blob: 4d610de1a0b08d8fd66710d57ead6e32a703636b [file] [log] [blame]
/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* (C) 2000 Dirk Mueller (mueller@kde.org)
* Copyright (C) 2003, 2006, 2010, 2011 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include "config.h"
#include "core/platform/graphics/Font.h"
#include "core/platform/graphics/FloatRect.h"
#include "core/platform/graphics/TextRun.h"
#include "core/platform/graphics/WidthIterator.h"
#include "core/platform/text/transcoder/FontTranscoder.h"
#include <wtf/MainThread.h>
#include <wtf/MathExtras.h>
#include <wtf/text/StringBuilder.h>
#include <wtf/UnusedParam.h>
using namespace WTF;
using namespace Unicode;
namespace WTF {
// allow compilation of OwnPtr<TextLayout> in source files that don't have access to the TextLayout class definition
template <> void deleteOwnedPtr<WebCore::TextLayout>(WebCore::TextLayout* ptr)
{
WebCore::Font::deleteLayout(ptr);
}
}
namespace WebCore {
const uint8_t Font::s_roundingHackCharacterTable[256] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 1 /*\t*/, 1 /*\n*/, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1 /*space*/, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 /*-*/, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 /*?*/,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1 /*no-break space*/, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
Font::CodePath Font::s_codePath = Auto;
TypesettingFeatures Font::s_defaultTypesettingFeatures = 0;
// ============================================================================================
// Font Implementation (Cross-Platform Portion)
// ============================================================================================
Font::Font()
: m_letterSpacing(0)
, m_wordSpacing(0)
, m_isPlatformFont(false)
, m_needsTranscoding(false)
, m_typesettingFeatures(0)
{
}
Font::Font(const FontDescription& fd, short letterSpacing, short wordSpacing)
: m_fontDescription(fd)
, m_letterSpacing(letterSpacing)
, m_wordSpacing(wordSpacing)
, m_isPlatformFont(false)
, m_needsTranscoding(fontTranscoder().needsTranscoding(fd))
, m_typesettingFeatures(computeTypesettingFeatures())
{
}
Font::Font(const FontPlatformData& fontData, bool isPrinterFont, FontSmoothingMode fontSmoothingMode)
: m_fontFallbackList(FontFallbackList::create())
, m_letterSpacing(0)
, m_wordSpacing(0)
, m_isPlatformFont(true)
, m_typesettingFeatures(computeTypesettingFeatures())
{
m_fontDescription.setUsePrinterFont(isPrinterFont);
m_fontDescription.setFontSmoothing(fontSmoothingMode);
m_needsTranscoding = fontTranscoder().needsTranscoding(fontDescription());
m_fontFallbackList->setPlatformFont(fontData);
}
Font::Font(const Font& other)
: m_fontDescription(other.m_fontDescription)
, m_fontFallbackList(other.m_fontFallbackList)
, m_letterSpacing(other.m_letterSpacing)
, m_wordSpacing(other.m_wordSpacing)
, m_isPlatformFont(other.m_isPlatformFont)
, m_needsTranscoding(other.m_needsTranscoding)
, m_typesettingFeatures(computeTypesettingFeatures())
{
}
Font& Font::operator=(const Font& other)
{
m_fontDescription = other.m_fontDescription;
m_fontFallbackList = other.m_fontFallbackList;
m_letterSpacing = other.m_letterSpacing;
m_wordSpacing = other.m_wordSpacing;
m_isPlatformFont = other.m_isPlatformFont;
m_needsTranscoding = other.m_needsTranscoding;
m_typesettingFeatures = other.m_typesettingFeatures;
return *this;
}
bool Font::operator==(const Font& other) const
{
// Our FontData don't have to be checked, since checking the font description will be fine.
