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/*
* Copyright (C) 2007, 2008, 2009, 2011 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "FloatPoint.h"
#include "GlyphBuffer.h"
#include <wtf/HashSet.h>
#include <wtf/RefCounted.h>
#include <wtf/RetainPtr.h>
#include <wtf/Vector.h>
#include <wtf/text/WTFString.h>
typedef unsigned short CGGlyph;
typedef const struct __CTRun * CTRunRef;
typedef const struct __CTLine * CTLineRef;
typedef struct hb_buffer_t hb_buffer_t;
namespace WebCore {
class FontCascade;
class Font;
class TextRun;
enum GlyphIterationStyle { IncludePartialGlyphs, ByWholeGlyphs };
// See https://trac.webkit.org/wiki/ComplexTextController for more information about ComplexTextController.
class ComplexTextController {
WTF_MAKE_FAST_ALLOCATED;
public:
ComplexTextController(const FontCascade&, const TextRun&, bool mayUseNaturalWritingDirection = false, HashSet<const Font*>* fallbackFonts = 0, bool forTextEmphasis = false);
class ComplexTextRun;
WEBCORE_EXPORT ComplexTextController(const FontCascade&, const TextRun&, Vector<Ref<ComplexTextRun>>&);
// Advance and emit glyphs up to the specified character.
WEBCORE_EXPORT void advance(unsigned to, GlyphBuffer* = nullptr, GlyphIterationStyle = IncludePartialGlyphs, HashSet<const Font*>* fallbackFonts = nullptr);
// Compute the character offset for a given x coordinate.
unsigned offsetForPosition(float x, bool includePartialGlyphs);
// Returns the width of everything we've consumed so far.
float runWidthSoFar() const { return m_runWidthSoFar; }
FloatSize totalAdvance() const { return m_totalAdvance; }
float minGlyphBoundingBoxX() const { return m_minGlyphBoundingBoxX; }
float maxGlyphBoundingBoxX() const { return m_maxGlyphBoundingBoxX; }
float minGlyphBoundingBoxY() const { return m_minGlyphBoundingBoxY; }
float maxGlyphBoundingBoxY() const { return m_maxGlyphBoundingBoxY; }
class ComplexTextRun : public RefCounted<ComplexTextRun> {
public:
static Ref<ComplexTextRun> create(CTRunRef ctRun, const Font& font, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd)
{
return adoptRef(*new ComplexTextRun(ctRun, font, characters, stringLocation, stringLength, indexBegin, indexEnd));
}
static Ref<ComplexTextRun> create(hb_buffer_t* buffer, const Font& font, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd)
{
return adoptRef(*new ComplexTextRun(buffer, font, characters, stringLocation, stringLength, indexBegin, indexEnd));
}
static Ref<ComplexTextRun> create(const Font& font, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd, bool ltr)
{
return adoptRef(*new ComplexTextRun(font, characters, stringLocation, stringLength, indexBegin, indexEnd, ltr));
}
static Ref<ComplexTextRun> create(const Vector<FloatSize>& advances, const Vector<FloatPoint>& origins, const Vector<Glyph>& glyphs, const Vector<unsigned>& stringIndices, FloatSize initialAdvance, const Font& font, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd, bool ltr)
{
return adoptRef(*new ComplexTextRun(advances, origins, glyphs, stringIndices, initialAdvance, font, characters, stringLocation, stringLength, indexBegin, indexEnd, ltr));
}
unsigned glyphCount() const { return m_glyphCount; }
const Font& font() const { return m_font; }
const UChar* characters() const { return m_characters; }
unsigned stringLocation() const { return m_stringLocation; }
unsigned stringLength() const { return m_stringLength; }
ALWAYS_INLINE unsigned indexAt(unsigned) const;
unsigned indexBegin() const { return m_indexBegin; }
unsigned indexEnd() const { return m_indexEnd; }
unsigned endOffsetAt(unsigned i) const { ASSERT(!m_isMonotonic); return m_glyphEndOffsets[i]; }
const CGGlyph* glyphs() const { return m_glyphs.data(); }
void growInitialAdvanceHorizontally(float delta) { m_initialAdvance.expand(delta, 0); }
FloatSize initialAdvance() const { return m_initialAdvance; }
const FloatSize* baseAdvances() const { return m_baseAdvances.data(); }
const FloatPoint* glyphOrigins() const { return m_glyphOrigins.size() == glyphCount() ? m_glyphOrigins.data() : nullptr; }
bool isLTR() const { return m_isLTR; }
