale_factor_y = double(M_IMGDATA->m_height) / height;
 537
 538     const int scale_factor_x_2 = (int)(scale_factor_x / 2);
 539     const int scale_factor_y_2 = (int)(scale_factor_y / 2);
 540
 541     // If we want good-looking results we need to pre-blur the image a bit first
 542     wxImage src_image(*this);
 543     src_image = src_image.BlurHorizontal(scale_factor_x_2);
 544     src_image = src_image.BlurVertical(scale_factor_y_2);
 545
 546     unsigned char* src_data = src_image.GetData();
 547     unsigned char* src_alpha = src_image.GetAlpha();
 548     unsigned char* dst_data = ret_image.GetData();
 549     unsigned char* dst_alpha = NULL;
 550
 551     if ( src_alpha )
 552     {
 553         ret_image.SetAlpha();
 554         dst_alpha = ret_image.GetAlpha();
 555     }
 556
 557     int averaged_pixels, src_pixel_index;
 558     double sum_r, sum_g, sum_b, sum_a;
 559
 560     for ( int y = 0; y < height; y++ )         // Destination image - Y direction
 561     {
 562         // Source pixel in the Y direction
 563         int src_y = (int)(y * scale_factor_y);
 564
 565         for ( int x = 0; x < width; x++ )      // Destination image - X direction
 566         {
 567             // Source pixel in the X direction
 568             int src_x = (int)(x * scale_factor_x);
 569
 570             // Box of pixels to average
 571             averaged_pixels = 0;
 572             sum_r = sum_g = sum_b = sum_a = 0.0;
 573
 574             for ( int j = int(src_y - scale_factor_y/2.0 + 1);
 575                   j <= int(src_y + scale_factor_y_2);
 576                   j++ )
 577             {
 578                 // We don't care to average pixels that don't exist (edges)
 579                 if ( j < 0 || j > M_IMGDATA->m_height )
 580                     continue;
 581
 582                 for ( int i = int(src_x - scale_factor_x/2.0 + 1);
 583                       i <= src_x + scale_factor_x_2;
 584                       i++ )
 585                 {
 586                     // Don't average edge pixels
 587                     if ( i < 0 || i > M_IMGDATA->m_width )
 588                         continue;
 589
 590                     // Calculate the actual index in our source pixels
 591                     src_pixel_index = src_y * M_IMGDATA->m_width + src_x;
 592
 593                     sum_r += src_data[src_pixel_index * 3 + 0];
 594                     sum_g += src_data[src_pixel_index * 3 + 1];
 595                     sum_b += src_data[src_pixel_index * 3 + 2];
 596                     if ( src_alpha )
 597                         sum_a += src_alpha[src_pixel_index];
 598
 599                     averaged_pixels++;
 600                 }
 601             }
 602
 603             // Calculate the average from the sum and number of averaged pixels
 604             dst_data[0] = (unsigned char)(sum_r / averaged_pixels);
 605             dst_data[1] = (unsigned char)(sum_g / averaged_pixels);
 606             dst_data[2] = (unsigned char)(sum_b / averaged_pixels);
 607             dst_data += 3;
 608             if ( src_alpha )
 609                 *dst_alpha++ = (unsigned char)(sum_a / averaged_pixels);
 610         }
 611     }
 612
 613     return ret_image;
 614 }
 615
 616 // The following two local functions are for the B-spline weighting of the
 617 // bicubic sampling algorithm
 618 static inline double spline_cube(double value)
 619 {
 620     return value <= 0.0 ? 0.0 : value * value * value;
 621 }
 622
 623 static inline double spline_weight(double value)
 624 {
 625     return (spline_cube(value + 2) -
 626             4 * spline_cube(value + 1) +
 627             6 * spline_cube(value) -
 628             4 * spline_cube(value - 1)) / 6;
 629 }
 630
 631 // This is the bicubic resampling algorithm
 632 wxImage wxImage::ResampleBicubic(int width, int height) const
 633 {
 634     // This function implements a Bicubic B-Spline algorithm for resampling.
 635     // This method is certainly a little slower than wxImage's default pixel
 636     // replication method, however for most reasonably sized images not being
 637     // upsampled too much on a fairly average CPU this difference is hardly
 638     // noticeable and the results are far more pleasing to look at.
 639     //
 640     // This particular bicubic algorithm does pixel weighting according to a
 641     // B-Spline that basically implements a Gaussian bell-like weighting
 642     // kernel. Because of this method the results may appear a bit blurry when
 643     // upsampling by large factors.  This is basically because a slight
 644     // gaussian blur is being performed to get the smooth look of the upsampled
 645     // image.
 646
 647     // Edge pixels: 3-4 possible solutions
 648     // - (Wrap/tile) Wrap the image, take the color value from the opposite
 649     // side of the image.
 650     // - (Mirror)    Duplicate edge pixels, so that pixel at coordinate (2, n),
 651     // where n is nonpositive, will have the value of (2, 1).
 652     // - (Ignore)    Simply ignore the edge pixels and apply the kernel only to
 653     // pixels which do have all neighbours.
 654     // - (Clamp)     Choose the nearest pixel along the border. This takes the
 655     // border pixels and extends them out to infinity.
 656     //
 657     // NOTE: below the y_offset and x_offset variables are being set for edge
 658     // pixels using the "Mirror" method mentioned above
 659
 660     wxImage ret_image;
 661
 662     ret_image.Create(width, height, false);
 663
 664     unsigned char* src_data = M_IMGDATA->m_data;
 665     unsigned char* src_alpha = M_IMGDATA->m_alpha;
 666     unsigned char* dst_data = ret_image.GetData();
 667     unsigned char* dst_alpha = NULL;
 668
 669     if ( src_alpha )
 670     {
 671         ret_image.SetAlpha();
 672         dst_alpha = ret_image.GetAlpha();
 673     }
 674
 675     for ( int dsty = 0; dsty < height; dsty++ )
 676     {
 677         // We need to calculate the source pixel to interpolate from - Y-axis
 678         double srcpixy = dsty * M_IMGDATA->m_height / height;
 679         double dy = srcpixy - (int)srcpixy;
 680
 681         for ( int dstx = 0; dstx < width; dstx++ )
 682         {
 683             // X-axis of pixel to interpolate from
 684             double srcpixx = dstx * M_IMGDATA->m_width / width;
 685             double dx = srcpixx - (int)srcpixx;
 686
 687             // Sums for each color channel
 688             double sum_r = 0, sum_g = 0, sum_b = 0, sum_a = 0;
 689
 690             // Here we actually determine the RGBA values for the destination pixel
 691             for ( int k = -1; k <= 2; k++ )
 692             {
 693                 // Y offset
 694                 int y_offset = srcpixy + k < 0.0
 695                                 ? 0
 696                                 : srcpixy + k >= M_IMGDATA->m_height
 697                                        ? M_IMGDATA->m_height - 1
 698                                        : (int)(srcpixy + k);
 699
 700                 // Loop across the X axis
 701                 for ( int i = -1; i <= 2; i++ )
 702                 {
 703                     // X offset
 704                     int x_offset = srcpixx + i < 0.0
 705                                     ? 0
 706                                     : srcpixx + i >= M_IMGDATA->m_width
 707                                             ? M_IMGDATA->m_width - 1
 708                                             : (int)(srcpixx + i);
 709
 710                     // Calculate the exact position where the source data
 711                     // should be pulled from based on the x_offset and y_offset
 712                     int src_pixel_index = y_offset*M_IMGDATA->m_width + x_offset;
 713
 714                     // Calculate the weight for the specified pixel according
 715                     // to the bicubic b-spline kernel we're using for
 716                     // interpolation
 717                     double
 718                         pixel_weight = spline_weight(i - dx)*spline_weight(k - dy);
 719
 720                     // Create a sum of all velues for each color channel
 721                     // adjusted for the pixel's calculated weight
 722                     sum_r += src_data[src_pixel_index * 3 + 0] * pixel_weight;
 723                     sum_g += src_data[src_pixel_index * 3 + 1] * pixel_weight;
 724                     sum_b += src_data[src_pixel_index * 3 + 2] * pixel_weight;
 725                     if ( src_alpha )
 726                         sum_a += src_alpha[src_pixel_index] * pixel_weight;
 727                 }
 728             }
 729
 730             // Put the data into the destination image.  The summed values are
 731             // of double data type and are rounded here for accuracy
 732             dst_data[0] = (unsigned char)(sum_r + 0.5);
 733             dst_data[1] = (unsigned char)(sum_g + 0.5);
 734             dst_data[2] = (unsigned char)(sum_b + 0.5);
 735             dst_data += 3;
 736
 737             if ( src_alpha )
 738                 *dst_alpha++ = (unsigned char)sum_a;
 739         }
 740     }
 741
 742     return ret_image;
 743 }
 744
 745 // Blur in the horizontal direction
 746 wxImage wxImage::BlurHorizontal(int blurRadius)
 747 {
 748     wxImage ret_image;
 749     ret_image.Create(M_IMGDATA->m_width, M_IMGDATA->m_height, false);
 750
 751     unsigned char* src_data = M_IMGDATA->m_data;
 752     unsigned char* dst_data = ret_image.GetData();
 753     unsigned char* src_alpha = M_IMGDATA->m_alpha;
 754     unsigned char* dst_alpha = NULL;
 755
 756     // Check for a mask or alpha
 757     if ( M_IMGDATA->m_hasMask )
 758     {
 759         ret_image.SetMaskColour(M_IMGDATA->m_maskRed,
 760                                 M_IMGDATA->m_maskGreen,
 761                                 M_IMGDATA->m_maskBlue);
 762     }
 763     else
 764     {
 765         if ( src_alpha )
 766         {
 767             ret_image.SetAlpha();
 768             dst_alpha = ret_image.GetAlpha();
 769         }
 770     }
 771
 772     // number of pixels we average over
 773     const int blurArea = blurRadius*2 + 1;
 774
 775     // Horizontal blurring algorithm - average all pixels in the specified blur
 776     // radius in the X or horizontal direction
 777     for ( int y = 0; y < M_IMGDATA->m_height; y++ )
 778     {
 779         // Variables used in the blurring algorithm
