LineWidth.h   [plain text]


/*
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#pragma once

#include "LayoutUnit.h"

namespace WebCore {

class FloatingObject;
class RenderBlockFlow;
class RenderObject;
class RenderRubyRun;
class RenderStyle;

struct LineSegment;

enum IndentTextOrNot { DoNotIndentText, IndentText };

class LineWidth {
public:
    LineWidth(RenderBlockFlow&, bool isFirstLine, IndentTextOrNot shouldIndentText);

    bool fitsOnLine(bool ignoringTrailingSpace = false) const;
    bool fitsOnLineIncludingExtraWidth(float extra) const;
    bool fitsOnLineExcludingTrailingWhitespace(float extra) const;

    float currentWidth() const { return m_committedWidth + m_uncommittedWidth; }
    // FIXME: We should eventually replace these three functions by ones that work on a higher abstraction.
    float uncommittedWidth() const { return m_uncommittedWidth; }
    float committedWidth() const { return m_committedWidth; }
    float availableWidth() const { return m_availableWidth; }
    float logicalLeftOffset() const { return m_left; }
    
    bool hasCommitted() const { return m_hasCommitted; }
    bool hasCommittedReplaced() const { return m_hasCommittedReplaced; }

    void updateAvailableWidth(LayoutUnit minimumHeight = 0_lu);
    void shrinkAvailableWidthForNewFloatIfNeeded(const FloatingObject&);
    void addUncommittedWidth(float delta)
    {
        m_uncommittedWidth += delta;
    }
    void addUncommittedReplacedWidth(float delta)
    {
        addUncommittedWidth(delta);
        m_hasUncommittedReplaced = true;
    }
    void commit();
    void applyOverhang(const RenderRubyRun&, RenderObject* startRenderer, RenderObject* endRenderer);
    void fitBelowFloats(bool isFirstLine = false);
    void setTrailingWhitespaceWidth(float collapsedWhitespace, float borderPaddingMargin = 0);
    IndentTextOrNot shouldIndentText() const { return m_shouldIndentText; }
    
    bool isFirstLine() const { return m_isFirstLine; }

private:
    void computeAvailableWidthFromLeftAndRight();
    bool fitsOnLineExcludingTrailingCollapsedWhitespace() const;
    void updateLineDimension(LayoutUnit newLineTop, LayoutUnit newLineWidth, float newLineLeft, float newLineRight);
    void wrapNextToShapeOutside(bool isFirstLine);

    RenderBlockFlow& m_block;
    float m_uncommittedWidth { 0 };
    float m_committedWidth { 0 };
    float m_overhangWidth { 0 }; // The amount by which |m_availableWidth| has been inflated to account for possible contraction due to ruby overhang.
    float m_trailingWhitespaceWidth { 0 };
    float m_trailingCollapsedWhitespaceWidth { 0 };
    float m_left { 0 };
    float m_right { 0 };
    float m_availableWidth { 0 };
    bool m_isFirstLine { true };
    bool m_hasCommitted { false };
    bool m_hasCommittedReplaced { false };
    bool m_hasUncommittedReplaced { false };
    IndentTextOrNot m_shouldIndentText;
};

IndentTextOrNot requiresIndent(bool isFirstLine, bool isAfterHardLineBreak, const RenderStyle&);

} // namespace WebCore