xref: /external/chromium_org/third_party/WebKit/Source/core/rendering/RenderRubyText.cpp

/*
 * Copyright (C) 2009 Google Inc. All rights reserved.
 * Copyright (C) 2011 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
 * distribution.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#include "config.h"

#include "core/rendering/RenderRubyText.h"

namespace blink {

RenderRubyText::RenderRubyText(Element* element)
    : RenderBlockFlow(element)
{
}

RenderRubyText::~RenderRubyText()
{
}

bool RenderRubyText::isChildAllowed(RenderObject* child, RenderStyle*) const
{
    return child->isInline();
}

ETextAlign RenderRubyText::textAlignmentForLine(bool endsWithSoftBreak) const
{
    ETextAlign textAlign = style()->textAlign();
    // FIXME: This check is bogus since user can set the initial value.
    if (textAlign != RenderStyle::initialTextAlign())
        return RenderBlockFlow::textAlignmentForLine(endsWithSoftBreak);

    // The default behavior is to allow ruby text to expand if it is shorter than the ruby base.
    return JUSTIFY;
}

void RenderRubyText::adjustInlineDirectionLineBounds(unsigned expansionOpportunityCount, float& logicalLeft, float& logicalWidth) const
{
    ETextAlign textAlign = style()->textAlign();
    // FIXME: This check is bogus since user can set the initial value.
    if (textAlign != RenderStyle::initialTextAlign())
        return RenderBlockFlow::adjustInlineDirectionLineBounds(expansionOpportunityCount, logicalLeft, logicalWidth);

    int maxPreferredLogicalWidth = this->maxPreferredLogicalWidth();
    if (maxPreferredLogicalWidth >= logicalWidth)
        return;

    // Inset the ruby text by half the inter-ideograph expansion amount, but no more than a full-width
    // ruby character on each side.
    float inset = (logicalWidth - maxPreferredLogicalWidth) / (expansionOpportunityCount + 1);
    if (expansionOpportunityCount)
        inset = std::min<float>(2 * style()->fontSize(), inset);

    logicalLeft += inset / 2;
    logicalWidth -= inset;
}

bool RenderRubyText::avoidsFloats() const
{
    return true;
}

} // namespace blink