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      1 /*
      2  * (C) 1999 Lars Knoll (knoll (at) kde.org)
      3  * (C) 2000 Dirk Mueller (mueller (at) kde.org)
      4  * Copyright (C) 2004, 2005, 2006, 2009, 2010, 2011 Apple Inc. All rights reserved.
      5  *
      6  * This library is free software; you can redistribute it and/or
      7  * modify it under the terms of the GNU Library General Public
      8  * License as published by the Free Software Foundation; either
      9  * version 2 of the License, or (at your option) any later version.
     10  *
     11  * This library is distributed in the hope that it will be useful,
     12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14  * Library General Public License for more details.
     15  *
     16  * You should have received a copy of the GNU Library General Public License
     17  * along with this library; see the file COPYING.LIB.  If not, write to
     18  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     19  * Boston, MA 02110-1301, USA.
     20  *
     21  */
     22 
     23 #ifndef InlineTextBox_h
     24 #define InlineTextBox_h
     25 
     26 #include "core/rendering/InlineBox.h"
     27 #include "core/rendering/RenderText.h" // so textRenderer() can be inline
     28 #include "platform/text/TextRun.h"
     29 #include "wtf/Forward.h"
     30 
     31 namespace WebCore {
     32 
     33 struct CompositionUnderline;
     34 class DocumentMarker;
     35 class GraphicsContext;
     36 
     37 const unsigned short cNoTruncation = USHRT_MAX;
     38 const unsigned short cFullTruncation = USHRT_MAX - 1;
     39 
     40 // Helper functions shared by InlineTextBox / SVGRootInlineBox
     41 void updateGraphicsContext(GraphicsContext*, const Color& fillColor, const Color& strokeColor, float strokeThickness, ColorSpace);
     42 Color correctedTextColor(Color textColor, Color backgroundColor);
     43 
     44 class InlineTextBox : public InlineBox {
     45 public:
     46     InlineTextBox(RenderObject& obj)
     47         : InlineBox(obj)
     48         , m_prevTextBox(0)
     49         , m_nextTextBox(0)
     50         , m_start(0)
     51         , m_len(0)
     52         , m_truncation(cNoTruncation)
     53     {
     54     }
     55 
     56     virtual void destroy() OVERRIDE FINAL;
     57 
     58     InlineTextBox* prevTextBox() const { return m_prevTextBox; }
     59     InlineTextBox* nextTextBox() const { return m_nextTextBox; }
     60     void setNextTextBox(InlineTextBox* n) { m_nextTextBox = n; }
     61     void setPreviousTextBox(InlineTextBox* p) { m_prevTextBox = p; }
     62 
     63     // FIXME: These accessors should ASSERT(!isDirty()). See https://bugs.webkit.org/show_bug.cgi?id=97264
     64     unsigned start() const { return m_start; }
     65     unsigned end() const { return m_len ? m_start + m_len - 1 : m_start; }
     66     unsigned len() const { return m_len; }
     67 
     68     void setStart(unsigned start) { m_start = start; }
     69     void setLen(unsigned len) { m_len = len; }
     70 
     71     void offsetRun(int d) { ASSERT(!isDirty()); m_start += d; }
     72 
     73     unsigned short truncation() { return m_truncation; }
     74 
     75     virtual void markDirty() OVERRIDE FINAL;
     76 
     77     using InlineBox::hasHyphen;
     78     using InlineBox::setHasHyphen;
     79     using InlineBox::canHaveLeadingExpansion;
     80     using InlineBox::setCanHaveLeadingExpansion;
     81 
     82     static inline bool compareByStart(const InlineTextBox* first, const InlineTextBox* second) { return first->start() < second->start(); }
     83 
     84     virtual int baselinePosition(FontBaseline) const OVERRIDE FINAL;
     85     virtual LayoutUnit lineHeight() const OVERRIDE FINAL;
     86 
     87     bool getEmphasisMarkPosition(RenderStyle*, TextEmphasisPosition&) const;
     88 
     89     LayoutRect logicalOverflowRect() const;
     90     void setLogicalOverflowRect(const LayoutRect&);
     91     LayoutUnit logicalTopVisualOverflow() const { return logicalOverflowRect().y(); }
     92     LayoutUnit logicalBottomVisualOverflow() const { return logicalOverflowRect().maxY(); }
     93     LayoutUnit logicalLeftVisualOverflow() const { return logicalOverflowRect().x(); }
     94     LayoutUnit logicalRightVisualOverflow() const { return logicalOverflowRect().maxX(); }
     95 
     96 #ifndef NDEBUG
     97     virtual void showBox(int = 0) const OVERRIDE;
     98     virtual const char* boxName() const OVERRIDE;
     99 #endif
    100 
    101     enum RotationDirection { Counterclockwise, Clockwise };
    102     static AffineTransform rotation(const FloatRect& boxRect, RotationDirection);
    103 private:
    104     LayoutUnit selectionTop();
    105     LayoutUnit selectionBottom();
    106     LayoutUnit selectionHeight();
    107 
    108     // charactersWithHyphen, if provided, must not be destroyed before the TextRun.
