Draw PNG and SVG emojis

weasyprint/document.py

@@ -16,7 +16,7 @@
 
 import pydyf
 from fontTools import subset
-from fontTools.ttLib import TTFont, TTLibError
+from fontTools.ttLib import TTFont, TTLibError, ttFont
 
 from . import CSS, Attachment, __version__
 from .css import get_all_computed_styles
@@ -30,7 +30,7 @@
 from .layout import LayoutContext, layout_document
 from .layout.percentages import percentage
 from .logger import LOGGER, PROGRESS_LOGGER
-from .text.ffi import ffi, pango
+from .text.ffi import ffi, harfbuzz, pango
 from .text.fonts import FontConfiguration
 from .urls import URLFetchingError
 
@@ -68,6 +68,8 @@ def _w3c_date_to_pdf(string, attr_name):
 class Font:
     def __init__(self, file_content, pango_font, index):
         pango_metrics = pango.pango_font_get_metrics(pango_font, ffi.NULL)
+        hb_font = pango.pango_font_get_hb_font(pango_font)
+        hb_face = harfbuzz.hb_font_get_face(hb_font)
         self._font_description = pango.pango_font_describe(pango_font)
         self.family = ffi.string(pango.pango_font_description_get_family(
             self._font_description))
@@ -93,6 +95,9 @@ def __init__(self, file_content, pango_font, index):
         self.descent = -int(
             pango.pango_font_metrics_get_descent(pango_metrics) /
             font_size * 1000)
+        self.upem = harfbuzz.hb_face_get_upem(hb_face)
+        self.png = harfbuzz.hb_ot_color_has_png(hb_face)
+        self.svg = harfbuzz.hb_ot_color_has_svg(hb_face)
         self.stemv = 80
         self.stemh = 80
         self.bbox = [0, 0, 0, 0]
@@ -1286,12 +1291,14 @@ def write_pdf(self, target=None, zoom=1, attachments=None, finisher=None):
                 fonts_by_file_hash[font.file_hash] = [font]
         font_references_by_file_hash = {}
         for file_hash, fonts in fonts_by_file_hash.items():
+            content = fonts[0].file_content
+
             if 'fonts' in self.optimize_size:
                 # Optimize font
                 cmap = {}
                 for font in fonts:
                     cmap = {**cmap, **font.cmap}
-                full_font = io.BytesIO(fonts[0].file_content)
+                full_font = io.BytesIO(content)
                 optimized_font = io.BytesIO()
                 try:
                     ttfont = TTFont(full_font, fontNumber=fonts[0].index)
@@ -1305,9 +1312,31 @@ def write_pdf(self, target=None, zoom=1, attachments=None, finisher=None):
                     content = optimized_font.getvalue()
                 except TTLibError:
                     LOGGER.warning('Unable to optimize font')
-                    content = fonts[0].file_content
-            else:
-                content = fonts[0].file_content
+
+            if fonts[0].png or fonts[0].svg:
+                # Add empty glyphs instead of PNG or SVG emojis
+                full_font = io.BytesIO(content)
+                try:
+                    ttfont = TTFont(full_font, fontNumber=fonts[0].index)
+                    if 'loca' not in ttfont or 'glyf' not in ttfont:
+                        ttfont['loca'] = ttFont.getTableClass('loca')()
+                        ttfont['glyf'] = ttFont.getTableClass('glyf')()
+                        ttfont['glyf'].glyphOrder = ttfont.getGlyphOrder()
+                        ttfont['glyf'].glyphs = {
+                            name: ttFont.getTableModule('glyf').Glyph()
+                            for name in ttfont['glyf'].glyphOrder}
+                    else:
+                        for glyph in ttfont['glyf'].glyphs:
+                            ttfont['glyf'][glyph] = (
+                                ttFont.getTableModule('glyf').Glyph())
+                    for table_name in ('CBDT', 'CBLC', 'SVG '):
+                        if table_name in ttfont:
+                            del ttfont[table_name]
+                    output_font = io.BytesIO()
+                    ttfont.save(output_font)
+                    content = output_font.getvalue()
+                except TTLibError:
+                    LOGGER.warning('Unable to save emoji font')
 
             # Include font
             font_type = 'otf' if content[:4] == b'OTTO' else 'ttf'

weasyprint/draw.py

@@ -9,10 +9,13 @@
 import contextlib
 import operator
 from colorsys import hsv_to_rgb, rgb_to_hsv
+from io import BytesIO
 from math import ceil, floor, pi, sqrt, tan
 
