Remove fixed size of gs_encodingNames array in font mapper code.

[wxWidgets.git] / src / common / imagpng.cpp

diff --git a/src/common/imagpng.cpp b/src/common/imagpng.cpp
index 07f0c8ad544162471b8a5a02917e9879cac30072..5b151d568d7d9ea540859bd33c2733df8e625b5e 100644 (file)
--- a/src/common/imagpng.cpp
+++ b/src/common/imagpng.cpp
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        src/common/imagepng.cpp
+// Name:        src/common/imagpng.cpp

 // Purpose:     wxImage PNG handler
 // Author:      Robert Roebling
 // RCS-ID:      $Id$
 // Purpose:     wxImage PNG handler
 // Author:      Robert Roebling
 // RCS-ID:      $Id$


@@ -24,33 +24,26 @@
 
 #if wxUSE_IMAGE && wxUSE_LIBPNG
 
 
 #if wxUSE_IMAGE && wxUSE_LIBPNG
 

+#include "wx/imagpng.h"
+#include "wx/versioninfo.h"
+

 #ifndef WX_PRECOMP
     #include "wx/log.h"
 #ifndef WX_PRECOMP
     #include "wx/log.h"

-    #include "wx/app.h"
+    #include "wx/intl.h"
+    #include "wx/palette.h"
+    #include "wx/stream.h"

 #endif
 
 #endif
 

-#include "wx/imagpng.h"
-#include "wx/bitmap.h"

 #include "png.h"
 #include "png.h"

-#include "wx/filefn.h"
-#include "wx/wfstream.h"
-#include "wx/intl.h"
-#include "wx/module.h"

 
 // For memcpy
 #include <string.h>
 
 
 // For memcpy
 #include <string.h>
 

-#ifdef __SALFORDC__
-#ifdef FAR
-#undef FAR
-#endif
-#endif
-

 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------
 

-// image can not have any transparent pixels at all, have only 100% opaque
+// image cannot have any transparent pixels at all, have only 100% opaque

 // and/or 100% transparent pixels in which case a simple mask is enough to
 // store this information in wxImage or have a real alpha channel in which case
 // we need to have it in wxImage as well
 // and/or 100% transparent pixels in which case a simple mask is enough to
 // store this information in wxImage or have a real alpha channel in which case
 // we need to have it in wxImage as well


@@ -103,7 +96,9 @@ IMPLEMENT_DYNAMIC_CLASS(wxPNGHandler,wxImageHandler)
 #if wxUSE_STREAMS
 
 #ifndef PNGLINKAGEMODE
 #if wxUSE_STREAMS
 
 #ifndef PNGLINKAGEMODE

-    #if defined(__WATCOMC__) && ( defined(__WXMSW__) || defined(__WXMGL__) )
+    #ifdef PNGAPI
+        #define PNGLINKAGEMODE PNGAPI
+    #elif defined(__WATCOMC__)

         // we need an explicit cdecl for Watcom, at least according to
         //
         // http://sf.net/tracker/index.php?func=detail&aid=651492&group_id=9863&atid=109863
         // we need an explicit cdecl for Watcom, at least according to
         //
         // http://sf.net/tracker/index.php?func=detail&aid=651492&group_id=9863&atid=109863


@@ -154,29 +149,31 @@ struct wxPNGInfoStruct
 extern "C"
 {
 
 extern "C"
 {
 

-void PNGLINKAGEMODE wx_PNG_stream_reader( png_structp png_ptr, png_bytep data,
-                                          png_size_t length )
+static void PNGLINKAGEMODE wx_PNG_stream_reader( png_structp png_ptr, png_bytep data,
+                                                 png_size_t length )

 {
     WX_PNG_INFO(png_ptr)->stream.in->Read(data, length);
 }
 
 {
     WX_PNG_INFO(png_ptr)->stream.in->Read(data, length);
 }
 

-void PNGLINKAGEMODE wx_PNG_stream_writer( png_structp png_ptr, png_bytep data,
-                                          png_size_t length )
+static void PNGLINKAGEMODE wx_PNG_stream_writer( png_structp png_ptr, png_bytep data,
+                                                 png_size_t length )

