Make PyFT2Font a subclass of FT2Font

Author: QuLogic

src/ft2font.cpp

@@ -207,15 +207,13 @@ FT2Font::get_path(std::vector<double> &vertices, std::vector<unsigned char> &cod
 }
 
 FT2Font::FT2Font(long hinting_factor_, std::vector<FT2Font *> &fallback_list,
-                 FT2Font::WarnFunc warn, bool warn_if_used)
-    : ft_glyph_warn(warn), warn_if_used(warn_if_used), image({1, 1}), face(nullptr),
+                 bool warn_if_used)
+    : warn_if_used(warn_if_used), image({1, 1}), face(nullptr), fallbacks(fallback_list),
       hinting_factor(hinting_factor_),
       // set default kerning factor to 0, i.e., no kerning manipulation
       kerning_factor(0)
 {
     clear();
-    // Set fallbacks
-    std::copy(fallback_list.begin(), fallback_list.end(), std::back_inserter(fallbacks));
 }
 
 FT2Font::~FT2Font()
@@ -234,7 +232,8 @@ void FT2Font::open(FT_Open_Args &open_args)
 void FT2Font::close()
 {
     // This should be idempotent, in case a user manually calls close before the
-    // destructor does.
+    // destructor does. Note for example, that PyFT2Font _does_ call this before the
+    // base destructor to ensure internal pointers are cleared early enough.
 
     for (auto & glyph : glyphs) {
         FT_Done_Glyph(glyph);
@@ -544,21 +543,19 @@ FT_UInt FT2Font::get_char_index(FT_ULong charcode, bool fallback = false)
     return FT_Get_Char_Index(ft_object->get_face(), charcode);
 }
 
-void FT2Font::get_width_height(long *width, long *height)
+std::tuple<long, long> FT2Font::get_width_height()
 {
-    *width = advance;
-    *height = bbox.yMax - bbox.yMin;
+    return {advance, bbox.yMax - bbox.yMin};
 }
 
 long FT2Font::get_descent()
 {
     return -bbox.yMin;
 }
 
-void FT2Font::get_bitmap_offset(long *x, long *y)
+std::tuple<long, long> FT2Font::get_bitmap_offset()
 {
-    *x = bbox.xMin;
-    *y = 0;
+    return {bbox.xMin, 0};
 }
 
 void FT2Font::draw_glyphs_to_bitmap(bool antialiased)
@@ -607,8 +604,11 @@ void FT2Font::draw_glyph_to_bitmap(
     draw_bitmap(im, &bitmap->bitmap, x + bitmap->left, y);
 }
 
-void FT2Font::get_glyph_name(unsigned int glyph_number, std::string &buffer)
+std::string FT2Font::get_glyph_name(unsigned int glyph_number)
 {
+    std::string buffer;
+    buffer.resize(128);
+
     if (!FT_HAS_GLYPH_NAMES(face)) {
         /* Note that this generated name must match the name that
            is generated by ttconv in ttfont_CharStrings_getname. */
@@ -625,6 +625,8 @@ void FT2Font::get_glyph_name(unsigned int glyph_number, std::string &buffer)
             buffer.resize(len);
         }
     }
+
+    return buffer;
 }
 
 long FT2Font::get_name_index(char *name)

src/ft2font.h

@@ -12,6 +12,7 @@
 #include <set>
 #include <string>
 #include <string_view>
+#include <tuple>
 #include <unordered_map>
 #include <vector>
 
@@ -96,11 +97,9 @@ extern FT_Library _ft2Library;
 
 class FT2Font
 {
-    typedef void (*WarnFunc)(FT_ULong charcode, std::set<FT_String*> family_names);
-
   public:
     FT2Font(long hinting_factor, std::vector<FT2Font *> &fallback_list,
-            WarnFunc warn, bool warn_if_used);
+            bool warn_if_used);
     virtual ~FT2Font();
     void open(FT_Open_Args &open_args);
     void close();
@@ -124,14 +123,14 @@ class FT2Font
                                  std::set<FT_String*> &glyph_seen_fonts,
                                  bool override);
     void load_glyph(FT_UInt glyph_index, FT_Int32 flags);
-    void get_width_height(long *width, long *height);
-    void get_bitmap_offset(long *x, long *y);
+    std::tuple<long, long> get_width_height();
+    std::tuple<long, long> get_bitmap_offset();
     long get_descent();
     void draw_glyphs_to_bitmap(bool antialiased);
     void draw_glyph_to_bitmap(
         py::array_t<uint8_t, py::array::c_style> im,
         int x, int y, size_t glyphInd, bool antialiased);
-    void get_glyph_name(unsigned int glyph_number, std::string &buffer);
+    std::string get_glyph_name(unsigned int glyph_number);
     long get_name_index(char *name);
     FT_UInt get_char_index(FT_ULong charcode, bool fallback);
     void get_path(std::vector<double> &vertices, std::vector<unsigned char> &codes);
@@ -167,8 +166,9 @@ class FT2Font
         return FT_HAS_KERNING(face);
     }
 
+  protected:
+    virtual void ft_glyph_warn(FT_ULong charcode, std::set<FT_String*> family_names) = 0;
   private:
-    WarnFunc ft_glyph_warn;
     bool warn_if_used;
     py::array_t<uint8_t, py::array::c_style> image;
     FT_Face face;