third_party/WebKit/Source/core/layout/line/LineWidth.h

   1 /*
   2  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1. Redistributions of source code must retain the above
   9  *    copyright notice, this list of conditions and the following
  10  *    disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above
  12  *    copyright notice, this list of conditions and the following
  13  *    disclaimer in the documentation and/or other materials
  14  *    provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  19  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  20  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  27  * OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #ifndef LineWidth_h
  31 #define LineWidth_h
  32
  33 #include "core/layout/api/LineLayoutBlockFlow.h"
  34 #include "platform/LayoutUnit.h"
  35 #include "wtf/Allocator.h"
  36
  37 namespace blink {
  38
  39 class FloatingObject;
  40 class LineLayoutRubyRun;
  41
  42 enum IndentTextOrNot { DoNotIndentText, IndentText };
  43 enum WhitespaceTreatment { ExcludeWhitespace, IncludeWhitespace };
  44
  45 class LineWidth {
  46     STACK_ALLOCATED();
  47 public:
  48     LineWidth(LineLayoutBlockFlow, bool isFirstLine, IndentTextOrNot shouldIndentText);
  49
  50     bool fitsOnLine() const { return currentWidth() <= (m_availableWidth + LayoutUnit::epsilon()); }
  51     bool fitsOnLine(float extra) const { return currentWidth() + extra <= (m_availableWidth + LayoutUnit::epsilon()); }
  52     bool fitsOnLine(float extra, WhitespaceTreatment whitespaceTreatment) const
  53     {
  54         return currentWidth() - (whitespaceTreatment == ExcludeWhitespace ? trailingWhitespaceWidth() : 0) + extra <= (m_availableWidth + LayoutUnit::epsilon());
  55     }
  56
  57     float currentWidth() const { return m_committedWidth + m_uncommittedWidth; }
  58     // FIXME: We should eventually replace these three functions by ones that work on a higher abstraction.
  59     float uncommittedWidth() const { return m_uncommittedWidth; }
  60     float committedWidth() const { return m_committedWidth; }
  61     float availableWidth() const { return m_availableWidth; }
  62     float trailingWhitespaceWidth() const { return m_trailingWhitespaceWidth; }
  63
  64     void updateAvailableWidth(LayoutUnit minimumHeight = 0);
  65     void shrinkAvailableWidthForNewFloatIfNeeded(const FloatingObject&);
  66     void addUncommittedWidth(float delta) { m_uncommittedWidth += delta; }
  67     void commit();
  68     void applyOverhang(LineLayoutRubyRun, LineLayoutItem startLayoutItem, LineLayoutItem endLayoutItem);
  69     void fitBelowFloats(bool isFirstLine = false);
  70     void setTrailingWhitespaceWidth(float width) { m_trailingWhitespaceWidth = width; }
  71
  72     bool shouldIndentText() const { return m_shouldIndentText == IndentText; }
  73
  74 private:
  75     void computeAvailableWidthFromLeftAndRight();
  76     void updateLineDimension(LayoutUnit newLineTop, LayoutUnit newLineWidth, const float& newLineLeft, const float& newLineRight);
  77     void wrapNextToShapeOutside(bool isFirstLine);
  78
  79     LineLayoutBlockFlow m_block;
  80     float m_uncommittedWidth;
  81     float m_committedWidth;
  82     float m_overhangWidth; // The amount by which |m_availableWidth| has been inflated to account for possible contraction due to ruby overhang.
  83     float m_trailingWhitespaceWidth;
  84     float m_left;
  85     float m_right;
  86     float m_availableWidth;
  87     bool m_isFirstLine;
  88     IndentTextOrNot m_shouldIndentText;
  89 };
  90
  91 }
  92
  93 #endif // LineWidth_h