 {
     WX_PNG_INFO(png_ptr)->stream.out->Write(data, length);
 }
 
 {
     WX_PNG_INFO(png_ptr)->stream.out->Write(data, length);
 }
 

-void
+static void

 PNGLINKAGEMODE wx_png_warning(png_structp png_ptr, png_const_charp message)
 {
     wxPNGInfoStruct *info = png_ptr ? WX_PNG_INFO(png_ptr) : NULL;
     if ( !info || info->verbose )
 PNGLINKAGEMODE wx_png_warning(png_structp png_ptr, png_const_charp message)
 {
     wxPNGInfoStruct *info = png_ptr ? WX_PNG_INFO(png_ptr) : NULL;
     if ( !info || info->verbose )

+    {

         wxLogWarning( wxString::FromAscii(message) );
         wxLogWarning( wxString::FromAscii(message) );

+    }

 }
 
 // from pngerror.c
 // so that the libpng doesn't send anything on stderr
 }
 
 // from pngerror.c
 // so that the libpng doesn't send anything on stderr

-void
+static void

 PNGLINKAGEMODE wx_png_error(png_structp png_ptr, png_const_charp message)
 {
     wx_png_warning(NULL, message);
 PNGLINKAGEMODE wx_png_error(png_structp png_ptr, png_const_charp message)
 {
     wx_png_warning(NULL, message);


@@ -277,6 +274,7 @@ FindMaskColour(unsigned char **lines, png_uint_32 width, png_uint_32 height,
             r2 = *p++;
             g2 = *p++;
             b2 = *p++;
             r2 = *p++;
             g2 = *p++;
             b2 = *p++;

+            ++p; // jump over alpha

 
             wxImageHistogramEntry&
                 entry = h[wxImageHistogram:: MakeKey(r2, g2, b2)];
 
             wxImageHistogramEntry&
                 entry = h[wxImageHistogram:: MakeKey(r2, g2, b2)];


@@ -307,7 +305,7 @@ bool wxPNGHandler::DoCanRead( wxInputStream& stream )
 {
     unsigned char hdr[4];
 
 {
     unsigned char hdr[4];
 

-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
+    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )     // it's ok to modify the stream position here

         return false;
 
     return memcmp(hdr, "\211PNG", WXSIZEOF(hdr)) == 0;
         return false;
 
     return memcmp(hdr, "\211PNG", WXSIZEOF(hdr)) == 0;


@@ -382,15 +380,15 @@ void CopyDataFromPNG(wxImage *image,
                         if ( IsTransparent(a) )
                         {
                             *ptrDst++ = rMask;
                         if ( IsTransparent(a) )
                         {
                             *ptrDst++ = rMask;

-                            *ptrDst++ = bMask;

                             *ptrDst++ = gMask;
                             *ptrDst++ = gMask;

+                            *ptrDst++ = bMask;

                             break;
                         }
                         // else: !transparent
 
                         // must be opaque then as otherwise we shouldn't be
                         // using the mask at all
                             break;
                         }
                         // else: !transparent
 
                         // must be opaque then as otherwise we shouldn't be
                         // using the mask at all

-                        wxASSERT_MSG( IsOpaque(a), _T("logic error") );
+                        wxASSERT_MSG( IsOpaque(a), wxT("logic error") );

 
                         // fall through
 
 
                         // fall through
 


@@ -450,15 +448,15 @@ void CopyDataFromPNG(wxImage *image,
                         if ( IsTransparent(a) )
                         {
                             *ptrDst++ = rMask;
                         if ( IsTransparent(a) )
                         {
                             *ptrDst++ = rMask;

-                            *ptrDst++ = bMask;

                             *ptrDst++ = gMask;
                             *ptrDst++ = gMask;

+                            *ptrDst++ = bMask;

                             break;
                         }
                         else // !transparent
                         {
                             // must be opaque then as otherwise we shouldn't be
                             // using the mask at all
                             break;
                         }
                         else // !transparent
                         {
                             // must be opaque then as otherwise we shouldn't be
                             // using the mask at all

-                            wxASSERT_MSG( IsOpaque(a), _T("logic error") );
+                            wxASSERT_MSG( IsOpaque(a), wxT("logic error") );

 
                             // if we couldn't find a unique colour for the
                             // mask, we can have real pixels with the same
 
                             // if we couldn't find a unique colour for the
                             // mask, we can have real pixels with the same


