X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/45647dcf1059cc6515a0c6157f7c077cfc2abd31..68698f0308f5c46966b7de12b34f68ec23dd3ec8:/src/common/image.cpp

diff --git a/src/common/image.cpp b/src/common/image.cpp
index 9d5716221c..aa19e4ea35 100644
--- a/src/common/image.cpp
+++ b/src/common/image.cpp
@@ -31,6 +31,7 @@
 #include "wx/wfstream.h"
 #include "wx/intl.h"
 #include "wx/module.h"
+#include "wx/hash.h"
 
 // For memcpy
 #include <string.h>
@@ -49,39 +50,53 @@ class wxImageRefData: public wxObjectRefData
 {
 public:
     wxImageRefData();
-    ~wxImageRefData();
+    virtual ~wxImageRefData();
 
     int             m_width;
     int             m_height;
     unsigned char  *m_data;
+
     bool            m_hasMask;
     unsigned char   m_maskRed,m_maskGreen,m_maskBlue;
+
+    // alpha channel data, may be NULL for the formats without alpha support
+    unsigned char  *m_alpha;
+
     bool            m_ok;
     bool            m_static;
+
 #if wxUSE_PALETTE
     wxPalette       m_palette;
 #endif // wxUSE_PALETTE
+
     wxArrayString   m_optionNames;
     wxArrayString   m_optionValues;
+
+    DECLARE_NO_COPY_CLASS(wxImageRefData)
 };
 
 wxImageRefData::wxImageRefData()
 {
     m_width = 0;
     m_height = 0;
-    m_data = (unsigned char*) NULL;
-    m_ok = FALSE;
+    m_data =
+    m_alpha = (unsigned char *) NULL;
+
     m_maskRed = 0;
     m_maskGreen = 0;
     m_maskBlue = 0;
     m_hasMask = FALSE;
+
+    m_ok = FALSE;
     m_static = FALSE;
 }
 
 wxImageRefData::~wxImageRefData()
 {
-    if (m_data && !m_static)
+    if ( !m_static )
         free( m_data );
+
+    free(m_alpha);
 }
 
 wxList wxImage::sm_handlers;
@@ -131,6 +146,7 @@ wxImage::wxImage( wxInputStream& stream, const wxString& mimetype, int index )
 #endif // wxUSE_STREAMS
 
 wxImage::wxImage( const wxImage& image )
+    : wxObject()
 {
     Ref(image);
 }
@@ -194,14 +210,113 @@ wxImage wxImage::Copy() const
 
     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height );
 
+    unsigned char *data = image.GetData();
+
+    wxCHECK_MSG( data, image, wxT("unable to create image") );
+
+    image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
+    image.SetMask( M_IMGDATA->m_hasMask );
+
+    memcpy( data, GetData(), M_IMGDATA->m_width*M_IMGDATA->m_height*3 );
+
+    return image;
+}
+
+wxImage wxImage::ShrinkBy( int xFactor , int yFactor ) const
+{
+    if( xFactor == 1 && yFactor == 1 )
+        return Copy() ;
+        
+    wxImage image;
+
+    wxCHECK_MSG( Ok(), image, wxT("invalid image") );
+
+    // can't scale to/from 0 size
+    wxCHECK_MSG( (xFactor > 0) && (yFactor > 0), image,
+                 wxT("invalid new image size") );
+
+    long old_height = M_IMGDATA->m_height,
+         old_width  = M_IMGDATA->m_width;
+         
+    wxCHECK_MSG( (old_height > 0) && (old_width > 0), image,
+                 wxT("invalid old image size") );
+
+    long width = old_width / xFactor ;
+    long height = old_height / yFactor ;
+
+    image.Create( width , height );
+
     char unsigned *data = image.GetData();
 
     wxCHECK_MSG( data, image, wxT("unable to create image") );
 
