Add support for Emoji

David PHAM-VAN
Commit dbf1706870d783f95ce379c89c8148beb8316232 dbf17068 1 parent eefce198
Showing 8 changed files with 220 additions and 17 deletions
Makefile
pdf/CHANGELOG.md
pdf/lib/src/pdf/font/ttf_parser.dart
pdf/lib/src/pdf/obj/unicode_cmap.dart
pdf/lib/src/widgets/text.dart
pdf/test/widget_text_test.dart
test/build_gfonts.dart
test/golden/widgets-text.pdf
--- a/Makefile
View file @dbf1706
+++ b/Makefile
View file @dbf1706
@@ -18,7 +18,7 @@ DART_BIN=$(FLUTTER)/bin/dart
 DART_SRC=$(shell find . -name '*.dart')
 CLNG_SRC=$(shell find printing/ios printing/macos printing/windows printing/linux printing/android -name '*.cpp' -o -name '*.cc' -o -name '*.m' -o -name '*.h' -o -name '*.java')
 SWFT_SRC=$(shell find printing/ios printing/macos -name '*.swift')
-FONTS=pdf/open-sans.ttf pdf/open-sans-bold.ttf pdf/roboto.ttf pdf/noto-sans.ttf pdf/genyomintw.ttf pdf/hacen-tunisia.ttf pdf/material.ttf
+FONTS=pdf/open-sans.ttf pdf/open-sans-bold.ttf pdf/roboto.ttf pdf/noto-sans.ttf pdf/genyomintw.ttf pdf/hacen-tunisia.ttf pdf/material.ttf pdf/emoji.ttf
 COV_PORT=9292
 SVG=blend_and_mask blend_mode_devil clip_path clip_path_2 clip_path_2 clip_path_3  clip_path_3  dash_path ellipse empty_defs equation fill-rule-inherit group_composite_opacity group_fill_opacity group_mask group_opacity group_opacity_transform hidden href-fill image image_def implicit_fill_with_opacity linear_gradient linear_gradient_2 linear_gradient_absolute_user_space_translate linear_gradient_percentage_bounding_translate linear_gradient_percentage_user_space_translate linear_gradient_xlink male mask mask_with_gradient mask_with_use mask_with_use2 nested_group opacity_on_path radial_gradient radial_gradient_absolute_user_space_translate radial_gradient_focal radial_gradient_percentage_bounding_translate radial_gradient_percentage_user_space_translate radial_gradient_xlink radial_ref_linear_gradient rect_rrect rect_rrect_no_ry stroke_inherit_circles style_attr text text_2 text_3 use_circles use_circles_def use_emc2 use_fill use_opacity_grid width_height_viewbox flutter_logo emoji_u1f600 text_transform dart new-pause-button new-send-circle new-gif new-camera new-image numeric_25 new-mention new-gif-button new-action-expander new-play-button aa alphachannel Ghostscript_Tiger Firefox_Logo_2017 chess_knight Flag_of_the_United_States
@@ -42,6 +42,9 @@ pdf/genyomintw.ttf:
 pdf/material.ttf:
 	curl -L "https://github.com/google/material-design-icons/raw/master/font/MaterialIcons-Regular.ttf" > $@
+pdf/emoji.ttf:
+	curl -L https://github.com/googlefonts/noto-emoji/raw/main/fonts/NotoColorEmoji.ttf > $@
+
 demo/assets/logo.svg:
 	curl -L "http://pigment.github.io/fake-logos/logos/vector/color/auto-speed.svg" > $@
--- a/pdf/CHANGELOG.md
View file @dbf1706
+++ b/pdf/CHANGELOG.md
View file @dbf1706
@@ -5,6 +5,7 @@
 - Move files
 - Depreciate Font.stringSize
 - Implement fallback font
+- Implement Emoji support
 ## 3.6.6
--- a/pdf/lib/src/pdf/font/ttf_parser.dart
View file @dbf1706
+++ b/pdf/lib/src/pdf/font/ttf_parser.dart
View file @dbf1706
@@ -68,6 +68,52 @@ class TtfGlyphInfo {
   String toString() => 'Glyph $index $compounds';
 }
+class TtfBitmapInfo {
+  const TtfBitmapInfo(
+    this.data,
+    this.height,
+    this.width,
+    this.horiBearingX,
+    this.horiBearingY,
+    this.horiAdvance,
+    this.vertBearingX,
+    this.vertBearingY,
+    this.vertAdvance,
+    this.ascent,
+    this.descent,
+  );
+
+  final Uint8List data;
+  final int height;
+  final int width;
+  final int horiBearingX;
+  final int horiBearingY;
+  final int horiAdvance;
+  final int vertBearingX;
+  final int vertBearingY;
+  final int vertAdvance;
+  final int ascent;
+  final int descent;
+
+  PdfFontMetrics get metrics {
+    final coef = 1.0 / height;
+    return PdfFontMetrics(
+      bottom: horiBearingY * coef,
