kev/Drawer/SSBase/DrawOperator/RTree.h

#ifndef RTREE_H
#define RTREE_H

#pragma push_macro("min")
#undef min

#pragma push_macro("max")
#undef max

// NOTE This file compiles under MSVC 6 SP5 and MSVC .Net 2003 it may not work on other compilers without modification.

// NOTE These next few lines may be win32 specific, you may need to modify them to compile on other platform
#include <stdio.h>
#include <math.h>
#include <assert.h>
#include <stdlib.h>

#include <algorithm>
#include <functional>
#include <vector>
#include <queue>
#include <limits>

#define RTREE_ASSERT assert // RTree uses RTREE_ASSERT( condition )
//#ifdef Min
//#define RTREE_MIN Min
//#else
//#define RTREE_MIN std::min
//#endif //Min
//#ifdef Max
//#define RTREE_MAX Max
//#else
//#define RTREE_MAX std::max
//#endif //Max

template <typename T>
inline const T& RTREE_MIN(const T& a, const T& b) {
	return (a < b) ? a : b;
}

template <typename T>
inline const T& RTREE_MAX(const T& a, const T& b) {
	return (a > b) ? a : b;
}

#ifndef M_PI
	#define M_PI 3.14159265358979323846
#endif

#ifndef M_E
	#define M_E 2.7182818284590452354
#endif

//
// RTree.h
//

#define RTREE_TEMPLATE template<class DATATYPE, class ELEMTYPE, int NUMDIMS, class ELEMTYPEREAL, int TMAXNODES, int TMINNODES>
#define RTREE_QUAL RTree<DATATYPE, ELEMTYPE, NUMDIMS, ELEMTYPEREAL, TMAXNODES, TMINNODES>

#define RTREE_DONT_USE_MEMPOOLS // This version does not contain a fixed memory allocator, fill in lines with EXAMPLE to implement one.
#define RTREE_USE_SPHERICAL_VOLUME // Better split classification, may be slower on some systems

// Fwd decl
class RTFileStream;  // File I/O helper class, look below for implementation and notes.


/// \class RTree
/// Implementation of RTree, a multidimensional bounding rectangle tree.
/// Example usage: For a 3-dimensional tree use RTree<Object*, float, 3> myTree;
///
/// This modified, templated C++ version by Greg Douglas at Auran (http://www.auran.com)
///
/// DATATYPE Referenced data, should be int, void*, obj* etc. no larger than sizeof<void*> and simple type
/// ELEMTYPE Type of element such as int or float
/// NUMDIMS Number of dimensions such as 2 or 3
/// ELEMTYPEREAL Type of element that allows fractional and large values such as float or double, for use in volume calcs
///
/// NOTES: Inserting and removing data requires the knowledge of its constant Minimal Bounding Rectangle.
///        This version uses new/delete for nodes, I recommend using a fixed size allocator for efficiency.
///        Instead of using a callback function for returned results, I recommend and efficient pre-sized, grow-only memory
///        array similar to MFC CArray or STL Vector for returning search query result.
///
template<class DATATYPE, class ELEMTYPE, int NUMDIMS,
	class ELEMTYPEREAL = ELEMTYPE, int TMAXNODES = 8, int TMINNODES = TMAXNODES / 2>
	class RTree
{
	static_assert(std::numeric_limits<ELEMTYPEREAL>::is_iec559, "'ELEMTYPEREAL' accepts floating-point types only");

protected:

	struct Node;  // Fwd decl.  Used by other internal structs and iterator

public:

	// These constant must be declared after Branch and before Node struct
	// Stuck up here for MSVC 6 compiler.  NSVC .NET 2003 is much happier.
	enum
	{
		MAXNODES = TMAXNODES,                         ///< Max elements in node
		MINNODES = TMINNODES,                         ///< Min elements in node
	};

public:

	RTree();
	RTree(const RTree& other);
	virtual ~RTree();

	/// Insert entry
	/// \param a_min Min of bounding rect
	/// \param a_max Max of bounding rect
	/// \param a_dataId Positive Id of data.  Maybe zero, but negative numbers not allowed.
	void Insert(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], const DATATYPE& a_dataId);

	/// Remove entry (traverse the whole tree and removes every occurrence)
	/// \param a_dataId Positive Id of data.  Maybe zero, but negative numbers not allowed.
	void Remove(const DATATYPE& a_dataId);

	/// Remove entry (only if inside the given rect)
	/// \param a_min Min of bounding rect
	/// \param a_max Max of bounding rect
	/// \param a_dataId Positive Id of data.  Maybe zero, but negative numbers not allowed.
	void Remove(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], const DATATYPE& a_dataId);