+    bool hasMask = false ;
+    unsigned char maskRed = 0;
+    unsigned char maskGreen = 0;
+    unsigned char maskBlue =0 ;
     if (M_IMGDATA->m_hasMask)
-        image.SetMaskColour( M_IMGDATA->m_maskRed, M_IMGDATA->m_maskGreen, M_IMGDATA->m_maskBlue );
+    {
+        hasMask = true ;
+        maskRed = M_IMGDATA->m_maskRed;
+        maskGreen = M_IMGDATA->m_maskGreen;
+        maskBlue =M_IMGDATA->m_maskBlue ;
+      
+        image.SetMaskColour( M_IMGDATA->m_maskRed,
+                             M_IMGDATA->m_maskGreen,
+                             M_IMGDATA->m_maskBlue );
+    }
+    char unsigned *source_data = M_IMGDATA->m_data;
+    char unsigned *target_data = data;
+    
+    for (long y = 0; y < height; y++)
+    {
+        for (long x = 0; x < width; x++)
+        {
+            unsigned long avgRed = 0 ;
+            unsigned long avgGreen = 0;
+            unsigned long avgBlue = 0;
+            unsigned long counter = 0 ;
+            // determine average
+            for ( int y1 = 0 ; y1 < yFactor ; ++y1 )
+            {
+                long y_offset = (y * yFactor + y1) * old_width;
+                for ( int x1 = 0 ; x1 < xFactor ; ++x1 )
+                {
+                    unsigned char *pixel = source_data + 3 * ( y_offset + x * xFactor + x1 ) ;
+                    unsigned char red = pixel[0] ;
+                    unsigned char green = pixel[1] ;
+                    unsigned char blue = pixel[2] ;
+                    if ( !hasMask || red != maskRed || green != maskGreen || blue != maskBlue )
+                    {
+                        avgRed += red ;
+                        avgGreen += green ;
+                        avgBlue += blue ;
+                        counter++ ;
+                    }
+                }
+            }
+            if ( counter == 0 )
+            {
+                *(target_data++) = M_IMGDATA->m_maskRed ;
+                *(target_data++) = M_IMGDATA->m_maskGreen ;
+                *(target_data++) = M_IMGDATA->m_maskBlue ;
+            }
+            else
+            {
+                *(target_data++) = avgRed / counter ;
+                *(target_data++) = avgGreen / counter ;
+                *(target_data++) = avgBlue / counter ;
+            }
+        }
+    }
 
-    memcpy( data, GetData(), M_IMGDATA->m_width*M_IMGDATA->m_height*3 );
+    // In case this is a cursor, make sure the hotspot is scalled accordingly:
+    if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X) )
+        image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X,
+                (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X))/xFactor);
+    if ( HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y) )
+        image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y,
+                (GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y))/yFactor);
 
     return image;
 }
@@ -221,9 +336,14 @@ wxImage wxImage::Scale( int width, int height ) const
     wxCHECK_MSG( (old_height > 0) && (old_width > 0), image,
                  wxT("invalid old image size") );
 
+    if ( old_width % width == 0 && old_width >= width &&
+        old_height % height == 0 && old_height >= height )
+    {
+        return ShrinkBy( old_width / width , old_height / height ) ;
+    }
     image.Create( width, height );
 
-    char unsigned *data = image.GetData();
+    unsigned char *data = image.GetData();
 
     wxCHECK_MSG( data, image, wxT("unable to create image") );
 
@@ -234,8 +354,8 @@ wxImage wxImage::Scale( int width, int height ) const
                              M_IMGDATA->m_maskBlue );
     }
 
-    char unsigned *source_data = M_IMGDATA->m_data;
-    char unsigned *target_data = data;
+    unsigned char *source_data = M_IMGDATA->m_data;
+    unsigned char *target_data = data;
 
 #if 0
     // This is nonsense, RR.
@@ -294,7 +414,7 @@ wxImage wxImage::Rotate90( bool clockwise ) const
 
     image.Create( M_IMGDATA->m_height, M_IMGDATA->m_width );
 
