LibDraw: Add emoji support to the Font class

#490
SerenityOS · Sep 5, 2019 · 27380b9 · 27380b9
1 parent 9d64c60
commit 27380b9
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Showing 3 changed files with 36 additions and 9 deletions.
diff --git a/Libraries/LibC/Makefile b/Libraries/LibC/Makefile
@@ -12,7 +12,8 @@ AK_OBJS = \
  ../../AK/JsonObject.o \
  ../../AK/JsonParser.o \
  ../../AK/LogStream.o \
- ../../AK/MappedFile.o
+ ../../AK/MappedFile.o \
+ ../../AK/Utf8View.o
 
 LIBC_OBJS = \
  SharedBuffer.o \

diff --git a/Libraries/LibDraw/Font.cpp b/Libraries/LibDraw/Font.cpp
@@ -8,6 +8,9 @@
 #include <LibC/mman.h>
 #include <LibC/stdio.h>
 #include <LibC/unistd.h>
+#include <AK/Utf8View.h>
+#include "Emoji.h"
+#include "GraphicsBitmap.h"
 
 struct [[gnu::packed]] FontFileHeader
 {
@@ -170,17 +173,37 @@ bool Font::write_to_file(const StringView& path)
  return true;
 }
 
-int Font::width(const StringView& string) const
+int Font::glyph_or_emoji_width(u32 codepoint) const
 {
- if (!string.length())
- return 0;
+ if (codepoint < 256)
+ return glyph_width((char)codepoint);
 
  if (m_fixed_width)
- return string.length() * m_glyph_width;
+ return m_glyph_width;
+
+ auto emoji = Emoji::emoji_for_codepoint(codepoint);
+ if (emoji == nullptr)
+ return glyph_width('?');
+ return emoji->bitmap().size().width();
+}
+
+int Font::width(const StringView& string) const
+{
+ Utf8View utf8 { string };
+ return width(utf8);
+}
 
+int Font::width(const Utf8View& utf8) const
+{
+ bool first = true;
  int width = 0;
- for (int i = 0; i < string.length(); ++i)
- width += glyph_width(string.characters_without_null_termination()[i]) + 1;
 
- return width - 1;
+ for (u32 codepoint : utf8) {
+ if (!first)
+ width += glyph_spacing();
+ first = false;
+ width += glyph_or_emoji_width(codepoint);
+ }
+
+ return width;
 }
diff --git a/Libraries/LibDraw/Font.h b/Libraries/LibDraw/Font.h
@@ -6,6 +6,7 @@
 #include <AK/RefCounted.h>
 #include <AK/Types.h>
 #include <LibDraw/Rect.h>
+#include <AK/Utf8View.h>
 
 // FIXME: Make a MutableGlyphBitmap buddy class for FontEditor instead?
 class GlyphBitmap {
@@ -58,11 +59,13 @@ class Font : public RefCounted<Font> {
  GlyphBitmap glyph_bitmap(char ch) const { return GlyphBitmap(&m_rows[(u8)ch * m_glyph_height], { glyph_width(ch), m_glyph_height }); }
 
  u8 glyph_width(char ch) const { return m_fixed_width ? m_glyph_width : m_glyph_widths[(u8)ch]; }
+ int glyph_or_emoji_width(u32 codepoint) const;
  u8 glyph_height() const { return m_glyph_height; }
  u8 min_glyph_width() const { return m_min_glyph_width; }
  u8 max_glyph_width() const { return m_max_glyph_width; }
  u8 glyph_spacing() const { return m_fixed_width ? 0 : 1; }
- int width(const StringView& string) const;
+ int width(const StringView&) const;
+ int width(const Utf8View&) const;
 
  String name() const { return m_name; }
  void set_name(const StringView& name) { m_name = name; }