    109     TextRun constructTextRun(RenderStyle*, const Font&, StringBuilder* charactersWithHyphen = 0) const;
    110     TextRun constructTextRun(RenderStyle*, const Font&, StringView, int maximumLength, StringBuilder* charactersWithHyphen = 0) const;
    111 
    112 public:
    113     TextRun constructTextRunForInspector(RenderStyle*, const Font&) const;
    114     virtual FloatRect calculateBoundaries() const OVERRIDE { return FloatRect(x(), y(), width(), height()); }
    115 
    116     virtual LayoutRect localSelectionRect(int startPos, int endPos);
    117     bool isSelected(int startPos, int endPos) const;
    118     void selectionStartEnd(int& sPos, int& ePos);
    119 
    120 protected:
    121     virtual void paint(PaintInfo&, const LayoutPoint&, LayoutUnit lineTop, LayoutUnit lineBottom) OVERRIDE;
    122     virtual bool nodeAtPoint(const HitTestRequest&, HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, LayoutUnit lineTop, LayoutUnit lineBottom) OVERRIDE;
    123 
    124 public:
    125     RenderText& textRenderer() const;
    126 
    127 private:
    128     virtual void deleteLine() OVERRIDE FINAL;
    129     virtual void extractLine() OVERRIDE FINAL;
    130     virtual void attachLine() OVERRIDE FINAL;
    131 
    132 public:
    133     virtual RenderObject::SelectionState selectionState() OVERRIDE FINAL;
    134 
    135 private:
    136     virtual void clearTruncation() OVERRIDE FINAL { m_truncation = cNoTruncation; }
    137     virtual float placeEllipsisBox(bool flowIsLTR, float visibleLeftEdge, float visibleRightEdge, float ellipsisWidth, float &truncatedWidth, bool& foundBox) OVERRIDE FINAL;
    138 
    139 public:
    140     virtual bool isLineBreak() const OVERRIDE FINAL;
    141 
    142     void setExpansion(int newExpansion)
    143     {
    144         m_logicalWidth -= expansion();
    145         InlineBox::setExpansion(newExpansion);
    146         m_logicalWidth += newExpansion;
    147     }
    148 
    149 private:
    150     virtual bool isInlineTextBox() const OVERRIDE FINAL { return true; }
    151 
    152 public:
    153     virtual int caretMinOffset() const OVERRIDE FINAL;
    154     virtual int caretMaxOffset() const OVERRIDE FINAL;
    155 
    156 private:
    157     float textPos() const; // returns the x position relative to the left start of the text line.
    158 
    159 public:
    160     virtual int offsetForPosition(float x, bool includePartialGlyphs = true) const;
    161     virtual float positionForOffset(int offset) const;
    162 
    163     bool containsCaretOffset(int offset) const; // false for offset after line break
    164 
    165     // Fills a vector with the pixel width of each character.
    166     void characterWidths(Vector<float>&) const;
    167 
    168 private:
    169     InlineTextBox* m_prevTextBox; // The previous box that also uses our RenderObject
    170     InlineTextBox* m_nextTextBox; // The next box that also uses our RenderObject
    171 
    172     int m_start;
    173     unsigned short m_len;
    174 
    175     unsigned short m_truncation; // Where to truncate when text overflow is applied.  We use special constants to
    176                       // denote no truncation (the whole run paints) and full truncation (nothing paints at all).
    177 
    178     unsigned underlinePaintStart(const CompositionUnderline&);
    179     unsigned underlinePaintEnd(const CompositionUnderline&);
    180 
    181 protected:
    182     void paintSingleCompositionBackgroundRun(GraphicsContext*, const FloatPoint& boxOrigin, RenderStyle*, const Font&, Color backgroundColor, int startPos, int endPos);
    183     void paintCompositionBackgrounds(GraphicsContext*, const FloatPoint& boxOrigin, RenderStyle*, const Font&, bool useCustomUnderlines);
    184     void paintDocumentMarkers(GraphicsContext*, const FloatPoint& boxOrigin, RenderStyle*, const Font&, bool background);
    185     void paintCompositionUnderline(GraphicsContext*, const FloatPoint& boxOrigin, const CompositionUnderline&);
    186 
    187     // These functions both paint markers and update the DocumentMarker's renderedRect.
    188     virtual void paintDocumentMarker(GraphicsContext*, const FloatPoint& boxOrigin, DocumentMarker*, RenderStyle*, const Font&, bool grammar);
    189     virtual void paintTextMatchMarker(GraphicsContext*, const FloatPoint& boxOrigin, DocumentMarker*, RenderStyle*, const Font&);
    190 
    191 private:
    192     void paintDecoration(GraphicsContext*, const FloatPoint& boxOrigin, TextDecoration, const ShadowList*);
    193     void paintSelection(GraphicsContext*, const FloatPoint& boxOrigin, RenderStyle*, const Font&, Color textColor);
    194 
    195     TextRun::ExpansionBehavior expansionBehavior() const
    196     {
    197         return (canHaveLeadingExpansion() ? TextRun::AllowLeadingExpansion : TextRun::ForbidLeadingExpansion)
    198             | (expansion() && nextLeafChild() ? TextRun::AllowTrailingExpansion : TextRun::ForbidTrailingExpansion);
    199     }
    200 };
    201 
    202 DEFINE_INLINE_BOX_TYPE_CASTS(InlineTextBox);
    203 
    204 inline RenderText& InlineTextBox::textRenderer() const
    205 {
    206     return toRenderText(renderer());
    207 }
    208 
    209 void alignSelectionRectToDevicePixels(FloatRect&);
    210 
    211 inline AffineTransform InlineTextBox::rotation(const FloatRect& boxRect, RotationDirection rotationDirection)
    212 {
    213     return rotationDirection == Clockwise ? AffineTransform(0, 1, -1, 0, boxRect.x() + boxRect.maxY(), boxRect.maxY() - boxRect.x())
    214         : AffineTransform(0, -1, 1, 0, boxRect.x() - boxRect.maxY(), boxRect.x() + boxRect.maxY());
    215 }
    216 
    217 } // namespace WebCore
    218 
    219 #endif // InlineTextBox_h
    220