-    char unsigned *data = image.GetData();
+    unsigned char *data = image.GetData();
 
     wxCHECK_MSG( data, image, wxT("unable to create image") );
 
@@ -304,8 +424,8 @@ wxImage wxImage::Rotate90( bool clockwise ) const
     long height = M_IMGDATA->m_height;
     long width  = M_IMGDATA->m_width;
 
-    char unsigned *source_data = M_IMGDATA->m_data;
-    char unsigned *target_data;
+    unsigned char *source_data = M_IMGDATA->m_data;
+    unsigned char *target_data;
 
     for (long j = 0; j < height; j++)
     {
@@ -331,7 +451,7 @@ wxImage wxImage::Mirror( bool horizontally ) const
 
     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height );
 
-    char unsigned *data = image.GetData();
+    unsigned char *data = image.GetData();
 
     wxCHECK_MSG( data, image, wxT("unable to create image") );
 
@@ -341,8 +461,8 @@ wxImage wxImage::Mirror( bool horizontally ) const
     long height = M_IMGDATA->m_height;
     long width  = M_IMGDATA->m_width;
 
-    char unsigned *source_data = M_IMGDATA->m_data;
-    char unsigned *target_data;
+    unsigned char *source_data = M_IMGDATA->m_data;
+    unsigned char *target_data;
 
     if (horizontally)
     {
@@ -385,7 +505,7 @@ wxImage wxImage::GetSubImage( const wxRect &rect ) const
 
     image.Create( subwidth, subheight );
 
-    char unsigned *subdata = image.GetData(), *data=GetData();
+    unsigned char *subdata = image.GetData(), *data=GetData();
 
     wxCHECK_MSG( subdata, image, wxT("unable to create image") );
 
@@ -493,7 +613,7 @@ void wxImage::Replace( unsigned char r1, unsigned char g1, unsigned char b1,
 {
     wxCHECK_RET( Ok(), wxT("invalid image") );
 
-    char unsigned *data = GetData();
+    unsigned char *data = GetData();
 
     const int w = GetWidth();
     const int h = GetHeight();
@@ -519,7 +639,7 @@ wxImage wxImage::ConvertToMono( unsigned char r, unsigned char g, unsigned char
 
     image.Create( M_IMGDATA->m_width, M_IMGDATA->m_height );
 
-    char unsigned *data = image.GetData();
+    unsigned char *data = image.GetData();
 
     wxCHECK_MSG( data, image, wxT("unable to create image") );
 
@@ -534,8 +654,8 @@ wxImage wxImage::ConvertToMono( unsigned char r, unsigned char g, unsigned char
 
     long size = M_IMGDATA->m_height * M_IMGDATA->m_width;
 
-    char unsigned *srcd = M_IMGDATA->m_data;
-    char unsigned *tard = image.GetData();
+    unsigned char *srcd = M_IMGDATA->m_data;
+    unsigned char *tard = image.GetData();
 
     for ( long i = 0; i < size; i++, srcd += 3, tard += 3 )
     {
@@ -614,14 +734,14 @@ bool wxImage::Ok() const
     return data && data->m_ok && data->m_width && data->m_height;
 }
 
-char unsigned *wxImage::GetData() const
+unsigned char *wxImage::GetData() const
 {
-    wxCHECK_MSG( Ok(), (char unsigned *)NULL, wxT("invalid image") );
+    wxCHECK_MSG( Ok(), (unsigned char *)NULL, wxT("invalid image") );
 
     return M_IMGDATA->m_data;
 }
 
-void wxImage::SetData( char unsigned *data )
+void wxImage::SetData( unsigned char *data )
 {
     wxCHECK_RET( Ok(), wxT("invalid image") );
 
@@ -641,7 +761,7 @@ void wxImage::SetData( char unsigned *data )
     m_refData = newRefData;
 }
 