 780         long sum_r = 0,
 781              sum_g = 0,
 782              sum_b = 0,
 783              sum_a = 0;
 784
 785         long pixel_idx;
 786         const unsigned char *src;
 787         unsigned char *dst;
 788
 789         // Calculate the average of all pixels in the blur radius for the first
 790         // pixel of the row
 791         for ( int kernel_x = -blurRadius; kernel_x <= blurRadius; kernel_x++ )
 792         {
 793             // To deal with the pixels at the start of a row so it's not
 794             // grabbing GOK values from memory at negative indices of the
 795             // image's data or grabbing from the previous row
 796             if ( kernel_x < 0 )
 797                 pixel_idx = y * M_IMGDATA->m_width;
 798             else
 799                 pixel_idx = kernel_x + y * M_IMGDATA->m_width;
 800
 801             src = src_data + pixel_idx*3;
 802             sum_r += src[0];
 803             sum_g += src[1];
 804             sum_b += src[2];
 805             if ( src_alpha )
 806                 sum_a += src_alpha[pixel_idx];
 807         }
 808
 809         dst = dst_data + y * M_IMGDATA->m_width*3;
 810         dst[0] = (unsigned char)(sum_r / blurArea);
 811         dst[1] = (unsigned char)(sum_g / blurArea);
 812         dst[2] = (unsigned char)(sum_b / blurArea);
 813         if ( src_alpha )
 814             dst_alpha[y * M_IMGDATA->m_width] = (unsigned char)(sum_a / blurArea);
 815
 816         // Now average the values of the rest of the pixels by just moving the
 817         // blur radius box along the row
 818         for ( int x = 1; x < M_IMGDATA->m_width; x++ )
 819         {
 820             // Take care of edge pixels on the left edge by essentially
 821             // duplicating the edge pixel
 822             if ( x - blurRadius - 1 < 0 )
 823                 pixel_idx = y * M_IMGDATA->m_width;
 824             else
 825                 pixel_idx = (x - blurRadius - 1) + y * M_IMGDATA->m_width;
 826
 827             // Subtract the value of the pixel at the left side of the blur
 828             // radius box
 829             src = src_data + pixel_idx*3;
 830             sum_r -= src[0];
 831             sum_g -= src[1];
 832             sum_b -= src[2];
 833             if ( src_alpha )
 834                 sum_a -= src_alpha[pixel_idx];
 835
 836             // Take care of edge pixels on the right edge
 837             if ( x + blurRadius > M_IMGDATA->m_width - 1 )
 838                 pixel_idx = M_IMGDATA->m_width - 1 + y * M_IMGDATA->m_width;
 839             else
 840                 pixel_idx = x + blurRadius + y * M_IMGDATA->m_width;
 841
 842             // Add the value of the pixel being added to the end of our box
 843             src = src_data + pixel_idx*3;
 844             sum_r += src[0];
 845             sum_g += src[1];
 846             sum_b += src[2];
 847             if ( src_alpha )
 848                 sum_a += src_alpha[pixel_idx];
 849
 850             // Save off the averaged data
 851             dst = dst_data + x*3 + y*M_IMGDATA->m_width*3;
 852             dst[0] = (unsigned char)(sum_r / blurArea);
 853             dst[1] = (unsigned char)(sum_g / blurArea);
 854             dst[2] = (unsigned char)(sum_b / blurArea);
 855             if ( src_alpha )
 856                 dst_alpha[x + y * M_IMGDATA->m_width] = (unsigned char)(sum_a / blurArea);
 857         }
 858     }
 859
 860     return ret_image;
 861 }
 862
 863 // Blur in the vertical direction
 864 wxImage wxImage::BlurVertical(int blurRadius)
 865 {
 866     wxImage ret_image;
 867     ret_image.Create(M_IMGDATA->m_width, M_IMGDATA->m_height, false);
 868
 869     unsigned char* src_data = M_IMGDATA->m_data;
 870     unsigned char* dst_data = ret_image.GetData();
 871     unsigned char* src_alpha = M_IMGDATA->m_alpha;
 872     unsigned char* dst_alpha = NULL;
 873
 874     // Check for a mask or alpha
 875     if ( M_IMGDATA->m_hasMask )
 876     {
 877         ret_image.SetMaskColour(M_IMGDATA->m_maskRed,
 878                                 M_IMGDATA->m_maskGreen,
 879                                 M_IMGDATA->m_maskBlue);
 880     }
 881     else
 882     {
 883         if ( src_alpha )
 884         {
 885             ret_image.SetAlpha();
 886             dst_alpha = ret_image.GetAlpha();
 887         }
 888     }
 889
 890     // number of pixels we average over
 891     const int blurArea = blurRadius*2 + 1;
 892
 893     // Vertical blurring algorithm - same as horizontal but switched the
 894     // opposite direction
 895     for ( int x = 0; x < M_IMGDATA->m_width; x++ )
 896     {
 897         // Variables used in the blurring algorithm
 898         long sum_r = 0,
 899              sum_g = 0,
 900              sum_b = 0,
 901              sum_a = 0;
 902
 903         long pixel_idx;
 904         const unsigned char *src;
 905         unsigned char *dst;
 906
 907         // Calculate the average of all pixels in our blur radius box for the
 908         // first pixel of the column
 909         for ( int kernel_y = -blurRadius; kernel_y <= blurRadius; kernel_y++ )
 910         {
 911             // To deal with the pixels at the start of a column so it's not
 912             // grabbing GOK values from memory at negative indices of the
 913             // image's data or grabbing from the previous column
 914             if ( kernel_y < 0 )
 915                 pixel_idx = x;
 916             else
 917                 pixel_idx = x + kernel_y * M_IMGDATA->m_width;
 918
 919             src = src_data + pixel_idx*3;
 920             sum_r += src[0];
 921             sum_g += src[1];
 922             sum_b += src[2];
 923             if ( src_alpha )
 924                 sum_a += src_alpha[pixel_idx];
 925         }
 926
 927         dst = dst_data + x*3;
 928         dst[0] = (unsigned char)(sum_r / blurArea);
 929         dst[1] = (unsigned char)(sum_g / blurArea);
 930         dst[2] = (unsigned char)(sum_b / blurArea);
 931         if ( src_alpha )
 932             dst_alpha[x] = (unsigned char)(sum_a / blurArea);
 933
 934         // Now average the values of the rest of the pixels by just moving the
 935         // box along the column from top to bottom
 936         for ( int y = 1; y < M_IMGDATA->m_height; y++ )
 937         {
 938             // Take care of pixels that would be beyond the top edge by
 939             // duplicating the top edge pixel for the column
 940             if ( y - blurRadius - 1 < 0 )
 941                 pixel_idx = x;
 942             else
 943                 pixel_idx = x + (y - blurRadius - 1) * M_IMGDATA->m_width;
 944
 945             // Subtract the value of the pixel at the top of our blur radius box
 946             src = src_data + pixel_idx*3;
 947             sum_r -= src[0];
 948             sum_g -= src[1];
 949             sum_b -= src[2];
 950             if ( src_alpha )
 951                 sum_a -= src_alpha[pixel_idx];
 952
 953             // Take care of the pixels that would be beyond the bottom edge of
 954             // the image similar to the top edge
 955             if ( y + blurRadius > M_IMGDATA->m_height - 1 )
 956                 pixel_idx = x + (M_IMGDATA->m_height - 1) * M_IMGDATA->m_width;
 957             else
 958                 pixel_idx = x + (blurRadius + y) * M_IMGDATA->m_width;
 959
 960             // Add the value of the pixel being added to the end of our box
 961             src = src_data + pixel_idx*3;
 962             sum_r += src[0];
 963             sum_g += src[1];
 964             sum_b += src[2];
 965             if ( src_alpha )
 966                 sum_a += src_alpha[pixel_idx];
 967
 968             // Save off the averaged data
 969             dst = dst_data + (x + y * M_IMGDATA->m_width) * 3;
 970             dst[0] = (unsigned char)(sum_r / blurArea);
 971             dst[1] = (unsigned char)(sum_g / blurArea);
 972             dst[2] = (unsigned char)(sum_b / blurArea);
 973             if ( src_alpha )
 974                 dst_alpha[x + y * M_IMGDATA->m_width] = (unsigned char)(sum_a / blurArea);
 975         }
 976     }
 977
 978     return ret_image;
 979 }
 980
 981 // The new blur function
 982 wxImage wxImage::Blur(int blurRadius)
 983 {
 984     wxImage ret_image;
 985     ret_image.Create(M_IMGDATA->m_width, M_IMGDATA->m_height, false);
 986
 987     // Blur the image in each direction
 988     ret_image = BlurHorizontal(blurRadius);
 989     ret_image = ret_image.BlurVertical(blurRadius);
 990
 991     return ret_image;
 992 }
 993
 994 wxImage wxImage::Rotate90( bool clockwise ) const
 995 {
 996     wxImage image;
 997
 998     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
 999
1000     image.Create( M_IMGDATA->m_height, M_IMGDATA->m_width, false );
1001
1002     unsigned char *data = image.GetData();
1003
1004     wxCHECK_MSG( data, image, wxT("unable to create image") );
1005
1006     unsigned char *source_data = M_IMGDATA->m_data;
1007     unsigned char *target_data;
1008     unsigned char *alpha_data = 0 ;
1009     unsigned char *source_alpha = 0 ;
1010     unsigned char *target_alpha = 0 ;
1011
1012     if (M_IMGDATA->m_hasMask)
1013     {
1014         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
1015     }
1016     else
1017     {
1018         source_alpha = M_IMGDATA->m_alpha ;
1019         if ( source_alpha )
1020         {
1021             image.SetAlpha() ;
1022             alpha_data = image.GetAlpha() ;
1023         }
1024     }
1025
1026     long height = M_IMGDATA->m_height;
1027     long width  = M_IMGDATA->m_width;
1028
1029     for (long j = 0; j < height; j++)
1030     {
1031         for (long i = 0; i < width; i++)
1032         {
1033             if (clockwise)
1034             {
1035                 target_data = data + (((i+1)*height) - j - 1)*3;
1036                 if(source_alpha)
1037                     target_alpha = alpha_data + (((i+1)*height) - j - 1);
1038             }
1039             else
1040             {
1041                 target_data = data + ((height*(width-1)) + j - (i*height))*3;
1042                 if(source_alpha)
1043                     target_alpha = alpha_data + ((height*(width-1)) + j - (i*height));
1044             }
1045             memcpy( target_data, source_data, 3 );
1046             source_data += 3;
1047
1048             if(source_alpha)
1049             {