+      left: horiBearingX * coef,
+      top: horiBearingY * coef - height * coef,
+      right: horiAdvance * coef,
+      ascent: ascent * coef,
+      descent: horiBearingY * coef,
+      advanceWidth: horiAdvance * coef,
+      leftBearing: horiBearingX * coef,
+    );
+  }
+
+  @override
+  String toString() =>
+      'Bitmap Glyph ${width}x$height horiBearingX:$horiBearingX horiBearingY:$horiBearingY horiAdvance:$horiAdvance ascender:$ascent descender:$descent';
+}
+
 class TtfParser {
   TtfParser(ByteData bytes) : bytes = UnmodifiableByteDataView(bytes) {
     final numTables = bytes.getUint16(4);
@@ -92,14 +138,17 @@ class TtfParser {
         'Unable to find the `cmap` table. This file is not a supported TTF font');
     assert(tableOffsets.containsKey(maxp_table),
         'Unable to find the `maxp` table. This file is not a supported TTF font');
-    assert(tableOffsets.containsKey(loca_table),
-        'Unable to find the `loca` table. This file is not a supported TTF font');
-    assert(tableOffsets.containsKey(glyf_table),
-        'Unable to find the `glyf` table. This file is not a supported TTF font');
     _parseCMap();
-    _parseIndexes();
-    _parseGlyphs();
+    if (tableOffsets.containsKey(loca_table) &&
+        tableOffsets.containsKey(glyf_table)) {
+      _parseIndexes();
+      _parseGlyphs();
+    }
+    if (tableOffsets.containsKey(cblc_table) &&
+        tableOffsets.containsKey(cbdt_table)) {
+      _parseBitmaps();
+    }
   }
   static const String head_table = 'head';
@@ -110,14 +159,17 @@ class TtfParser {
   static const String maxp_table = 'maxp';
   static const String loca_table = 'loca';
   static const String glyf_table = 'glyf';
+  static const String cblc_table = 'CBLC';
+  static const String cbdt_table = 'CBDT';
   final UnmodifiableByteDataView bytes;
-  final Map<String, int> tableOffsets = <String, int>{};
-  final Map<String, int> tableSize = <String, int>{};
+  final tableOffsets = <String, int>{};
+  final tableSize = <String, int>{};
-  final Map<int, int> charToGlyphIndexMap = <int, int>{};
-  final List<int> glyphOffsets = <int>[];
-  final Map<int, PdfFontMetrics> glyphInfoMap = <int, PdfFontMetrics>{};
+  final charToGlyphIndexMap = <int, int>{};
+  final glyphOffsets = <int>[];
+  final glyphInfoMap = <int, PdfFontMetrics>{};
+  final bitmapOffsets = <int, TtfBitmapInfo>{};
   int get unitsPerEm => bytes.getUint16(tableOffsets[head_table]! + 18);
@@ -145,9 +197,14 @@ class TtfParser {
   bool get unicode => bytes.getUint32(0) == 0x10000;
+  bool get isBitmap => bitmapOffsets.isNotEmpty && glyphOffsets.isEmpty;
+
   // https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6name.html
   String? getNameID(TtfParserName fontNameID) {
-    final basePosition = tableOffsets[name_table]!;
+    final basePosition = tableOffsets[name_table];
+    if (basePosition == null) {
+      return null;
+    }
     // final format = bytes.getUint16(basePosition);
     final count = bytes.getUint16(basePosition + 2);
     final stringOffset = bytes.getUint16(basePosition + 4);
@@ -288,15 +345,15 @@ class TtfParser {
   }
   void _parseIndexes() {
-    final basePosition = tableOffsets[loca_table];
+    final basePosition = tableOffsets[loca_table]!;
     final numGlyphs = this.numGlyphs;
     if (indexToLocFormat == 0) {
       for (var i = 0; i < numGlyphs; i++) {
-        glyphOffsets.add(bytes.getUint16(basePosition! + i * 2) * 2);
+        glyphOffsets.add(bytes.getUint16(basePosition + i * 2) * 2);
       }
     } else {
       for (var i = 0; i < numGlyphs; i++) {
-        glyphOffsets.add(bytes.getUint32(basePosition! + i * 4));
+        glyphOffsets.add(bytes.getUint32(basePosition + i * 4));
       }
     }
   }
@@ -465,4 +522,92 @@ class TtfParser {
     }
     return String.fromCharCodes(charCodes);
   }
+