+from PIL import Image
+
 from .formatting_structure import boxes
-from .images import SVGImage
+from .images import RasterImage, SVGImage
 from .layout import replaced
 from .layout.backgrounds import BackgroundLayer
 from .stacking import StackingContext
@@ -982,9 +985,12 @@ def draw_text(stream, textbox, offset_x, text_overflow, block_ellipsis):
 
     textbox.pango_layout.reactivate(textbox.style)
     stream.begin_text()
-    draw_first_line(stream, textbox, text_overflow, block_ellipsis, x, y)
+    emojis = draw_first_line(
+        stream, textbox, text_overflow, block_ellipsis, x, y)
     stream.end_text()
 
+    draw_emojis(stream, textbox.style['font_size'], x, y, emojis)
+
     # Draw text decoration
     values = textbox.style['text_decoration_line']
     color = textbox.style['text_decoration_color']
@@ -1010,6 +1016,15 @@ def draw_text(stream, textbox, offset_x, text_overflow, block_ellipsis):
     textbox.pango_layout.deactivate()
 
 
+def draw_emojis(stream, font_size, x, y, emojis):
+    for emoji in emojis:
+        for image, font, a, d, e, f in emojis:
+            stream.push_state()
+            stream.transform(a=a, d=d, e=x + e * font_size, f=y + f)
+            image.draw(stream, font_size, font_size, None)
+            stream.pop_state()
+
+
 def draw_first_line(stream, textbox, text_overflow, block_ellipsis, x, y):
     """Draw the given ``textbox`` line to the document ``stream``."""
     pango.pango_layout_set_single_paragraph_mode(
@@ -1066,6 +1081,8 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, x, y):
     last_font = None
     string = ''
     fonts = stream.get_fonts()
+    x_advance = 0
+    emojis = []
     for run in runs:
         # Pango objects
         glyph_item = ffi.cast('PangoGlyphItem *', run.data)
@@ -1083,7 +1100,9 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, x, y):
         if font_hash in fonts:
             font = fonts[font_hash]
         else:
-            hb_blob = harfbuzz.hb_face_reference_blob(hb_face)
+            hb_blob = ffi.gc(
+                harfbuzz.hb_face_reference_blob(hb_face),
+                harfbuzz.hb_blob_destroy)
             hb_data = harfbuzz.hb_blob_get_data(hb_blob, stream.length)
             file_content = ffi.unpack(hb_data, int(stream.length[0]))
             index = harfbuzz.hb_face_get_index(hb_face)
@@ -1147,6 +1166,39 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, x, y):
                 font.cmap[glyph] = utf8_text[utf8_slice].decode('utf-8')
             previous_utf8_position = utf8_position
 
+            if font.svg:
+                hb_blob = ffi.gc(
+                    harfbuzz.hb_ot_color_glyph_reference_svg(hb_face, glyph),
+                    harfbuzz.hb_blob_destroy)
+                hb_data = harfbuzz.hb_blob_get_data(hb_blob, stream.length)
+                if hb_data != ffi.NULL:
+                    svg_data = ffi.unpack(hb_data, int(stream.length[0]))
+                    image = SVGImage(svg_data, None, None, stream)
+                    a = d = font.widths[glyph] / 1000 / font.upem * font_size
+                    emojis.append([image, font, a, d, x_advance, 0])
+            elif font.png:
+                hb_blob = ffi.gc(
+                    harfbuzz.hb_ot_color_glyph_reference_png(hb_font, glyph),
+                    harfbuzz.hb_blob_destroy)
+                hb_data = harfbuzz.hb_blob_get_data(hb_blob, stream.length)
+                if hb_data != ffi.NULL:
+                    png_data = ffi.unpack(hb_data, int(stream.length[0]))
+                    pillow_image = Image.open(BytesIO(png_data))
+                    image_id = f'{font.hash}{glyph}'
+                    image = RasterImage(
+                        pillow_image, image_id, optimize_size=())
+                    d = font.widths[glyph] / 1000
+                    a = pillow_image.width / pillow_image.height * d
+                    pango.pango_font_get_glyph_extents(
+                        pango_font, glyph, stream.ink_rect,
+                        stream.logical_rect)
+                    f = units_to_double(
+                        (-stream.logical_rect.y - stream.logical_rect.height))
+                    f = f / font_size - font_size
+                    emojis.append([image, font, a, d, x_advance, f])
+
+            x_advance += (font.widths[glyph] + offset) / 1000
+
         # Close the last glyphs list, remove if empty
         if string[-1] == '<':
             string = string[:-1]
@@ -1156,6 +1208,8 @@ def draw_first_line(stream, textbox, text_overflow, block_ellipsis, x, y):
     # Draw text
     stream.show_text(string)
 