1050                 memcpy( target_alpha, source_alpha, 1 );
1051                 source_alpha += 1;
1052             }
1053         }
1054     }
1055
1056     return image;
1057 }
1058
1059 wxImage wxImage::Mirror( bool horizontally ) const
1060 {
1061     wxImage image;
1062
1063     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
1064
1065     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height, false );
1066
1067     unsigned char *data = image.GetData();
1068     unsigned char *alpha = NULL;
1069
1070     wxCHECK_MSG( data, image, wxT("unable to create image") );
1071
1072     if (M_IMGDATA->m_alpha != NULL) {
1073         image.SetAlpha();
1074         alpha = image.GetAlpha();
1075         wxCHECK_MSG( alpha, image, wxT("unable to create alpha channel") );
1076     }
1077
1078     if (M_IMGDATA->m_hasMask)
1079         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
1080
1081     long height = M_IMGDATA->m_height;
1082     long width  = M_IMGDATA->m_width;
1083
1084     unsigned char *source_data = M_IMGDATA->m_data;
1085     unsigned char *target_data;
1086
1087     if (horizontally)
1088     {
1089         for (long j = 0; j < height; j++)
1090         {
1091             data += width*3;
1092             target_data = data-3;
1093             for (long i = 0; i < width; i++)
1094             {
1095                 memcpy( target_data, source_data, 3 );
1096                 source_data += 3;
1097                 target_data -= 3;
1098             }
1099         }
1100
1101         if (alpha != NULL)
1102         {
1103             // src_alpha starts at the first pixel and increases by 1 after each step
1104             // (a step here is the copy of the alpha value of one pixel)
1105             const unsigned char *src_alpha = M_IMGDATA->m_alpha;
1106             // dest_alpha starts just beyond the first line, decreases before each step,
1107             // and after each line is finished, increases by 2 widths (skipping the line
1108             // just copied and the line that will be copied next)
1109             unsigned char *dest_alpha = alpha + width;
1110
1111             for (long jj = 0; jj < height; ++jj)
1112             {
1113                 for (long i = 0; i < width; ++i) {
1114                     *(--dest_alpha) = *(src_alpha++); // copy one pixel
1115                 }
1116                 dest_alpha += 2 * width; // advance beyond the end of the next line
1117             }
1118         }
1119     }
1120     else
1121     {
1122         for (long i = 0; i < height; i++)
1123         {
1124             target_data = data + 3*width*(height-1-i);
1125             memcpy( target_data, source_data, (size_t)3*width );
1126             source_data += 3*width;
1127         }
1128
1129         if (alpha != NULL)
1130         {
1131             // src_alpha starts at the first pixel and increases by 1 width after each step
1132             // (a step here is the copy of the alpha channel of an entire line)
1133             const unsigned char *src_alpha = M_IMGDATA->m_alpha;
1134             // dest_alpha starts just beyond the last line (beyond the whole image)
1135             // and decreases by 1 width before each step
1136             unsigned char *dest_alpha = alpha + width * height;
1137
1138             for (long jj = 0; jj < height; ++jj)
1139             {
1140                 dest_alpha -= width;
1141                 memcpy( dest_alpha, src_alpha, (size_t)width );
1142                 src_alpha += width;
1143             }
1144         }
1145     }
1146
1147     return image;
1148 }
1149
1150 wxImage wxImage::GetSubImage( const wxRect &rect ) const
1151 {
1152     wxImage image;
1153
1154     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
1155
1156     wxCHECK_MSG( (rect.GetLeft()>=0) && (rect.GetTop()>=0) &&
1157                  (rect.GetRight()<=GetWidth()) && (rect.GetBottom()<=GetHeight()),
1158                  image, wxT("invalid subimage size") );
1159
1160     const int subwidth = rect.GetWidth();
1161     const int subheight = rect.GetHeight();
1162
1163     image.Create( subwidth, subheight, false );
1164
1165     const unsigned char *src_data = GetData();
1166     const unsigned char *src_alpha = M_IMGDATA->m_alpha;
1167     unsigned char *subdata = image.GetData();
1168     unsigned char *subalpha = NULL;
1169
1170     wxCHECK_MSG( subdata, image, wxT("unable to create image") );
1171
1172     if (src_alpha != NULL) {
1173         image.SetAlpha();
1174         subalpha = image.GetAlpha();
1175         wxCHECK_MSG( subalpha, image, wxT("unable to create alpha channel"));
1176     }
1177
1178     if (M_IMGDATA->m_hasMask)
1179         image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
1180
1181     const int width = GetWidth();
1182     const int pixsoff = rect.GetLeft() + width * rect.GetTop();
1183
1184     src_data += 3 * pixsoff;
1185     src_alpha += pixsoff; // won't be used if was NULL, so this is ok
1186
1187     for (long j = 0; j < subheight; ++j)
1188     {
1189         memcpy( subdata, src_data, 3 * subwidth );
1190         subdata += 3 * subwidth;
1191         src_data += 3 * width;
1192         if (subalpha != NULL) {
1193             memcpy( subalpha, src_alpha, subwidth );
1194             subalpha += subwidth;
1195             src_alpha += width;
1196         }
1197     }
1198
1199     return image;
1200 }
1201
1202 wxImage wxImage::Size( const wxSize& size, const wxPoint& pos,
1203                        int r_, int g_, int b_ ) const
1204 {
1205     wxImage image;
1206
1207     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
1208     wxCHECK_MSG( (size.GetWidth() > 0) && (size.GetHeight() > 0), image, wxT("invalid size") );
1209
1210     int width = GetWidth(), height = GetHeight();
1211     image.Create(size.GetWidth(), size.GetHeight(), false);
1212
1213     unsigned char r = (unsigned char)r_;
1214     unsigned char g = (unsigned char)g_;
1215     unsigned char b = (unsigned char)b_;
1216     if ((r_ == -1) && (g_ == -1) && (b_ == -1))
1217     {
1218         GetOrFindMaskColour( &r, &g, &b );
1219         image.SetMaskColour(r, g, b);
1220     }
1221
1222     image.SetRGB(wxRect(), r, g, b);
1223
1224     wxRect subRect(pos.x, pos.y, width, height);
1225     wxRect finalRect(0, 0, size.GetWidth(), size.GetHeight());
1226     if (pos.x < 0)
1227         finalRect.width -= pos.x;
1228     if (pos.y < 0)
1229         finalRect.height -= pos.y;
1230
1231     subRect.Intersect(finalRect);
1232
1233     if (!subRect.IsEmpty())
1234     {
1235         if ((subRect.GetWidth() == width) && (subRect.GetHeight() == height))
1236             image.Paste(*this, pos.x, pos.y);
1237         else
1238             image.Paste(GetSubImage(subRect), pos.x, pos.y);
1239     }
1240
1241     return image;
1242 }
1243
1244 void wxImage::Paste( const wxImage &image, int x, int y )
1245 {
1246     wxCHECK_RET( Ok(), wxT("invalid image") );
1247     wxCHECK_RET( image.Ok(), wxT("invalid image") );
1248
1249     AllocExclusive();
1250
1251     int xx = 0;
1252     int yy = 0;
1253     int width = image.GetWidth();
1254     int height = image.GetHeight();
1255
1256     if (x < 0)
1257     {
1258         xx = -x;
1259         width += x;
1260     }
1261     if (y < 0)
1262     {
1263         yy = -y;
1264         height += y;
1265     }
1266
1267     if ((x+xx)+width > M_IMGDATA->m_width)
1268         width = M_IMGDATA->m_width - (x+xx);
1269     if ((y+yy)+height > M_IMGDATA->m_height)
1270         height = M_IMGDATA->m_height - (y+yy);
1271
1272     if (width < 1) return;
1273     if (height < 1) return;
1274
1275     if ((!HasMask() && !image.HasMask()) ||
1276         (HasMask() && !image.HasMask()) ||
1277        ((HasMask() && image.HasMask() &&
1278          (GetMaskRed()==image.GetMaskRed()) &&
1279          (GetMaskGreen()==image.GetMaskGreen()) &&
1280          (GetMaskBlue()==image.GetMaskBlue()))))
1281     {
1282         width *= 3;
1283         unsigned char* source_data = image.GetData() + xx*3 + yy*3*image.GetWidth();
1284         int source_step = image.GetWidth()*3;
1285
1286         unsigned char* target_data = GetData() + (x+xx)*3 + (y+yy)*3*M_IMGDATA->m_width;
1287         int target_step = M_IMGDATA->m_width*3;
1288         for (int j = 0; j < height; j++)
1289         {
1290             memcpy( target_data, source_data, width );
1291             source_data += source_step;
1292             target_data += target_step;
1293         }
1294         return;
1295     }
1296
1297     if (!HasMask() && image.HasMask())
1298     {
1299         unsigned char r = image.GetMaskRed();
1300         unsigned char g = image.GetMaskGreen();
1301         unsigned char b = image.GetMaskBlue();
1302
1303         width *= 3;
1304         unsigned char* source_data = image.GetData() + xx*3 + yy*3*image.GetWidth();
1305         int source_step = image.GetWidth()*3;
1306
1307         unsigned char* target_data = GetData() + (x+xx)*3 + (y+yy)*3*M_IMGDATA->m_width;
1308         int target_step = M_IMGDATA->m_width*3;
1309
1310         for (int j = 0; j < height; j++)
1311         {
1312             for (int i = 0; i < width; i+=3)
1313             {
1314                 if ((source_data[i]   != r) ||
1315                     (source_data[i+1] != g) ||
1316                     (source_data[i+2] != b))
1317                 {
1318                     memcpy( target_data+i, source_data+i, 3 );
1319                 }
1320             }
1321             source_data += source_step;
1322             target_data += target_step;
1323         }
1324     }
1325 }
1326
1327 void wxImage::Replace( unsigned char r1, unsigned char g1, unsigned char b1,
1328                        unsigned char r2, unsigned char g2, unsigned char b2 )
1329 {
1330     wxCHECK_RET( Ok(), wxT("invalid image") );
1331
1332     AllocExclusive();
1333
1334     unsigned char *data = GetData();
1335
1336     const int w = GetWidth();
1337     const int h = GetHeight();
1338
1339     for (int j = 0; j < h; j++)
1340         for (int i = 0; i < w; i++)
1341         {
1342             if ((data[0] == r1) && (data[1] == g1) && (data[2] == b1))
1343             {
1344                 data[0] = r2;
1345                 data[1] = g2;
1346                 data[2] = b2;
1347             }
1348             data += 3;
1349         }
1350 }
1351
1352 wxImage wxImage::ConvertToGreyscale( double lr, double lg, double lb ) const
1353 {
1354     wxImage image;