@@ -524,7 +522,7 @@ wxPNGHandler::LoadFile(wxImage *image,
     png_structp png_ptr = png_create_read_struct
                           (
                             PNG_LIBPNG_VER_STRING,
     png_structp png_ptr = png_create_read_struct
                           (
                             PNG_LIBPNG_VER_STRING,

-                            (voidp) NULL,
+                            NULL,

                             wx_png_error,
                             wx_png_warning
                           );
                             wx_png_error,
                             wx_png_warning
                           );


@@ -543,7 +541,7 @@ wxPNGHandler::LoadFile(wxImage *image,
         goto error;
 
     png_read_info( png_ptr, info_ptr );
         goto error;
 
     png_read_info( png_ptr, info_ptr );

-    png_get_IHDR( png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, (int*) NULL, (int*) NULL );
+    png_get_IHDR( png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL );

 
     if (color_type == PNG_COLOR_TYPE_PALETTE)
         png_set_expand( png_ptr );
 
     if (color_type == PNG_COLOR_TYPE_PALETTE)
         png_set_expand( png_ptr );


@@ -563,22 +561,88 @@ wxPNGHandler::LoadFile(wxImage *image,
     if (!image->Ok())
         goto error;
 
     if (!image->Ok())
         goto error;
 

-    lines = (unsigned char **)malloc( (size_t)(height * sizeof(unsigned char *)) );
+    // initialize all line pointers to NULL to ensure that they can be safely
+    // free()d if an error occurs before all of them could be allocated
+    lines = (unsigned char **)calloc(height, sizeof(unsigned char *));

     if ( !lines )
         goto error;
 
     for (i = 0; i < height; i++)
     {
         if ((lines[i] = (unsigned char *)malloc( (size_t)(width * (sizeof(unsigned char) * 4)))) == NULL)
     if ( !lines )
         goto error;
 
     for (i = 0; i < height; i++)
     {
         if ((lines[i] = (unsigned char *)malloc( (size_t)(width * (sizeof(unsigned char) * 4)))) == NULL)

-        {
-            for ( unsigned int n = 0; n < i; n++ )
-                free( lines[n] );

             goto error;
             goto error;

-        }

     }
 
     png_read_image( png_ptr, lines );
     png_read_end( png_ptr, info_ptr );
     }
 
     png_read_image( png_ptr, lines );
     png_read_end( png_ptr, info_ptr );

+
+#if wxUSE_PALETTE
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+    {
+        png_colorp palette = NULL;
+        int numPalette = 0;
+
+        (void) png_get_PLTE(png_ptr, info_ptr, &palette, &numPalette);
+
+        unsigned char* r = new unsigned char[numPalette];
+        unsigned char* g = new unsigned char[numPalette];
+        unsigned char* b = new unsigned char[numPalette];
+
+        for (int j = 0; j < numPalette; j++)
+        {
+            r[j] = palette[j].red;
+            g[j] = palette[j].green;
+            b[j] = palette[j].blue;
+        }
+
+        image->SetPalette(wxPalette(numPalette, r, g, b));
+        delete[] r;
+        delete[] g;
+        delete[] b;
+    }
+#endif // wxUSE_PALETTE
+
+
+    // set the image resolution if it's available
+    png_uint_32 resX, resY;
+    int unitType;
+    if (png_get_pHYs(png_ptr, info_ptr, &resX, &resY, &unitType)
+        == PNG_INFO_pHYs)
+    {
+        wxImageResolution res = wxIMAGE_RESOLUTION_CM;
+
+        switch (unitType)
+        {
+            default:
+                wxLogWarning(_("Unknown PNG resolution unit %d"), unitType);
+                // fall through
+
+            case PNG_RESOLUTION_UNKNOWN:
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, resX);
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, resY);
+
+                res = wxIMAGE_RESOLUTION_NONE;
+                break;
+
+            case PNG_RESOLUTION_METER:
+                /*
+                Convert meters to centimeters.
+                Use a string to not lose precision (converting to cm and then
+                to inch would result in integer rounding error).
+                If an app wants an int, GetOptionInt will convert and round
+                down for them.
+                */
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONX,
+                    wxString::FromCDouble((double) resX / 100.0, 2));
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONY,
+                    wxString::FromCDouble((double) resY / 100.0, 2));
+                break;
+        }
+
+        image->SetOption(wxIMAGE_OPTION_RESOLUTIONUNIT, res);
+    }
+
+

     png_destroy_read_struct( &png_ptr, &info_ptr, (png_infopp) NULL );
 