// FIXME: This does not work if the font was made with the FontPlatformData constructor.
if (loadingCustomFonts() || other.loadingCustomFonts())
return false;
FontSelector* first = m_fontFallbackList ? m_fontFallbackList->fontSelector() : 0;
FontSelector* second = other.m_fontFallbackList ? other.m_fontFallbackList->fontSelector() : 0;
return first == second
&& m_fontDescription == other.m_fontDescription
&& m_letterSpacing == other.m_letterSpacing
&& m_wordSpacing == other.m_wordSpacing
&& (m_fontFallbackList ? m_fontFallbackList->fontSelectorVersion() : 0) == (other.m_fontFallbackList ? other.m_fontFallbackList->fontSelectorVersion() : 0)
&& (m_fontFallbackList ? m_fontFallbackList->generation() : 0) == (other.m_fontFallbackList ? other.m_fontFallbackList->generation() : 0);
}
void Font::update(PassRefPtr<FontSelector> fontSelector) const
{
// FIXME: It is pretty crazy that we are willing to just poke into a RefPtr, but it ends up
// being reasonably safe (because inherited fonts in the render tree pick up the new
// style anyway. Other copies are transient, e.g., the state in the GraphicsContext, and
// won't stick around long enough to get you in trouble). Still, this is pretty disgusting,
// and could eventually be rectified by using RefPtrs for Fonts themselves.
if (!m_fontFallbackList)
m_fontFallbackList = FontFallbackList::create();
m_fontFallbackList->invalidate(fontSelector);
m_typesettingFeatures = computeTypesettingFeatures();
}
void Font::drawText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point, CustomFontNotReadyAction customFontNotReadyAction) const
{
// Don't draw anything while we are using custom fonts that are in the process of loading,
// except if the 'force' argument is set to true (in which case it will use a fallback
// font).
if (loadingCustomFonts() && customFontNotReadyAction == DoNotPaintIfFontNotReady)
return;
CodePath codePathToUse = codePath(runInfo.run);
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePathToUse != Complex && typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
codePathToUse = Complex;
if (codePathToUse != Complex)
return drawSimpleText(context, runInfo, point);
return drawComplexText(context, runInfo, point);
}
void Font::drawEmphasisMarks(GraphicsContext* context, const TextRunPaintInfo& runInfo, const AtomicString& mark, const FloatPoint& point) const
{
if (loadingCustomFonts())
return;
CodePath codePathToUse = codePath(runInfo.run);
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePathToUse != Complex && typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
codePathToUse = Complex;
if (codePathToUse != Complex)
drawEmphasisMarksForSimpleText(context, runInfo, mark, point);
else
drawEmphasisMarksForComplexText(context, runInfo, mark, point);
}
float Font::width(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const
{
CodePath codePathToUse = codePath(run);
if (codePathToUse != Complex) {
// The complex path is more restrictive about returning fallback fonts than the simple path, so we need an explicit test to make their behaviors match.
if (!canReturnFallbackFontsForComplexText())
fallbackFonts = 0;
// The simple path can optimize the case where glyph overflow is not observable.
if (codePathToUse != SimpleWithGlyphOverflow && (glyphOverflow && !glyphOverflow->computeBounds))
glyphOverflow = 0;
}
bool hasKerningOrLigatures = typesettingFeatures() & (Kerning | Ligatures);
bool hasWordSpacingOrLetterSpacing = wordSpacing() | letterSpacing();
float* cacheEntry = m_fontFallbackList->widthCache().add(run, std::numeric_limits<float>::quiet_NaN(), hasKerningOrLigatures, hasWordSpacingOrLetterSpacing, glyphOverflow);
if (cacheEntry && !std::isnan(*cacheEntry))
return *cacheEntry;
float result;
if (codePathToUse == Complex)
result = floatWidthForComplexText(run, fallbackFonts, glyphOverflow);