1355
1356     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
1357
1358     image.Create(M_IMGDATA->m_width, M_IMGDATA->m_height, false);
1359
1360     unsigned char *dest = image.GetData();
1361
1362     wxCHECK_MSG( dest, image, wxT("unable to create image") );
1363
1364     unsigned char *src = M_IMGDATA->m_data;
1365     bool hasMask = M_IMGDATA->m_hasMask;
1366     unsigned char maskRed = M_IMGDATA->m_maskRed;
1367     unsigned char maskGreen = M_IMGDATA->m_maskGreen;
1368     unsigned char maskBlue = M_IMGDATA->m_maskBlue;
1369
1370     if ( hasMask )
1371         image.SetMaskColour(maskRed, maskGreen, maskBlue);
1372
1373     const long size = M_IMGDATA->m_width * M_IMGDATA->m_height;
1374     for ( long i = 0; i < size; i++, src += 3, dest += 3 )
1375     {
1376         // don't modify the mask
1377         if ( hasMask && src[0] == maskRed && src[1] == maskGreen && src[2] == maskBlue )
1378         {
1379             memcpy(dest, src, 3);
1380         }
1381         else
1382         {
1383             // calculate the luma
1384             double luma = (src[0] * lr + src[1] * lg + src[2] * lb) + 0.5;
1385             dest[0] = dest[1] = dest[2] = wx_static_cast(unsigned char, luma);
1386         }
1387     }
1388
1389     // copy the alpha channel, if any
1390     if (HasAlpha())
1391     {
1392         const size_t alphaSize = GetWidth() * GetHeight();
1393         unsigned char *alpha = (unsigned char*)malloc(alphaSize);
1394         memcpy(alpha, GetAlpha(), alphaSize);
1395         image.InitAlpha();
1396         image.SetAlpha(alpha);
1397     }
1398
1399     return image;
1400 }
1401
1402 wxImage wxImage::ConvertToMono( unsigned char r, unsigned char g, unsigned char b ) const
1403 {
1404     wxImage image;
1405
1406     wxCHECK_MSG( Ok(), image, wxT("invalid image") );
1407
1408     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height, false );
1409
1410     unsigned char *data = image.GetData();
1411
1412     wxCHECK_MSG( data, image, wxT("unable to create image") );
1413
1414     if (M_IMGDATA->m_hasMask)
1415     {
1416         if (M_IMGDATA->m_maskRed == r && M_IMGDATA->m_maskGreen == g &&
1417                                          M_IMGDATA->m_maskBlue == b)
1418             image.SetMaskColour( 255, 255, 255 );
1419         else
1420             image.SetMaskColour( 0, 0, 0 );
1421     }
1422
1423     long size = M_IMGDATA->m_height * M_IMGDATA->m_width;
1424
1425     unsigned char *srcd = M_IMGDATA->m_data;
1426     unsigned char *tard = image.GetData();
1427
1428     for ( long i = 0; i < size; i++, srcd += 3, tard += 3 )
1429     {
1430         if (srcd[0] == r && srcd[1] == g && srcd[2] == b)
1431             tard[0] = tard[1] = tard[2] = 255;
1432         else
1433             tard[0] = tard[1] = tard[2] = 0;
1434     }
1435
1436     return image;
1437 }
1438
1439 int wxImage::GetWidth() const
1440 {
1441     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
1442
1443     return M_IMGDATA->m_width;
1444 }
1445
1446 int wxImage::GetHeight() const
1447 {
1448     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
1449
1450     return M_IMGDATA->m_height;
1451 }
1452
1453 long wxImage::XYToIndex(int x, int y) const
1454 {
1455     if ( Ok() &&
1456             x >= 0 && y >= 0 &&
1457                 x < M_IMGDATA->m_width && y < M_IMGDATA->m_height )
1458     {
1459         return y*M_IMGDATA->m_width + x;
1460     }
1461
1462     return -1;
1463 }
1464
1465 void wxImage::SetRGB( int x, int y, unsigned char r, unsigned char g, unsigned char b )
1466 {
1467     long pos = XYToIndex(x, y);
1468     wxCHECK_RET( pos != -1, wxT("invalid image coordinates") );
1469
1470     AllocExclusive();
1471
1472     pos *= 3;
1473
1474     M_IMGDATA->m_data[ pos   ] = r;
1475     M_IMGDATA->m_data[ pos+1 ] = g;
1476     M_IMGDATA->m_data[ pos+2 ] = b;
1477 }
1478
1479 void wxImage::SetRGB( const wxRect& rect_, unsigned char r, unsigned char g, unsigned char b )
1480 {
1481     wxCHECK_RET( Ok(), wxT("invalid image") );
1482
1483     AllocExclusive();
1484
1485     wxRect rect(rect_);
1486     wxRect imageRect(0, 0, GetWidth(), GetHeight());
1487     if ( rect == wxRect() )
1488     {
1489         rect = imageRect;
1490     }
1491     else
1492     {
1493         wxCHECK_RET( imageRect.Contains(rect.GetTopLeft()) &&
1494                      imageRect.Contains(rect.GetBottomRight()),
1495                      wxT("invalid bounding rectangle") );
1496     }
1497
1498     int x1 = rect.GetLeft(),
1499         y1 = rect.GetTop(),
1500         x2 = rect.GetRight() + 1,
1501         y2 = rect.GetBottom() + 1;
1502
1503     unsigned char *data wxDUMMY_INITIALIZE(NULL);
1504     int x, y, width = GetWidth();
1505     for (y = y1; y < y2; y++)
1506     {
1507         data = M_IMGDATA->m_data + (y*width + x1)*3;
1508         for (x = x1; x < x2; x++)
1509         {
1510             *data++ = r;
1511             *data++ = g;
1512             *data++ = b;
1513         }
1514     }
1515 }
1516
1517 unsigned char wxImage::GetRed( int x, int y ) const
1518 {
1519     long pos = XYToIndex(x, y);
1520     wxCHECK_MSG( pos != -1, 0, wxT("invalid image coordinates") );
1521
1522     pos *= 3;
1523
1524     return M_IMGDATA->m_data[pos];
1525 }
1526
1527 unsigned char wxImage::GetGreen( int x, int y ) const
1528 {
1529     long pos = XYToIndex(x, y);
1530     wxCHECK_MSG( pos != -1, 0, wxT("invalid image coordinates") );
1531
1532     pos *= 3;
1533
1534     return M_IMGDATA->m_data[pos+1];
1535 }
1536
1537 unsigned char wxImage::GetBlue( int x, int y ) const
1538 {
1539     long pos = XYToIndex(x, y);
1540     wxCHECK_MSG( pos != -1, 0, wxT("invalid image coordinates") );
1541
1542     pos *= 3;
1543
1544     return M_IMGDATA->m_data[pos+2];
1545 }
1546
1547 bool wxImage::IsOk() const
1548 {
1549     // image of 0 width or height can't be considered ok - at least because it
1550     // causes crashes in ConvertToBitmap() if we don't catch it in time
1551     wxImageRefData *data = M_IMGDATA;
1552     return data && data->m_ok && data->m_width && data->m_height;
1553 }
1554
1555 unsigned char *wxImage::GetData() const
1556 {
1557     wxCHECK_MSG( Ok(), (unsigned char *)NULL, wxT("invalid image") );
1558
1559     return M_IMGDATA->m_data;
1560 }
1561
1562 void wxImage::SetData( unsigned char *data, bool static_data  )
1563 {
1564     wxCHECK_RET( Ok(), wxT("invalid image") );
1565
1566     wxImageRefData *newRefData = new wxImageRefData();
1567
1568     newRefData->m_width = M_IMGDATA->m_width;
1569     newRefData->m_height = M_IMGDATA->m_height;
1570     newRefData->m_data = data;
1571     newRefData->m_ok = true;
1572     newRefData->m_maskRed = M_IMGDATA->m_maskRed;
1573     newRefData->m_maskGreen = M_IMGDATA->m_maskGreen;
1574     newRefData->m_maskBlue = M_IMGDATA->m_maskBlue;
1575     newRefData->m_hasMask = M_IMGDATA->m_hasMask;
1576     newRefData->m_static = static_data;
1577
1578     UnRef();
1579
1580     m_refData = newRefData;
1581 }
1582
1583 void wxImage::SetData( unsigned char *data, int new_width, int new_height, bool static_data )
1584 {
1585     wxImageRefData *newRefData = new wxImageRefData();
1586
1587     if (m_refData)
1588     {
1589         newRefData->m_width = new_width;
1590         newRefData->m_height = new_height;
1591         newRefData->m_data = data;
1592         newRefData->m_ok = true;
1593         newRefData->m_maskRed = M_IMGDATA->m_maskRed;
1594         newRefData->m_maskGreen = M_IMGDATA->m_maskGreen;
1595         newRefData->m_maskBlue = M_IMGDATA->m_maskBlue;
1596         newRefData->m_hasMask = M_IMGDATA->m_hasMask;
1597     }
1598     else
1599     {
1600         newRefData->m_width = new_width;
1601         newRefData->m_height = new_height;
1602         newRefData->m_data = data;
1603         newRefData->m_ok = true;
1604     }
1605     newRefData->m_static = static_data;
1606
1607     UnRef();
1608
1609     m_refData = newRefData;
1610 }
1611
1612 // ----------------------------------------------------------------------------
1613 // alpha channel support
1614 // ----------------------------------------------------------------------------
1615
1616 void wxImage::SetAlpha(int x, int y, unsigned char alpha)
1617 {
1618     wxCHECK_RET( HasAlpha(), wxT("no alpha channel") );
1619
1620     long pos = XYToIndex(x, y);
1621     wxCHECK_RET( pos != -1, wxT("invalid image coordinates") );
1622
1623     AllocExclusive();
1624
1625     M_IMGDATA->m_alpha[pos] = alpha;
1626 }
1627
1628 unsigned char wxImage::GetAlpha(int x, int y) const
1629 {
1630     wxCHECK_MSG( HasAlpha(), 0, wxT("no alpha channel") );
1631
1632     long pos = XYToIndex(x, y);
1633     wxCHECK_MSG( pos != -1, 0, wxT("invalid image coordinates") );
1634
1635     return M_IMGDATA->m_alpha[pos];
1636 }
1637
1638 bool
1639 wxImage::ConvertColourToAlpha(unsigned char r, unsigned char g, unsigned char b)
1640 {
1641     SetAlpha(NULL);
1642
1643     const int w = M_IMGDATA->m_width;
1644     const int h = M_IMGDATA->m_height;
1645
1646     unsigned char *alpha = GetAlpha();
1647     unsigned char *data = GetData();
1648
1649     for ( int y = 0; y < h; y++ )
1650     {
1651         for ( int x = 0; x < w; x++ )
1652         {
1653             *alpha++ = *data;
1654             *data++ = r;
1655             *data++ = g;
1656             *data++ = b;
1657         }
1658     }
1659
1660     return true;
1661 }
1662
1663 void wxImage::SetAlpha( unsigned char *alpha, bool static_data )
1664 {
1665     wxCHECK_RET( Ok(), wxT("invalid image") );
1666
1667     AllocExclusive();
1668
1669     if ( !alpha )
1670     {
1671         alpha = (unsigned char *)malloc(M_IMGDATA->m_width*M_IMGDATA->m_height);
1672     }
1673
1674     free(M_IMGDATA->m_alpha);
1675     M_IMGDATA->m_alpha = alpha;
1676     M_IMGDATA->m_staticAlpha = static_data;
1677 }
1678
1679 unsigned char *wxImage::GetAlpha() const
1680 {
1681     wxCHECK_MSG( Ok(), (unsigned char *)NULL, wxT("invalid image") );
1682
1683     return M_IMGDATA->m_alpha;
1684 }
1685
1686 void wxImage::InitAlpha()
1687 {
1688     wxCHECK_RET( !HasAlpha(), wxT("image already has an alpha channel") );
1689
1690     // initialize memory for alpha channel
1691     SetAlpha();
1692
1693     unsigned char *alpha = M_IMGDATA->m_alpha;
1694     const size_t lenAlpha = M_IMGDATA->m_width * M_IMGDATA->m_height;
1695
1696     if ( HasMask() )
1697     {
1698         // use the mask to initialize the alpha channel.