bool isMonotonic() const { return m_isMonotonic; }
void setIsNonMonotonic();
private:
ComplexTextRun(CTRunRef, const Font&, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd);
ComplexTextRun(hb_buffer_t*, const Font&, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd);
ComplexTextRun(const Font&, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd, bool ltr);
WEBCORE_EXPORT ComplexTextRun(const Vector<FloatSize>& advances, const Vector<FloatPoint>& origins, const Vector<Glyph>& glyphs, const Vector<unsigned>& stringIndices, FloatSize initialAdvance, const Font&, const UChar* characters, unsigned stringLocation, unsigned stringLength, unsigned indexBegin, unsigned indexEnd, bool ltr);
Vector<FloatSize, 64> m_baseAdvances;
Vector<FloatPoint, 64> m_glyphOrigins;
Vector<CGGlyph, 64> m_glyphs;
Vector<unsigned, 64> m_glyphEndOffsets;
Vector<unsigned, 64> m_coreTextIndices;
FloatSize m_initialAdvance;
const Font& m_font;
const UChar* m_characters;
unsigned m_stringLength;
unsigned m_indexBegin;
unsigned m_indexEnd;
unsigned m_glyphCount;
unsigned m_stringLocation;
bool m_isLTR;
bool m_isMonotonic { true };
};
private:
void computeExpansionOpportunity();
void finishConstruction();
static unsigned stringBegin(const ComplexTextRun& run) { return run.stringLocation() + run.indexBegin(); }
static unsigned stringEnd(const ComplexTextRun& run) { return run.stringLocation() + run.indexEnd(); }
void collectComplexTextRuns();
void collectComplexTextRunsForCharacters(const UChar*, unsigned length, unsigned stringLocation, const Font*);
void adjustGlyphsAndAdvances();
unsigned indexOfCurrentRun(unsigned& leftmostGlyph);
unsigned incrementCurrentRun(unsigned& leftmostGlyph);
float runWidthSoFarFraction(unsigned glyphStartOffset, unsigned glyphEndOffset, unsigned oldCharacterInCurrentGlyph, GlyphIterationStyle) const;
FloatPoint glyphOrigin(unsigned index) const { return index < m_glyphOrigins.size() ? m_glyphOrigins[index] : FloatPoint(); }
Vector<FloatSize, 256> m_adjustedBaseAdvances;
Vector<FloatPoint, 256> m_glyphOrigins;
Vector<CGGlyph, 256> m_adjustedGlyphs;
Vector<UChar, 256> m_smallCapsBuffer;
// There is a 3-level hierarchy here. At the top, we are interested in m_run.string(). We partition that string
// into Lines, each of which is a sequence of characters which should use the same Font. Core Text then partitions
// the Line into ComplexTextRuns.
// ComplexTextRun::stringLocation() and ComplexTextRun::stringLength() refer to the offset and length of the Line
// relative to m_run.string(). ComplexTextRun::indexAt() returns to the offset of a codepoint relative to
// its Line. ComplexTextRun::glyphs() and ComplexTextRun::advances() refer to glyphs relative to the ComplexTextRun.
// The length of the entire TextRun is m_run.length()
Vector<RefPtr<ComplexTextRun>, 16> m_complexTextRuns;
// The initial capacity of these vectors was selected as being the smallest power of two greater than
// the average (3.5) plus one standard deviation (7.5) of nonzero sizes used on Arabic Wikipedia.
Vector<unsigned, 16> m_runIndices;
Vector<unsigned, 16> m_glyphCountFromStartToIndex;
#if PLATFORM(COCOA)
Vector<RetainPtr<CTLineRef>> m_coreTextLines;
#endif
Vector<String> m_stringsFor8BitRuns;
HashSet<const Font*>* m_fallbackFonts { nullptr };
const FontCascade& m_font;
const TextRun& m_run;
unsigned m_currentCharacter { 0 };
unsigned m_end { 0 };
FloatSize m_totalAdvance;
float m_runWidthSoFar { 0 };
unsigned m_numGlyphsSoFar { 0 };
unsigned m_currentRun { 0 };
unsigned m_glyphInCurrentRun { 0 };
unsigned m_characterInCurrentGlyph { 0 };
float m_expansion { 0 };
float m_expansionPerOpportunity { 0 };
float m_minGlyphBoundingBoxX { std::numeric_limits<float>::max() };
float m_maxGlyphBoundingBoxX { std::numeric_limits<float>::lowest() };
float m_minGlyphBoundingBoxY { std::numeric_limits<float>::max() };
float m_maxGlyphBoundingBoxY { std::numeric_limits<float>::min() };
bool m_isLTROnly { true };
bool m_mayUseNaturalWritingDirection { false };
bool m_forTextEmphasis { false };
};
} // namespace WebCore