Fix caching source bitmap in wxD2DBitmapResourceHolder (Direct2D)

Because cached wxBitmap is used only to help in representing native D2D
bitmap in some operations it shouldn't be exposed directly and dedicated
methods should be implemented instead.

src/msw/graphicsd2d.cpp

@@ -2370,9 +2370,48 @@ public:
     wxD2DBitmapResourceHolder(const wxBitmap& sourceBitmap) :
         m_sourceBitmap(sourceBitmap)
     {
+        m_sourceBitmap.MSWBlendMaskWithAlpha();
     }
 
-    const wxBitmap& GetSourceBitmap() const { return m_sourceBitmap; }
+#if wxUSE_IMAGE
+    wxImage ConvertToImage() const
+    {
+        // Never return image with mask because native bitmaps don't have masks
+        wxImage img = m_sourceBitmap.ConvertToImage();
+        if ( img.HasMask() )
+        {
+            if ( !img.HasAlpha() )
+            {
+                img.InitAlpha();
+            }
+            else
+            {
+                // This case should never happen because cached source
+                // bitmap has mask blended with alpha values (in ctor).
+            }
+        }
+        // We need also to remove mask colour from transparent pixels
+        // for compatibility with native D2D bitmap.
+        if ( img.HasAlpha() )
+        {
+            for ( int y = 0; y < img.GetHeight(); y++ )
+            for ( int x = 0; x < img.GetWidth(); x++ )
+            {
+                if ( img.GetAlpha(x, y) == wxALPHA_TRANSPARENT )
+                {
+                    img.SetRGB(x, y, 0, 0, 0);
+                }
+            }
+        }
+
+        return img;
+    }
+#endif // wxUSE_IMAGE
+
+    wxD2DBitmapResourceHolder* GetSubBitmap(wxDouble x, wxDouble y, wxDouble w, wxDouble h) const
+    {
+        return new wxD2DBitmapResourceHolder(m_sourceBitmap.GetSubBitmap(wxRect(x, y, w, h)));
+    }
 
 protected:
     void DoAcquireResource() wxOVERRIDE
@@ -2443,7 +2482,7 @@ protected:
     }
 
 private:
-    const wxBitmap m_sourceBitmap;
+    wxBitmap m_sourceBitmap;
 };
 
 //-----------------------------------------------------------------------------
@@ -2456,10 +2495,15 @@ public:
     typedef wxD2DBitmapResourceHolder NativeType;
 
     wxD2DBitmapData(wxGraphicsRenderer* renderer, const wxBitmap& bitmap) :
-        wxGraphicsBitmapData(renderer), m_bitmapHolder(bitmap) {}
+        wxGraphicsBitmapData(renderer)
+    {
+        m_bitmapHolder = new NativeType(bitmap);
+    }
 
-    wxD2DBitmapData(wxGraphicsRenderer* renderer, const void* pseudoNativeBitmap) :
-        wxGraphicsBitmapData(renderer), m_bitmapHolder(*static_cast<const NativeType*>(pseudoNativeBitmap)) {}
+    wxD2DBitmapData(wxGraphicsRenderer* renderer, NativeType* pseudoNativeBitmap) :
+        wxGraphicsBitmapData(renderer), m_bitmapHolder(pseudoNativeBitmap) {}
+
+    ~wxD2DBitmapData();
 
     // returns the native representation
     void* GetNativeBitmap() const wxOVERRIDE;
@@ -2468,25 +2512,30 @@ public:
 
     wxD2DManagedObject* GetManagedObject() wxOVERRIDE
     {
-        return &m_bitmapHolder;
+        return m_bitmapHolder;
     }
 
 private:
-    NativeType m_bitmapHolder;
+    NativeType* m_bitmapHolder;
 };
 
 //-----------------------------------------------------------------------------
 // wxD2DBitmapData implementation
 //-----------------------------------------------------------------------------
 