else
result = floatWidthForSimpleText(run, fallbackFonts, glyphOverflow);
if (cacheEntry && (!fallbackFonts || fallbackFonts->isEmpty()))
*cacheEntry = result;
return result;
}
float Font::width(const TextRun& run, int& charsConsumed, String& glyphName) const
{
#if ENABLE(SVG_FONTS)
if (TextRun::RenderingContext* renderingContext = run.renderingContext())
return renderingContext->floatWidthUsingSVGFont(*this, run, charsConsumed, glyphName);
#endif
charsConsumed = run.length();
glyphName = "";
return width(run);
}
#if !OS(DARWIN)
PassOwnPtr<TextLayout> Font::createLayout(RenderText*, float, bool) const
{
return nullptr;
}
void Font::deleteLayout(TextLayout*)
{
}
float Font::width(TextLayout&, unsigned, unsigned, HashSet<const SimpleFontData*>*)
{
ASSERT_NOT_REACHED();
return 0;
}
#endif
FloatRect Font::selectionRectForText(const TextRun& run, const FloatPoint& point, int h, int from, int to) const
{
to = (to == -1 ? run.length() : to);
CodePath codePathToUse = codePath(run);
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePathToUse != Complex && typesettingFeatures() && (from || to != run.length()))
codePathToUse = Complex;
if (codePathToUse != Complex)
return selectionRectForSimpleText(run, point, h, from, to);
return selectionRectForComplexText(run, point, h, from, to);
}
int Font::offsetForPosition(const TextRun& run, float x, bool includePartialGlyphs) const
{
// FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
if (codePath(run) != Complex && !typesettingFeatures())
return offsetForPositionForSimpleText(run, x, includePartialGlyphs);
return offsetForPositionForComplexText(run, x, includePartialGlyphs);
}
template <typename CharacterType>
static inline String normalizeSpacesInternal(const CharacterType* characters, unsigned length)
{
StringBuilder normalized;
normalized.reserveCapacity(length);
for (unsigned i = 0; i < length; ++i)
normalized.append(Font::normalizeSpaces(characters[i]));
return normalized.toString();
}
String Font::normalizeSpaces(const LChar* characters, unsigned length)
{
return normalizeSpacesInternal(characters, length);
}
String Font::normalizeSpaces(const UChar* characters, unsigned length)
{
return normalizeSpacesInternal(characters, length);
}
static bool shouldUseFontSmoothing = true;
void Font::setShouldUseSmoothing(bool shouldUseSmoothing)
{
ASSERT(isMainThread());
shouldUseFontSmoothing = shouldUseSmoothing;
}
bool Font::shouldUseSmoothing()
{
return shouldUseFontSmoothing;
}
void Font::setCodePath(CodePath p)
{
s_codePath = p;
}
Font::CodePath Font::codePath()
{
return s_codePath;
}
void Font::setDefaultTypesettingFeatures(TypesettingFeatures typesettingFeatures)
{
s_defaultTypesettingFeatures = typesettingFeatures;
}
TypesettingFeatures Font::defaultTypesettingFeatures()
{
return s_defaultTypesettingFeatures;
}
Font::CodePath Font::codePath(const TextRun& run) const
{
if (s_codePath != Auto)
return s_codePath;
#if ENABLE(SVG_FONTS)
if (run.renderingContext())
return Simple;
#endif
if (m_fontDescription.featureSettings() && m_fontDescription.featureSettings()->size() > 0)
return Complex;
if (run.length() > 1 && !WidthIterator::supportsTypesettingFeatures(*this))
return Complex;
if (!run.characterScanForCodePath())
return Simple;
if (run.is8Bit())
return Simple;
// Start from 0 since drawing and highlighting also measure the characters before run->from.
return characterRangeCodePath(run.characters16(), run.length());
}
Font::CodePath Font::characterRangeCodePath(const UChar* characters, unsigned len)
{
// FIXME: Should use a UnicodeSet in ports where ICU is used. Note that we
// can't simply use UnicodeCharacter Property/class because some characters
// are not 'combining', but still need to go to the complex path.
// Alternatively, we may as well consider binary search over a sorted
// list of ranges.