	/// Find all within search rectangle
	/// \param a_min Min of search bounding rect
	/// \param a_max Max of search bounding rect
	/// \param a_searchResult Search result array.  Caller should set grow size. Function will reset, not append to array.
	/// \param a_resultCallback Callback function to return result.  Callback should return 'true' to continue searching
	/// \param a_context User context to pass as parameter to a_resultCallback
	/// \return Returns the number of entries found
	int Search(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], std::function<bool(const DATATYPE&)> callback) const;

	/// Find the nearest neighbors
	/// \param a_min Min of search bounding rect
	/// \param a_max Max of search bounding rect
	/// \param a_resultCallback Callback function to return result.  The Callback takes both the resulting data point and the calculated square distance. Callback should return 'true' to continue searching
	/// \return Returns the number of entries found
	size_t NNSearch(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], std::function<bool(const DATATYPE&, ELEMTYPE)> callback) const;


	/// Remove all entries from tree
	void RemoveAll();

	/// Count the data elements in this container.  This is slow as no internal counter is maintained.
	int Count();

	/// Load tree contents from file
	bool Load(const char* a_fileName);
	/// Load tree contents from stream
	bool Load(RTFileStream& a_stream);


	/// Save tree contents to file
	bool Save(const char* a_fileName);
	/// Save tree contents to stream
	bool Save(RTFileStream& a_stream);

	/// Iterator is not remove safe.
	class Iterator
	{
	private:

		enum { MAX_STACK = 32 }; //  Max stack size. Allows almost n^32 where n is number of branches in node

		struct StackElement
		{
			Node* m_node;
			int m_branchIndex;
		};

	public:

		Iterator() { Init(); }

		~Iterator() { }

		/// Is iterator invalid
		bool IsNull() { return (m_tos <= 0); }

		/// Is iterator pointing to valid data
		bool IsNotNull() { return (m_tos > 0); }

		/// Access the current data element. Caller must be sure iterator is not NULL first.
		DATATYPE& operator*()
		{
			RTREE_ASSERT(IsNotNull());
			StackElement& curTos = m_stack[m_tos - 1];
			return curTos.m_node->m_branch[curTos.m_branchIndex].m_data;
		}

		/// Access the current data element. Caller must be sure iterator is not NULL first.
		const DATATYPE& operator*() const
		{
			RTREE_ASSERT(IsNotNull());
			StackElement& curTos = m_stack[m_tos - 1];
			return curTos.m_node->m_branch[curTos.m_branchIndex].m_data;
		}

		/// Find the next data element
		bool operator++() { return FindNextData(); }

		/// Get the bounds for this node
		void GetBounds(ELEMTYPE a_min[NUMDIMS], ELEMTYPE a_max[NUMDIMS])
		{
			RTREE_ASSERT(IsNotNull());
			StackElement& curTos = m_stack[m_tos - 1];
			Branch& curBranch = curTos.m_node->m_branch[curTos.m_branchIndex];

			for (int index = 0; index < NUMDIMS; ++index)
			{
				a_min[index] = curBranch.m_rect.m_min[index];
				a_max[index] = curBranch.m_rect.m_max[index];
			}
		}

	private:

		/// Reset iterator
		void Init() { m_tos = 0; }

		/// Find the next data element in the tree (For internal use only)
		bool FindNextData()
		{
			for (;;)
			{
				if (m_tos <= 0)
				{
					return false;
				}
				StackElement curTos = Pop(); // Copy stack top cause it may change as we use it

				if (curTos.m_node->IsLeaf())
				{
					// Keep walking through data while we can
					if (curTos.m_branchIndex + 1 < curTos.m_node->m_count)
					{
						// There is more data, just point to the next one
						Push(curTos.m_node, curTos.m_branchIndex + 1);
						return true;
					}
					// No more data, so it will fall back to previous level
				}
				else
				{
					if (curTos.m_branchIndex + 1 < curTos.m_node->m_count)
					{
						// Push sibling on for future tree walk
						// This is the 'fall back' node when we finish with the current level
						Push(curTos.m_node, curTos.m_branchIndex + 1);
					}
					// Since cur node is not a leaf, push first of next level to get deeper into the tree
					Node* nextLevelnode = curTos.m_node->m_branch[curTos.m_branchIndex].m_child;
					Push(nextLevelnode, 0);

					// If we pushed on a new leaf, exit as the data is ready at TOS
					if (nextLevelnode->IsLeaf())
					{
						return true;
					}
				}
			}
		}