     // loaded successfully, now init wxImage with this data
     png_destroy_read_struct( &png_ptr, &info_ptr, (png_infopp) NULL );
 
     // loaded successfully, now init wxImage with this data


@@ -592,7 +656,9 @@ wxPNGHandler::LoadFile(wxImage *image,
 
 error:
     if (verbose)
 
 error:
     if (verbose)

+    {

        wxLogError(_("Couldn't load a PNG image - file is corrupted or not enough memory."));
        wxLogError(_("Couldn't load a PNG image - file is corrupted or not enough memory."));

+    }

 
     if ( image->Ok() )
     {
 
     if ( image->Ok() )
     {


@@ -620,6 +686,44 @@ error:
     return false;
 }
 
     return false;
 }
 

+// ----------------------------------------------------------------------------
+// SaveFile() palette helpers
+// ----------------------------------------------------------------------------
+
+typedef wxLongToLongHashMap PaletteMap;
+
+static unsigned long PaletteMakeKey(const png_color_8& clr)
+{
+    return (wxImageHistogram::MakeKey(clr.red, clr.green, clr.blue) << 8) | clr.alpha;
+}
+
+static long PaletteFind(const PaletteMap& palette, const png_color_8& clr)
+{
+    unsigned long value = PaletteMakeKey(clr);
+    PaletteMap::const_iterator it = palette.find(value);
+
+    return (it != palette.end()) ? it->second : wxNOT_FOUND;
+}
+
+static long PaletteAdd(PaletteMap *palette, const png_color_8& clr)
+{
+    unsigned long value = PaletteMakeKey(clr);
+    PaletteMap::const_iterator it = palette->find(value);
+    size_t index;
+
+    if (it == palette->end())
+    {
+        index = palette->size();
+        (*palette)[value] = index;
+    }
+    else
+    {
+        index = it->second;
+    }
+
+    return index;
+}
+

 // ----------------------------------------------------------------------------
 // writing PNGs
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // writing PNGs
 // ----------------------------------------------------------------------------


@@ -641,7 +745,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
     if (!png_ptr)
     {
         if (verbose)
     if (!png_ptr)
     {
         if (verbose)

+        {

            wxLogError(_("Couldn't save PNG image."));
            wxLogError(_("Couldn't save PNG image."));

+        }

         return false;
     }
 
         return false;
     }
 


@@ -650,7 +756,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
     {
         png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
         if (verbose)
     {
         png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
         if (verbose)

+        {

            wxLogError(_("Couldn't save PNG image."));
            wxLogError(_("Couldn't save PNG image."));

+        }

         return false;
     }
 
         return false;
     }
 


@@ -658,7 +766,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
     {
         png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
         if (verbose)
     {
         png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
         if (verbose)

+        {

            wxLogError(_("Couldn't save PNG image."));
            wxLogError(_("Couldn't save PNG image."));

+        }

         return false;
     }
 
         return false;
     }
 


@@ -666,22 +776,119 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
     //     explanation why this line is mandatory
     png_set_write_fn( png_ptr, &wxinfo, wx_PNG_stream_writer, NULL);
 
     //     explanation why this line is mandatory
     png_set_write_fn( png_ptr, &wxinfo, wx_PNG_stream_writer, NULL);
 

-    const int iColorType = image->HasOption(wxIMAGE_OPTION_PNG_FORMAT)
+    const int iHeight = image->GetHeight();
+    const int iWidth = image->GetWidth();
+
+    const bool bHasPngFormatOption
+        = image->HasOption(wxIMAGE_OPTION_PNG_FORMAT);
+
+    int iColorType = bHasPngFormatOption

                             ? image->GetOptionInt(wxIMAGE_OPTION_PNG_FORMAT)
                             : wxPNG_TYPE_COLOUR;
                             ? image->GetOptionInt(wxIMAGE_OPTION_PNG_FORMAT)
                             : wxPNG_TYPE_COLOUR;

