Protect all LogicalFontInstance constructors

This way LogicalFontInstance can just be constructed by a
PhysicalFontFace based factory.

The patch also drops the wrong "Java logical font" comment
added by commit 125cdf3404e60cf78f2a5547e9a06ce994df5c8e.

Change-Id: Ibd5d7da0c3a65dbfa2c8ae6b05cf616d39b749f2
Reviewed-on: https://gerrit.libreoffice.org/46475
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>

6 files changed, 44 insertions, 51 deletions

diff --git a/vcl/inc/PhysicalFontFace.hxx b/vcl/inc/PhysicalFontFace.hxx
index 94d7eb5ebc44..ff708b99cfb8 100644
--- a/vcl/inc/PhysicalFontFace.hxx
+++ b/vcl/inc/PhysicalFontFace.hxx
@@ -46,33 +46,18 @@ public:
 // TODO: get rid of height/width for scalable fonts
 // TODO: make cloning cheaper
 
-// abstract base class for physical font faces
-
-// Note about physical and logical fonts:
-//
-// A physical font is a concept we have taken from the Java world
-//
-// From https://docs.oracle.com/javase/tutorial/2d/text/fonts.html
-//
-//      There are two types of fonts: physical fonts and logical fonts.
-//      Physical fonts are the actual font libraries consisting of, for
-//      example, TrueType or PostScript Type 1 fonts. The physical fonts
-//      may be Time, Helvetica, Courier, or any number of other fonts,
-//      including international fonts. Logical fonts are the following
-//      five font families: Serif, SansSerif, Monospaced, Dialog, and
-//      DialogInput. These logical fonts are not actual font libraries.
-//      Instead, the logical font names are mapped to physical fonts by
-//      the Java runtime environment.
-
+/**
+ * abstract base class for physical font faces
+ *
+ * It acts as a factory for its corresponding LogicalFontInstances and
+ * can be extended to cache device and font instance specific data.
+ */
 class VCL_PLUGIN_PUBLIC PhysicalFontFace : public FontAttributes
 {
 public:
     virtual                ~PhysicalFontFace() {}
 
-    // by using an PhysicalFontFace object as a factory for its corresponding
-    // LogicalFontInstance can be extended to cache device and font instance
-    // specific data
-    virtual LogicalFontInstance*  CreateFontInstance( const FontSelectPattern& ) const = 0;
+    virtual LogicalFontInstance* CreateFontInstance(const FontSelectPattern&) const;
     virtual PhysicalFontFace* Clone() const = 0;
 
     int                     GetHeight() const           { return mnHeight; }
@@ -84,7 +69,7 @@ public:
     sal_Int32               CompareIgnoreSize( const PhysicalFontFace& ) const;
 
 protected:
-    explicit                PhysicalFontFace( const FontAttributes& );
+    explicit PhysicalFontFace(const FontAttributes&);
     void                    SetBitmapSize( int nW, int nH ) { mnWidth=nW; mnHeight=nH; }
 
     long                    mnWidth;    // Width (in pixels)
diff --git a/vcl/inc/fontinstance.hxx b/vcl/inc/fontinstance.hxx
index 0158e972a990..7595c79036cd 100644
--- a/vcl/inc/fontinstance.hxx
+++ b/vcl/inc/fontinstance.hxx
@@ -22,21 +22,24 @@
 
 #include "fontselect.hxx"
 #include "impfontmetricdata.hxx"
+#include "PhysicalFontFace.hxx"
 
 #include <unordered_map>
 
-class ImplFontCache;
 class ConvertChar;
+class ImplFontCache;
 
 // TODO: allow sharing of metrics for related fonts
 
 class VCL_PLUGIN_PUBLIC LogicalFontInstance
 {
-public:
-    explicit        LogicalFontInstance( const FontSelectPattern& );
-    virtual         ~LogicalFontInstance();
+    // just declaring the factory function doesn't work AKA
+    // friend LogicalFontInstance* PhysicalFontFace::CreateFontInstance(const FontSelectPattern&) const;
+    friend class PhysicalFontFace;
 
 public: // TODO: make data members private
+    virtual ~LogicalFontInstance();
+
     ImplFontCache * mpFontCache;
     FontSelectPattern  maFontSelData;       // FontSelectionData
     ImplFontMetricDataRef mxFontMetric;        // Font attributes
@@ -52,6 +55,9 @@ public: // TODO: make data members private
     bool            GetFallbackForUnicode( sal_UCS4, FontWeight eWeight, OUString* pFontName ) const;
     void            IgnoreFallbackForUnicode( sal_UCS4, FontWeight eWeight, const OUString& rFontName );
 