		/// Push node and branch onto iteration stack (For internal use only)
		void Push(Node* a_node, int a_branchIndex)
		{
			m_stack[m_tos].m_node = a_node;
			m_stack[m_tos].m_branchIndex = a_branchIndex;
			++m_tos;
			RTREE_ASSERT(m_tos <= MAX_STACK);
		}

		/// Pop element off iteration stack (For internal use only)
		StackElement& Pop()
		{
			RTREE_ASSERT(m_tos > 0);
			--m_tos;
			return m_stack[m_tos];
		}

		StackElement m_stack[MAX_STACK];              ///< Stack as we are doing iteration instead of recursion
		int m_tos;                                    ///< Top Of Stack index

		friend class RTree; // Allow hiding of non-public functions while allowing manipulation by logical owner
	};

	/// Get 'first' for iteration
	void GetFirst(Iterator& a_it)
	{
		a_it.Init();
		Node* first = m_root;
		while (first)
		{
			if (first->IsInternalNode() && first->m_count > 1)
			{
				a_it.Push(first, 1); // Descend sibling branch later
			}
			else if (first->IsLeaf())
			{
				if (first->m_count)
				{
					a_it.Push(first, 0);
				}
				break;
			}
			first = first->m_branch[0].m_child;
		}
	}

	/// Get Next for iteration
	void GetNext(Iterator& a_it) { ++a_it; }

	/// Is iterator NULL, or at end?
	bool IsNull(Iterator& a_it) { return a_it.IsNull(); }

	/// Get object at iterator position
	DATATYPE& GetAt(Iterator& a_it) { return *a_it; }

protected:

	/// Minimal bounding rectangle (n-dimensional)
	struct Rect
	{
		ELEMTYPE m_min[NUMDIMS];                      ///< Min dimensions of bounding box
		ELEMTYPE m_max[NUMDIMS];                      ///< Max dimensions of bounding box
	};

	/// May be data or may be another subtree
	/// The parents level determines this.
	/// If the parents level is 0, then this is data
	struct Branch
	{
		Rect m_rect;                                  ///< Bounds
		Node* m_child = NULL;                         ///< Child node
		DATATYPE m_data;                              ///< Data Id
	};

	/// Node for each branch level
	struct Node
	{
		bool IsInternalNode() { return (m_level > 0); } // Not a leaf, but a internal node
		bool IsLeaf() { return (m_level == 0); } // A leaf, contains data

		int m_count;                                  ///< Count
		int m_level;                                  ///< Leaf is zero, others positive
		Branch m_branch[MAXNODES];                    ///< Branch
	};

	/// A link list of nodes for reinsertion after a delete operation
	struct ListNode
	{
		ListNode* m_next;                             ///< Next in list
		Node* m_node;                                 ///< Node
	};

	/// Variables for finding a split partition
	struct PartitionVars
	{
		enum { NOT_TAKEN = -1 }; // indicates that position

		int m_partition[MAXNODES + 1];
		int m_total;
		int m_minFill;
		int m_count[2];
		Rect m_cover[2];
		ELEMTYPEREAL m_area[2];

		Branch m_branchBuf[MAXNODES + 1];
		int m_branchCount;
		Rect m_coverSplit;
		ELEMTYPEREAL m_coverSplitArea;
	};

	Node* AllocNode();
	void FreeNode(Node* a_node);
	void InitNode(Node* a_node);
	void InitRect(Rect* a_rect);
	bool InsertRectRec(const Branch& a_branch, Node* a_node, Node** a_newNode, int a_level);
	bool InsertRect(const Branch& a_branch, Node** a_root, int a_level);
	Rect NodeCover(Node* a_node);
	bool AddBranch(const Branch* a_branch, Node* a_node, Node** a_newNode);
	void DisconnectBranch(Node* a_node, int a_index);
	int PickBranch(const Rect* a_rect, Node* a_node);
	Rect CombineRect(const Rect* a_rectA, const Rect* a_rectB);
	void SplitNode(Node* a_node, const Branch* a_branch, Node** a_newNode);
	ELEMTYPEREAL RectSphericalVolume(Rect* a_rect);
	ELEMTYPEREAL RectVolume(Rect* a_rect);
	ELEMTYPEREAL CalcRectVolume(Rect* a_rect);
	void GetBranches(Node* a_node, const Branch* a_branch, PartitionVars* a_parVars);
	void ChoosePartition(PartitionVars* a_parVars, int a_minFill);
	void LoadNodes(Node* a_nodeA, Node* a_nodeB, PartitionVars* a_parVars);
	void InitParVars(PartitionVars* a_parVars, int a_maxRects, int a_minFill);
	void PickSeeds(PartitionVars* a_parVars);
	void Classify(int a_index, int a_group, PartitionVars* a_parVars);
	bool RemoveRect(Rect* a_rect, const DATATYPE& a_id, Node** a_root);
	bool RemoveRectRec(Rect* a_rect, const DATATYPE& a_id, Node* a_node, ListNode** a_listNode);
	ListNode* AllocListNode();
	void FreeListNode(ListNode* a_listNode);
	bool Overlap(Rect* a_rectA, Rect* a_rectB) const;
	ELEMTYPE SquareDistance(Rect const& a_rectA, Rect const& a_rectB) const;
	void ReInsert(Node* a_node, ListNode** a_listNode);
	bool Search(Node* a_node, Rect* a_rect, int& a_foundCount, std::function<bool(const DATATYPE&)> callback) const;
	void RemoveAllRec(Node* a_node);
	void Reset();
	void CountRec(Node* a_node, int& a_count);