+wxD2DBitmapData::~wxD2DBitmapData()
+{
+    delete m_bitmapHolder;
+}
+
 void* wxD2DBitmapData::GetNativeBitmap() const
 {
-    return (void*)&m_bitmapHolder;
+    return static_cast<void*>(m_bitmapHolder);
 }
 
 wxCOMPtr<ID2D1Bitmap> wxD2DBitmapData::GetD2DBitmap()
 {
-    return m_bitmapHolder.GetD2DResource();
+    return m_bitmapHolder->GetD2DResource();
 }
 
 wxD2DBitmapData* wxGetD2DBitmapData(const wxGraphicsBitmap& bitmap)
@@ -4490,11 +4539,12 @@ void wxD2DContext::DrawBitmap(const wxGraphicsBitmap& bmp, wxDouble x, wxDouble
 
     wxD2DBitmapData* bitmapData = wxGetD2DBitmapData(bmp);
     bitmapData->Bind(this);
-    wxBitmap const& bitmap = static_cast<wxD2DBitmapData::NativeType*>(bitmapData->GetNativeBitmap())->GetSourceBitmap();
 
+    wxCOMPtr<ID2D1Bitmap> d2dBmp = bitmapData->GetD2DBitmap();
+    D2D1_SIZE_F d2dBmpSize = d2dBmp->GetSize();
     m_renderTargetHolder->DrawBitmap(
-        bitmapData->GetD2DBitmap(),
-        D2D1::RectF(0, 0, bitmap.GetWidth(), bitmap.GetHeight()),
+        d2dBmp,
+        D2D1::RectF(0, 0, d2dBmpSize.width, d2dBmpSize.height),
         D2D1::RectF(x, y, x + w, y + h),
         GetInterpolationQuality(),
         GetCompositionMode());
@@ -5127,7 +5177,7 @@ wxGraphicsBitmap wxD2DRenderer::CreateBitmap(const wxBitmap& bitmap)
 // create a graphics bitmap from a native bitmap
 wxGraphicsBitmap wxD2DRenderer::CreateBitmapFromNativeBitmap(void* bitmap)
 {
-    wxD2DBitmapData* bitmapData = new wxD2DBitmapData(this, bitmap);
+    wxD2DBitmapData* bitmapData = new wxD2DBitmapData(this, static_cast<wxD2DBitmapResourceHolder*>(bitmap));
 
     wxGraphicsBitmap graphicsBitmap;
     graphicsBitmap.SetRefData(bitmapData);
@@ -5144,7 +5194,7 @@ wxGraphicsBitmap wxD2DRenderer::CreateBitmapFromImage(const wxImage& image)
 wxImage wxD2DRenderer::CreateImageFromBitmap(const wxGraphicsBitmap& bmp)
 {
     return static_cast<wxD2DBitmapData::NativeType*>(bmp.GetNativeBitmap())
-        ->GetSourceBitmap().ConvertToImage();
+        ->ConvertToImage();
 }
 #endif
 
@@ -5192,8 +5242,11 @@ wxGraphicsFont wxD2DRenderer::CreateFontAtDPI(const wxFont& font,
 wxGraphicsBitmap wxD2DRenderer::CreateSubBitmap(const wxGraphicsBitmap& bitmap, wxDouble x, wxDouble y, wxDouble w, wxDouble h)
 {
     typedef wxD2DBitmapData::NativeType* NativeBitmap;
-    wxBitmap sourceBitmap = static_cast<NativeBitmap>(bitmap.GetNativeBitmap())->GetSourceBitmap();
-    return CreateBitmap(sourceBitmap.GetSubBitmap(wxRect(x, y, w, h)));
+
+    NativeBitmap natBmp = static_cast<NativeBitmap>(bitmap.GetNativeBitmap())->GetSubBitmap(x, y, w, h);
+    wxGraphicsBitmap bmpRes;
+    bmpRes.SetRefData(new wxD2DBitmapData(this, natBmp));
+    return bmpRes;
 }
 
 wxString wxD2DRenderer::GetName() const