-    const int iBitDepth = image->HasOption(wxIMAGE_OPTION_PNG_BITDEPTH)
-                            ? image->GetOptionInt(wxIMAGE_OPTION_PNG_BITDEPTH)
-                            : 8;
-
-    wxASSERT_MSG( iBitDepth == 8 || iBitDepth == 16,
-                    _T("PNG bit depth must be 8 or 16") );

 
     bool bHasAlpha = image->HasAlpha();
     bool bHasMask = image->HasMask();
 
     bool bHasAlpha = image->HasAlpha();
     bool bHasMask = image->HasMask();

-    bool bUseAlpha = bHasAlpha || bHasMask;
+
+    bool bUsePalette = iColorType == wxPNG_TYPE_PALETTE
+#if wxUSE_PALETTE
+        || (!bHasPngFormatOption && image->HasPalette() )
+#endif
+    ;
+
+    png_color_8 mask;
+
+    if (bHasMask)
+    {
+        mask.red   = image->GetMaskRed();
+        mask.green = image->GetMaskGreen();
+        mask.blue  = image->GetMaskBlue();
+        mask.alpha = 0;
+        mask.gray  = 0;
+    }
+
+    PaletteMap palette;
+
+    if (bUsePalette)
+    {
+        png_color png_rgb  [PNG_MAX_PALETTE_LENGTH];
+        png_byte  png_trans[PNG_MAX_PALETTE_LENGTH];
+
+        const unsigned char *pColors = image->GetData();
+        const unsigned char* pAlpha  = image->GetAlpha();
+
+        if (bHasMask && !pAlpha)
+        {
+            // Mask must be first
+            PaletteAdd(&palette, mask);
+        }
+
+        for (int y = 0; y < iHeight; y++)
+        {
+            for (int x = 0; x < iWidth; x++)
+            {
+                png_color_8 rgba;
+
+                rgba.red   = *pColors++;
+                rgba.green = *pColors++;
+                rgba.blue  = *pColors++;
+                rgba.gray  = 0;
+                rgba.alpha = (pAlpha && !bHasMask) ? *pAlpha++ : 0;
+
+                // save in our palette
+                long index = PaletteAdd(&palette, rgba);
+
+                if (index < PNG_MAX_PALETTE_LENGTH)
+                {
+                    // save in libpng's palette
+                    png_rgb[index].red   = rgba.red;
+                    png_rgb[index].green = rgba.green;
+                    png_rgb[index].blue  = rgba.blue;
+                    png_trans[index]     = rgba.alpha;
+                }
+                else
+                {
+                    bUsePalette = false;
+                    break;
+                }
+            }
+        }
+
+        if (bUsePalette)
+        {
+            png_set_PLTE(png_ptr, info_ptr, png_rgb, palette.size());
+
+            if (bHasMask && !pAlpha)
+            {
+                wxASSERT(PaletteFind(palette, mask) == 0);
+                png_trans[0] = 0;
+                png_set_tRNS(png_ptr, info_ptr, png_trans, 1, NULL);
+            }
+            else if (pAlpha && !bHasMask)
+            {
+                png_set_tRNS(png_ptr, info_ptr, png_trans, palette.size(), NULL);
+            }
+        }
+    }
+
+    /*
+    If saving palettised was requested but it was decided we can't use a
+    palette then reset the colour type to RGB.
+    */
+    if (!bUsePalette && iColorType == wxPNG_TYPE_PALETTE)
+    {
+        iColorType = wxPNG_TYPE_COLOUR;
+    }
+
+    bool bUseAlpha = !bUsePalette && (bHasAlpha || bHasMask);

 
     int iPngColorType;
 
     int iPngColorType;

-    if ( iColorType==wxPNG_TYPE_COLOUR )
+
+    if (bUsePalette)
+    {
+        iPngColorType = PNG_COLOR_TYPE_PALETTE;
+        iColorType = wxPNG_TYPE_PALETTE;
+    }
+    else if ( iColorType==wxPNG_TYPE_COLOUR )

     {
         iPngColorType = bUseAlpha ? PNG_COLOR_TYPE_RGB_ALPHA
                                   : PNG_COLOR_TYPE_RGB;
     {
         iPngColorType = bUseAlpha ? PNG_COLOR_TYPE_RGB_ALPHA
                                   : PNG_COLOR_TYPE_RGB;


@@ -692,6 +899,25 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
                                   : PNG_COLOR_TYPE_GRAY;
     }
 