+  // https://docs.microsoft.com/en-us/typography/opentype/spec/ebdt
+  void _parseBitmaps() {
+    final baseOffset = tableOffsets[cblc_table]!;
+    final pngOffset = tableOffsets[cbdt_table]!;
+
+    // CBLC Header
+    final numSizes = bytes.getUint32(baseOffset + 4);
+    var bitmapSize = baseOffset + 8;
+
+    for (var bitmapSizeIndex = 0;
+        bitmapSizeIndex < numSizes;
+        bitmapSizeIndex++) {
+      // BitmapSize Record
+      final indexSubTableArrayOffset = baseOffset + bytes.getUint32(bitmapSize);
+      // final indexTablesSize = bytes.getUint32(bitmapSize + 4);
+      final numberOfIndexSubTables = bytes.getUint32(bitmapSize + 8);
+
+      final ascender = bytes.getInt8(bitmapSize + 12);
+      final descender = bytes.getInt8(bitmapSize + 13);
+
+      // final startGlyphIndex = bytes.getUint16(bitmapSize + 16 + 12 * 2);
+      // final endGlyphIndex = bytes.getUint16(bitmapSize + 16 + 12 * 2 + 2);
+      // final ppemX = bytes.getUint8(bitmapSize + 16 + 12 * 2 + 4);
+      // final ppemY = bytes.getUint8(bitmapSize + 16 + 12 * 2 + 5);
+      // final bitDepth = bytes.getUint8(bitmapSize + 16 + 12 * 2 + 6);
+      // final flags = bytes.getUint8(bitmapSize + 16 + 12 * 2 + 7);
+
+      var subTableArrayOffset = indexSubTableArrayOffset;
+      for (var indexSubTable = 0;
+          indexSubTable < numberOfIndexSubTables;
+          indexSubTable++) {
+        // IndexSubTableArray
+        final firstGlyphIndex = bytes.getUint16(subTableArrayOffset);
+        final lastGlyphIndex = bytes.getUint16(subTableArrayOffset + 2);
+        final additionalOffsetToIndexSubtable =
+            indexSubTableArrayOffset + bytes.getUint32(subTableArrayOffset + 4);
+
+        // IndexSubHeader
+        final indexFormat = bytes.getUint16(additionalOffsetToIndexSubtable);
+        final imageFormat =
+            bytes.getUint16(additionalOffsetToIndexSubtable + 2);
+        final imageDataOffset =
+            pngOffset + bytes.getUint32(additionalOffsetToIndexSubtable + 4);
+
+        if (indexFormat == 1) {
+          // IndexSubTable1
+
+          for (var glyph = firstGlyphIndex; glyph <= lastGlyphIndex; glyph++) {
+            final sbitOffset = imageDataOffset +
+                bytes.getUint32(additionalOffsetToIndexSubtable +
+                    (glyph - firstGlyphIndex + 2) * 4);
+
+            if (imageFormat == 17) {
+              final height = bytes.getUint8(sbitOffset);
+              final width = bytes.getUint8(sbitOffset + 1);
+              final bearingX = bytes.getInt8(sbitOffset + 2);
+              final bearingY = bytes.getInt8(sbitOffset + 3);
+              final advance = bytes.getUint8(sbitOffset + 4);
+              final dataLen = bytes.getUint32(sbitOffset + 5);
+
+              bitmapOffsets[glyph] = TtfBitmapInfo(
+                  bytes.buffer.asUint8List(
+                    bytes.offsetInBytes + sbitOffset + 9,
+                    dataLen,
+                  ),
+                  height,
+                  width,
+                  bearingX,
+                  bearingY,
+                  advance,
+                  0,
+                  0,
+                  0,
+                  ascender,
+                  descender);
+            }
+          }
+        }
+
+        subTableArrayOffset += 8;
+      }
+      bitmapSize += 16 + 12 * 2 + 8;
+    }
+  }
+
+  TtfBitmapInfo? getBitmap(int charcode) =>
+      bitmapOffsets[charToGlyphIndexMap[charcode]];
 }
--- a/pdf/lib/src/pdf/obj/unicode_cmap.dart
View file @dbf1706
+++ b/pdf/lib/src/pdf/obj/unicode_cmap.dart
View file @dbf1706
@@ -23,7 +23,7 @@ class PdfUnicodeCmap extends PdfObjectStream {
   PdfUnicodeCmap(PdfDocument pdfDocument, this.protect) : super(pdfDocument);
   /// List of characters
-  final List<int> cmap = <int>[0];
+  final cmap = <int>[];
   /// Protects the text from being "seen" by the PDF reader.