	bool SaveRec(Node* a_node, RTFileStream& a_stream);
	bool LoadRec(Node* a_node, RTFileStream& a_stream);
	void CopyRec(Node* current, Node* other);

	Node* m_root;                                    ///< Root of tree
	ELEMTYPEREAL m_unitSphereVolume;                 ///< Unit sphere constant for required number of dimensions

public:
	// return all the AABBs that form the RTree
	std::vector<Rect> ListTree() const;
};


// Because there is not stream support, this is a quick and dirty file I/O helper.
// Users will likely replace its usage with a Stream implementation from their favorite API.
class RTFileStream
{
	FILE* m_file;

public:


	RTFileStream()
	{
		m_file = NULL;
	}

	~RTFileStream()
	{
		Close();
	}

	bool Open(const char* a_fileName, const char* mode)
	{
#if defined(_WIN32) && defined(__STDC_WANT_SECURE_LIB__)
		return fopen_s(&m_file, a_fileName, mode) == 0;
#else
		m_file = fopen(a_fileName, mode);
		return m_file != nullptr;
#endif
	}

	bool OpenRead(const char* a_fileName)
	{
		return this->Open(a_fileName, "rb");
	}

	bool OpenWrite(const char* a_fileName)
	{
		return this->Open(a_fileName, "wb");
	}

	void Close()
	{
		if (m_file)
		{
			fclose(m_file);
			m_file = NULL;
		}
	}

	template< typename TYPE >
	size_t Write(const TYPE& a_value)
	{
		RTREE_ASSERT(m_file);
		return fwrite((void*)&a_value, sizeof(a_value), 1, m_file);
	}

	template< typename TYPE >
	size_t WriteArray(const TYPE* a_array, int a_count)
	{
		RTREE_ASSERT(m_file);
		return fwrite((void*)a_array, sizeof(TYPE) * a_count, 1, m_file);
	}

	template< typename TYPE >
	size_t Read(TYPE& a_value)
	{
		RTREE_ASSERT(m_file);
		return fread((void*)&a_value, sizeof(a_value), 1, m_file);
	}

	template< typename TYPE >
	size_t ReadArray(TYPE* a_array, int a_count)
	{
		RTREE_ASSERT(m_file);
		return fread((void*)a_array, sizeof(TYPE) * a_count, 1, m_file);
	}
};


RTREE_TEMPLATE
RTREE_QUAL::RTree()
{
	RTREE_ASSERT(MAXNODES > MINNODES);
	RTREE_ASSERT(MINNODES > 0);

	// Precomputed volumes of the unit spheres for the first few dimensions
	const float UNIT_SPHERE_VOLUMES[] = {
	  0.000000f, 2.000000f, 3.141593f, // Dimension  0,1,2
	  4.188790f, 4.934802f, 5.263789f, // Dimension  3,4,5
	  5.167713f, 4.724766f, 4.058712f, // Dimension  6,7,8
	  3.298509f, 2.550164f, 1.884104f, // Dimension  9,10,11
	  1.335263f, 0.910629f, 0.599265f, // Dimension  12,13,14
	  0.381443f, 0.235331f, 0.140981f, // Dimension  15,16,17
	  0.082146f, 0.046622f, 0.025807f, // Dimension  18,19,20
	};

	m_root = AllocNode();
	m_root->m_level = 0;

	if (NUMDIMS < 21)
	{
		m_unitSphereVolume = (ELEMTYPEREAL)UNIT_SPHERE_VOLUMES[NUMDIMS];
	}
	else {
		// Stirling's approximation, applicable to high dimensions
		// https://en.wikipedia.org/wiki/Volume_of_an_n-ball#Approximation_for_high_dimensions
		m_unitSphereVolume = (ELEMTYPEREAL)(1.0 / std::sqrt(NUMDIMS * M_PI) *
			std::pow(2 * M_PI * M_E / NUMDIMS, NUMDIMS / 2.0));
	}
}