-void wxImage::SetData( char unsigned *data, int new_width, int new_height )
+void wxImage::SetData( unsigned char *data, int new_width, int new_height )
 {
     wxImageRefData *newRefData = new wxImageRefData();
 
@@ -669,6 +789,59 @@ void wxImage::SetData( char unsigned *data, int new_width, int new_height )
     m_refData = newRefData;
 }
 
+// ----------------------------------------------------------------------------
+// alpha channel support
+// ----------------------------------------------------------------------------
+
+void wxImage::SetAlpha(int x, int y, unsigned char alpha)
+{
+    wxCHECK_RET( Ok() && HasAlpha(), wxT("invalid image or no alpha channel") );
+
+    int w = M_IMGDATA->m_width,
+        h = M_IMGDATA->m_height;
+
+    wxCHECK_RET( x >=0 && y >= 0 && x < w && y < h, wxT("invalid image index") );
+
+    M_IMGDATA->m_alpha[y*w + x] = alpha;
+}
+
+unsigned char wxImage::GetAlpha(int x, int y)
+{
+    wxCHECK_MSG( Ok() && HasAlpha(), 0, wxT("invalid image or no alpha channel") );
+
+    int w = M_IMGDATA->m_width,
+        h = M_IMGDATA->m_height;
+
+    wxCHECK_MSG( x >=0 && y >= 0 && x < w && y < h, 0, wxT("invalid image index") );
+
+    return M_IMGDATA->m_alpha[y*w + x];
+}
+
+void wxImage::SetAlpha( unsigned char *alpha )
+{
+    wxCHECK_RET( Ok(), wxT("invalid image") );
+
+    if ( !alpha )
+    {
+        alpha = (unsigned char *)
+                    malloc(M_IMGDATA->m_width*M_IMGDATA->m_height*3);
+    }
+
+    delete [] M_IMGDATA->m_alpha;
+    M_IMGDATA->m_alpha = alpha;
+}
+
+unsigned char *wxImage::GetAlpha() const
+{
+    wxCHECK_MSG( Ok(), (unsigned char *)NULL, wxT("invalid image") );
+
+    return M_IMGDATA->m_alpha;
+}
+
+// ----------------------------------------------------------------------------
+// mask support
+// ----------------------------------------------------------------------------
+
 void wxImage::SetMaskColour( unsigned char r, unsigned char g, unsigned char b )
 {
     wxCHECK_RET( Ok(), wxT("invalid image") );
@@ -728,73 +901,26 @@ int wxImage::GetHeight() const
     return M_IMGDATA->m_height;
 }
 
-
-bool wxImage::FindFirstUnusedColour(
-            unsigned char *r, unsigned char *g, unsigned char *b,
-            unsigned char startR, unsigned char startG, unsigned char startB) const
-{
-    wxImageHistogram histogram;
-    unsigned long key;
-   
-    ComputeHistogram(histogram);
-    
-    unsigned char r2 = startR;
-    unsigned char g2 = startG;
-    unsigned char b2 = startB;
-    
-    key = (r2 << 16) | (g2 << 8) | b2;
-
-    while ( histogram.find(key) != histogram.end() )
-    {
-        // color already used
-        r2++;
-        if ( r2 >= 255 )
-        {
-            r2 = 0;
-            g2++;
-            if ( g2 >= 255 )
-            {
-                g2 = 0;
-                b2++;
-                if ( b2 >= 255 )
-                {
-                    wxLogError( _("GetUnusedColour:: No Unused Color in image ") );            
-                    return FALSE;                              
-                }
-            }
-        }
-        
-        key = (r2 << 16) | (g2 << 8) | b2;
-    }
-    
-    if (r) *r = r2;
-    if (g) *g = g2;
-    if (b) *b = b2;
-    
-    return TRUE;
-}
-
-
-bool wxImage::SetMaskFromImage(const wxImage& mask, 
+bool wxImage::SetMaskFromImage(const wxImage& mask,
                                unsigned char mr, unsigned char mg, unsigned char mb)
 {
     // check that the images are the same size
     if ( (M_IMGDATA->m_height != mask.GetHeight() ) || (M_IMGDATA->m_width != mask.GetWidth () ) )
     {
-        wxLogError( _("Image and Mask have different sizes") );            
+        wxLogError( _("Image and Mask have different sizes") );
         return FALSE;
     }
-    
+
     // find unused colour
     unsigned char r,g,b ;
     if (!FindFirstUnusedColour(&r, &g, &b))
     {
-        wxLogError( _("No Unused Color in image being masked") );            
+        wxLogError( _("No Unused Color in image being masked") );
         return FALSE ;
     }
-        
-    char unsigned *imgdata = GetData();
-    char unsigned *maskdata = mask.GetData();
+
+    unsigned char *imgdata = GetData();
+    unsigned char *maskdata = mask.GetData();
 