1699         const unsigned char * const alphaEnd = alpha + lenAlpha;
1700
1701         const unsigned char mr = M_IMGDATA->m_maskRed;
1702         const unsigned char mg = M_IMGDATA->m_maskGreen;
1703         const unsigned char mb = M_IMGDATA->m_maskBlue;
1704         for ( unsigned char *src = M_IMGDATA->m_data;
1705               alpha < alphaEnd;
1706               src += 3, alpha++ )
1707         {
1708             *alpha = (src[0] == mr && src[1] == mg && src[2] == mb)
1709                             ? wxIMAGE_ALPHA_TRANSPARENT
1710                             : wxIMAGE_ALPHA_OPAQUE;
1711         }
1712
1713         M_IMGDATA->m_hasMask = false;
1714     }
1715     else // no mask
1716     {
1717         // make the image fully opaque
1718         memset(alpha, wxIMAGE_ALPHA_OPAQUE, lenAlpha);
1719     }
1720 }
1721
1722 // ----------------------------------------------------------------------------
1723 // mask support
1724 // ----------------------------------------------------------------------------
1725
1726 void wxImage::SetMaskColour( unsigned char r, unsigned char g, unsigned char b )
1727 {
1728     wxCHECK_RET( Ok(), wxT("invalid image") );
1729
1730     AllocExclusive();
1731
1732     M_IMGDATA->m_maskRed = r;
1733     M_IMGDATA->m_maskGreen = g;
1734     M_IMGDATA->m_maskBlue = b;
1735     M_IMGDATA->m_hasMask = true;
1736 }
1737
1738 bool wxImage::GetOrFindMaskColour( unsigned char *r, unsigned char *g, unsigned char *b ) const
1739 {
1740     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
1741
1742     if (M_IMGDATA->m_hasMask)
1743     {
1744         if (r) *r = M_IMGDATA->m_maskRed;
1745         if (g) *g = M_IMGDATA->m_maskGreen;
1746         if (b) *b = M_IMGDATA->m_maskBlue;
1747         return true;
1748     }
1749     else
1750     {
1751         FindFirstUnusedColour(r, g, b);
1752         return false;
1753     }
1754 }
1755
1756 unsigned char wxImage::GetMaskRed() const
1757 {
1758     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
1759
1760     return M_IMGDATA->m_maskRed;
1761 }
1762
1763 unsigned char wxImage::GetMaskGreen() const
1764 {
1765     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
1766
1767     return M_IMGDATA->m_maskGreen;
1768 }
1769
1770 unsigned char wxImage::GetMaskBlue() const
1771 {
1772     wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
1773
1774     return M_IMGDATA->m_maskBlue;
1775 }
1776
1777 void wxImage::SetMask( bool mask )
1778 {
1779     wxCHECK_RET( Ok(), wxT("invalid image") );
1780
1781     AllocExclusive();
1782
1783     M_IMGDATA->m_hasMask = mask;
1784 }
1785
1786 bool wxImage::HasMask() const
1787 {
1788     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
1789
1790     return M_IMGDATA->m_hasMask;
1791 }
1792
1793 bool wxImage::IsTransparent(int x, int y, unsigned char threshold) const
1794 {
1795     long pos = XYToIndex(x, y);
1796     wxCHECK_MSG( pos != -1, false, wxT("invalid image coordinates") );
1797
1798     // check mask
1799     if ( M_IMGDATA->m_hasMask )
1800     {
1801         const unsigned char *p = M_IMGDATA->m_data + 3*pos;
1802         if ( p[0] == M_IMGDATA->m_maskRed &&
1803                 p[1] == M_IMGDATA->m_maskGreen &&
1804                     p[2] == M_IMGDATA->m_maskBlue )
1805         {
1806             return true;
1807         }
1808     }
1809
1810     // then check alpha
1811     if ( M_IMGDATA->m_alpha )
1812     {
1813         if ( M_IMGDATA->m_alpha[pos] < threshold )
1814         {
1815             // transparent enough
1816             return true;
1817         }
1818     }
1819
1820     // not transparent
1821     return false;
1822 }
1823
1824 bool wxImage::SetMaskFromImage(const wxImage& mask,
1825                                unsigned char mr, unsigned char mg, unsigned char mb)
1826 {
1827     // check that the images are the same size
1828     if ( (M_IMGDATA->m_height != mask.GetHeight() ) || (M_IMGDATA->m_width != mask.GetWidth () ) )
1829     {
1830         wxLogError( _("Image and mask have different sizes.") );
1831         return false;
1832     }
1833
1834     // find unused colour
1835     unsigned char r,g,b ;
1836     if (!FindFirstUnusedColour(&r, &g, &b))
1837     {
1838         wxLogError( _("No unused colour in image being masked.") );
1839         return false ;
1840     }
1841
1842     AllocExclusive();
1843
1844     unsigned char *imgdata = GetData();
1845     unsigned char *maskdata = mask.GetData();
1846
1847     const int w = GetWidth();
1848     const int h = GetHeight();
1849
1850     for (int j = 0; j < h; j++)
1851     {
1852         for (int i = 0; i < w; i++)
1853         {
1854             if ((maskdata[0] == mr) && (maskdata[1]  == mg) && (maskdata[2] == mb))
1855             {
1856                 imgdata[0] = r;
1857                 imgdata[1] = g;
1858                 imgdata[2] = b;
1859             }
1860             imgdata  += 3;
1861             maskdata += 3;
1862         }
1863     }
1864
1865     SetMaskColour(r, g, b);
1866     SetMask(true);
1867
1868     return true;
1869 }
1870
1871 bool wxImage::ConvertAlphaToMask(unsigned char threshold)
1872 {
1873     if (!HasAlpha())
1874         return true;
1875
1876     unsigned char mr, mg, mb;
1877     if (!FindFirstUnusedColour(&mr, &mg, &mb))
1878     {
1879         wxLogError( _("No unused colour in image being masked.") );
1880         return false;
1881     }
1882
1883     AllocExclusive();
1884
1885     SetMask(true);
1886     SetMaskColour(mr, mg, mb);
1887
1888     unsigned char *imgdata = GetData();
1889     unsigned char *alphadata = GetAlpha();
1890
1891     int w = GetWidth();
1892     int h = GetHeight();
1893
1894     for (int y = 0; y < h; y++)
1895     {
1896         for (int x = 0; x < w; x++, imgdata += 3, alphadata++)
1897         {
1898             if (*alphadata < threshold)
1899             {
1900                 imgdata[0] = mr;
1901                 imgdata[1] = mg;
1902                 imgdata[2] = mb;
1903             }
1904         }
1905     }
1906
1907     free(M_IMGDATA->m_alpha);
1908     M_IMGDATA->m_alpha = NULL;
1909
1910     return true;
1911 }
1912
1913 // ----------------------------------------------------------------------------
1914 // Palette functions
1915 // ----------------------------------------------------------------------------
1916
1917 #if wxUSE_PALETTE
1918
1919 bool wxImage::HasPalette() const
1920 {
1921     if (!Ok())
1922         return false;
1923
1924     return M_IMGDATA->m_palette.Ok();
1925 }
1926
1927 const wxPalette& wxImage::GetPalette() const
1928 {
1929     wxCHECK_MSG( Ok(), wxNullPalette, wxT("invalid image") );
1930
1931     return M_IMGDATA->m_palette;
1932 }
1933
1934 void wxImage::SetPalette(const wxPalette& palette)
1935 {
1936     wxCHECK_RET( Ok(), wxT("invalid image") );
1937
1938     AllocExclusive();
1939
1940     M_IMGDATA->m_palette = palette;
1941 }
1942
1943 #endif // wxUSE_PALETTE
1944
1945 // ----------------------------------------------------------------------------
1946 // Option functions (arbitrary name/value mapping)
1947 // ----------------------------------------------------------------------------
1948
1949 void wxImage::SetOption(const wxString& name, const wxString& value)
1950 {
1951     wxCHECK_RET( Ok(), wxT("invalid image") );
1952
1953     AllocExclusive();
1954
1955     int idx = M_IMGDATA->m_optionNames.Index(name, false);
1956     if (idx == wxNOT_FOUND)
1957     {
1958         M_IMGDATA->m_optionNames.Add(name);
1959         M_IMGDATA->m_optionValues.Add(value);
1960     }
1961     else
1962     {
1963         M_IMGDATA->m_optionNames[idx] = name;
1964         M_IMGDATA->m_optionValues[idx] = value;
1965     }
1966 }
1967
1968 void wxImage::SetOption(const wxString& name, int value)
1969 {
1970     wxString valStr;
1971     valStr.Printf(wxT("%d"), value);
1972     SetOption(name, valStr);
1973 }
1974
1975 wxString wxImage::GetOption(const wxString& name) const
1976 {
1977     wxCHECK_MSG( Ok(), wxEmptyString, wxT("invalid image") );
1978
1979     int idx = M_IMGDATA->m_optionNames.Index(name, false);
1980     if (idx == wxNOT_FOUND)
1981         return wxEmptyString;
1982     else
1983         return M_IMGDATA->m_optionValues[idx];
1984 }
1985
1986 int wxImage::GetOptionInt(const wxString& name) const
1987 {
1988     return wxAtoi(GetOption(name));
1989 }
1990
1991 bool wxImage::HasOption(const wxString& name) const
1992 {
1993     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
1994
1995     return (M_IMGDATA->m_optionNames.Index(name, false) != wxNOT_FOUND);
1996 }
1997
1998 // ----------------------------------------------------------------------------
1999 // image I/O
2000 // ----------------------------------------------------------------------------
2001
2002 bool wxImage::LoadFile( const wxString& WXUNUSED_UNLESS_STREAMS(filename),
2003                         long WXUNUSED_UNLESS_STREAMS(type),
2004                         int WXUNUSED_UNLESS_STREAMS(index) )
2005 {
2006 #if HAS_FILE_STREAMS
2007     if (wxFileExists(filename))
2008     {
2009         wxImageFileInputStream stream(filename);
2010         wxBufferedInputStream bstream( stream );
2011         return LoadFile(bstream, type, index);
2012     }
2013     else
2014     {
2015         wxLogError( _("Can't load image from file '%s': file does not exist."), filename.c_str() );
2016
2017         return false;
2018     }
2019 #else // !HAS_FILE_STREAMS
2020     return false;
2021 #endif // HAS_FILE_STREAMS
2022 }
2023
2024 bool wxImage::LoadFile( const wxString& WXUNUSED_UNLESS_STREAMS(filename),
2025                         const wxString& WXUNUSED_UNLESS_STREAMS(mimetype),
2026                         int WXUNUSED_UNLESS_STREAMS(index) )
2027 {
2028 #if HAS_FILE_STREAMS
2029     if (wxFileExists(filename))
2030     {
2031         wxImageFileInputStream stream(filename);
2032         wxBufferedInputStream bstream( stream );
2033         return LoadFile(bstream, mimetype, index);
2034     }
2035     else
2036     {
2037         wxLogError( _("Can't load image from file '%s': file does not exist."), filename.c_str() );
2038
2039         return false;
2040     }
2041 #else // !HAS_FILE_STREAMS
2042     return false;
2043 #endif // HAS_FILE_STREAMS
2044 }
2045
2046
2047
2048 bool wxImage::SaveFile( const wxString& filename ) const
2049 {
2050     wxString ext = filename.AfterLast('.').Lower();
2051
2052     wxImageHandler * pHandler = FindHandler(ext, -1);
2053     if (pHandler)
2054     {
2055         SaveFile(filename, pHandler->GetType());
2056         return true;
2057     }
2058
2059     wxLogError(_("Can't save image to file '%s': unknown extension."), filename.c_str());
2060
2061     return false;
2062 }
2063
2064 bool wxImage::SaveFile( const wxString& WXUNUSED_UNLESS_STREAMS(filename),
2065                         int WXUNUSED_UNLESS_STREAMS(type) ) const
2066 {
2067 #if HAS_FILE_STREAMS
2068     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
