python: expose new text.AbstractFont APIs.

And add a bounds check for glyph_advance() and the new glyph_size() too.

doc/python/magnum.text.rst

@@ -73,9 +73,17 @@
     :raise AssertionError: If no file is opened
 .. py:property:: magnum.text.AbstractFont.line_height
     :raise AssertionError: If no file is opened
+.. py:property:: magnum.text.AbstractFont.glyph_count
+    :raise AssertionError: If no file is opened
 .. py:function:: magnum.text.AbstractFont.glyph_id
     :raise AssertionError: If no file is opened
+.. py:function:: magnum.text.AbstractFont.glyph_size
+    :raise AssertionError: If no file is opened
+    :raise IndexError: If :p:`glyph` is negative or not less than
+        :ref:`glyph_count`
 .. py:function:: magnum.text.AbstractFont.glyph_advance
     :raise AssertionError: If no file is opened
+    :raise IndexError: If :p:`glyph` is negative or not less than
+        :ref:`glyph_count`
 .. py:function:: magnum.text.AbstractFont.fill_glyph_cache
     :raise AssertionError: If no file is opened

src/python/magnum/test/test_text.py

@@ -57,8 +57,12 @@ class Font(unittest.TestCase):
             font.descent
         with self.assertRaisesRegex(AssertionError, "no file opened"):
             font.line_height
+        with self.assertRaisesRegex(AssertionError, "no file opened"):
+            font.glyph_count
         with self.assertRaisesRegex(AssertionError, "no file opened"):
             font.glyph_id('A')
+        with self.assertRaisesRegex(AssertionError, "no file opened"):
+            font.glyph_size(0)
         with self.assertRaisesRegex(AssertionError, "no file opened"):
             font.glyph_advance(0)
         # fill_glyph_cache() not tested as it needs a GL context; assuming it's
@@ -88,7 +92,9 @@ class Font(unittest.TestCase):
         self.assertEqual(font.ascent, 17.011186599731445)
         self.assertEqual(font.descent, -4.322147846221924)
         self.assertEqual(font.line_height, 21.33333396911621)
+        self.assertEqual(font.glyph_count, 671)
         self.assertEqual(font.glyph_id('A'), 36)
+        self.assertEqual(font.glyph_size(36), (12.0, 14.0))
         self.assertEqual(font.glyph_advance(36), (11.7136, 0.0))
 
         # Deleting the font should decrease manager refcount again
@@ -102,3 +108,14 @@ class Font(unittest.TestCase):
             font.open_data(f.read(), 16.0)
 
         self.assertEqual(font.size, 16.0)
+
+    def test_glyph_oob(self):
+        font = text.FontManager().load_and_instantiate('StbTrueTypeFont')
+
+        font.open_file(os.path.join(os.path.dirname(__file__), 'Oxygen.ttf'), 16.0)
+        self.assertEqual(font.glyph_count, 671)
+
+        with self.assertRaises(IndexError):
+            font.glyph_size(671)
+        with self.assertRaises(IndexError):
+            font.glyph_advance(671)

src/python/magnum/text.cpp

@@ -60,6 +60,17 @@ template<class R, class Arg1, R(Text::AbstractFont::*f)(Arg1)> R checkOpened(Tex
     }
     return (self.*f)(arg1);
 }
+template<class R, R(Text::AbstractFont::*f)(UnsignedInt)> R checkOpenedBounds(Text::AbstractFont& self, UnsignedInt glyph) {
+    if(!self.isOpened()) {
+        PyErr_SetString(PyExc_AssertionError, "no file opened");
+        throw py::error_already_set{};
+    }
+    if(glyph >= self.glyphCount()) {
+        PyErr_SetNone(PyExc_IndexError);
+        throw py::error_already_set{};
+    }
+    return (self.*f)(glyph);
+}
 
 }
 
@@ -136,8 +147,10 @@ void text(py::module_& m) {
         .def_property_readonly("ascent", checkOpened<Float, &Text::AbstractFont::ascent>, "Font ascent")
         .def_property_readonly("descent", checkOpened<Float, &Text::AbstractFont::descent>, "Font descent")
         .def_property_readonly("line_height", checkOpened<Float, &Text::AbstractFont::lineHeight>, "Line height")
+        .def_property_readonly("glyph_count", checkOpened<UnsignedInt, &Text::AbstractFont::glyphCount>, "Total count of glyphs in the font")
         .def("glyph_id", checkOpened<UnsignedInt, char32_t, &Text::AbstractFont::glyphId>, "Glyph ID for given character", py::arg("character"))
-        .def("glyph_advance", checkOpened<Vector2, UnsignedInt, &Text::AbstractFont::glyphAdvance>, "Glyph advance", py::arg("glyph"))
+        .def("glyph_size", checkOpenedBounds<Vector2, &Text::AbstractFont::glyphSize>, "Glyph size in pixels", py::arg("glyph"))
+        .def("glyph_advance", checkOpenedBounds<Vector2, &Text::AbstractFont::glyphAdvance>, "Glyph advance in pixels", py::arg("glyph"))
         .def("fill_glyph_cache", [](Text::AbstractFont& self, Text::AbstractGlyphCache& cache, const std::string& characters) {
             if(!self.isOpened()) {
                 PyErr_SetString(PyExc_AssertionError, "no file opened");