RTREE_TEMPLATE
RTREE_QUAL::RTree(const RTree& other) : RTree()
{
	CopyRec(m_root, other.m_root);
}


RTREE_TEMPLATE
RTREE_QUAL::~RTree()
{
	Reset(); // Free, or reset node memory
}


RTREE_TEMPLATE
void RTREE_QUAL::Insert(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], const DATATYPE& a_dataId)
{
#ifdef _DEBUG
	for (int index = 0; index < NUMDIMS; ++index)
	{
		RTREE_ASSERT(a_min[index] <= a_max[index]);
	}
#endif //_DEBUG

	Branch branch;
	branch.m_data = a_dataId;
	branch.m_child = NULL;

	for (int axis = 0; axis < NUMDIMS; ++axis)
	{
		branch.m_rect.m_min[axis] = a_min[axis];
		branch.m_rect.m_max[axis] = a_max[axis];
	}

	InsertRect(branch, &m_root, 0);
}


RTREE_TEMPLATE
void RTREE_QUAL::Remove(const DATATYPE& a_dataId)
{
	RemoveRect(NULL, a_dataId, &m_root);
}


RTREE_TEMPLATE
void RTREE_QUAL::Remove(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], const DATATYPE& a_dataId)
{
#ifdef _DEBUG
	for (int index = 0; index < NUMDIMS; ++index)
	{
		RTREE_ASSERT(a_min[index] <= a_max[index]);
	}
#endif //_DEBUG

	Rect rect;

	for (int axis = 0; axis < NUMDIMS; ++axis)
	{
		rect.m_min[axis] = a_min[axis];
		rect.m_max[axis] = a_max[axis];
	}

	RemoveRect(&rect, a_dataId, &m_root);
}


RTREE_TEMPLATE
int RTREE_QUAL::Search(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], std::function<bool(const DATATYPE&)> callback) const
{
#ifdef _DEBUG
	for (int index = 0; index < NUMDIMS; ++index)
	{
		RTREE_ASSERT(a_min[index] <= a_max[index]);
	}
#endif //_DEBUG

	Rect rect;

	for (int axis = 0; axis < NUMDIMS; ++axis)
	{
		rect.m_min[axis] = a_min[axis];
		rect.m_max[axis] = a_max[axis];
	}

	// NOTE: May want to return search result another way, perhaps returning the number of found elements here.

	int foundCount = 0;
	Search(m_root, &rect, foundCount, callback);

	return foundCount;
}

RTREE_TEMPLATE
size_t RTREE_QUAL::NNSearch(
	const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS],
	std::function<bool(const DATATYPE&, ELEMTYPE)> callback
) const
{
	// Create a search rectangle
	Rect rect;
	for (int axis = 0; axis < NUMDIMS; ++axis)
	{
		rect.m_min[axis] = a_min[axis];
		rect.m_max[axis] = a_max[axis];
	}

	// class to store branches in the priority queue
	struct QueueItem
	{
		QueueItem(Branch* branch, ELEMTYPE distance) :
			branch(branch),
			distance(distance)
		{}

		// Sort in the queue with the minimum distance
		// taking priority
		bool operator<(QueueItem const& a) const
		{
			return this->distance > a.distance;
		}

		Branch* branch;
		ELEMTYPE distance;
	};

	std::priority_queue<QueueItem> search_queue;

	// All branches in the root node are inserted into the priority queue. 
	for (auto i = 0; i < m_root->m_count; ++i)
	{
		auto d = this->SquareDistance(rect, m_root->m_branch[i].m_rect);
		search_queue.emplace(m_root->m_branch + i, d);
	}

	size_t foundCount = 0;

	// Until the queue is empty
	while (!search_queue.empty())
	{
		// Process the top item in the queue
		auto process = std::move(search_queue.top());
		search_queue.pop();

		if (process.branch->m_child)
		{
			// If the branch has children, add them all into the queue
			Node* node = process.branch->m_child;
			for (auto i = 0; i < node->m_count; ++i)
			{
				auto d = this->SquareDistance(rect, node->m_branch[i].m_rect);
				search_queue.emplace(node->m_branch + i, d);
			}
		}
		else
		{
			// If this is a leaf, then we have found a minimum distance
			// Call the callback
			++foundCount;
			if (!callback(process.branch->m_data, process.distance))
			{
				// If the user has flaged to stopped, then return
				// the number found.
				return foundCount;
			}
		}