CodePath result = Simple;
for (unsigned i = 0; i < len; i++) {
const UChar c = characters[i];
if (c < 0x2E5) // U+02E5 through U+02E9 (Modifier Letters : Tone letters)
continue;
if (c <= 0x2E9)
return Complex;
if (c < 0x300) // U+0300 through U+036F Combining diacritical marks
continue;
if (c <= 0x36F)
return Complex;
if (c < 0x0591 || c == 0x05BE) // U+0591 through U+05CF excluding U+05BE Hebrew combining marks, Hebrew punctuation Paseq, Sof Pasuq and Nun Hafukha
continue;
if (c <= 0x05CF)
return Complex;
// U+0600 through U+109F Arabic, Syriac, Thaana, NKo, Samaritan, Mandaic,
// Devanagari, Bengali, Gurmukhi, Gujarati, Oriya, Tamil, Telugu, Kannada,
// Malayalam, Sinhala, Thai, Lao, Tibetan, Myanmar
if (c < 0x0600)
continue;
if (c <= 0x109F)
return Complex;
// U+1100 through U+11FF Hangul Jamo (only Ancient Korean should be left here if you precompose;
// Modern Korean will be precomposed as a result of step A)
if (c < 0x1100)
continue;
if (c <= 0x11FF)
return Complex;
if (c < 0x135D) // U+135D through U+135F Ethiopic combining marks
continue;
if (c <= 0x135F)
return Complex;
if (c < 0x1700) // U+1780 through U+18AF Tagalog, Hanunoo, Buhid, Taghanwa,Khmer, Mongolian
continue;
if (c <= 0x18AF)
return Complex;
if (c < 0x1900) // U+1900 through U+194F Limbu (Unicode 4.0)
continue;
if (c <= 0x194F)
return Complex;
if (c < 0x1980) // U+1980 through U+19DF New Tai Lue
continue;
if (c <= 0x19DF)
return Complex;
if (c < 0x1A00) // U+1A00 through U+1CFF Buginese, Tai Tham, Balinese, Batak, Lepcha, Vedic
continue;
if (c <= 0x1CFF)
return Complex;
if (c < 0x1DC0) // U+1DC0 through U+1DFF Comining diacritical mark supplement
continue;
if (c <= 0x1DFF)
return Complex;
// U+1E00 through U+2000 characters with diacritics and stacked diacritics
if (c <= 0x2000) {
result = SimpleWithGlyphOverflow;
continue;
}
if (c < 0x20D0) // U+20D0 through U+20FF Combining marks for symbols
continue;
if (c <= 0x20FF)
return Complex;
if (c < 0x2CEF) // U+2CEF through U+2CF1 Combining marks for Coptic
continue;
if (c <= 0x2CF1)
return Complex;
if (c < 0x302A) // U+302A through U+302F Ideographic and Hangul Tone marks
continue;
if (c <= 0x302F)
return Complex;
if (c < 0xA67C) // U+A67C through U+A67D Combining marks for old Cyrillic
continue;
if (c <= 0xA67D)
return Complex;
if (c < 0xA6F0) // U+A6F0 through U+A6F1 Combining mark for Bamum
continue;
if (c <= 0xA6F1)
return Complex;
// U+A800 through U+ABFF Nagri, Phags-pa, Saurashtra, Devanagari Extended,
// Hangul Jamo Ext. A, Javanese, Myanmar Extended A, Tai Viet, Meetei Mayek,
if (c < 0xA800)
continue;
if (c <= 0xABFF)
return Complex;
if (c < 0xD7B0) // U+D7B0 through U+D7FF Hangul Jamo Ext. B
continue;
if (c <= 0xD7FF)
return Complex;
if (c <= 0xDBFF) {
// High surrogate
if (i == len - 1)
continue;
UChar next = characters[++i];
if (!U16_IS_TRAIL(next))
continue;
UChar32 supplementaryCharacter = U16_GET_SUPPLEMENTARY(c, next);
if (supplementaryCharacter < 0x1F1E6) // U+1F1E6 through U+1F1FF Regional Indicator Symbols
continue;
if (supplementaryCharacter <= 0x1F1FF)
return Complex;
if (supplementaryCharacter < 0xE0100) // U+E0100 through U+E01EF Unicode variation selectors.
continue;
if (supplementaryCharacter <= 0xE01EF)
return Complex;
// FIXME: Check for Brahmi (U+11000 block), Kaithi (U+11080 block) and other complex scripts
// in plane 1 or higher.
continue;
}
if (c < 0xFE00) // U+FE00 through U+FE0F Unicode variation selectors
continue;
if (c <= 0xFE0F)
return Complex;
if (c < 0xFE20) // U+FE20 through U+FE2F Combining half marks
continue;
if (c <= 0xFE2F)
return Complex;
}
return result;
}
bool Font::isCJKIdeograph(UChar32 c)
{
// The basic CJK Unified Ideographs block.
if (c >= 0x4E00 && c <= 0x9FFF)
return true;
// CJK Unified Ideographs Extension A.
if (c >= 0x3400 && c <= 0x4DBF)
return true;
// CJK Radicals Supplement.
if (c >= 0x2E80 && c <= 0x2EFF)
return true;
// Kangxi Radicals.
if (c >= 0x2F00 && c <= 0x2FDF)
return true;
// CJK Strokes.
if (c >= 0x31C0 && c <= 0x31EF)
return true;
// CJK Compatibility Ideographs.