     const int w = GetWidth();
     const int h = GetHeight();
@@ -816,7 +942,7 @@ bool wxImage::SetMaskFromImage(const wxImage& mask,
 
     SetMaskColour(r, g, b);
     SetMask(TRUE);
-    
+
     return TRUE;
 }
 
@@ -943,7 +1069,7 @@ bool wxImage::LoadFile( const wxString& filename, const wxString& mimetype, int
 bool wxImage::SaveFile( const wxString& filename ) const
 {
     wxString ext = filename.AfterLast('.').Lower();
-    
+
     wxImageHandler * pHandler = FindHandler(ext, -1);
     if (pHandler)
     {
@@ -963,7 +1089,7 @@ bool wxImage::SaveFile( const wxString& filename, int type ) const
 
     wxFileOutputStream stream(filename);
 
-    if ( stream.LastError() == wxStream_NOERROR )
+    if ( stream.IsOk() )
     {
         wxBufferedOutputStream bstream( stream );
         return SaveFile(bstream, type);
@@ -980,7 +1106,7 @@ bool wxImage::SaveFile( const wxString& filename, const wxString& mimetype ) con
 
     wxFileOutputStream stream(filename);
 
-    if ( stream.LastError() == wxStream_NOERROR )
+    if ( stream.IsOk() )
     {
         wxBufferedOutputStream bstream( stream );
         return SaveFile(bstream, mimetype);
@@ -1004,17 +1130,18 @@ int wxImage::GetImageCount( const wxString &name, long type )
 {
 #if wxUSE_STREAMS
   wxFileInputStream stream(name);
-  return GetImageCount(stream, type);
-#else
-  return 0;
+  if (stream.Ok())
+      return GetImageCount(stream, type);
 #endif
+
+  return 0;
 }
 
 #if wxUSE_STREAMS
 
 bool wxImage::CanRead( wxInputStream &stream )
 {
-    wxList &list=GetHandlers();
+    const wxList& list = GetHandlers();
 
     for ( wxList::Node *node = list.GetFirst(); node; node = node->GetNext() )
     {
@@ -1091,7 +1218,7 @@ bool wxImage::LoadFile( wxInputStream& stream, long type, int index )
 
     handler = FindHandler(type);
 
-    if (handler == NULL)
+    if (handler == 0)
     {
         wxLogWarning( _("No image handler for type %d defined."), type );
 
@@ -1109,7 +1236,7 @@ bool wxImage::LoadFile( wxInputStream& stream, const wxString& mimetype, int ind
 
     wxImageHandler *handler = FindHandlerMime(mimetype);
 
-    if (handler == NULL)
+    if (handler == 0)
     {
         wxLogWarning( _("No image handler for type %s defined."), mimetype.GetData() );
 
@@ -1125,7 +1252,7 @@ bool wxImage::SaveFile( wxOutputStream& stream, int type ) const
 
     wxImageHandler *handler = FindHandler(type);
 
-    if (handler == NULL)
+    if (handler == 0)
     {
         wxLogWarning( _("No image handler for type %d defined."), type );
 
