xref: /external/chromium_org/third_party/WebKit/Source/core/rendering/SubtreeLayoutScope.h

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#ifndef SubtreeLayoutScope_h
#define SubtreeLayoutScope_h

#include "wtf/HashSet.h"

// This is the way to mark a subtree as needing layout during layout,
// e.g. for the purposes of doing a multipass layout.
//
// It should only be used during layout. Outside of layout, you should
// just call renderer->setNeedsLayout() directly.
//
// It ensures that you don't accidentally mark part of the tree as
// needing layout and not actually lay it out.

namespace blink {

class RenderObject;

class SubtreeLayoutScope {
public:
    SubtreeLayoutScope(RenderObject& root);
    ~SubtreeLayoutScope();

    void setNeedsLayout(RenderObject* descendant);
    void setChildNeedsLayout(RenderObject* descendant);

    RenderObject& root() { return m_root; }
    void addRendererToLayout(RenderObject* renderer);

private:
    RenderObject& m_root;

#if ENABLE(ASSERT)
    HashSet<RenderObject*> m_renderersToLayout;
#endif
};

}

#endif