                                   : PNG_COLOR_TYPE_GRAY;
     }
 

+    if (image->HasOption(wxIMAGE_OPTION_PNG_FILTER))
+        png_set_filter( png_ptr, PNG_FILTER_TYPE_BASE, image->GetOptionInt(wxIMAGE_OPTION_PNG_FILTER) );
+
+    if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL))
+        png_set_compression_level( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL) );
+
+    if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL))
+        png_set_compression_mem_level( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL) );
+
+    if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY))
+        png_set_compression_strategy( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY) );
+
+    if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE))
+        png_set_compression_buffer_size( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE) );
+
+    int iBitDepth = !bUsePalette && image->HasOption(wxIMAGE_OPTION_PNG_BITDEPTH)
+                            ? image->GetOptionInt(wxIMAGE_OPTION_PNG_BITDEPTH)
+                            : 8;
+

     png_set_IHDR( png_ptr, info_ptr, image->GetWidth(), image->GetHeight(),
                   iBitDepth, iPngColorType,
                   PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,
     png_set_IHDR( png_ptr, info_ptr, image->GetWidth(), image->GetHeight(),
                   iBitDepth, iPngColorType,
                   PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,


@@ -713,7 +939,7 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
         iElements = 1;
     }
 
         iElements = 1;
     }
 

-    if ( iPngColorType & PNG_COLOR_MASK_ALPHA )
+    if ( bUseAlpha )

     {
         sig_bit.alpha = (png_byte)iBitDepth;
         iElements++;
     {
         sig_bit.alpha = (png_byte)iBitDepth;
         iElements++;


@@ -722,6 +948,33 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
     if ( iBitDepth == 16 )
         iElements *= 2;
 
     if ( iBitDepth == 16 )
         iElements *= 2;
 

+    // save the image resolution if we have it
+    int resX, resY;
+    switch ( GetResolutionFromOptions(*image, &resX, &resY) )
+    {
+        case wxIMAGE_RESOLUTION_INCHES:
+            {
+                const double INCHES_IN_METER = 10000.0 / 254;
+                resX = int(resX * INCHES_IN_METER);
+                resY = int(resY * INCHES_IN_METER);
+            }
+            break;
+
+        case wxIMAGE_RESOLUTION_CM:
+            resX *= 100;
+            resY *= 100;
+            break;
+
+        case wxIMAGE_RESOLUTION_NONE:
+            break;
+
+        default:
+            wxFAIL_MSG( wxT("unsupported image resolution units") );
+    }
+
+    if ( resX && resY )
+        png_set_pHYs( png_ptr, info_ptr, resX, resY, PNG_RESOLUTION_METER );
+

     png_set_sBIT( png_ptr, info_ptr, &sig_bit );
     png_write_info( png_ptr, info_ptr );
     png_set_shift( png_ptr, &sig_bit );
     png_set_sBIT( png_ptr, info_ptr, &sig_bit );
     png_write_info( png_ptr, info_ptr );
     png_set_shift( png_ptr, &sig_bit );


@@ -735,45 +988,37 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
         return false;
     }
 
         return false;
     }
 

-    unsigned char *
-        pAlpha = (unsigned char *)(bHasAlpha ? image->GetAlpha() : NULL);
-    int iHeight = image->GetHeight();
-    int iWidth = image->GetWidth();
+    const unsigned char *
+        pAlpha = (const unsigned char *)(bHasAlpha ? image->GetAlpha() : NULL);

 
 

-    unsigned char uchMaskRed = 0, uchMaskGreen = 0, uchMaskBlue = 0;
-
-    if ( bHasMask )
-    {
-        uchMaskRed = image->GetMaskRed();
-        uchMaskGreen = image->GetMaskGreen();
-        uchMaskBlue = image->GetMaskBlue();
-    }
-
-    unsigned char *pColors = image->GetData();
+    const unsigned char *pColors = image->GetData();

 
     for (int y = 0; y != iHeight; ++y)
     {
         unsigned char *pData = data;
         for (int x = 0; x != iWidth; x++)
         {
 
     for (int y = 0; y != iHeight; ++y)
     {
         unsigned char *pData = data;
         for (int x = 0; x != iWidth; x++)
         {