@@ -1141,7 +1268,7 @@ bool wxImage::SaveFile( wxOutputStream& stream, const wxString& mimetype ) const
 
     wxImageHandler *handler = FindHandlerMime(mimetype);
 
-    if (handler == NULL)
+    if (handler == 0)
     {
         wxLogWarning( _("No image handler for type %s defined."), mimetype.GetData() );
 
@@ -1157,7 +1284,23 @@ void wxImage::AddHandler( wxImageHandler *handler )
     // make sure that the memory will be freed at the program end
     sm_handlers.DeleteContents(TRUE);
 
-    sm_handlers.Append( handler );
+    // Check for an existing handler of the type being added.
+    if (FindHandler( handler->GetType() ) == 0)
+    {
+        sm_handlers.Append( handler );
+    }
+    else
+    {
+        // This is not documented behaviour, merely the simplest 'fix'
+        // for preventing duplicate additions.  If someone ever has
+        // a good reason to add and remove duplicate handlers (and they
+        // may) we should probably refcount the duplicates.
+        //   also an issue in InsertHandler below.
+
+        wxLogDebug( _T("Adding duplicate image handler for '%s'"),
+                    handler->GetName().c_str() );
+        delete handler;
+    }
 }
 
 void wxImage::InsertHandler( wxImageHandler *handler )
@@ -1165,7 +1308,18 @@ void wxImage::InsertHandler( wxImageHandler *handler )
     // make sure that the memory will be freed at the program end
     sm_handlers.DeleteContents(TRUE);
 
-    sm_handlers.Insert( handler );
+    // Check for an existing handler of the type being added.
+    if (FindHandler( handler->GetType() ) == 0)
+    {
+        sm_handlers.Insert( handler );
+    }
+    else
+    {
+        // see AddHandler for additional comments.
+        wxLogDebug( _T("Inserting duplicate image handler for '%s'"),
+                    handler->GetName().c_str() );
+        delete handler;
+    }
 }
 
 bool wxImage::RemoveHandler( const wxString& name )
@@ -1182,53 +1336,53 @@ bool wxImage::RemoveHandler( const wxString& name )
 
 wxImageHandler *wxImage::FindHandler( const wxString& name )
 {
-    wxNode *node = sm_handlers.First();
+    wxNode *node = sm_handlers.GetFirst();
     while (node)
     {
-        wxImageHandler *handler = (wxImageHandler*)node->Data();
+        wxImageHandler *handler = (wxImageHandler*)node->GetData();
         if (handler->GetName().Cmp(name) == 0) return handler;
 
-        node = node->Next();
+        node = node->GetNext();
     }
-    return (wxImageHandler *)NULL;
+    return 0;
 }
 
 wxImageHandler *wxImage::FindHandler( const wxString& extension, long bitmapType )
 {
-    wxNode *node = sm_handlers.First();
+    wxNode *node = sm_handlers.GetFirst();
     while (node)
     {
-        wxImageHandler *handler = (wxImageHandler*)node->Data();
+        wxImageHandler *handler = (wxImageHandler*)node->GetData();
         if ( (handler->GetExtension().Cmp(extension) == 0) &&
             (bitmapType == -1 || handler->GetType() == bitmapType) )
             return handler;
-        node = node->Next();
+        node = node->GetNext();
     }
-    return (wxImageHandler*)NULL;
+    return 0;
 }
 
 wxImageHandler *wxImage::FindHandler( long bitmapType )
 {
-    wxNode *node = sm_handlers.First();
+    wxNode *node = sm_handlers.GetFirst();
     while (node)
     {
-        wxImageHandler *handler = (wxImageHandler *)node->Data();
+        wxImageHandler *handler = (wxImageHandler *)node->GetData();
         if (handler->GetType() == bitmapType) return handler;
-        node = node->Next();
+        node = node->GetNext();
     }
-    return NULL;
+    return 0;
 }
 
