Method ReadImageCache

libraries/lib-theme/Theme.cpp:842–970

Reads an image cache including images, cursors and colours. @param type if empty means read from an external binary file. otherwise the data is taken from a block of memory. @param bOkIfNotFound if true means do not report absent file. @return true iff we loaded the images.

/// @param bOkIfNotFound if true means do not report absent file.
/// @return true iff we loaded the images.
bool ThemeBase::ReadImageCache( teThemeType type, bool bOkIfNotFound)
{
   auto &resources = *mpSet;
   EnsureInitialised();
   wxImage ImageCache;

   // Ensure we have an alpha channel...
//   if( !ImageCache.HasAlpha() )
//   {
//      ImageCache.InitAlpha();
//   }

   using namespace BasicUI;

   if( type.empty() || type == "custom" )
   {
      mPreferredSystemAppearance = PreferredSystemAppearance::Light;

      // Take the image cache file for the theme chosen in preferences
      auto dir = ThemeSubdir(GetFilePath(), GUITheme().Read());
      const auto &FileName =
         wxFileName{ dir, ImageCacheFileName }.GetFullPath();
      if( !wxFileExists( FileName ))
      {
         if( bOkIfNotFound )
            return false; // did not load the images, so return false.
         ShowMessageBox(
            XO("Audacity could not find file:\n  %s.\nTheme not loaded.")
               .Format( FileName ));
         return false;
      }
      if( !ImageCache.LoadFile( FileName, wxBITMAP_TYPE_PNG ))
      {
         ShowMessageBox(
            /* i18n-hint: Do not translate png.  It is the name of a file format.*/
            XO("Audacity could not load file:\n  %s.\nBad png format perhaps?")
               .Format( FileName ));
         return false;
      }
   }
   // ELSE we are reading from internal storage.
   else
   {
      size_t ImageSize = 0;
      const unsigned char * pImage = nullptr;
      auto &lookup = GetThemeCacheLookup();
      auto iter = lookup.find({type, {}});
      if (const auto end = lookup.end(); iter == end) {
         iter = lookup.find({"classic", {}});
         wxASSERT(iter != end);
      }

      mPreferredSystemAppearance = iter->second.preferredSystemAppearance;

      ImageSize = iter->second.data.size();
      if (ImageSize == 0)
         // This must be the image compiler
         return true;