Merge pull request #2345 from Kozea/small-caps

Handle small-caps synthesis

docs/api_reference.rst

@@ -361,10 +361,6 @@ WeasyPrint does **not** support the ``@font-feature-values`` rule and the
 values of ``font-variant-alternates`` other than ``normal`` and
 ``historical-forms``.
 
-The ``font-variant-caps`` property is supported but needs the small-caps variant of
-the font to be installed. WeasyPrint does **not** simulate missing small-caps
-fonts.
-
 From `CSS Fonts Module Level 4`_ we only support the
 ``font-variation-settings`` property enabling specific font variations.
 

tests/draw/test_text.py

@@ -1012,3 +1012,140 @@ def test_huge_justification(assert_pixels):
         }
       </style>
       A B''')
+
+
+def test_font_variant_caps_small(assert_pixels):
+    assert_pixels('''
+        ________
+        _BB_BB__
+        _BB_B_B_
+        _B__BB__
+        _B__B___
+        ________
+    ''', '''
+      <style>
+        @page {size: 8px 6px}
+        p {
+          color: blue;
+          font-variant-caps: small-caps;
+          font-family: %s;
+          font-size: 6px;
+          line-height: 1;
+        }
+      </style>
+      <p>Pp</p>
+    ''' % SANS_FONTS)
+
+
+def test_font_variant_caps_all_small(assert_pixels):
+    assert_pixels('''
+        ________
+        BB_BB___
+        B_BB_B__
+        BB_BB___
+        B__B____
+        ________
+    ''', '''
+      <style>
+        @page {size: 8px 6px}
+        p {
+          color: blue;
+          font-variant-caps: all-small-caps;
+          font-family: %s;
+          font-size: 6px;
+          line-height: 1;
+        }
+      </style>
+      <p>Pp</p>
+    ''' % SANS_FONTS)
+
+
+def test_font_variant_caps_petite(assert_pixels):
+    assert_pixels('''
+        ________
+        _BB_BB__
+        _BB_B_B_
+        _B__BB__
+        _B__B___
+        ________
+    ''', '''
+      <style>
+        @page {size: 8px 6px}
+        p {
+          color: blue;
+          font-variant-caps: petite-caps;
+          font-family: %s;
+          font-size: 6px;
+          line-height: 1;
+        }
+      </style>
+      <p>Pp</p>
+    ''' % SANS_FONTS)
+
+
+def test_font_variant_caps_all_petite(assert_pixels):
+    assert_pixels('''
+        ________
+        BB_BB___
+        B_BB_B__
+        BB_BB___
+        B__B____
+        ________
+    ''', '''
+      <style>
+        @page {size: 8px 6px}
+        p {
+          color: blue;
+          font-variant-caps: all-petite-caps;
+          font-family: %s;
+          font-size: 6px;
+          line-height: 1;
+        }
+      </style>
+      <p>Pp</p>
+    ''' % SANS_FONTS)
+
+
+def test_font_variant_caps_unicase(assert_pixels):
+    assert_pixels('''
+        ________
+        BB______
+        B_B_BB__
+        BB__B_B_
+        B___BB__
+        ____B___
+    ''', '''
+      <style>
+        @page {size: 8px 6px}
+        p {
+          color: blue;
+          font-variant-caps: unicase;
+          font-family: %s;
+          font-size: 6px;
+          line-height: 1;
+        }
+      </style>
+      <p>Pp</p>
+    ''' % SANS_FONTS)
+
+
+def test_font_variant_caps_titling(assert_pixels):
+    assert_pixels('''
+        _BB_____
+        _BB_____
+        _BB__BB_
+        _B___B_B
+        _____BB_
+        _____B__
+    ''', '''
+      <style>
+        @page {size: 8px 6px}
+        p {
+          color: blue;
+          font-family: %s;
+          font-size: 6px;
+          line-height: 1;
+        }
+      </style>
+      <p>Pp</p>
+    ''' % SANS_FONTS)

weasyprint/css/validation/expanders.py

@@ -16,8 +16,8 @@
     background_size, block_ellipsis, border_image_source, border_image_slice,
     border_image_width, border_image_outset, border_image_repeat, border_style,
     border_width, box, column_count, column_width, flex_basis, flex_direction,
-    flex_grow_shrink, flex_wrap, font_family, font_size, font_stretch,
-    font_style, font_weight, gap, grid_line, grid_template, line_height,
+    flex_grow_shrink, flex_wrap, font_family, font_size, font_stretch, font_style,
+    font_variant_caps, font_weight, gap, grid_line, grid_template, line_height,
     list_style_image, list_style_position, list_style_type, mask_border_mode,
     other_colors, overflow_wrap, text_decoration_thickness, validate_non_shorthand)
 