2069
2070     ((wxImage*)this)->SetOption(wxIMAGE_OPTION_FILENAME, filename);
2071
2072     wxImageFileOutputStream stream(filename);
2073
2074     if ( stream.IsOk() )
2075     {
2076         wxBufferedOutputStream bstream( stream );
2077         return SaveFile(bstream, type);
2078     }
2079 #endif // HAS_FILE_STREAMS
2080
2081     return false;
2082 }
2083
2084 bool wxImage::SaveFile( const wxString& WXUNUSED_UNLESS_STREAMS(filename),
2085                         const wxString& WXUNUSED_UNLESS_STREAMS(mimetype) ) const
2086 {
2087 #if HAS_FILE_STREAMS
2088     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
2089
2090     ((wxImage*)this)->SetOption(wxIMAGE_OPTION_FILENAME, filename);
2091
2092     wxImageFileOutputStream stream(filename);
2093
2094     if ( stream.IsOk() )
2095     {
2096         wxBufferedOutputStream bstream( stream );
2097         return SaveFile(bstream, mimetype);
2098     }
2099 #endif // HAS_FILE_STREAMS
2100
2101     return false;
2102 }
2103
2104 bool wxImage::CanRead( const wxString& WXUNUSED_UNLESS_STREAMS(name) )
2105 {
2106 #if HAS_FILE_STREAMS
2107     wxImageFileInputStream stream(name);
2108     return CanRead(stream);
2109 #else
2110     return false;
2111 #endif
2112 }
2113
2114 int wxImage::GetImageCount( const wxString& WXUNUSED_UNLESS_STREAMS(name),
2115                             long WXUNUSED_UNLESS_STREAMS(type) )
2116 {
2117 #if HAS_FILE_STREAMS
2118     wxImageFileInputStream stream(name);
2119     if (stream.Ok())
2120         return GetImageCount(stream, type);
2121 #endif
2122
2123   return 0;
2124 }
2125
2126 #if wxUSE_STREAMS
2127
2128 bool wxImage::CanRead( wxInputStream &stream )
2129 {
2130     const wxList& list = GetHandlers();
2131
2132     for ( wxList::compatibility_iterator node = list.GetFirst(); node; node = node->GetNext() )
2133     {
2134         wxImageHandler *handler=(wxImageHandler*)node->GetData();
2135         if (handler->CanRead( stream ))
2136             return true;
2137     }
2138
2139     return false;
2140 }
2141
2142 int wxImage::GetImageCount( wxInputStream &stream, long type )
2143 {
2144     wxImageHandler *handler;
2145
2146     if ( type == wxBITMAP_TYPE_ANY )
2147     {
2148         wxList &list=GetHandlers();
2149
2150         for (wxList::compatibility_iterator node = list.GetFirst(); node; node = node->GetNext())
2151         {
2152              handler=(wxImageHandler*)node->GetData();
2153              if ( handler->CanRead(stream) )
2154                  return handler->GetImageCount(stream);
2155
2156         }
2157
2158         wxLogWarning(_("No handler found for image type."));
2159         return 0;
2160     }
2161
2162     handler = FindHandler(type);
2163
2164     if ( !handler )
2165     {
2166         wxLogWarning(_("No image handler for type %ld defined."), type);
2167         return false;
2168     }
2169
2170     if ( handler->CanRead(stream) )
2171     {
2172         return handler->GetImageCount(stream);
2173     }
2174     else
2175     {
2176         wxLogError(_("Image file is not of type %ld."), type);
2177         return 0;
2178     }
2179 }
2180
2181 bool wxImage::LoadFile( wxInputStream& stream, long type, int index )
2182 {
2183     UnRef();
2184
2185     m_refData = new wxImageRefData;
2186
2187     wxImageHandler *handler;
2188
2189     if ( type == wxBITMAP_TYPE_ANY )
2190     {
2191         wxList &list=GetHandlers();
2192
2193         for ( wxList::compatibility_iterator node = list.GetFirst(); node; node = node->GetNext() )
2194         {
2195              handler=(wxImageHandler*)node->GetData();
2196              if ( handler->CanRead(stream) )
2197                  return handler->LoadFile(this, stream, true/*verbose*/, index);
2198
2199         }
2200
2201         wxLogWarning( _("No handler found for image type.") );
2202         return false;
2203     }
2204
2205     handler = FindHandler(type);
2206
2207     if (handler == 0)
2208     {
2209         wxLogWarning( _("No image handler for type %ld defined."), type );
2210
2211         return false;
2212     }
2213
2214     if (stream.IsSeekable() && !handler->CanRead(stream))
2215     {
2216         wxLogError(_("Image file is not of type %ld."), type);
2217         return false;
2218     }
2219     else
2220         return handler->LoadFile(this, stream, true/*verbose*/, index);
2221 }
2222
2223 bool wxImage::LoadFile( wxInputStream& stream, const wxString& mimetype, int index )
2224 {
2225     UnRef();
2226
2227     m_refData = new wxImageRefData;
2228
2229     wxImageHandler *handler = FindHandlerMime(mimetype);
2230
2231     if (handler == 0)
2232     {
2233         wxLogWarning( _("No image handler for type %s defined."), mimetype.GetData() );
2234
2235         return false;
2236     }
2237
2238     if (stream.IsSeekable() && !handler->CanRead(stream))
2239     {
2240         wxLogError(_("Image file is not of type %s."), (const wxChar*) mimetype);
2241         return false;
2242     }
2243     else
2244         return handler->LoadFile( this, stream, true/*verbose*/, index );
2245 }
2246
2247 bool wxImage::SaveFile( wxOutputStream& stream, int type ) const
2248 {
2249     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
2250
2251     wxImageHandler *handler = FindHandler(type);
2252     if ( !handler )
2253     {
2254         wxLogWarning( _("No image handler for type %d defined."), type );
2255
2256         return false;
2257     }
2258
2259     return handler->SaveFile( (wxImage*)this, stream );
2260 }
2261
2262 bool wxImage::SaveFile( wxOutputStream& stream, const wxString& mimetype ) const
2263 {
2264     wxCHECK_MSG( Ok(), false, wxT("invalid image") );
2265
2266     wxImageHandler *handler = FindHandlerMime(mimetype);
2267     if ( !handler )
2268     {
2269         wxLogWarning( _("No image handler for type %s defined."), mimetype.GetData() );
2270
2271         return false;
2272     }
2273
2274     return handler->SaveFile( (wxImage*)this, stream );
2275 }
2276 #endif // wxUSE_STREAMS
2277
2278 // ----------------------------------------------------------------------------
2279 // image I/O handlers
2280 // ----------------------------------------------------------------------------
2281
2282 void wxImage::AddHandler( wxImageHandler *handler )
2283 {
2284     // Check for an existing handler of the type being added.
2285     if (FindHandler( handler->GetType() ) == 0)
2286     {
2287         sm_handlers.Append( handler );
2288     }
2289     else
2290     {
2291         // This is not documented behaviour, merely the simplest 'fix'
2292         // for preventing duplicate additions.  If someone ever has
2293         // a good reason to add and remove duplicate handlers (and they
2294         // may) we should probably refcount the duplicates.
2295         //   also an issue in InsertHandler below.
2296
2297         wxLogDebug( _T("Adding duplicate image handler for '%s'"),
2298                     handler->GetName().c_str() );
2299         delete handler;
2300     }
2301 }
2302
2303 void wxImage::InsertHandler( wxImageHandler *handler )
2304 {
2305     // Check for an existing handler of the type being added.
2306     if (FindHandler( handler->GetType() ) == 0)
2307     {
2308         sm_handlers.Insert( handler );
2309     }
2310     else
2311     {
2312         // see AddHandler for additional comments.
2313         wxLogDebug( _T("Inserting duplicate image handler for '%s'"),
2314                     handler->GetName().c_str() );
2315         delete handler;
2316     }
2317 }
2318
2319 bool wxImage::RemoveHandler( const wxString& name )
2320 {
2321     wxImageHandler *handler = FindHandler(name);
2322     if (handler)
2323     {
2324         sm_handlers.DeleteObject(handler);
2325         delete handler;
2326         return true;
2327     }
2328     else
2329         return false;
2330 }
2331
2332 wxImageHandler *wxImage::FindHandler( const wxString& name )
2333 {
2334     wxList::compatibility_iterator node = sm_handlers.GetFirst();
2335     while (node)
2336     {
2337         wxImageHandler *handler = (wxImageHandler*)node->GetData();
2338         if (handler->GetName().Cmp(name) == 0) return handler;
2339
2340         node = node->GetNext();
2341     }
2342     return 0;
2343 }
2344
2345 wxImageHandler *wxImage::FindHandler( const wxString& extension, long bitmapType )
2346 {
2347     wxList::compatibility_iterator node = sm_handlers.GetFirst();
2348     while (node)
2349     {
2350         wxImageHandler *handler = (wxImageHandler*)node->GetData();
2351         if ( (handler->GetExtension().Cmp(extension) == 0) &&
2352             (bitmapType == -1 || handler->GetType() == bitmapType) )
2353             return handler;
2354         node = node->GetNext();
2355     }
2356     return 0;
2357 }
2358
2359 wxImageHandler *wxImage::FindHandler( long bitmapType )
2360 {
2361     wxList::compatibility_iterator node = sm_handlers.GetFirst();
2362     while (node)
2363     {
2364         wxImageHandler *handler = (wxImageHandler *)node->GetData();
2365         if (handler->GetType() == bitmapType) return handler;
2366         node = node->GetNext();
2367     }
2368     return 0;
2369 }
2370
2371 wxImageHandler *wxImage::FindHandlerMime( const wxString& mimetype )
2372 {
2373     wxList::compatibility_iterator node = sm_handlers.GetFirst();
2374     while (node)
2375     {
2376         wxImageHandler *handler = (wxImageHandler *)node->GetData();
2377         if (handler->GetMimeType().IsSameAs(mimetype, false)) return handler;
2378         node = node->GetNext();
2379     }
2380     return 0;
2381 }
2382
2383 void wxImage::InitStandardHandlers()
2384 {
2385 #if wxUSE_STREAMS
2386     AddHandler(new wxBMPHandler);
2387 #endif // wxUSE_STREAMS
2388 }
2389
2390 void wxImage::CleanUpHandlers()
2391 {
2392     wxList::compatibility_iterator node = sm_handlers.GetFirst();
2393     while (node)
2394     {
2395         wxImageHandler *handler = (wxImageHandler *)node->GetData();
2396         wxList::compatibility_iterator next = node->GetNext();
2397         delete handler;
2398         node = next;
2399     }
2400
2401     sm_handlers.Clear();
2402 }
2403
2404 wxString wxImage::GetImageExtWildcard()
2405 {
2406     wxString fmts;
2407
2408     wxList& Handlers = wxImage::GetHandlers();
2409     wxList::compatibility_iterator Node = Handlers.GetFirst();
2410     while ( Node )
2411     {
2412         wxImageHandler* Handler = (wxImageHandler*)Node->GetData();
2413         fmts += wxT("*.") + Handler->GetExtension();
2414         Node = Node->GetNext();
2415         if ( Node ) fmts += wxT(";");
2416     }
2417
2418     return wxT("(") + fmts + wxT(")|") + fmts;
2419 }
2420
2421 wxImage::HSVValue wxImage::RGBtoHSV(const RGBValue& rgb)
2422 {
2423     const double red = rgb.red / 255.0,
2424                  green = rgb.green / 255.0,
2425                  blue = rgb.blue / 255.0;
2426
2427     // find the min and max intensity (and remember which one was it for the