	}

	// No more items to search
	return foundCount;
}


RTREE_TEMPLATE
int RTREE_QUAL::Count()
{
	int count = 0;
	CountRec(m_root, count);

	return count;
}



RTREE_TEMPLATE
void RTREE_QUAL::CountRec(Node* a_node, int& a_count)
{
	if (a_node->IsInternalNode())  // not a leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			CountRec(a_node->m_branch[index].m_child, a_count);
		}
	}
	else // A leaf node
	{
		a_count += a_node->m_count;
	}
}


RTREE_TEMPLATE
bool RTREE_QUAL::Load(const char* a_fileName)
{
	RemoveAll(); // Clear existing tree

	RTFileStream stream;
	if (!stream.OpenRead(a_fileName))
	{
		return false;
	}

	bool result = Load(stream);

	stream.Close();

	return result;
}



RTREE_TEMPLATE
bool RTREE_QUAL::Load(RTFileStream& a_stream)
{
	// Write some kind of header
	int _dataFileId = ('R' << 0) | ('T' << 8) | ('R' << 16) | ('E' << 24);
	int _dataSize = sizeof(DATATYPE);
	int _dataNumDims = NUMDIMS;
	int _dataElemSize = sizeof(ELEMTYPE);
	int _dataElemRealSize = sizeof(ELEMTYPEREAL);
	int _dataMaxNodes = TMAXNODES;
	int _dataMinNodes = TMINNODES;

	int dataFileId = 0;
	int dataSize = 0;
	int dataNumDims = 0;
	int dataElemSize = 0;
	int dataElemRealSize = 0;
	int dataMaxNodes = 0;
	int dataMinNodes = 0;

	a_stream.Read(dataFileId);
	a_stream.Read(dataSize);
	a_stream.Read(dataNumDims);
	a_stream.Read(dataElemSize);
	a_stream.Read(dataElemRealSize);
	a_stream.Read(dataMaxNodes);
	a_stream.Read(dataMinNodes);

	bool result = false;

	// Test if header was valid and compatible
	if ((dataFileId == _dataFileId)
		&& (dataSize == _dataSize)
		&& (dataNumDims == _dataNumDims)
		&& (dataElemSize == _dataElemSize)
		&& (dataElemRealSize == _dataElemRealSize)
		&& (dataMaxNodes == _dataMaxNodes)
		&& (dataMinNodes == _dataMinNodes)
		)
	{
		// Recursively load tree
		result = LoadRec(m_root, a_stream);
	}

	return result;
}


RTREE_TEMPLATE
bool RTREE_QUAL::LoadRec(Node* a_node, RTFileStream& a_stream)
{
	a_stream.Read(a_node->m_level);
	a_stream.Read(a_node->m_count);

	if (a_node->IsInternalNode())  // not a leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			Branch* curBranch = &a_node->m_branch[index];

			a_stream.ReadArray(curBranch->m_rect.m_min, NUMDIMS);
			a_stream.ReadArray(curBranch->m_rect.m_max, NUMDIMS);

			curBranch->m_child = AllocNode();
			LoadRec(curBranch->m_child, a_stream);
		}
	}
	else // A leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			Branch* curBranch = &a_node->m_branch[index];

			a_stream.ReadArray(curBranch->m_rect.m_min, NUMDIMS);
			a_stream.ReadArray(curBranch->m_rect.m_max, NUMDIMS);

			a_stream.Read(curBranch->m_data);
		}
	}

	return true; // Should do more error checking on I/O operations
}


RTREE_TEMPLATE
void RTREE_QUAL::CopyRec(Node* current, Node* other)
{
	current->m_level = other->m_level;
	current->m_count = other->m_count;

	if (current->IsInternalNode())  // not a leaf node
	{
		for (int index = 0; index < current->m_count; ++index)
		{
			Branch* currentBranch = &current->m_branch[index];
			Branch* otherBranch = &other->m_branch[index];

			std::copy(otherBranch->m_rect.m_min,
				otherBranch->m_rect.m_min + NUMDIMS,
				currentBranch->m_rect.m_min);

			std::copy(otherBranch->m_rect.m_max,
				otherBranch->m_rect.m_max + NUMDIMS,
				currentBranch->m_rect.m_max);

