src/third_party/WebKit/Source/core/rendering/line/LineWidth.cpp

   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 #include "config.h"
  31 #include "core/rendering/line/LineWidth.h"
  32
  33 #include "core/rendering/RenderBlock.h"
  34 #include "core/rendering/RenderRubyRun.h"
  35
  36 namespace WebCore {
  37
  38 LineWidth::LineWidth(RenderBlockFlow& block, bool isFirstLine, IndentTextOrNot shouldIndentText)
  39     : m_block(block)
  40     , m_uncommittedWidth(0)
  41     , m_committedWidth(0)
  42     , m_overhangWidth(0)
  43     , m_left(0)
  44     , m_right(0)
  45     , m_availableWidth(0)
  46     , m_segment(0)
  47     , m_isFirstLine(isFirstLine)
  48     , m_shouldIndentText(shouldIndentText)
  49 {
  50     updateCurrentShapeSegment();
  51     updateAvailableWidth();
  52 }
  53
  54 void LineWidth::updateAvailableWidth(LayoutUnit replacedHeight)
  55 {
  56     LayoutUnit height = m_block.logicalHeight();
  57     LayoutUnit logicalHeight = m_block.minLineHeightForReplacedRenderer(m_isFirstLine, replacedHeight);
  58     m_left = m_block.logicalLeftOffsetForLine(height, shouldIndentText(), logicalHeight);
  59     m_right = m_block.logicalRightOffsetForLine(height, shouldIndentText(), logicalHeight);
  60
  61     if (m_segment) {
  62         m_left = std::max<float>(m_segment->logicalLeft, m_left);
  63         m_right = std::min<float>(m_segment->logicalRight, m_right);
  64     }
  65
  66     computeAvailableWidthFromLeftAndRight();
  67 }
  68
  69 void LineWidth::shrinkAvailableWidthForNewFloatIfNeeded(FloatingObject* newFloat)
  70 {
  71     LayoutUnit height = m_block.logicalHeight();
  72     if (height < m_block.logicalTopForFloat(newFloat) || height >= m_block.logicalBottomForFloat(newFloat))
  73         return;
  74
  75     // When floats with shape outside are stacked, the floats are positioned based on the margin box of the float,
  76     // not the shape's contour. Since we computed the width based on the shape contour when we added the float,
  77     // when we add a subsequent float on the same line, we need to undo the shape delta in order to position
  78     // based on the margin box. In order to do this, we need to walk back through the floating object list to find
  79     // the first previous float that is on the same side as our newFloat.
  80     ShapeOutsideInfo* previousShapeOutsideInfo = 0;
  81     const FloatingObjectSet& floatingObjectSet = m_block.m_floatingObjects->set();
  82     FloatingObjectSetIterator it = floatingObjectSet.end();
  83     FloatingObjectSetIterator begin = floatingObjectSet.begin();
  84     LayoutUnit lineHeight = m_block.lineHeight(m_isFirstLine, m_block.isHorizontalWritingMode() ? HorizontalLine : VerticalLine, PositionOfInteriorLineBoxes);
  85     for (--it; it != begin; --it) {
  86         FloatingObject* previousFloat = *it;
  87         if (previousFloat != newFloat && previousFloat->type() == newFloat->type()) {
  88             previousShapeOutsideInfo = previousFloat->renderer()->shapeOutsideInfo();
  89             if (previousShapeOutsideInfo)
  90                 previousShapeOutsideInfo->updateDeltasForContainingBlockLine(&m_block, previousFloat, m_block.logicalHeight(), lineHeight);
  91             break;
  92         }
  93     }
  94
  95     ShapeOutsideInfo* shapeOutsideInfo = newFloat->renderer()->shapeOutsideInfo();
  96     if (shapeOutsideInfo)
  97         shapeOutsideInfo->updateDeltasForContainingBlockLine(&m_block, newFloat, m_block.logicalHeight(), lineHeight);
  98
  99     if (newFloat->type() == FloatingObject::FloatLeft) {
 100         float newLeft = m_block.logicalRightForFloat(newFloat);
 101         if (previousShapeOutsideInfo)
 102             newLeft -= previousShapeOutsideInfo->rightMarginBoxDelta();
 103         if (shapeOutsideInfo)
 104             newLeft += shapeOutsideInfo->rightMarginBoxDelta();
 105