 wxImageHandler *wxImage::FindHandlerMime( const wxString& mimetype )
 {
-    wxNode *node = sm_handlers.First();
+    wxNode *node = sm_handlers.GetFirst();
     while (node)
     {
-        wxImageHandler *handler = (wxImageHandler *)node->Data();
+        wxImageHandler *handler = (wxImageHandler *)node->GetData();
         if (handler->GetMimeType().IsSameAs(mimetype, FALSE)) return handler;
-        node = node->Next();
+        node = node->GetNext();
     }
-    return NULL;
+    return 0;
 }
 
 void wxImage::InitStandardHandlers()
@@ -1236,19 +1390,15 @@ void wxImage::InitStandardHandlers()
 #if wxUSE_STREAMS
     AddHandler(new wxBMPHandler);
 #endif // wxUSE_STREAMS
-
-#if wxUSE_XPM && !defined(__WXGTK__) && !defined(__WXMOTIF__)
-    AddHandler(new wxXPMHandler);
-#endif
 }
 
 void wxImage::CleanUpHandlers()
 {
-    wxNode *node = sm_handlers.First();
+    wxNode *node = sm_handlers.GetFirst();
     while (node)
     {
-        wxImageHandler *handler = (wxImageHandler *)node->Data();
-        wxNode *next = node->Next();
+        wxImageHandler *handler = (wxImageHandler *)node->GetData();
+        wxNode *next = node->GetNext();
         delete handler;
         delete node;
         node = next;
@@ -1285,12 +1435,32 @@ bool wxImageHandler::CanRead( const wxString& name )
         return CanRead(stream);
     }
 
-    else {
-        wxLogError( _("Can't check image format of file '%s': file does not exist."), name.c_str() );
+    wxLogError( _("Can't check image format of file '%s': file does not exist."), name.c_str() );
+
+    return FALSE;
+}
+
+bool wxImageHandler::CallDoCanRead(wxInputStream& stream)
+{
+    off_t posOld = stream.TellI();
+    if ( posOld == wxInvalidOffset )
+    {
+        // can't test unseekable stream
+        return FALSE;
+    }
+
+    bool ok = DoCanRead(stream);
 
+    // restore the old position to be able to test other formats and so on
+    if ( stream.SeekI(posOld) == wxInvalidOffset )
+    {
+        wxLogDebug(_T("Failed to rewind the stream in wxImageHandler!"));
+
+        // reading would fail anyhow as we're not at the right position
         return FALSE;
     }
-//    return FALSE;
+
+    return ok;
 }
 
 #endif // wxUSE_STREAMS
@@ -1298,10 +1468,10 @@ bool wxImageHandler::CanRead( const wxString& name )
 
 
 //-----------------------------------------------------------------------------
-// wxBitmap convertion routines
+// Deprecated wxBitmap conversion routines
 //-----------------------------------------------------------------------------
 
-#if wxUSE_GUI
+#if WXWIN_COMPATIBILITY_2_2 && wxUSE_GUI
 
 #ifdef __WXGTK__
 wxBitmap wxImage::ConvertToMonoBitmap( unsigned char red, unsigned char green, unsigned char blue ) const
@@ -1323,27 +1493,72 @@ wxImage::wxImage( const wxBitmap &bitmap )
     *this = bitmap.ConvertToImage();
 }
 
-#endif
+#endif // WXWIN_COMPATIBILITY_2_2 && wxUSE_GUI
 
 
+// ----------------------------------------------------------------------------
+// image histogram stuff
+// ----------------------------------------------------------------------------
 
-// A module to allow wxImage initialization/cleanup
-// without calling these functions from app.cpp or from
-// the user's application.
+bool
+wxImageHistogram::FindFirstUnusedColour(unsigned char *r,
+                                        unsigned char *g,
+                                        unsigned char *b,
+                                        unsigned char r2,
+                                        unsigned char b2,
+                                        unsigned char g2) const
+{
+    unsigned long key = MakeKey(r2, g2, b2);
 
