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/*
* Copyright (C) 2000 Lars Knoll (knoll@kde.org)
* Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
* Copyright (C) 2010 Google Inc. All rights reserved.
* Copyright (C) 2013 ChangSeok Oh <shivamidow@gmail.com>
* Copyright (C) 2013 Adobe Systems Inc. All right reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#pragma once
#include "RenderLayer.h"
namespace WebCore {
enum WhitespacePosition { LeadingWhitespace, TrailingWhitespace };
inline bool hasInlineDirectionBordersPaddingOrMargin(const RenderInline& flow)
{
// Where an empty inline is split across anonymous blocks we should only give lineboxes to the 'sides' of the
// inline that have borders, padding or margin.
bool shouldApplyStartBorderPaddingOrMargin = !flow.parent()->isAnonymousBlock() || !flow.isContinuation();
if (shouldApplyStartBorderPaddingOrMargin && (flow.borderStart() || flow.marginStart() || flow.paddingStart()))
return true;
bool shouldApplyEndBorderPaddingOrMargin = !flow.parent()->isAnonymousBlock() || flow.isContinuation() || !flow.inlineContinuation();
return shouldApplyEndBorderPaddingOrMargin && (flow.borderEnd() || flow.marginEnd() || flow.paddingEnd());
}
inline const RenderStyle& lineStyle(const RenderObject& renderer, const LineInfo& lineInfo)
{
return lineInfo.isFirstLine() ? renderer.firstLineStyle() : renderer.style();
}
inline bool requiresLineBoxForContent(const RenderInline& flow, const LineInfo& lineInfo)
{
RenderElement* parent = flow.parent();
if (flow.document().inNoQuirksMode()) {
const RenderStyle& flowStyle = lineStyle(flow, lineInfo);
const RenderStyle& parentStyle = lineStyle(*parent, lineInfo);
if (flowStyle.lineHeight() != parentStyle.lineHeight()
|| flowStyle.verticalAlign() != parentStyle.verticalAlign()
|| !parentStyle.fontCascade().fontMetrics().hasIdenticalAscentDescentAndLineGap(flowStyle.fontCascade().fontMetrics()))
return true;
}
return false;
}
inline bool shouldCollapseWhiteSpace(const RenderStyle* style, const LineInfo& lineInfo, WhitespacePosition whitespacePosition)
{
// CSS2 16.6.1
// If a space (U+0020) at the beginning of a line has 'white-space' set to 'normal', 'nowrap', or 'pre-line', it is removed.
// If a space (U+0020) at the end of a line has 'white-space' set to 'normal', 'nowrap', or 'pre-line', it is also removed.
// If spaces (U+0020) or tabs (U+0009) at the end of a line have 'white-space' set to 'pre-wrap', UAs may visually collapse them.
return style->collapseWhiteSpace()
|| (whitespacePosition == TrailingWhitespace && style->whiteSpace() == PRE_WRAP && (!lineInfo.isEmpty() || !lineInfo.previousLineBrokeCleanly()));
}
inline bool skipNonBreakingSpace(const InlineIterator& it, const LineInfo& lineInfo)
{
if (it.renderer()->style().nbspMode() != SPACE || it.current() != noBreakSpace)
return false;
// FIXME: This is bad. It makes nbsp inconsistent with space and won't work correctly
// with m_minWidth/m_maxWidth.
// Do not skip a non-breaking space if it is the first character
// on a line after a clean line break (or on the first line, since previousLineBrokeCleanly starts off
// |true|).
if (lineInfo.isEmpty() && lineInfo.previousLineBrokeCleanly())
return false;
return true;
}
inline bool alwaysRequiresLineBox(const RenderInline& flow)
{
// FIXME: Right now, we only allow line boxes for inlines that are truly empty.
// We need to fix this, though, because at the very least, inlines containing only
// ignorable whitespace should should also have line boxes.
return isEmptyInline(flow) && hasInlineDirectionBordersPaddingOrMargin(flow);
}
inline bool requiresLineBox(const InlineIterator& it, const LineInfo& lineInfo = LineInfo(), WhitespacePosition whitespacePosition = LeadingWhitespace)
{
if (it.renderer()->isFloatingOrOutOfFlowPositioned())
return false;
if (it.renderer()->isBR())
return true;
bool rendererIsEmptyInline = false;
if (is<RenderInline>(*it.renderer())) {
const auto& inlineRenderer = downcast<RenderInline>(*it.renderer());
if (!alwaysRequiresLineBox(inlineRenderer) && !requiresLineBoxForContent(inlineRenderer, lineInfo))
return false;
rendererIsEmptyInline = isEmptyInline(inlineRenderer);
}
if (!shouldCollapseWhiteSpace(&it.renderer()->style(), lineInfo, whitespacePosition))
return true;
UChar current = it.current();
bool notJustWhitespace = current != ' ' && current != '\t' && current != softHyphen && (current != '\n' || it.renderer()->preservesNewline()) && !skipNonBreakingSpace(it, lineInfo);
return notJustWhitespace || rendererIsEmptyInline;
}
inline void setStaticPositions(RenderBlockFlow& block, RenderBox& child, IndentTextOrNot shouldIndentText)
{
// FIXME: The math here is actually not really right. It's a best-guess approximation that
// will work for the common cases
RenderElement* containerBlock = child.container();
LayoutUnit blockHeight = block.logicalHeight();
if (is<RenderInline>(*containerBlock)) {
// A relative positioned inline encloses us. In this case, we also have to determine our
// position as though we were an inline. Set |staticInlinePosition| and |staticBlockPosition| on the relative positioned
// inline so that we can obtain the value later.
downcast<RenderInline>(*containerBlock).layer()->setStaticInlinePosition(block.startAlignedOffsetForLine(blockHeight, DoNotIndentText));
downcast<RenderInline>(*containerBlock).layer()->setStaticBlockPosition(blockHeight);
}
block.updateStaticInlinePositionForChild(child, blockHeight, shouldIndentText);
child.layer()->setStaticBlockPosition(blockHeight);
}
} // namespace WebCore