			currentBranch->m_child = AllocNode();
			CopyRec(currentBranch->m_child, otherBranch->m_child);
		}
	}
	else // A leaf node
	{
		for (int index = 0; index < current->m_count; ++index)
		{
			Branch* currentBranch = &current->m_branch[index];
			Branch* otherBranch = &other->m_branch[index];

			std::copy(otherBranch->m_rect.m_min,
				otherBranch->m_rect.m_min + NUMDIMS,
				currentBranch->m_rect.m_min);

			std::copy(otherBranch->m_rect.m_max,
				otherBranch->m_rect.m_max + NUMDIMS,
				currentBranch->m_rect.m_max);

			currentBranch->m_data = otherBranch->m_data;
		}
	}
}


RTREE_TEMPLATE
bool RTREE_QUAL::Save(const char* a_fileName)
{
	RTFileStream stream;
	if (!stream.OpenWrite(a_fileName))
	{
		return false;
	}

	bool result = Save(stream);

	stream.Close();

	return result;
}


RTREE_TEMPLATE
bool RTREE_QUAL::Save(RTFileStream& a_stream)
{
	// Write some kind of header
	int dataFileId = ('R' << 0) | ('T' << 8) | ('R' << 16) | ('E' << 24);
	int dataSize = sizeof(DATATYPE);
	int dataNumDims = NUMDIMS;
	int dataElemSize = sizeof(ELEMTYPE);
	int dataElemRealSize = sizeof(ELEMTYPEREAL);
	int dataMaxNodes = TMAXNODES;
	int dataMinNodes = TMINNODES;

	a_stream.Write(dataFileId);
	a_stream.Write(dataSize);
	a_stream.Write(dataNumDims);
	a_stream.Write(dataElemSize);
	a_stream.Write(dataElemRealSize);
	a_stream.Write(dataMaxNodes);
	a_stream.Write(dataMinNodes);

	// Recursively save tree
	bool result = SaveRec(m_root, a_stream);

	return result;
}


RTREE_TEMPLATE
bool RTREE_QUAL::SaveRec(Node* a_node, RTFileStream& a_stream)
{
	a_stream.Write(a_node->m_level);
	a_stream.Write(a_node->m_count);

	if (a_node->IsInternalNode())  // not a leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			Branch* curBranch = &a_node->m_branch[index];

			a_stream.WriteArray(curBranch->m_rect.m_min, NUMDIMS);
			a_stream.WriteArray(curBranch->m_rect.m_max, NUMDIMS);

			SaveRec(curBranch->m_child, a_stream);
		}
	}
	else // A leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			Branch* curBranch = &a_node->m_branch[index];

			a_stream.WriteArray(curBranch->m_rect.m_min, NUMDIMS);
			a_stream.WriteArray(curBranch->m_rect.m_max, NUMDIMS);

			a_stream.Write(curBranch->m_data);
		}
	}

	return true; // Should do more error checking on I/O operations
}


RTREE_TEMPLATE
void RTREE_QUAL::RemoveAll()
{
	// Delete all existing nodes
	Reset();

	m_root = AllocNode();
	m_root->m_level = 0;
}


RTREE_TEMPLATE
void RTREE_QUAL::Reset()
{
#ifdef RTREE_DONT_USE_MEMPOOLS
	// Delete all existing nodes
	RemoveAllRec(m_root);
#else // RTREE_DONT_USE_MEMPOOLS
	// Just reset memory pools.  We are not using complex types
	// EXAMPLE
#endif // RTREE_DONT_USE_MEMPOOLS
}


RTREE_TEMPLATE
void RTREE_QUAL::RemoveAllRec(Node* a_node)
{
	RTREE_ASSERT(a_node);
	RTREE_ASSERT(a_node->m_level >= 0);

	if (a_node->IsInternalNode()) // This is an internal node in the tree
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			RemoveAllRec(a_node->m_branch[index].m_child);
		}
	}
	FreeNode(a_node);
}


RTREE_TEMPLATE
typename RTREE_QUAL::Node* RTREE_QUAL::AllocNode()
{
	Node* newNode;
#ifdef RTREE_DONT_USE_MEMPOOLS
	newNode = new Node;
#else // RTREE_DONT_USE_MEMPOOLS
	// EXAMPLE
#endif // RTREE_DONT_USE_MEMPOOLS
	InitNode(newNode);
	return newNode;
}


RTREE_TEMPLATE
void RTREE_QUAL::FreeNode(Node* a_node)
{
	RTREE_ASSERT(a_node);

#ifdef RTREE_DONT_USE_MEMPOOLS
	delete a_node;
#else // RTREE_DONT_USE_MEMPOOLS
	// EXAMPLE
#endif // RTREE_DONT_USE_MEMPOOLS
}