@@ -678,7 +678,7 @@ def expand_font(tokens, name):
 
         if font_style([token]) is not None:
             suffix = '-style'
-        elif get_keyword(token) in ('normal', 'small-caps'):
+        elif font_variant_caps([token]) is not None:
             suffix = '-variant-caps'
         elif font_weight([token]) is not None:
             suffix = '-weight'

weasyprint/css/validation/properties.py

@@ -889,7 +889,7 @@ def font_feature_settings_list(tokens):
 @single_keyword
 def font_variant_alternates(keyword):
     # TODO: support other values
-    # See https://www.w3.org/TR/css-fonts-3/#font-variant-caps-prop
+    # See https://drafts.csswg.org/css-fonts/#font-variant-alternates-prop
     return keyword in ('normal', 'historical-forms')
 
 

weasyprint/draw/text.py

@@ -89,8 +89,7 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, matrix):
     if not textbox.text.strip():
         return []
 
-    font_size = textbox.style['font_size']
-    if font_size < 1e-6:  # default float precision used by pydyf
+    if textbox.style['font_size'] < 1e-6:  # default float precision used by pydyf
         return []
 
     pango.pango_layout_set_single_paragraph_mode(textbox.pango_layout.layout, True)
@@ -137,7 +136,7 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, matrix):
     utf8_text = textbox.pango_layout.text.encode()
     previous_utf8_position = 0
     stream.set_text_matrix(*matrix.values)
-    last_font = None
+    previous_pango_font = None
     string = ''
     x_advance = 0
     emojis = []
@@ -152,21 +151,21 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, matrix):
         offset = glyph_item.item.offset
         clusters = glyph_string.log_clusters
 
-        # Add font file content.
-        pango_font = glyph_item.item.analysis.font
-        font = stream.add_font(pango_font)
-
         # Get positions of the glyphs in the UTF-8 string.
         utf8_positions = [offset + clusters[i] for i in range(1, num_glyphs)]
         utf8_positions.append(offset + glyph_item.item.length)
 
-        # Go through the run glyphs.
-        if font != last_font:
+        pango_font = glyph_item.item.analysis.font
+        if pango_font != previous_pango_font:
+            # Add font file content and get font size.
+            previous_pango_font = pango_font
+            font, font_size = stream.add_font(pango_font)
+
+            # Go through the run glyphs.
             if string:
                 stream.show_text(string)
             string = ''
             stream.set_font_size(font.hash, 1 if font.bitmap else font_size)
-            last_font = font
         string += '<'
         for i in range(num_glyphs):
             glyph_info = glyphs[i]

weasyprint/pdf/anchors.py

@@ -203,7 +203,7 @@ def add_forms(forms, matrix, pdf, page, resources, stream, font_map):
             font_description = get_font_description(style)
             font = pango.pango_font_map_load_font(
                 font_map, context, font_description)
-            font = stream.add_font(font)
+            font, _ = stream.add_font(font)
             font.used_in_forms = True
 
             field_stream.set_font_size(font.hash, font_size)
@@ -252,7 +252,7 @@ def add_forms(forms, matrix, pdf, page, resources, stream, font_map):
             font_description = get_font_description(style)
             font = pango.pango_font_map_load_font(
                 font_map, context, font_description)
-            font = stream.add_font(font)
+            font, _ = stream.add_font(font)
             font.used_in_forms = True
 
             field_stream.set_font_size(font.hash, font_size)

weasyprint/pdf/fonts.py

@@ -17,39 +17,38 @@
 
 
 class Font:
-    def __init__(self, pango_font):
+    def __init__(self, pango_font, description, font_size):
         self.hb_font = pango.pango_font_get_hb_font(pango_font)
         self.hb_face = get_pango_font_hb_face(pango_font)
         self.file_content = get_hb_object_data(self.hb_face)
         self.index = harfbuzz.hb_face_get_index(self.hb_face)
 
-        pango_metrics = pango.pango_font_get_metrics(pango_font, ffi.NULL)
-        self.description = description = ffi.gc(
-            pango.pango_font_describe(pango_font), pango.pango_font_description_free)
-        self.font_size = pango.pango_font_description_get_size(description)
+        self.font_size = font_size
         self.style = pango.pango_font_description_get_style(description)
         self.family = ffi.string(pango.pango_font_description_get_family(description))
 
