Implement get_text_extents() and get_glyph_extents() of ScaledFont

ScaledFont::get_text_extents() and ScaledFont::get_glyph_extents()
were declared in the header but their implementations were missing.
Fixes #30

3 files changed, 48 insertions, 1 deletions

diff --git a/cairomm/scaledfont.cc b/cairomm/scaledfont.cc
index c9c6b99..4974e90 100644
--- a/cairomm/scaledfont.cc
+++ b/cairomm/scaledfont.cc
@@ -62,6 +62,18 @@ void ScaledFont::get_extents(FontExtents& extents) const
   check_object_status_and_throw_exception(*this);
 }
 
+void ScaledFont::get_text_extents(const std::string& utf8, TextExtents& extents) const
+{
+  cairo_scaled_font_text_extents(m_cobject, utf8.c_str(), static_cast<cairo_text_extents_t*>(&extents));
+  check_object_status_and_throw_exception(*this);
+}
+
+void ScaledFont::get_glyph_extents(const std::vector<Glyph>& glyphs, TextExtents& extents) const
+{
+  cairo_scaled_font_glyph_extents(m_cobject, glyphs.data(), glyphs.size(), static_cast<cairo_text_extents_t*>(&extents));
+  check_object_status_and_throw_exception(*this);
+}
+
 RefPtr<FontFace> ScaledFont::get_font_face() const
 {
   auto face = cairo_scaled_font_get_font_face(m_cobject);
diff --git a/cairomm/scaledfont.h b/cairomm/scaledfont.h
index 4f1ae3a..fa76bb0 100644
--- a/cairomm/scaledfont.h
+++ b/cairomm/scaledfont.h
@@ -137,7 +137,7 @@ public:
    *
    * @since 1.8
    **/
-  void get_glyph_extents(const std::vector<Glyph>& glyphs, TextExtents& extents);
+  void get_glyph_extents(const std::vector<Glyph>& glyphs, TextExtents& extents) const;
 
   /** The FontFace with which this ScaledFont was created.
    * @since 1.2
diff --git a/tests/test-scaled-font.cc b/tests/test-scaled-font.cc
index ff5f1a7..110c088 100644
--- a/tests/test-scaled-font.cc
+++ b/tests/test-scaled-font.cc
@@ -52,6 +52,41 @@ BOOST_AUTO_TEST_CASE(test_scale_matrix)
   // no real test, just excercising the functionality
 }
 
+BOOST_AUTO_TEST_CASE(test_get_text_extents)
+{
+  auto face = ToyFontFace::create("sans", ToyFontFace::Slant::NORMAL, ToyFontFace::Weight::NORMAL);
+  Matrix m;
+  cairo_matrix_init_scale(&m, 2.0, 4.0);
+  auto font = ScaledFont::create(face, m, m, FontOptions());
+  BOOST_REQUIRE(font);
+
+  TextExtents extents;
+  font->get_text_extents("sans", extents);
+
+  BOOST_CHECK_LE(0, extents.width);
+  BOOST_CHECK_LE(0, extents.height);
+}
+
+BOOST_AUTO_TEST_CASE(test_get_glyph_extents)
+{
+  auto face = ToyFontFace::create("sans", ToyFontFace::Slant::NORMAL, ToyFontFace::Weight::NORMAL);
+  Matrix m;
+  cairo_matrix_init_scale(&m, 2.0, 4.0);
+  auto font = ScaledFont::create(face, m, m, FontOptions());
+  BOOST_REQUIRE(font);
+
+  std::vector<Glyph> glyphs;
+  std::vector<TextCluster> clusters;
+  TextClusterFlags flags;
+  font->text_to_glyphs(0, 0, "sans", glyphs, clusters, flags);
+
+  TextExtents extents;
+  font->get_glyph_extents(glyphs, extents);
+
+  BOOST_CHECK_LE(0, extents.width);
+  BOOST_CHECK_LE(0, extents.height);
+}
+
 BOOST_AUTO_TEST_CASE(test_get_font_face)
 {
   // this is to test for a bug where we were accidentally freeing the resulting