Merge branch 'gc-print-font-scale'

Fix size of text drawing using wxGraphicsContext when printing in wxMSW.

See https://github.com/wxWidgets/wxWidgets/pull/1214

src/msw/graphics.cpp

@@ -336,6 +336,14 @@ public:
                       REAL size,
                       int style,
                       const wxColour& col);
+
+    // This ctor takes ownership of the brush.
+    wxGDIPlusFontData(wxGraphicsRenderer* renderer,
+                      const wxString& name,
+                      REAL size,
+                      int style,
+                      Brush* textBrush);
+
     ~wxGDIPlusFontData();
 
     virtual Brush* GetGDIPlusBrush() { return m_textBrush; }
@@ -347,7 +355,16 @@ private :
     void Init(const wxString& name,
               REAL size,
               int style,
-              const wxColour& col);
+              Brush* textBrush);
+
+    // Common part of ctors taking wxColour.
+    void Init(const wxString& name,
+              REAL size,
+              int style,
+              const wxColour& col)
+    {
+        Init(name, size, style, new SolidBrush(wxColourToColor(col)));
+    }
 
     Brush* m_textBrush;
     Font* m_font;
@@ -432,9 +449,6 @@ public:
     Graphics* GetGraphics() const { return m_context; }
 
 protected:
-
-    wxDouble m_fontScaleRatio;
-
     // Used from ctors (including those in the derived classes) and takes
     // ownership of the graphics pointer that must be non-NULL.
     void Init(Graphics* graphics, int width, int height);
@@ -507,8 +521,41 @@ class wxGDIPlusPrintingContext : public wxGDIPlusContext
 {
 public:
     wxGDIPlusPrintingContext( wxGraphicsRenderer* renderer, const wxDC& dc );
-    virtual ~wxGDIPlusPrintingContext() { }
+
-protected:
+    // Override to scale the font proportionally to the DPI.
+    virtual void SetFont(const wxGraphicsFont& font) wxOVERRIDE
+    {
+        // The casts here are safe because we're only supposed to be passed
+        // fonts created by this renderer.
+        Font* const f = static_cast<wxGDIPlusFontData*>(font.GetRefData())->GetGDIPlusFont();
+        Brush* const b = static_cast<wxGDIPlusFontData*>(font.GetRefData())->GetGDIPlusBrush();
+
+        // To scale the font, we need to create a new one which means
+        // retrieving all the parameters originally used to create the font.
+        FontFamily ffamily;
+        f->GetFamily(&ffamily);
+
+        WCHAR familyName[LF_FACESIZE];
+        ffamily.GetFamilyName(familyName);
+
+        wxGraphicsFont fontScaled;
+        fontScaled.SetRefData(new wxGDIPlusFontData
+                                  (
+                                    GetRenderer(),
+                                    familyName,
+                                    f->GetSize() / m_fontScaleRatio,
+                                    f->GetStyle(),
+                                    b->Clone()
+                                  ));
+        wxGDIPlusContext::SetFont(fontScaled);
+    }
+
+private:
+    // This is logically const ratio between this context DPI and the standard
+    // one which is used for scaling the fonts used with this context: without
+    // this, the fonts wouldn't have the correct size, even though we
+    // explicitly create them using UnitPoint units.
+    wxDouble m_fontScaleRatio;
 };
 
 //-----------------------------------------------------------------------------
@@ -983,7 +1030,7 @@ void
 wxGDIPlusFontData::Init(const wxString& name,
                         REAL size,
                         int style,
-                        const wxColour& col)
+                        Brush* textBrush)
 {
 #if wxUSE_PRIVATE_FONTS
     // If the user has registered any private fonts, they should be used in
@@ -1015,7 +1062,7 @@ wxGDIPlusFontData::Init(const wxString& name,
         m_font = new Font(name.wc_str(), size, style, UnitPoint);
     }
 
-    m_textBrush = new SolidBrush(wxColourToColor(col));
+    m_textBrush = textBrush;
 }
 
 wxGDIPlusFontData::wxGDIPlusFontData( wxGraphicsRenderer* renderer,
@@ -1046,6 +1093,16 @@ wxGDIPlusFontData::wxGDIPlusFontData(wxGraphicsRenderer* renderer,
     Init(name, size, style, col);
 }
 
+wxGDIPlusFontData::wxGDIPlusFontData(wxGraphicsRenderer* renderer,
+                                     const wxString& name,
+                                     REAL size,
+                                     int style,
+                                     Brush* brush)
+    : wxGraphicsObjectRefData(renderer)
+{
+    Init(name, size, style, brush);
+}
+
 wxGDIPlusFontData::~wxGDIPlusFontData()
 {
     delete m_textBrush;
@@ -1687,7 +1744,6 @@ void wxGDIPlusContext::Init(Graphics* graphics, int width, int height)
     m_state2 = 0;
     m_width = width;
     m_height = height;
-    m_fontScaleRatio = 1.0;
 
     m_context->SetTextRenderingHint(TextRenderingHintSystemDefault);
     m_context->SetPixelOffsetMode(PixelOffsetModeHalf);
@@ -2119,8 +2175,6 @@ void wxGDIPlusContext::GetTextExtent( const wxString &str, wxDouble *width, wxDo
         FontFamily ffamily ;
         f->GetFamily(&ffamily) ;
 
-        REAL factorY = m_fontScaleRatio;
-
         // Notice that we must use the real font style or the results would be
         // incorrect for italic/bold fonts.
         const INT style = f->GetStyle();
@@ -2131,11 +2185,11 @@ void wxGDIPlusContext::GetTextExtent( const wxString &str, wxDouble *width, wxDo
         REAL rHeight = ffamily.GetLineSpacing(style) * size / emHeight;
 
         if ( height && str.empty() )
-            *height = rHeight * factorY;
+            *height = rHeight;
         if ( descent )
-            *descent = rDescent * factorY;
+            *descent = rDescent;
         if ( externalLeading )
-            *externalLeading = (rHeight - rAscent - rDescent) * factorY;
+            *externalLeading = rHeight - rAscent - rDescent;
     }
 
     // measuring empty strings is not guaranteed, so do it by hand
@@ -2278,7 +2332,7 @@ wxGDIPlusPrintingContext::wxGDIPlusPrintingContext( wxGraphicsRenderer* renderer
 
     // We use this modifier when measuring fonts. It is needed because the
     // page scale is modified above.
-    m_fontScaleRatio = context->GetDpiY() / 72.0;
+    m_fontScaleRatio = context->GetDpiY() / 96.0;
 }
 
 //-----------------------------------------------------------------------------