-            unsigned char uchRed = *pColors++;
-            unsigned char uchGreen = *pColors++;
-            unsigned char uchBlue = *pColors++;
+            png_color_8 clr;
+            clr.red   = *pColors++;
+            clr.green = *pColors++;
+            clr.blue  = *pColors++;
+            clr.gray  = 0;
+            clr.alpha = (bUsePalette && pAlpha) ? *pAlpha++ : 0; // use with wxPNG_TYPE_PALETTE only

 
             switch ( iColorType )
             {
                 default:
 
             switch ( iColorType )
             {
                 default:

-                    wxFAIL_MSG( _T("unknown wxPNG_TYPE_XXX") );
+                    wxFAIL_MSG( wxT("unknown wxPNG_TYPE_XXX") );

                     // fall through
 
                 case wxPNG_TYPE_COLOUR:
                     // fall through
 
                 case wxPNG_TYPE_COLOUR:

-                    *pData++ = uchRed;
+                    *pData++ = clr.red;

                     if ( iBitDepth == 16 )
                         *pData++ = 0;
                     if ( iBitDepth == 16 )
                         *pData++ = 0;

-                    *pData++ = uchGreen;
+                    *pData++ = clr.green;

                     if ( iBitDepth == 16 )
                         *pData++ = 0;
                     if ( iBitDepth == 16 )
                         *pData++ = 0;

-                    *pData++ = uchBlue;
+                    *pData++ = clr.blue;

                     if ( iBitDepth == 16 )
                         *pData++ = 0;
                     break;
                     if ( iBitDepth == 16 )
                         *pData++ = 0;
                     break;


@@ -783,9 +1028,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
                         // where do these coefficients come from? maybe we
                         // should have image options for them as well?
                         unsigned uiColor =
                         // where do these coefficients come from? maybe we
                         // should have image options for them as well?
                         unsigned uiColor =

-                            (unsigned) (76.544*(unsigned)uchRed +
-                                        150.272*(unsigned)uchGreen +
-                                        36.864*(unsigned)uchBlue);
+                            (unsigned) (76.544*(unsigned)clr.red +
+                                        150.272*(unsigned)clr.green +
+                                        36.864*(unsigned)clr.blue);

 
                         *pData++ = (unsigned char)((uiColor >> 8) & 0xFF);
                         if ( iBitDepth == 16 )
 
                         *pData++ = (unsigned char)((uiColor >> 8) & 0xFF);
                         if ( iBitDepth == 16 )


@@ -794,10 +1039,14 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
                     break;
 
                 case wxPNG_TYPE_GREY_RED:
                     break;
 
                 case wxPNG_TYPE_GREY_RED:

-                    *pData++ = uchRed;
+                    *pData++ = clr.red;

                     if ( iBitDepth == 16 )
                         *pData++ = 0;
                     break;
                     if ( iBitDepth == 16 )
                         *pData++ = 0;
                     break;

+
+                case wxPNG_TYPE_PALETTE:
+                    *pData++ = (unsigned char) PaletteFind(palette, clr);
+                    break;

             }
 
             if ( bUseAlpha )
             }
 
             if ( bUseAlpha )


@@ -808,9 +1057,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
 
                 if ( bHasMask )
                 {
 
                 if ( bHasMask )
                 {

-                    if ( (uchRed == uchMaskRed)
-                            && (uchGreen == uchMaskGreen)
-                                && (uchBlue == uchMaskBlue) )
+                    if ( (clr.red == mask.red)
+                            && (clr.green == mask.green)
+                                && (clr.blue == mask.blue) )

                         uchAlpha = 0;
                 }
 
                         uchAlpha = 0;
                 }
 


@@ -837,4 +1086,18 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
 
 #endif  // wxUSE_STREAMS
 
 
 #endif  // wxUSE_STREAMS
 

+/*static*/ wxVersionInfo wxPNGHandler::GetLibraryVersionInfo()
+{
+    // The version string seems to always have a leading space and a trailing
+    // new line, get rid of them both.
+    wxString str = png_get_header_version(NULL) + 1;
+    str.Replace("\n", "");
+
+    return wxVersionInfo("libpng",
+                         PNG_LIBPNG_VER_MAJOR,
+                         PNG_LIBPNG_VER_MINOR,
+                         PNG_LIBPNG_VER_RELEASE,
+                         str);
+}
+

 #endif  // wxUSE_LIBPNG
 #endif  // wxUSE_LIBPNG