if (c >= 0xF900 && c <= 0xFAFF)
return true;
// CJK Unified Ideographs Extension B.
if (c >= 0x20000 && c <= 0x2A6DF)
return true;
// CJK Unified Ideographs Extension C.
if (c >= 0x2A700 && c <= 0x2B73F)
return true;
// CJK Unified Ideographs Extension D.
if (c >= 0x2B740 && c <= 0x2B81F)
return true;
// CJK Compatibility Ideographs Supplement.
if (c >= 0x2F800 && c <= 0x2FA1F)
return true;
return false;
}
bool Font::isCJKIdeographOrSymbol(UChar32 c)
{
// 0x2C7 Caron, Mandarin Chinese 3rd Tone
// 0x2CA Modifier Letter Acute Accent, Mandarin Chinese 2nd Tone
// 0x2CB Modifier Letter Grave Access, Mandarin Chinese 4th Tone
// 0x2D9 Dot Above, Mandarin Chinese 5th Tone
if ((c == 0x2C7) || (c == 0x2CA) || (c == 0x2CB) || (c == 0x2D9))
return true;
if ((c == 0x2020) || (c == 0x2021) || (c == 0x2030) || (c == 0x203B) || (c == 0x203C)
|| (c == 0x2042) || (c == 0x2047) || (c == 0x2048) || (c == 0x2049) || (c == 0x2051)
|| (c == 0x20DD) || (c == 0x20DE) || (c == 0x2100) || (c == 0x2103) || (c == 0x2105)
|| (c == 0x2109) || (c == 0x210A) || (c == 0x2113) || (c == 0x2116) || (c == 0x2121)
|| (c == 0x212B) || (c == 0x213B) || (c == 0x2150) || (c == 0x2151) || (c == 0x2152))
return true;
if (c >= 0x2156 && c <= 0x215A)
return true;
if (c >= 0x2160 && c <= 0x216B)
return true;
if (c >= 0x2170 && c <= 0x217B)
return true;
if ((c == 0x217F) || (c == 0x2189) || (c == 0x2307) || (c == 0x2312) || (c == 0x23BE) || (c == 0x23BF))
return true;
if (c >= 0x23C0 && c <= 0x23CC)
return true;
if ((c == 0x23CE) || (c == 0x2423))
return true;
if (c >= 0x2460 && c <= 0x2492)
return true;
if (c >= 0x249C && c <= 0x24FF)
return true;
if ((c == 0x25A0) || (c == 0x25A1) || (c == 0x25A2) || (c == 0x25AA) || (c == 0x25AB))
return true;
if ((c == 0x25B1) || (c == 0x25B2) || (c == 0x25B3) || (c == 0x25B6) || (c == 0x25B7) || (c == 0x25BC) || (c == 0x25BD))
return true;
if ((c == 0x25C0) || (c == 0x25C1) || (c == 0x25C6) || (c == 0x25C7) || (c == 0x25C9) || (c == 0x25CB) || (c == 0x25CC))
return true;
if (c >= 0x25CE && c <= 0x25D3)
return true;
if (c >= 0x25E2 && c <= 0x25E6)
return true;
if (c == 0x25EF)
return true;
if (c >= 0x2600 && c <= 0x2603)
return true;
if ((c == 0x2605) || (c == 0x2606) || (c == 0x260E) || (c == 0x2616) || (c == 0x2617) || (c == 0x2640) || (c == 0x2642))
return true;
if (c >= 0x2660 && c <= 0x266F)
return true;
if (c >= 0x2672 && c <= 0x267D)
return true;
if ((c == 0x26A0) || (c == 0x26BD) || (c == 0x26BE) || (c == 0x2713) || (c == 0x271A) || (c == 0x273F) || (c == 0x2740) || (c == 0x2756))
return true;
if (c >= 0x2776 && c <= 0x277F)
return true;
if (c == 0x2B1A)
return true;
// Ideographic Description Characters.
if (c >= 0x2FF0 && c <= 0x2FFF)
return true;
// CJK Symbols and Punctuation, excluding 0x3030.