+protected:
+    explicit LogicalFontInstance(const FontSelectPattern&);
+
 private:
     // cache of Unicode characters and replacement font names
     // TODO: a fallback map can be shared with many other ImplFontEntries
diff --git a/vcl/inc/quartz/salgdi.h b/vcl/inc/quartz/salgdi.h
index 5a346b6a2098..17faec998c26 100644
--- a/vcl/inc/quartz/salgdi.h
+++ b/vcl/inc/quartz/salgdi.h
@@ -63,7 +63,6 @@ public:
     virtual                         ~CoreTextFontFace() override;
 
     PhysicalFontFace*               Clone() const override;
-    LogicalFontInstance*            CreateFontInstance( const FontSelectPattern& ) const override;
     sal_IntPtr                      GetFontId() const override;
 
     int                             GetFontTable( const char pTagName[5], unsigned char* ) const;
diff --git a/vcl/inc/unx/freetype_glyphcache.hxx b/vcl/inc/unx/freetype_glyphcache.hxx
index a01992fa60c8..eb825b7c3f26 100644
--- a/vcl/inc/unx/freetype_glyphcache.hxx
+++ b/vcl/inc/unx/freetype_glyphcache.hxx
@@ -22,6 +22,7 @@
 
 #include <unx/glyphcache.hxx>
 #include <PhysicalFontFace.hxx>
+#include <fontinstance.hxx>
 
 // FreetypeFontFile has the responsibility that a font file is only mapped once.
 // (#86621#) the old directly ft-managed solution caused it to be mapped
@@ -118,6 +119,22 @@ public:
     virtual sal_IntPtr      GetFontId() const override { return mpFreetypeFontInfo->GetFontId(); }
 };
 
+// a class for cache entries for physical font instances that are based on serverfonts
+class VCL_DLLPUBLIC FreetypeFontInstance : public LogicalFontInstance
+{
+    friend LogicalFontInstance* FreetypeFontFace::CreateFontInstance(const FontSelectPattern&) const;
+
+    FreetypeFont* mpFreetypeFont;
+
+protected:
+    explicit FreetypeFontInstance(const FontSelectPattern&);
+
+public:
+    virtual ~FreetypeFontInstance() override;
+
+    void SetFreetypeFont(FreetypeFont* p);
+};
+
 #endif // INCLUDED_VCL_GENERIC_GLYPHS_GCACH_FTYP_HXX
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/vcl/inc/unx/glyphcache.hxx b/vcl/inc/unx/glyphcache.hxx
index c512628862fa..42b2f4244450 100644
--- a/vcl/inc/unx/glyphcache.hxx
+++ b/vcl/inc/unx/glyphcache.hxx
@@ -30,9 +30,9 @@
 #include <vcl/dllapi.h>
 #include <vcl/metric.hxx>
 
-#include <fontinstance.hxx>
 #include <sallayout.hxx>
 #include <fontattributes.hxx>
+#include <fontselect.hxx>
 #include <impfontmetricdata.hxx>
 #include <hb-ot.h>
 
@@ -194,19 +194,6 @@ private:
     hb_font_t*              mpHbFont;
 };
 
-// a class for cache entries for physical font instances that are based on serverfonts
-class VCL_DLLPUBLIC FreetypeFontInstance : public LogicalFontInstance
-{
-public:
-                            FreetypeFontInstance( FontSelectPattern const & );
-    virtual                 ~FreetypeFontInstance() override;
-
-    void                    SetFreetypeFont(FreetypeFont* p);
-
-private:
-    FreetypeFont*           mpFreetypeFont;
-};
-
 #endif // INCLUDED_VCL_INC_GENERIC_GLYPHCACHE_HXX
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/vcl/inc/win/winlayout.hxx b/vcl/inc/win/winlayout.hxx
index af9eaef473e1..4e1174899d8e 100644
--- a/vcl/inc/win/winlayout.hxx
+++ b/vcl/inc/win/winlayout.hxx
@@ -145,21 +145,20 @@ public:
 // win32 specific physical font instance
 class WinFontInstance : public LogicalFontInstance
 {
+    friend LogicalFontInstance* WinFontFace::CreateFontInstance(const FontSelectPattern&) const;
+
 public:
-    explicit                WinFontInstance( FontSelectPattern const & );
     virtual                 ~WinFontInstance() override;
 
-private:
-    // TODO: also add HFONT??? Watch out for issues with too many active fonts...
-
-    GlyphCache maGlyphCache;
 public:
     bool CacheGlyphToAtlas(HDC hDC, HFONT hFont, int nGlyphIndex, SalGraphics& rGraphics);
+    GlyphCache& GetGlyphCache() { return maGlyphCache; }
 
-    GlyphCache& GetGlyphCache()
-    {
-        return maGlyphCache;
-    }
+private:
+    explicit WinFontInstance(const FontSelectPattern&);
+
+    // TODO: also add HFONT??? Watch out for issues with too many active fonts...
+    GlyphCache maGlyphCache;
 };
 
 class TextOutRenderer