   final bool protect;
--- a/pdf/lib/src/widgets/text.dart
View file @dbf1706
+++ b/pdf/lib/src/widgets/text.dart
View file @dbf1706
@@ -24,6 +24,8 @@ import 'annotations.dart';
 import 'basic.dart';
 import 'document.dart';
 import 'geometry.dart';
+import 'image.dart';
+import 'image_provider.dart';
 import 'multi_page.dart';
 import 'placeholders.dart';
 import 'text_style.dart';
@@ -690,6 +692,25 @@ class RichText extends Widget with SpanningWidget {
     _decorations.add(td);
   }
+  InlineSpan _addEmoji({
+    required TtfBitmapInfo bitmap,
+    double baseline = 0,
+    required TextStyle style,
+    AnnotationBuilder? annotation,
+  }) {
+    final metrics = bitmap.metrics * style.fontSize!;
+
+    return WidgetSpan(
+      child: SizedBox(
+        height: style.fontSize,
+        child: Image(MemoryImage(bitmap.data)),
+      ),
+      style: style,
+      baseline: baseline + metrics.ascent + metrics.descent - metrics.height,
+      annotation: annotation,
+    );
+  }
+
   InlineSpan _addText({
     required List<int> text,
     int start = 0,
@@ -770,6 +791,19 @@ class RichText extends Widget with SpanningWidget {
           for (final fb in style.fontFallback) {
             final font = fb.getFont(context);
             if (font.isRuneSupported(rune)) {
+              if (font is PdfTtfFont) {
+                final bitmap = font.font.getBitmap(rune);
+                if (bitmap != null) {
+                  spans.add(_addEmoji(
+                    bitmap: bitmap,
+                    style: style,
+                    baseline: span.baseline,
+                    annotation: annotation,
+                  ));
+                  found = true;
+                  break;
+                }
+              }
               spans.add(_addText(
                 text: [rune],
                 style: style.copyWith(
--- a/pdf/test/widget_text_test.dart
View file @dbf1706
+++ b/pdf/test/widget_text_test.dart
View file @dbf1706
@@ -27,6 +27,7 @@ late Document pdf;
 late Font ttf;
 late Font ttfBold;
 late Font asian;
+late Font emoji;
 Iterable<TextDecoration> permute(
     List<TextDecoration> prefix, List<TextDecoration> remaining) sync* {
@@ -48,6 +49,7 @@ void main() {
     ttf = loadFont('open-sans.ttf');
     ttfBold = loadFont('open-sans-bold.ttf');
     asian = loadFont('genyomintw.ttf');
+    emoji = loadFont('emoji.ttf');
     pdf = Document();
   });
@@ -357,6 +359,20 @@ void main() {
     );
   });
+  test('Text Widgets Emojis', () {
+    pdf.addPage(
+      Page(
+        build: (Context context) => Text(
+          'Hello 🐈! Dancing 💃🏃',
+          style: TextStyle(
+            fontSize: 30,
+            fontFallback: [emoji],
+          ),
+        ),
+      ),
+    );
+  });
+
   tearDownAll(() async {
     final file = File('widgets-text.pdf');
     await file.writeAsBytes(await pdf.save());
--- a/test/build_gfonts.dart
View file @dbf1706
+++ b/test/build_gfonts.dart
View file @dbf1706
@@ -128,8 +128,12 @@ void main(List<String> args) async {
   }
   for (final entry in <String, String>{
+    'CupertinoIcons':
+        'https://github.com/flutter/packages/blob/master/third_party/packages/cupertino_icons/assets/CupertinoIcons.ttf',
     'MaterialIcons':
         'https://fonts.gstatic.com/s/materialicons/v98/flUhRq6tzZclQEJ-Vdg-IuiaDsNZ.ttf',
+    'NotoColorEmoji':
+        'https://github.com/googlefonts/noto-emoji/raw/main/fonts/NotoColorEmoji.ttf',
   }.entries) {
     output.writeln('');
     output.writeln('/// ${entry.key}');
--- a/test/golden/widgets-text.pdf
View file @dbf1706
+++ b/test/golden/widgets-text.pdf
View file @dbf1706