2428     // latter)
2429     double minimumRGB = red;
2430     if ( green < minimumRGB )
2431         minimumRGB = green;
2432     if ( blue < minimumRGB )
2433         minimumRGB = blue;
2434
2435     enum { RED, GREEN, BLUE } chMax = RED;
2436     double maximumRGB = red;
2437     if ( green > maximumRGB )
2438     {
2439         chMax = GREEN;
2440         maximumRGB = green;
2441     }
2442     if ( blue > maximumRGB )
2443     {
2444         chMax = BLUE;
2445         maximumRGB = blue;
2446     }
2447
2448     const double value = maximumRGB;
2449
2450     double hue = 0.0, saturation;
2451     const double deltaRGB = maximumRGB - minimumRGB;
2452     if ( wxIsNullDouble(deltaRGB) )
2453     {
2454         // Gray has no color
2455         hue = 0.0;
2456         saturation = 0.0;
2457     }
2458     else
2459     {
2460         switch ( chMax )
2461         {
2462             case RED:
2463                 hue = (green - blue) / deltaRGB;
2464                 break;
2465
2466             case GREEN:
2467                 hue = 2.0 + (blue - red) / deltaRGB;
2468                 break;
2469
2470             case BLUE:
2471                 hue = 4.0 + (red - green) / deltaRGB;
2472                 break;
2473
2474             default:
2475                 wxFAIL_MSG(wxT("hue not specified"));
2476                 break;
2477         }
2478
2479         hue /= 6.0;
2480
2481         if ( hue < 0.0 )
2482             hue += 1.0;
2483
2484         saturation = deltaRGB / maximumRGB;
2485     }
2486
2487     return HSVValue(hue, saturation, value);
2488 }
2489
2490 wxImage::RGBValue wxImage::HSVtoRGB(const HSVValue& hsv)
2491 {
2492     double red, green, blue;
2493
2494     if ( wxIsNullDouble(hsv.saturation) )
2495     {
2496         // Grey
2497         red = hsv.value;
2498         green = hsv.value;
2499         blue = hsv.value;
2500     }
2501     else // not grey
2502     {
2503         double hue = hsv.hue * 6.0;      // sector 0 to 5
2504         int i = (int)floor(hue);
2505         double f = hue - i;          // fractional part of h
2506         double p = hsv.value * (1.0 - hsv.saturation);
2507
2508         switch (i)
2509         {
2510             case 0:
2511                 red = hsv.value;
2512                 green = hsv.value * (1.0 - hsv.saturation * (1.0 - f));
2513                 blue = p;
2514                 break;
2515
2516             case 1:
2517                 red = hsv.value * (1.0 - hsv.saturation * f);
2518                 green = hsv.value;
2519                 blue = p;
2520                 break;
2521
2522             case 2:
2523                 red = p;
2524                 green = hsv.value;
2525                 blue = hsv.value * (1.0 - hsv.saturation * (1.0 - f));
2526                 break;
2527
2528             case 3:
2529                 red = p;
2530                 green = hsv.value * (1.0 - hsv.saturation * f);
2531                 blue = hsv.value;
2532                 break;
2533
2534             case 4:
2535                 red = hsv.value * (1.0 - hsv.saturation * (1.0 - f));
2536                 green = p;
2537                 blue = hsv.value;
2538                 break;
2539
2540             default:    // case 5:
2541                 red = hsv.value;
2542                 green = p;
2543                 blue = hsv.value * (1.0 - hsv.saturation * f);
2544                 break;
2545         }
2546     }
2547
2548     return RGBValue((unsigned char)(red * 255.0),
2549                     (unsigned char)(green * 255.0),
2550                     (unsigned char)(blue * 255.0));
2551 }
2552
2553 /*
2554  * Rotates the hue of each pixel of the image. angle is a double in the range
2555  * -1.0..1.0 where -1.0 is -360 degrees and 1.0 is 360 degrees
2556  */
2557 void wxImage::RotateHue(double angle)
2558 {
2559     AllocExclusive();
2560
2561     unsigned char *srcBytePtr;
2562     unsigned char *dstBytePtr;
2563     unsigned long count;
2564     wxImage::HSVValue hsv;
2565     wxImage::RGBValue rgb;
2566
2567     wxASSERT (angle >= -1.0 && angle <= 1.0);
2568     count = M_IMGDATA->m_width * M_IMGDATA->m_height;
2569     if ( count > 0 && !wxIsNullDouble(angle) )
2570     {
2571         srcBytePtr = M_IMGDATA->m_data;
2572         dstBytePtr = srcBytePtr;
2573         do
2574         {
2575             rgb.red = *srcBytePtr++;
2576             rgb.green = *srcBytePtr++;
2577             rgb.blue = *srcBytePtr++;
2578             hsv = RGBtoHSV(rgb);
2579
2580             hsv.hue = hsv.hue + angle;
2581             if (hsv.hue > 1.0)
2582                 hsv.hue = hsv.hue - 1.0;
2583             else if (hsv.hue < 0.0)
2584                 hsv.hue = hsv.hue + 1.0;
2585
2586             rgb = HSVtoRGB(hsv);
2587             *dstBytePtr++ = rgb.red;
2588             *dstBytePtr++ = rgb.green;
2589             *dstBytePtr++ = rgb.blue;
2590         } while (--count != 0);
2591     }
2592 }
2593
2594 //-----------------------------------------------------------------------------
2595 // wxImageHandler
2596 //-----------------------------------------------------------------------------
2597
2598 IMPLEMENT_ABSTRACT_CLASS(wxImageHandler,wxObject)
2599
2600 #if wxUSE_STREAMS
2601 bool wxImageHandler::LoadFile( wxImage *WXUNUSED(image), wxInputStream& WXUNUSED(stream), bool WXUNUSED(verbose), int WXUNUSED(index) )
2602 {
2603     return false;
2604 }
2605
2606 bool wxImageHandler::SaveFile( wxImage *WXUNUSED(image), wxOutputStream& WXUNUSED(stream), bool WXUNUSED(verbose) )
2607 {
2608     return false;
2609 }
2610
2611 int wxImageHandler::GetImageCount( wxInputStream& WXUNUSED(stream) )
2612 {
2613     return 1;
2614 }
2615
2616 bool wxImageHandler::CanRead( const wxString& name )
2617 {
2618     if (wxFileExists(name))
2619     {
2620         wxImageFileInputStream stream(name);
2621         return CanRead(stream);
2622     }
2623
2624     wxLogError( _("Can't check image format of file '%s': file does not exist."), name.c_str() );
2625
2626     return false;
2627 }
2628
2629 bool wxImageHandler::CallDoCanRead(wxInputStream& stream)
2630 {
2631     wxFileOffset posOld = stream.TellI();
2632     if ( posOld == wxInvalidOffset )
2633     {
2634         // can't test unseekable stream
2635         return false;
2636     }
2637
2638     bool ok = DoCanRead(stream);
2639
2640     // restore the old position to be able to test other formats and so on
2641     if ( stream.SeekI(posOld) == wxInvalidOffset )
2642     {
2643         wxLogDebug(_T("Failed to rewind the stream in wxImageHandler!"));
2644
2645         // reading would fail anyhow as we're not at the right position
2646         return false;
2647     }
2648
2649     return ok;
2650 }
2651
2652 #endif // wxUSE_STREAMS
2653
2654 // ----------------------------------------------------------------------------
2655 // image histogram stuff
2656 // ----------------------------------------------------------------------------
2657
2658 bool
2659 wxImageHistogram::FindFirstUnusedColour(unsigned char *r,
2660                                         unsigned char *g,
2661                                         unsigned char *b,
2662                                         unsigned char r2,
2663                                         unsigned char b2,
2664                                         unsigned char g2) const
2665 {
2666     unsigned long key = MakeKey(r2, g2, b2);
2667
2668     while ( find(key) != end() )
2669     {
2670         // color already used
2671         r2++;
2672         if ( r2 >= 255 )
2673         {
2674             r2 = 0;
2675             g2++;
2676             if ( g2 >= 255 )
2677             {
2678                 g2 = 0;
2679                 b2++;
2680                 if ( b2 >= 255 )
2681                 {
2682                     wxLogError(_("No unused colour in image.") );
2683                     return false;
2684                 }
2685             }
2686         }
2687
2688         key = MakeKey(r2, g2, b2);
2689     }
2690
2691     if ( r )
2692         *r = r2;
2693     if ( g )
2694         *g = g2;
2695     if ( b )
2696         *b = b2;
2697
2698     return true;
2699 }
2700
2701 bool
2702 wxImage::FindFirstUnusedColour(unsigned char *r,
2703                                unsigned char *g,
2704                                unsigned char *b,
2705                                unsigned char r2,
2706                                unsigned char b2,
2707                                unsigned char g2) const
2708 {
2709     wxImageHistogram histogram;
2710
2711     ComputeHistogram(histogram);
2712
2713     return histogram.FindFirstUnusedColour(r, g, b, r2, g2, b2);
2714 }
2715
2716
2717
2718 // GRG, Dic/99
2719 // Counts and returns the number of different colours. Optionally stops
2720 // when it exceeds 'stopafter' different colours. This is useful, for
2721 // example, to see if the image can be saved as 8-bit (256 colour or
2722 // less, in this case it would be invoked as CountColours(256)). Default
2723 // value for stopafter is -1 (don't care).
2724 //
2725 unsigned long wxImage::CountColours( unsigned long stopafter ) const
2726 {
2727     wxHashTable h;
2728     wxObject dummy;
2729     unsigned char r, g, b;
2730     unsigned char *p;
2731     unsigned long size, nentries, key;
2732
2733     p = GetData();
2734     size = GetWidth() * GetHeight();
2735     nentries = 0;
2736
2737     for (unsigned long j = 0; (j < size) && (nentries <= stopafter) ; j++)
2738     {
2739         r = *(p++);
2740         g = *(p++);
2741         b = *(p++);
2742         key = wxImageHistogram::MakeKey(r, g, b);
2743
2744         if (h.Get(key) == NULL)
2745         {
2746             h.Put(key, &dummy);
2747             nentries++;
2748         }
2749     }
2750
2751     return nentries;
2752 }
2753
2754
2755 unsigned long wxImage::ComputeHistogram( wxImageHistogram &h ) const
2756 {
2757     unsigned char *p = GetData();
2758     unsigned long nentries = 0;
2759
2760     h.clear();
2761
2762     const unsigned long size = GetWidth() * GetHeight();
2763
2764     unsigned char r, g, b;
2765     for ( unsigned long n = 0; n < size; n++ )
2766     {
2767         r = *p++;
2768         g = *p++;
2769         b = *p++;
2770
2771         wxImageHistogramEntry& entry = h[wxImageHistogram::MakeKey(r, g, b)];
2772
2773         if ( entry.value++ == 0 )
2774             entry.index = nentries++;
2775     }
2776
2777     return nentries;
2778 }
2779
2780 /*
2781  * Rotation code by Carlos Moreno
2782  */
2783
2784 static const double wxROTATE_EPSILON = 1e-10;
2785
2786 // Auxiliary function to rotate a point (x,y) with respect to point p0
2787 // make it inline and use a straight return to facilitate optimization
2788 // also, the function receives the sine and cosine of the angle to avoid
2789 // repeating the time-consuming calls to these functions -- sin/cos can
2790 // be computed and stored in the calling function.
