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Diffstat (limited to 'Source/WebCore/rendering/RenderCombineText.cpp')
-rw-r--r-- | Source/WebCore/rendering/RenderCombineText.cpp | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/Source/WebCore/rendering/RenderCombineText.cpp b/Source/WebCore/rendering/RenderCombineText.cpp new file mode 100644 index 0000000..1b20bd8 --- /dev/null +++ b/Source/WebCore/rendering/RenderCombineText.cpp @@ -0,0 +1,135 @@ +/* + * Copyright (C) 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 "RenderCombineText.h" + +#include "TextRun.h" + +namespace WebCore { + +const float textCombineMargin = 1.1f; // Allow em + 10% margin + +RenderCombineText::RenderCombineText(Node* node, PassRefPtr<StringImpl> string) + : RenderText(node, string) + , m_combinedTextWidth(0) + , m_isCombined(false) + , m_needsFontUpdate(false) +{ +} + +void RenderCombineText::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle) +{ + RenderText::styleDidChange(diff, oldStyle); + + if (m_isCombined) + RenderText::setTextInternal(originalText()); // This RenderCombineText has been combined once. Restore the original text for the next combineText(). + + m_needsFontUpdate = true; +} + +void RenderCombineText::setTextInternal(PassRefPtr<StringImpl> text) +{ + RenderText::setTextInternal(text); + + m_needsFontUpdate = true; +} + +unsigned RenderCombineText::width(unsigned from, unsigned length, const Font& font, int xPosition, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const +{ + if (!characters()) + return 0; + + if (m_isCombined) + return font.size(); + + return RenderText::width(from, length, font, xPosition, fallbackFonts, glyphOverflow); +} + +void RenderCombineText::adjustTextOrigin(IntPoint& textOrigin, const IntRect& boxRect) const +{ + if (m_isCombined) + textOrigin.move(boxRect.height() / 2 - ceilf(m_combinedTextWidth) / 2, style()->font().pixelSize()); +} + +void RenderCombineText::charactersToRender(int start, const UChar*& characters, int& length) const +{ + if (m_isCombined) { + length = originalText()->length(); + characters = originalText()->characters(); + return; + } + + characters = text()->characters() + start; +} + +void RenderCombineText::combineText() +{ + if (!m_needsFontUpdate) + return; + + m_isCombined = false; + m_needsFontUpdate = false; + + // CSS3 spec says text-combine works only in vertical writing mode. + if (style()->isHorizontalWritingMode()) + return; + + TextRun run = TextRun(String(text())); + FontDescription description = style()->font().fontDescription(); + float emWidth = description.computedSize() * textCombineMargin; + bool shouldUpdateFont = false; + + description.setOrientation(Horizontal); // We are going to draw combined text horizontally. + m_combinedTextWidth = style()->font().floatWidth(run); + m_isCombined = m_combinedTextWidth <= emWidth; + + if (m_isCombined) + shouldUpdateFont = style()->setFontDescription(description); // Need to change font orientation to horizontal. + else { + // Need to try compressed glyphs. + static const FontWidthVariant widthVariants[] = { HalfWidth, ThirdWidth, QuarterWidth }; + for (size_t i = 0 ; i < WTF_ARRAY_LENGTH(widthVariants) ; ++i) { + description.setWidthVariant(widthVariants[i]); + Font compressedFont = Font(description, style()->font().letterSpacing(), style()->font().wordSpacing()); + compressedFont.update(style()->font().fontSelector()); + float runWidth = compressedFont.floatWidth(run); + if (runWidth <= emWidth) { + m_combinedTextWidth = runWidth; + m_isCombined = true; + + // Replace my font with the new one. + shouldUpdateFont = style()->setFontDescription(description); + break; + } + } + } + + if (shouldUpdateFont) + style()->font().update(style()->font().fontSelector()); + + if (m_isCombined) { + static const UChar newCharacter = objectReplacementCharacter; + DEFINE_STATIC_LOCAL(String, objectReplacementCharacterString, (&newCharacter, 1)); + RenderText::setTextInternal(objectReplacementCharacterString.impl()); + } +} + +} // namespace WebCore |