#ifndef _CoherentHierarchicalCullingManager_H__
#define _CoherentHierarchicalCullingManager_H__

#include "CullingManager.h"
#include "HierarchyInterface.h"


namespace GtpVisibility
{

/** Renders the scene with the coherent hierarchical culling algorithm. 
*/
class CoherentHierarchicalCullingManager : public CullingManager
{
public:
	CoherentHierarchicalCullingManager();
	/** Constructor taking the assumed visibility into account, i.e., the estimation
		for how many frames the current visibility is considered to be valid
	*/
	CoherentHierarchicalCullingManager(const unsigned int assumedVisibility);

	void RenderScene();
	
	/** Sets assumed visibility (i.e., an estimation for 
		how many frames the visibility is considered to be valid).
		@param assumedVisibility indicates for how many frames the 
		same visibility is be assumed.
		if 0, the visibility is tested deterministically for each frame.
	*/
	void SetAssumedVisibility(const unsigned int assumedVisibility);	
	/** This is an optimization when issuing the occlusion test. 
		The test is done with actual geometry rather than the bounding 
		box of leave nodes previously marked as visible.

		@param testGeometry if this optimization should be used
		@remark this option is only useful for the coherent hierarchical culling algorithm
	*/
	void SetTestGeometryForVisibleLeaves(const bool testGeometry);
	/** See TestGeometryForVisibleLeaves
	*/
	bool GetTestGeometryForVisibleLeaves();


protected:

	/** Decides if node is considered to be visible depeding on the 
		assumed visibility factor.
		@returns if node is considered to be visible
	*/
	bool DecideVisible(HierarchyNode *node) const;

	/** Skip query for this node.
	*/
	void SkipQuery(HierarchyNode *node) const;

	/** If this node is still valid for traversal in this frame.
		It is possible that the parent was tested invisible before
		so this node can be skipped.
	*/
	bool NodeInvalid(HierarchyNode *node) const;

	void AssignAssumedVisibility(GtpVisibility::HierarchyNode *node);


	//////////////////////

	/** number of steps the visibility is assumed to be valid.
	*/
	unsigned int mAssumedVisibility;

	bool mTestGeometryForVisibleLeaves;

	QueryQueue mQueryQueue;
};

} // namespace GtpVisibility

#endif // CoherentHierarchicalCullingManager_H