if (c >= 0x3000 && c < 0x3030)
return true;
if (c > 0x3030 && c <= 0x303F)
return true;
// Hiragana
if (c >= 0x3040 && c <= 0x309F)
return true;
// Katakana
if (c >= 0x30A0 && c <= 0x30FF)
return true;
// Bopomofo
if (c >= 0x3100 && c <= 0x312F)
return true;
if (c >= 0x3190 && c <= 0x319F)
return true;
// Bopomofo Extended
if (c >= 0x31A0 && c <= 0x31BF)
return true;
// Enclosed CJK Letters and Months.
if (c >= 0x3200 && c <= 0x32FF)
return true;
// CJK Compatibility.
if (c >= 0x3300 && c <= 0x33FF)
return true;
if (c >= 0xF860 && c <= 0xF862)
return true;
// CJK Compatibility Forms.
if (c >= 0xFE30 && c <= 0xFE4F)
return true;
if ((c == 0xFE10) || (c == 0xFE11) || (c == 0xFE12) || (c == 0xFE19))
return true;
if ((c == 0xFF0D) || (c == 0xFF1B) || (c == 0xFF1C) || (c == 0xFF1E))
return false;
// Halfwidth and Fullwidth Forms
// Usually only used in CJK
if (c >= 0xFF00 && c <= 0xFFEF)
return true;
// Emoji.
if (c == 0x1F100)
return true;
if (c >= 0x1F110 && c <= 0x1F129)
return true;
if (c >= 0x1F130 && c <= 0x1F149)
return true;
if (c >= 0x1F150 && c <= 0x1F169)
return true;
if (c >= 0x1F170 && c <= 0x1F189)
return true;
if (c >= 0x1F200 && c <= 0x1F6F)
return true;
return isCJKIdeograph(c);
}
unsigned Font::expansionOpportunityCount(const LChar* characters, size_t length, TextDirection direction, bool& isAfterExpansion)
{
unsigned count = 0;
if (direction == LTR) {
for (size_t i = 0; i < length; ++i) {
if (treatAsSpace(characters[i])) {
count++;
isAfterExpansion = true;
} else
isAfterExpansion = false;
}
} else {
for (size_t i = length; i > 0; --i) {
if (treatAsSpace(characters[i - 1])) {
count++;
isAfterExpansion = true;
} else
isAfterExpansion = false;
}
}
return count;
}
unsigned Font::expansionOpportunityCount(const UChar* characters, size_t length, TextDirection direction, bool& isAfterExpansion)
{
static bool expandAroundIdeographs = canExpandAroundIdeographsInComplexText();
unsigned count = 0;
if (direction == LTR) {
for (size_t i = 0; i < length; ++i) {
UChar32 character = characters[i];
if (treatAsSpace(character)) {
count++;
isAfterExpansion = true;
continue;
}
if (U16_IS_LEAD(character) && i + 1 < length && U16_IS_TRAIL(characters[i + 1])) {
character = U16_GET_SUPPLEMENTARY(character, characters[i + 1]);
i++;
}
if (expandAroundIdeographs && isCJKIdeographOrSymbol(character)) {
if (!isAfterExpansion)
count++;
count++;
isAfterExpansion = true;
continue;
}
isAfterExpansion = false;
}
} else {
for (size_t i = length; i > 0; --i) {
UChar32 character = characters[i - 1];
if (treatAsSpace(character)) {
count++;
isAfterExpansion = true;
continue;
}
if (U16_IS_TRAIL(character) && i > 1 && U16_IS_LEAD(characters[i - 2])) {
character = U16_GET_SUPPLEMENTARY(characters[i - 2], character);
i--;
}
if (expandAroundIdeographs && isCJKIdeographOrSymbol(character)) {
if (!isAfterExpansion)
count++;
count++;
isAfterExpansion = true;
continue;
}
isAfterExpansion = false;
}
}
return count;
}
bool Font::canReceiveTextEmphasis(UChar32 c)
{
CharCategory category = Unicode::category(c);
if (category & (Separator_Space | Separator_Line | Separator_Paragraph | Other_NotAssigned | Other_Control | Other_Format))
return false;
// Additional word-separator characters listed in CSS Text Level 3 Editor's Draft 3 November 2010.
if (c == ethiopicWordspace || c == aegeanWordSeparatorLine || c == aegeanWordSeparatorDot
|| c == ugariticWordDivider || c == tibetanMarkIntersyllabicTsheg || c == tibetanMarkDelimiterTshegBstar)
return false;
return true;
}
}