const SimpleFontData* Font::fontDataForCombiningCharacterSequence(const UChar* characters, size_t length, FontDataVariant variant) const
{
UChar32 baseCharacter;
size_t baseCharacterLength = 0;
U16_NEXT(characters, baseCharacterLength, length, baseCharacter);
GlyphData baseCharacterGlyphData = glyphDataForCharacter(baseCharacter, false, variant);
if (!baseCharacterGlyphData.glyph)
return 0;
if (length == baseCharacterLength)
return baseCharacterGlyphData.fontData;
bool triedBaseCharacterFontData = false;
unsigned i = 0;
for (const FontData* fontData = fontDataAt(0); fontData; fontData = fontDataAt(++i)) {
const SimpleFontData* simpleFontData = fontData->fontDataForCharacter(baseCharacter);
if (variant == NormalVariant) {
if (simpleFontData->platformData().orientation() == Vertical) {
if (isCJKIdeographOrSymbol(baseCharacter) && !simpleFontData->hasVerticalGlyphs()) {
variant = BrokenIdeographVariant;
simpleFontData = simpleFontData->brokenIdeographFontData().get();
} else if (m_fontDescription.nonCJKGlyphOrientation() == NonCJKGlyphOrientationVerticalRight) {
SimpleFontData* verticalRightFontData = simpleFontData->verticalRightOrientationFontData().get();
Glyph verticalRightGlyph = verticalRightFontData->glyphForCharacter(baseCharacter);
if (verticalRightGlyph == baseCharacterGlyphData.glyph)
simpleFontData = verticalRightFontData;
} else {
SimpleFontData* uprightFontData = simpleFontData->uprightOrientationFontData().get();
Glyph uprightGlyph = uprightFontData->glyphForCharacter(baseCharacter);
if (uprightGlyph != baseCharacterGlyphData.glyph)
simpleFontData = uprightFontData;
}
}
} else {
if (const SimpleFontData* variantFontData = simpleFontData->variantFontData(m_fontDescription, variant).get())
simpleFontData = variantFontData;
}
if (simpleFontData == baseCharacterGlyphData.fontData)
triedBaseCharacterFontData = true;
if (simpleFontData->canRenderCombiningCharacterSequence(characters, length))
return simpleFontData;
}
if (!triedBaseCharacterFontData && baseCharacterGlyphData.fontData && baseCharacterGlyphData.fontData->canRenderCombiningCharacterSequence(characters, length))
return baseCharacterGlyphData.fontData;
return SimpleFontData::systemFallback();
}
static bool canUseForText(const CharacterType* text, unsigned length, const SimpleFontData& fontData)
{
// FIXME: <textarea maxlength=0> generates empty text node.
if (!length)
return false;
for (unsigned i = 0; i < length; ++i) {
UChar character = text[i];
if (character == ' ')
continue;
// These would be easy to support.
if (character == noBreakSpace)
return false;
if (character == softHyphen)
return false;
UCharDirection direction = u_charDirection(character);
if (direction == U_RIGHT_TO_LEFT || direction == U_RIGHT_TO_LEFT_ARABIC
|| direction == U_RIGHT_TO_LEFT_EMBEDDING || direction == U_RIGHT_TO_LEFT_OVERRIDE
|| direction == U_LEFT_TO_RIGHT_EMBEDDING || direction == U_LEFT_TO_RIGHT_OVERRIDE
|| direction == U_POP_DIRECTIONAL_FORMAT || direction == U_BOUNDARY_NEUTRAL)
return false;
if (!fontData.glyphForCharacter(character))
return false;
}
return true;
}