2791
2792 static inline wxRealPoint
2793 wxRotatePoint(const wxRealPoint& p, double cos_angle, double sin_angle,
2794               const wxRealPoint& p0)
2795 {
2796     return wxRealPoint(p0.x + (p.x - p0.x) * cos_angle - (p.y - p0.y) * sin_angle,
2797                        p0.y + (p.y - p0.y) * cos_angle + (p.x - p0.x) * sin_angle);
2798 }
2799
2800 static inline wxRealPoint
2801 wxRotatePoint(double x, double y, double cos_angle, double sin_angle,
2802               const wxRealPoint & p0)
2803 {
2804     return wxRotatePoint (wxRealPoint(x,y), cos_angle, sin_angle, p0);
2805 }
2806
2807 wxImage wxImage::Rotate(double angle, const wxPoint & centre_of_rotation, bool interpolating, wxPoint * offset_after_rotation) const
2808 {
2809     int i;
2810     angle = -angle;     // screen coordinates are a mirror image of "real" coordinates
2811
2812     bool has_alpha = HasAlpha();
2813
2814     // Create pointer-based array to accelerate access to wxImage's data
2815     unsigned char ** data = new unsigned char * [GetHeight()];
2816     data[0] = GetData();
2817     for (i = 1; i < GetHeight(); i++)
2818         data[i] = data[i - 1] + (3 * GetWidth());
2819
2820     // Same for alpha channel
2821     unsigned char ** alpha = NULL;
2822     if (has_alpha)
2823     {
2824         alpha = new unsigned char * [GetHeight()];
2825         alpha[0] = GetAlpha();
2826         for (i = 1; i < GetHeight(); i++)
2827             alpha[i] = alpha[i - 1] + GetWidth();
2828     }
2829
2830     // precompute coefficients for rotation formula
2831     // (sine and cosine of the angle)
2832     const double cos_angle = cos(angle);
2833     const double sin_angle = sin(angle);
2834
2835     // Create new Image to store the result
2836     // First, find rectangle that covers the rotated image;  to do that,
2837     // rotate the four corners
2838
2839     const wxRealPoint p0(centre_of_rotation.x, centre_of_rotation.y);
2840
2841     wxRealPoint p1 = wxRotatePoint (0, 0, cos_angle, sin_angle, p0);
2842     wxRealPoint p2 = wxRotatePoint (0, GetHeight(), cos_angle, sin_angle, p0);
2843     wxRealPoint p3 = wxRotatePoint (GetWidth(), 0, cos_angle, sin_angle, p0);
2844     wxRealPoint p4 = wxRotatePoint (GetWidth(), GetHeight(), cos_angle, sin_angle, p0);
2845
2846     int x1a = (int) floor (wxMin (wxMin(p1.x, p2.x), wxMin(p3.x, p4.x)));
2847     int y1a = (int) floor (wxMin (wxMin(p1.y, p2.y), wxMin(p3.y, p4.y)));
2848     int x2a = (int) ceil (wxMax (wxMax(p1.x, p2.x), wxMax(p3.x, p4.x)));
2849     int y2a = (int) ceil (wxMax (wxMax(p1.y, p2.y), wxMax(p3.y, p4.y)));
2850
2851     // Create rotated image
2852     wxImage rotated (x2a - x1a + 1, y2a - y1a + 1, false);
2853     // With alpha channel
2854     if (has_alpha)
2855         rotated.SetAlpha();
2856
2857     if (offset_after_rotation != NULL)
2858     {
2859         *offset_after_rotation = wxPoint (x1a, y1a);
2860     }
2861
2862     // GRG: The rotated (destination) image is always accessed
2863     //      sequentially, so there is no need for a pointer-based
2864     //      array here (and in fact it would be slower).
2865     //
2866     unsigned char * dst = rotated.GetData();
2867
2868     unsigned char * alpha_dst = NULL;
2869     if (has_alpha)
2870         alpha_dst = rotated.GetAlpha();
2871
2872     // GRG: if the original image has a mask, use its RGB values
2873     //      as the blank pixel, else, fall back to default (black).
2874     //
2875     unsigned char blank_r = 0;
2876     unsigned char blank_g = 0;
2877     unsigned char blank_b = 0;
2878
2879     if (HasMask())
2880     {
2881         blank_r = GetMaskRed();
2882         blank_g = GetMaskGreen();
2883         blank_b = GetMaskBlue();
2884         rotated.SetMaskColour( blank_r, blank_g, blank_b );
2885     }
2886
2887     // Now, for each point of the rotated image, find where it came from, by
2888     // performing an inverse rotation (a rotation of -angle) and getting the
2889     // pixel at those coordinates
2890
2891     // GRG: I've taken the (interpolating) test out of the loops, so that
2892     //      it is done only once, instead of repeating it for each pixel.
2893
2894     int x;
2895     if (interpolating)
2896     {
2897         for (int y = 0; y < rotated.GetHeight(); y++)
2898         {
2899             for (x = 0; x < rotated.GetWidth(); x++)
2900             {
2901                 wxRealPoint src = wxRotatePoint (x + x1a, y + y1a, cos_angle, -sin_angle, p0);
2902
2903                 if (-0.25 < src.x && src.x < GetWidth() - 0.75 &&
2904                     -0.25 < src.y && src.y < GetHeight() - 0.75)
2905                 {
2906                     // interpolate using the 4 enclosing grid-points.  Those
2907                     // points can be obtained using floor and ceiling of the
2908                     // exact coordinates of the point
2909                     int x1, y1, x2, y2;
2910
2911                     if (0 < src.x && src.x < GetWidth() - 1)
2912                     {
2913                         x1 = wxRound(floor(src.x));
2914                         x2 = wxRound(ceil(src.x));
2915                     }
2916                     else    // else means that x is near one of the borders (0 or width-1)
2917                     {
2918                         x1 = x2 = wxRound (src.x);
2919                     }
2920
2921                     if (0 < src.y && src.y < GetHeight() - 1)
2922                     {
2923                         y1 = wxRound(floor(src.y));
2924                         y2 = wxRound(ceil(src.y));
2925                     }
2926                     else
2927                     {
2928                         y1 = y2 = wxRound (src.y);
2929                     }
2930
2931                     // get four points and the distances (square of the distance,
2932                     // for efficiency reasons) for the interpolation formula
2933
2934                     // GRG: Do not calculate the points until they are
2935                     //      really needed -- this way we can calculate
2936                     //      just one, instead of four, if d1, d2, d3
2937                     //      or d4 are < wxROTATE_EPSILON
2938
2939                     const double d1 = (src.x - x1) * (src.x - x1) + (src.y - y1) * (src.y - y1);
2940                     const double d2 = (src.x - x2) * (src.x - x2) + (src.y - y1) * (src.y - y1);
2941                     const double d3 = (src.x - x2) * (src.x - x2) + (src.y - y2) * (src.y - y2);
2942                     const double d4 = (src.x - x1) * (src.x - x1) + (src.y - y2) * (src.y - y2);
2943
2944                     // Now interpolate as a weighted average of the four surrounding
2945                     // points, where the weights are the distances to each of those points
2946
2947                     // If the point is exactly at one point of the grid of the source
2948                     // image, then don't interpolate -- just assign the pixel
2949
2950                     // d1,d2,d3,d4 are positive -- no need for abs()
2951                     if (d1 < wxROTATE_EPSILON)
2952                     {
2953                         unsigned char *p = data[y1] + (3 * x1);
2954                         *(dst++) = *(p++);
2955                         *(dst++) = *(p++);
2956                         *(dst++) = *p;
2957
2958                         if (has_alpha)
2959                             *(alpha_dst++) = *(alpha[y1] + x1);
2960                     }
2961                     else if (d2 < wxROTATE_EPSILON)
2962                     {
2963                         unsigned char *p = data[y1] + (3 * x2);
2964                         *(dst++) = *(p++);
2965                         *(dst++) = *(p++);
2966                         *(dst++) = *p;
2967
2968                         if (has_alpha)
2969                             *(alpha_dst++) = *(alpha[y1] + x2);
2970                     }
2971                     else if (d3 < wxROTATE_EPSILON)
2972                     {
2973                         unsigned char *p = data[y2] + (3 * x2);
2974                         *(dst++) = *(p++);
2975                         *(dst++) = *(p++);
2976                         *(dst++) = *p;
2977
2978                         if (has_alpha)
2979                             *(alpha_dst++) = *(alpha[y2] + x2);
2980                     }
2981                     else if (d4 < wxROTATE_EPSILON)
2982                     {
2983                         unsigned char *p = data[y2] + (3 * x1);
2984                         *(dst++) = *(p++);
2985                         *(dst++) = *(p++);
2986                         *(dst++) = *p;
2987
2988                         if (has_alpha)
2989                             *(alpha_dst++) = *(alpha[y2] + x1);
2990                     }
2991                     else
2992                     {
2993                         // weights for the weighted average are proportional to the inverse of the distance
2994                         unsigned char *v1 = data[y1] + (3 * x1);
2995                         unsigned char *v2 = data[y1] + (3 * x2);
2996                         unsigned char *v3 = data[y2] + (3 * x2);
2997                         unsigned char *v4 = data[y2] + (3 * x1);
2998
2999                         const double w1 = 1/d1, w2 = 1/d2, w3 = 1/d3, w4 = 1/d4;
3000
3001                         // GRG: Unrolled.
3002
3003                         *(dst++) = (unsigned char)
3004                             ( (w1 * *(v1++) + w2 * *(v2++) +
3005                                w3 * *(v3++) + w4 * *(v4++)) /
3006                               (w1 + w2 + w3 + w4) );
3007                         *(dst++) = (unsigned char)
3008                             ( (w1 * *(v1++) + w2 * *(v2++) +
3009                                w3 * *(v3++) + w4 * *(v4++)) /
3010                               (w1 + w2 + w3 + w4) );
3011                         *(dst++) = (unsigned char)
3012                             ( (w1 * *v1 + w2 * *v2 +
3013                                w3 * *v3 + w4 * *v4) /
3014                               (w1 + w2 + w3 + w4) );
3015
3016                         if (has_alpha)
3017                         {
3018                             v1 = alpha[y1] + (x1);
3019                             v2 = alpha[y1] + (x2);
3020                             v3 = alpha[y2] + (x2);
3021                             v4 = alpha[y2] + (x1);
3022
3023                             *(alpha_dst++) = (unsigned char)
3024                                 ( (w1 * *v1 + w2 * *v2 +
3025                                    w3 * *v3 + w4 * *v4) /
3026                                   (w1 + w2 + w3 + w4) );
3027                         }
3028                     }
3029                 }
3030                 else
3031                 {
3032                     *(dst++) = blank_r;
3033                     *(dst++) = blank_g;
3034                     *(dst++) = blank_b;
3035
3036                     if (has_alpha)
3037                         *(alpha_dst++) = 0;
3038                 }
3039             }
3040         }
3041     }
3042     else    // not interpolating
3043     {
3044         for (int y = 0; y < rotated.GetHeight(); y++)
3045         {
3046             for (x = 0; x < rotated.GetWidth(); x++)
3047             {
3048                 wxRealPoint src = wxRotatePoint (x + x1a, y + y1a, cos_angle, -sin_angle, p0);
3049
3050                 const int xs = wxRound (src.x);      // wxRound rounds to the
3051                 const int ys = wxRound (src.y);      // closest integer
3052
3053                 if (0 <= xs && xs < GetWidth() &&
3054                     0 <= ys && ys < GetHeight())
3055                 {
3056                     unsigned char *p = data[ys] + (3 * xs);
3057                     *(dst++) = *(p++);
3058                     *(dst++) = *(p++);
3059                     *(dst++) = *p;
3060
3061                     if (has_alpha)
3062                         *(alpha_dst++) = *(alpha[ys] + (xs));
3063                 }
3064                 else
3065                 {
3066                     *(dst++) = blank_r;
3067                     *(dst++) = blank_g;
3068                     *(dst++) = blank_b;
3069
3070                     if (has_alpha)
3071                         *(alpha_dst++) = 255;
3072                 }
3073             }
3074         }
3075     }
3076
3077     delete [] data;
3078
3079     if (has_alpha)
3080         delete [] alpha;
3081
3082     return rotated;
3083 }
3084
3085
3086
3087
3088
3089 // A module to allow wxImage initialization/cleanup
3090 // without calling these functions from app.cpp or from
3091 // the user's application.
3092
3093 class wxImageModule: public wxModule
3094 {
3095 DECLARE_DYNAMIC_CLASS(wxImageModule)
3096 public:
3097     wxImageModule() {}
3098     bool OnInit() { wxImage::InitStandardHandlers(); return true; };
3099     void OnExit() { wxImage::CleanUpHandlers(); };
3100 };
3101
3102 IMPLEMENT_DYNAMIC_CLASS(wxImageModule, wxModule)
3103
3104
3105 #endif // wxUSE_IMAGE