+    return emojis
+
 
 def draw_wave(stream, x, y, width, offset_x, radius):
     up = 1

weasyprint/images.py

@@ -34,7 +34,8 @@ def from_exception(cls, exception):
 
 
 class RasterImage:
-    def __init__(self, pillow_image, optimize_size):
+    def __init__(self, pillow_image, image_id, optimize_size):
+        pillow_image.id = image_id
         self._pillow_image = pillow_image
         self._optimize_size = optimize_size
         self._intrinsic_width = pillow_image.width
@@ -131,8 +132,8 @@ def get_image_from_uri(cache, url_fetcher, optimize_size, url,
                             raster_exception)
                 else:
                     # Store image id to enable cache in Stream.add_image
-                    pillow_image.id = len(cache)
-                    image = RasterImage(pillow_image, optimize_size)
+                    image_id = len(cache)
+                    image = RasterImage(pillow_image, image_id, optimize_size)
 
     except (URLFetchingError, ImageLoadingError) as exception:
         LOGGER.error('Failed to load image at %r: %s', url, exception)

weasyprint/svg/images.py

@@ -22,9 +22,10 @@ def svg(svg, node, font_size):
             node.get('width'), node.get('height'), font_size)
     scale_x, scale_y, translate_x, translate_y = preserve_ratio(
         svg, node, font_size, width, height)
-    svg.stream.rectangle(0, 0, width, height)
-    svg.stream.clip()
-    svg.stream.end()
+    if svg.tree != node:
+        svg.stream.rectangle(0, 0, width, height)
+        svg.stream.clip()
+        svg.stream.end()
     svg.stream.transform(a=scale_x, d=scale_y, e=translate_x, f=translate_y)
 
 

weasyprint/svg/text.py

@@ -22,7 +22,7 @@ def __init__(self, pango_layout, style):
 def text(svg, node, font_size):
     """Draw text node."""
     from ..css.properties import INITIAL_VALUES
-    from ..draw import draw_first_line
+    from ..draw import draw_emojis, draw_first_line
     from ..text.line_break import split_first_line
 
     # TODO: use real computed values
@@ -121,6 +121,7 @@ def text(svg, node, font_size):
         return
 
     svg.stream.begin_text()
+    emoji_lines = []
 
     # Draw letters
     for i, ((x, y, dx, dy, r), letter) in enumerate(letters_positions):
@@ -160,10 +161,14 @@ def text(svg, node, font_size):
 
         layout.reactivate(style)
         svg.fill_stroke(node, font_size, text=True)
-        draw_first_line(
+        emojis = draw_first_line(
             svg.stream, TextBox(layout, style), 'none', 'none',
             x_position, y_position)
+        emoji_lines.append((font_size, x, y, emojis))
         svg.stream.pop_state()
         svg.cursor_position = cursor_position
 
     svg.stream.end_text()
+
+    for font_size, x, y, emojis in emoji_lines:
+        draw_emojis(svg.stream, font_size, x, y, emojis)

weasyprint/text/ffi.py

@@ -15,10 +15,20 @@
     typedef ... hb_font_t;
     typedef ... hb_face_t;
     typedef ... hb_blob_t;
+    typedef uint32_t hb_codepoint_t;
     hb_face_t * hb_font_get_face (hb_font_t *font);
     hb_blob_t * hb_face_reference_blob (hb_face_t *face);
     unsigned int hb_face_get_index (const hb_face_t *face);
+    unsigned int hb_face_get_upem (const hb_face_t *face);
     const char * hb_blob_get_data (hb_blob_t *blob, unsigned int *length);
+    bool hb_ot_color_has_png (hb_face_t *face);
+    hb_blob_t * hb_ot_color_glyph_reference_png (
+        hb_font_t *font, hb_codepoint_t glyph);
+    bool hb_ot_color_has_svg (hb_face_t *face);
+    hb_blob_t * hb_ot_color_glyph_reference_svg (
+        hb_face_t *face, hb_codepoint_t glyph);
+    void hb_blob_destroy (hb_blob_t *blob);
+
 
     // Pango