         self.variations = {}
-        variations = pango.pango_font_description_get_variations(self.description)
+        variations = pango.pango_font_description_get_variations(description)
         if variations != ffi.NULL:
             self.variations = {
                 part.split('=')[0]: float(part.split('=')[1])
                 for part in ffi.string(variations).decode().split(',')}
         if weight := self.variations.get('weight'):
-            pango.pango_font_description_set_weight(
-                self.description, int(round(weight)))
+            self.weight = int(round(weight))
+            pango.pango_font_description_set_weight(description, weight)
+        else:
+            self.weight = pango.pango_font_description_get_weight(description)
         if self.variations.get('ital'):
             pango.pango_font_description_set_style(
-                self.description, pango.PANGO_STYLE_ITALIC)
+                description, pango.PANGO_STYLE_ITALIC)
         elif self.variations.get('slnt'):
             pango.pango_font_description_set_style(
-                self.description, pango.PANGO_STYLE_OBLIQUE)
+                description, pango.PANGO_STYLE_OBLIQUE)
         if (width := self.variations.get('wdth')) is not None:
             stretch = min(
                 PANGO_STRETCH_PERCENT.items(),
                 key=lambda item: abs(item[0] - width))[1]
-            pango.pango_font_description_set_stretch(self.description, stretch)
+            pango.pango_font_description_set_stretch(description, stretch)
         description_string = ffi.string(
             pango.pango_font_description_to_string(description))
 
@@ -70,6 +69,7 @@ def __init__(self, pango_font):
 
         # Set ascent and descent.
         if self.font_size:
+            pango_metrics = pango.pango_font_get_metrics(pango_font, ffi.NULL)
             self.ascent = int(
                 pango.pango_font_metrics_get_ascent(pango_metrics) /
                 self.font_size * 1000)
@@ -126,9 +126,7 @@ def clean(self, cmap, hinting):
             full_font = io.BytesIO(self.file_content)
             ttfont = TTFont(full_font, fontNumber=self.index)
             if 'wght' not in self.variations:
-                weight = pango.pango_font_description_get_weight(
-                    self.description)
-                self.variations['wght'] = weight
+                self.variations['wght'] = self.weight
             if 'opsz' not in self.variations:
                 self.variations['opsz'] = self.font_size * FROM_UNITS
             if 'slnt' not in self.variations:

weasyprint/pdf/stream.py

@@ -161,10 +161,10 @@ def set_blend_mode(self, mode):
         }))
 
     def add_font(self, pango_font):
-        key = get_pango_font_key(pango_font)
+        key, description, font_size = get_pango_font_key(pango_font)
         if key not in self._fonts:
-            self._fonts[key] = Font(pango_font)
-        return self._fonts[key]
+            self._fonts[key] = Font(pango_font, description, font_size)
+        return self._fonts[key], font_size
 
     def add_group(self, x, y, width, height):
         resources = pydyf.Dictionary({

weasyprint/text/constants.py

@@ -38,6 +38,16 @@
     'WRAP_CHAR': pango.PANGO_WRAP_CHAR,
     'WRAP_WORD_CHAR': pango.PANGO_WRAP_WORD_CHAR
 }
+# Some variants have been added in Pango 1.50 and are ignored when used.
+PANGO_VARIANT = {
+    'normal': pango.PANGO_VARIANT_NORMAL,
+    'small-caps': pango.PANGO_VARIANT_SMALL_CAPS,
+    'all-small-caps': pango.PANGO_VARIANT_ALL_SMALL_CAPS,
+    'petite-caps': pango.PANGO_VARIANT_PETITE_CAPS,
+    'all-petite-caps': pango.PANGO_VARIANT_ALL_PETITE_CAPS,
+    'unicase': pango.PANGO_VARIANT_UNICASE,
+    'titling-caps': pango.PANGO_VARIANT_TITLE_CAPS,
+}
 
 # Language system tags
 # From https://docs.microsoft.com/typography/opentype/spec/languagetags

weasyprint/text/ffi.py

@@ -145,6 +145,16 @@
         PANGO_WRAP_WORD_CHAR
     } PangoWrapMode;
 
+    typedef enum {
+        PANGO_VARIANT_NORMAL,
+        PANGO_VARIANT_SMALL_CAPS,
+        PANGO_VARIANT_ALL_SMALL_CAPS,
+        PANGO_VARIANT_PETITE_CAPS,
+        PANGO_VARIANT_ALL_PETITE_CAPS,
+        PANGO_VARIANT_UNICASE,
+        PANGO_VARIANT_TITLE_CAPS,
+    } PangoVariant;
+
     typedef enum {
         PANGO_TAB_LEFT
     } PangoTabAlign;
@@ -291,6 +301,8 @@
         PangoFontDescription *desc, double size);
     void pango_font_description_set_variations (
         PangoFontDescription* desc, const char* variations);
+    void pango_font_description_set_variant (
+        PangoFontDescription* desc, PangoVariant variant);
 
     PangoStyle pango_font_description_get_style (const PangoFontDescription *desc);
     const char* pango_font_description_get_variations (