-class wxImageModule: public wxModule
+    while ( find(key) != end() )
+    {
+        // color already used
+        r2++;
+        if ( r2 >= 255 )
+        {
+            r2 = 0;
+            g2++;
+            if ( g2 >= 255 )
+            {
+                g2 = 0;
+                b2++;
+                if ( b2 >= 255 )
+                {
+                    wxLogError(_("GetUnusedColour:: No Unused Color in image ") );
+                    return FALSE;
+                }
+            }
+        }
+
+        key = MakeKey(r2, g2, b2);
+    }
+
+    if ( r )
+        *r = r2;
+    if ( g )
+        *g = g2;
+    if ( b )
+        *b = b2;
+
+    return TRUE;
+}
+
+bool
+wxImage::FindFirstUnusedColour(unsigned char *r,
+                               unsigned char *g,
+                               unsigned char *b,
+                               unsigned char r2,
+                               unsigned char b2,
+                               unsigned char g2) const
 {
-DECLARE_DYNAMIC_CLASS(wxImageModule)
-public:
-    wxImageModule() {}
-    bool OnInit() { wxImage::InitStandardHandlers(); return TRUE; };
-    void OnExit() { wxImage::CleanUpHandlers(); };
-};
+    wxImageHistogram histogram;
 
-IMPLEMENT_DYNAMIC_CLASS(wxImageModule, wxModule)
+    ComputeHistogram(histogram);
+
+    return histogram.FindFirstUnusedColour(r, g, b, r2, g2, b2);
+}
 
 
-//-----------------------------------------------------------------------------
 
 // GRG, Dic/99
 // Counts and returns the number of different colours. Optionally stops
@@ -1369,7 +1584,7 @@ unsigned long wxImage::CountColours( unsigned long stopafter ) const
         r = *(p++);
         g = *(p++);
         b = *(p++);
-        key = (r << 16) | (g << 8) | b;
+        key = wxImageHistogram::MakeKey(r, g, b);
 
         if (h.Get(key) == NULL)
         {
@@ -1384,24 +1599,22 @@ unsigned long wxImage::CountColours( unsigned long stopafter ) const
 
 unsigned long wxImage::ComputeHistogram( wxImageHistogram &h ) const
 {
-    unsigned char r, g, b;
-    unsigned char *p;
-    unsigned long size, nentries, key;
+    unsigned char *p = GetData();
+    unsigned long nentries = 0;
 
     h.clear();
 
-    p = GetData();
-    size = GetWidth() * GetHeight();
-    nentries = 0;
+    const unsigned long size = GetWidth() * GetHeight();
 
-    for (unsigned long j = 0; j < size; j++)
+    unsigned char r, g, b;
+    for ( unsigned long n = 0; n < size; n++ )
     {
-        r = *(p++);
-        g = *(p++);
-        b = *(p++);
-        key = (r << 16) | (g << 8) | b;
+        r = *p++;
+        g = *p++;
+        b = *p++;
+
+        wxImageHistogramEntry& entry = h[wxImageHistogram::MakeKey(r, g, b)];
 
-        wxImageHistogramEntry& entry = h[key];
         if ( entry.value++ == 0 )
             entry.index = nentries++;
     }
@@ -1667,4 +1880,24 @@ wxImage wxImage::Rotate(double angle, const wxPoint & centre_of_rotation, bool i
     return rotated;
 }
 
+
+
+
+
+// A module to allow wxImage initialization/cleanup
+// without calling these functions from app.cpp or from
+// the user's application.
+
+class wxImageModule: public wxModule
+{
+DECLARE_DYNAMIC_CLASS(wxImageModule)
+public:
+    wxImageModule() {}
+    bool OnInit() { wxImage::InitStandardHandlers(); return TRUE; };
+    void OnExit() { wxImage::CleanUpHandlers(); };
+};
+
+IMPLEMENT_DYNAMIC_CLASS(wxImageModule, wxModule)
+
+
 #endif // wxUSE_IMAGE