 106         if (shouldIndentText() && m_block.style()->isLeftToRightDirection())
 107             newLeft += floorToInt(m_block.textIndentOffset());
 108         m_left = std::max<float>(m_left, newLeft);
 109     } else {
 110         float newRight = m_block.logicalLeftForFloat(newFloat);
 111         if (previousShapeOutsideInfo)
 112             newRight -= previousShapeOutsideInfo->leftMarginBoxDelta();
 113         if (shapeOutsideInfo)
 114             newRight += shapeOutsideInfo->leftMarginBoxDelta();
 115
 116         if (shouldIndentText() && !m_block.style()->isLeftToRightDirection())
 117             newRight -= floorToInt(m_block.textIndentOffset());
 118         m_right = std::min<float>(m_right, newRight);
 119     }
 120
 121     computeAvailableWidthFromLeftAndRight();
 122 }
 123
 124 void LineWidth::commit()
 125 {
 126     m_committedWidth += m_uncommittedWidth;
 127     m_uncommittedWidth = 0;
 128 }
 129
 130 void LineWidth::applyOverhang(RenderRubyRun* rubyRun, RenderObject* startRenderer, RenderObject* endRenderer)
 131 {
 132     int startOverhang;
 133     int endOverhang;
 134     rubyRun->getOverhang(m_isFirstLine, startRenderer, endRenderer, startOverhang, endOverhang);
 135
 136     startOverhang = std::min<int>(startOverhang, m_committedWidth);
 137     m_availableWidth += startOverhang;
 138
 139     endOverhang = std::max(std::min<int>(endOverhang, m_availableWidth - currentWidth()), 0);
 140     m_availableWidth += endOverhang;
 141     m_overhangWidth += startOverhang + endOverhang;
 142 }
 143
 144 void LineWidth::fitBelowFloats()
 145 {
 146     ASSERT(!m_committedWidth);
 147     ASSERT(!fitsOnLine());
 148
 149     LayoutUnit floatLogicalBottom;
 150     LayoutUnit lastFloatLogicalBottom = m_block.logicalHeight();
 151     float newLineWidth = m_availableWidth;
 152     float newLineLeft = m_left;
 153     float newLineRight = m_right;
 154     while (true) {
 155         floatLogicalBottom = m_block.nextFloatLogicalBottomBelow(lastFloatLogicalBottom, ShapeOutsideFloatShapeOffset);
 156         if (floatLogicalBottom <= lastFloatLogicalBottom)
 157             break;
 158
 159         newLineLeft = m_block.logicalLeftOffsetForLine(floatLogicalBottom, shouldIndentText());
 160         newLineRight = m_block.logicalRightOffsetForLine(floatLogicalBottom, shouldIndentText());
 161         newLineWidth = max(0.0f, newLineRight - newLineLeft);
 162         lastFloatLogicalBottom = floatLogicalBottom;
 163
 164         // FIXME: This code should be refactored to incorporate with the code above.
 165         ShapeInsideInfo* shapeInsideInfo = m_block.layoutShapeInsideInfo();
 166         if (shapeInsideInfo) {
 167             LayoutUnit logicalOffsetFromShapeContainer = m_block.logicalOffsetFromShapeAncestorContainer(shapeInsideInfo->owner()).height();
 168             LayoutUnit lineHeight = m_block.lineHeight(false, m_block.isHorizontalWritingMode() ? HorizontalLine : VerticalLine, PositionOfInteriorLineBoxes);
 169             shapeInsideInfo->updateSegmentsForLine(lastFloatLogicalBottom + logicalOffsetFromShapeContainer, lineHeight);
 170             updateCurrentShapeSegment();
 171             updateAvailableWidth();
 172         }
 173
 174         if (newLineWidth >= m_uncommittedWidth)
 175             break;
 176     }
 177
 178     if (newLineWidth > m_availableWidth) {
 179         m_block.setLogicalHeight(lastFloatLogicalBottom);
 180         m_availableWidth = newLineWidth + m_overhangWidth;
 181         m_left = newLineLeft;
 182         m_right = newLineRight;
 183     }
 184 }
 185
 186 void LineWidth::updateCurrentShapeSegment()
 187 {
 188     if (ShapeInsideInfo* shapeInsideInfo = m_block.layoutShapeInsideInfo())
 189         m_segment = shapeInsideInfo->currentSegment();
 190 }
 191
 192 void LineWidth::computeAvailableWidthFromLeftAndRight()
 193 {
 194     m_availableWidth = max(0.0f, m_right - m_left) + m_overhangWidth;
 195 }
 196
 197 }