Source/core/paint/DeprecatedPaintLayerStackingNodeIterator.cpp

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
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 * in the documentation and/or other materials provided with the
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#include "config.h"
#include "core/paint/DeprecatedPaintLayerStackingNodeIterator.h"

// FIXME: We should build our primitive on top of
// DeprecatedLayerStackingNode and remove this include.
#include "core/paint/DeprecatedPaintLayer.h"
#include "core/paint/DeprecatedPaintLayerStackingNode.h"

namespace blink {

DeprecatedPaintLayerStackingNodeIterator::DeprecatedPaintLayerStackingNodeIterator(const DeprecatedPaintLayerStackingNode& root, unsigned whichChildren)
    : m_root(root)
    , m_remainingChildren(whichChildren)
    , m_index(0)
{
    m_currentNormalFlowChild = root.layer()->firstChild();
}

DeprecatedPaintLayerStackingNode* DeprecatedPaintLayerStackingNodeIterator::next()
{
    if (m_remainingChildren & NegativeZOrderChildren) {
        Vector<DeprecatedPaintLayerStackingNode*>* negZOrderList = m_root.negZOrderList();
        if (negZOrderList && m_index < negZOrderList->size())
            return negZOrderList->at(m_index++);

        m_index = 0;
        m_remainingChildren &= ~NegativeZOrderChildren;
    }

    if (m_remainingChildren & NormalFlowChildren) {
        for (; m_currentNormalFlowChild; m_currentNormalFlowChild = m_currentNormalFlowChild->nextSibling()) {
            if (!m_currentNormalFlowChild->stackingNode()->isTreatedAsStackingContextForPainting() && !m_currentNormalFlowChild->isReflection()) {
                DeprecatedPaintLayer* normalFlowChild = m_currentNormalFlowChild;
                m_currentNormalFlowChild = m_currentNormalFlowChild->nextSibling();
                return normalFlowChild->stackingNode();
            }
        }

        // We reset the iterator in case we reuse it.
        m_currentNormalFlowChild = m_root.layer()->firstChild();
        m_remainingChildren &= ~NormalFlowChildren;
    }

    if (m_remainingChildren & PositiveZOrderChildren) {
        Vector<DeprecatedPaintLayerStackingNode*>* posZOrderList = m_root.posZOrderList();
        if (posZOrderList && m_index < posZOrderList->size())
            return posZOrderList->at(m_index++);

        m_index = 0;
        m_remainingChildren &= ~PositiveZOrderChildren;
    }

    return 0;
}

DeprecatedPaintLayerStackingNode* DeprecatedPaintLayerStackingNodeReverseIterator::next()
{
    if (m_remainingChildren & NegativeZOrderChildren) {
        Vector<DeprecatedPaintLayerStackingNode*>* negZOrderList = m_root.negZOrderList();
        if (negZOrderList && m_index >= 0)
            return negZOrderList->at(m_index--);

        m_remainingChildren &= ~NegativeZOrderChildren;
        setIndexToLastItem();
    }

    if (m_remainingChildren & NormalFlowChildren) {
        for (; m_currentNormalFlowChild; m_currentNormalFlowChild = m_currentNormalFlowChild->previousSibling()) {
            if (!m_currentNormalFlowChild->stackingNode()->isTreatedAsStackingContextForPainting() && !m_currentNormalFlowChild->isReflection()) {
                DeprecatedPaintLayer* normalFlowChild = m_currentNormalFlowChild;
                m_currentNormalFlowChild = m_currentNormalFlowChild->previousSibling();
                return normalFlowChild->stackingNode();
            }
        }

        m_remainingChildren &= ~NormalFlowChildren;
        setIndexToLastItem();
    }

    if (m_remainingChildren & PositiveZOrderChildren) {
        Vector<DeprecatedPaintLayerStackingNode*>* posZOrderList = m_root.posZOrderList();
        if (posZOrderList && m_index >= 0)
            return posZOrderList->at(m_index--);

        m_remainingChildren &= ~PositiveZOrderChildren;
        setIndexToLastItem();
    }

    return 0;
}

void DeprecatedPaintLayerStackingNodeReverseIterator::setIndexToLastItem()
{
    if (m_remainingChildren & NegativeZOrderChildren) {
        Vector<DeprecatedPaintLayerStackingNode*>* negZOrderList = m_root.negZOrderList();
        if (negZOrderList) {
            m_index  = negZOrderList->size() - 1;
            return;
        }

        m_remainingChildren &= ~NegativeZOrderChildren;
    }

    if (m_remainingChildren & NormalFlowChildren) {
        m_currentNormalFlowChild = m_root.layer()->lastChild();
        return;
    }

    if (m_remainingChildren & PositiveZOrderChildren) {
        Vector<DeprecatedPaintLayerStackingNode*>* posZOrderList = m_root.posZOrderList();
        if (posZOrderList) {
            m_index = posZOrderList->size() - 1;
            return;
        }

        m_remainingChildren &= ~PositiveZOrderChildren;
    }

    // No more list to visit.
    ASSERT(!m_remainingChildren);
    m_index = -1;
}

} // namespace blink