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#ifndef RenderLayerStackingNodeIterator_h
#define RenderLayerStackingNodeIterator_h
#include "wtf/Noncopyable.h"
namespace WebCore {
enum ChildrenIteration {
NegativeZOrderChildren = 1,
NormalFlowChildren = 1 << 1,
PositiveZOrderChildren = 1 << 2,
AllChildren = NegativeZOrderChildren | NormalFlowChildren | PositiveZOrderChildren
};
class RenderLayer;
class RenderLayerStackingNode;
// This iterator walks the RenderLayerStackingNode lists in the following order:
// NegativeZOrderChildren -> NormalFlowChildren -> PositiveZOrderChildren.
class RenderLayerStackingNodeIterator {
WTF_MAKE_NONCOPYABLE(RenderLayerStackingNodeIterator);
public:
RenderLayerStackingNodeIterator(const RenderLayerStackingNode& root, unsigned whichChildren)
: m_root(root)
, m_remainingChildren(whichChildren)
, m_index(0)
{
}
RenderLayerStackingNode* next();
private:
const RenderLayerStackingNode& m_root;
unsigned m_remainingChildren;
unsigned m_index;
};
// This iterator is similar to RenderLayerStackingNodeIterator but it walks the lists in reverse order
// (from the last item to the first one).
class RenderLayerStackingNodeReverseIterator {
WTF_MAKE_NONCOPYABLE(RenderLayerStackingNodeReverseIterator);
public:
RenderLayerStackingNodeReverseIterator(const RenderLayerStackingNode& root, unsigned whichChildren)
: m_root(root)
, m_remainingChildren(whichChildren)
{
setIndexToLastItem();
}
RenderLayerStackingNode* next();
private:
void setIndexToLastItem();
const RenderLayerStackingNode& m_root;
unsigned m_remainingChildren;
int m_index;
};
} // namespace WebCore
#endif // RenderLayerStackingNodeIterator_h