optimize handling of high-res native images

include/wx/osx/cocoa/private.h

@@ -41,7 +41,7 @@ WX_NSImage WXDLLIMPEXP_CORE wxOSXGetNSImageFromCGImage( CGImageRef image, double
 WX_NSImage WXDLLIMPEXP_CORE wxOSXGetNSImageFromIconRef( WXHICON iconref );
 WX_NSImage WXDLLIMPEXP_CORE wxOSXGetIconForType(OSType type );
 void WXDLLIMPEXP_CORE wxOSXSetImageSize(WX_NSImage image, CGFloat width, CGFloat height);
-
+double WXDLLIMPEXP_CORE wxOSXGetImageScaleFactor(WXImage image);
 wxBitmap WXDLLIMPEXP_CORE wxOSXCreateSystemBitmap(const wxString& id, const wxString &client, const wxSize& size);
 WXWindow WXDLLIMPEXP_CORE wxOSXGetMainWindow();
 WXWindow WXDLLIMPEXP_CORE wxOSXGetKeyWindow();

include/wx/osx/core/private.h

@@ -104,8 +104,6 @@ protected :
 
 // Quartz
 
-WXDLLIMPEXP_CORE CGImageRef wxMacCreateCGImageFromBitmap( const wxBitmap& bitmap );
-
 WXDLLIMPEXP_CORE CGDataProviderRef wxMacCGDataProviderCreateWithCFData( CFDataRef data );
 WXDLLIMPEXP_CORE CGDataConsumerRef wxMacCGDataConsumerCreateWithCFData( CFMutableDataRef data );
 WXDLLIMPEXP_CORE CGDataProviderRef wxMacCGDataProviderCreateWithMemoryBuffer( const wxMemoryBuffer& buf );

src/osx/carbon/utilscocoa.mm

@@ -248,11 +248,7 @@ CGContextRef WXDLLIMPEXP_CORE wxOSXCreateBitmapContextFromImage( WXImage nsimage
     {
         double scale = wxOSXGetMainScreenContentScaleFactor();
 
-#if wxOSX_USE_COCOA
-        NSSize imageSize = [nsimage size];
-#else
-        CGSize imageSize = [nsimage size];
-#endif
+        CGSize imageSize = wxOSXGetImageSize(nsimage);
         
         hbitmap = CGBitmapContextCreate(NULL, imageSize.width*scale, imageSize.height*scale, 8, 0, wxMacGetGenericRGBColorSpace(), kCGImageAlphaPremultipliedFirst);
         CGContextScaleCTM( hbitmap, scale, scale );
@@ -329,6 +325,20 @@ void wxOSXSetImageSize(WXImage image, CGFloat width, CGFloat height)
 #endif
 }
 
+double wxOSXGetImageScaleFactor(WXImage image)
+{
+#if wxOSX_USE_COCOA
+    NSSize imagesize = [image size];
+    int width = [[image bestRepresentationForRect:NSMakeRect(0, 0, imagesize.width, imagesize.height) context:nil hints:nil] pixelsWide];
+    if ( width == 0 ) // there are multi-res representations which return 0 for the pixel dimensions
+        return wxOSXGetMainScreenContentScaleFactor();
+
+    return width / [image size].width;
+#else
+    return [image scale];
+#endif
+}
+
 CGSize wxOSXGetImageSize(WXImage image)
 {
 #if wxOSX_USE_COCOA

src/osx/core/bitmap.cpp

@@ -138,20 +138,6 @@ static size_t GetBestBytesPerRow( size_t rawBytes )
     return (((rawBytes)+kBestByteAlignement-1) & ~(kBestByteAlignement-1) );
 }
 
-#if wxUSE_GUI && !defined(__WXOSX_IPHONE__)
-
-// this is used for more controls than just the wxBitmap button, also for notebooks etc
-
-CGImageRef wxMacCreateCGImageFromBitmap( const wxBitmap& bitmap )
-{
-    const wxBitmapRefData * bmap = bitmap.GetBitmapData() ;
-    if ( bmap == NULL )
-        return NULL ;
-    return (CGImageRef) bmap->CreateCGImage();
-}
-
-#endif //wxUSE_BMPBUTTON
-
 void wxBitmapRefData::Init()
 {
     m_nsImage = NULL;
@@ -230,6 +216,8 @@ bool wxBitmapRefData::Create( WXImage image )
 
     wxMacCocoaRetain(image);
 
+    m_scaleFactor = wxOSXGetImageScaleFactor(image);
+
     return true;
 }
 
@@ -289,7 +277,7 @@ bool wxBitmapRefData::Create(int w, int h, int d, double logicalscale)
     size_t m_width = wxMax(1, w);
     size_t m_height = wxMax(1, h);
 
-    int m_scaleFactor = logicalscale;
+    m_scaleFactor = logicalscale;
     m_hBitmap = NULL;
 
     size_t m_bytesPerRow = GetBestBytesPerRow(m_width * 4);
@@ -314,7 +302,7 @@ int wxBitmapRefData::GetWidth() const
     if ( m_hBitmap )
         return (int) CGBitmapContextGetWidth(m_hBitmap);
     else
-        return (int) wxOSXGetImageSize(m_nsImage).width;
+        return (int) wxOSXGetImageSize(m_nsImage).width * m_scaleFactor;
 }
 
 int wxBitmapRefData::GetHeight() const
@@ -324,7 +312,7 @@ int wxBitmapRefData::GetHeight() const
     if ( m_hBitmap )
         return (int) CGBitmapContextGetHeight(m_hBitmap);
     else
-        return (int) wxOSXGetImageSize(m_nsImage).height;
+        return (int) wxOSXGetImageSize(m_nsImage).height * m_scaleFactor;
 }
 
 int wxBitmapRefData::GetDepth() const
@@ -1274,6 +1262,11 @@ wxImage wxBitmap::ConvertToImage() const
 
     wxCHECK_MSG( IsOk(), wxNullImage, wxT("invalid bitmap") );
 
+    // this call may trigger a conversion from platform image to bitmap, issue it
+    // before any measurements are taken, multi-resolution platform images may be
+    // rendered incorrectly otherwise
+    unsigned char* sourcestart = (unsigned char*) GetBitmapData()->GetRawAccess() ;
+
     // create an wxImage object
     int width = GetWidth();
     int height = GetHeight();
@@ -1282,8 +1275,6 @@ wxImage wxBitmap::ConvertToImage() const
     unsigned char *data = image.GetData();
     wxCHECK_MSG( data, wxNullImage, wxT("Could not allocate data for image") );
 
-    unsigned char* sourcestart = (unsigned char*) GetBitmapData()->GetRawAccess() ;
-
     bool hasAlpha = false ;
     bool hasMask = false ;
     int maskBytesPerRow = 0 ;