// Allocate space for a node in the list used in DeletRect to
// store Nodes that are too empty.
RTREE_TEMPLATE
typename RTREE_QUAL::ListNode* RTREE_QUAL::AllocListNode()
{
#ifdef RTREE_DONT_USE_MEMPOOLS
	return new ListNode;
#else // RTREE_DONT_USE_MEMPOOLS
	// EXAMPLE
#endif // RTREE_DONT_USE_MEMPOOLS
}


RTREE_TEMPLATE
void RTREE_QUAL::FreeListNode(ListNode* a_listNode)
{
#ifdef RTREE_DONT_USE_MEMPOOLS
	delete a_listNode;
#else // RTREE_DONT_USE_MEMPOOLS
	// EXAMPLE
#endif // RTREE_DONT_USE_MEMPOOLS
}


RTREE_TEMPLATE
void RTREE_QUAL::InitNode(Node* a_node)
{
	a_node->m_count = 0;
	a_node->m_level = -1;
}


RTREE_TEMPLATE
void RTREE_QUAL::InitRect(Rect* a_rect)
{
	for (int index = 0; index < NUMDIMS; ++index)
	{
		a_rect->m_min[index] = (ELEMTYPE)0;
		a_rect->m_max[index] = (ELEMTYPE)0;
	}
}


// Inserts a new data rectangle into the index structure.
// Recursively descends tree, propagates splits back up.
// Returns 0 if node was not split.  Old node updated.
// If node was split, returns 1 and sets the pointer pointed to by
// new_node to point to the new node.  Old node updated to become one of two.
// The level argument specifies the number of steps up from the leaf
// level to insert; e.g. a data rectangle goes in at level = 0.
RTREE_TEMPLATE
bool RTREE_QUAL::InsertRectRec(const Branch& a_branch, Node* a_node, Node** a_newNode, int a_level)
{
	RTREE_ASSERT(a_node && a_newNode);
	RTREE_ASSERT(a_level >= 0 && a_level <= a_node->m_level);

	// recurse until we reach the correct level for the new record. data records
	// will always be called with a_level == 0 (leaf)
	if (a_node->m_level > a_level)
	{
		// Still above level for insertion, go down tree recursively
		Node* otherNode;

		// find the optimal branch for this record
		int index = PickBranch(&a_branch.m_rect, a_node);

		// recursively insert this record into the picked branch
		bool childWasSplit = InsertRectRec(a_branch, a_node->m_branch[index].m_child, &otherNode, a_level);

		if (!childWasSplit)
		{
			// Child was not split. Merge the bounding box of the new record with the
			// existing bounding box
			a_node->m_branch[index].m_rect = CombineRect(&a_branch.m_rect, &(a_node->m_branch[index].m_rect));
			return false;
		}
		else
		{
			// Child was split. The old branches are now re-partitioned to two nodes
			// so we have to re-calculate the bounding boxes of each node
			a_node->m_branch[index].m_rect = NodeCover(a_node->m_branch[index].m_child);
			Branch branch;
			branch.m_child = otherNode;
			branch.m_rect = NodeCover(otherNode);

			// The old node is already a child of a_node. Now add the newly-created
			// node to a_node as well. a_node might be split because of that.
			return AddBranch(&branch, a_node, a_newNode);
		}
	}
	else if (a_node->m_level == a_level)
	{
		// We have reached level for insertion. Add rect, split if necessary
		return AddBranch(&a_branch, a_node, a_newNode);
	}
	else
	{
		// Should never occur
		RTREE_ASSERT(0);
		return false;
	}
}


// Insert a data rectangle into an index structure.
// InsertRect provides for splitting the root;
// returns 1 if root was split, 0 if it was not.
// The level argument specifies the number of steps up from the leaf
// level to insert; e.g. a data rectangle goes in at level = 0.
// InsertRect2 does the recursion.
//
RTREE_TEMPLATE
bool RTREE_QUAL::InsertRect(const Branch& a_branch, Node** a_root, int a_level)
{
	RTREE_ASSERT(a_root);
	RTREE_ASSERT(a_level >= 0 && a_level <= (*a_root)->m_level);
#ifdef _DEBUG
	for (int index = 0; index < NUMDIMS; ++index)
	{
		RTREE_ASSERT(a_branch.m_rect.m_min[index] <= a_branch.m_rect.m_max[index]);
	}
#endif //_DEBUG

	Node* newNode;

	if (InsertRectRec(a_branch, *a_root, &newNode, a_level))  // Root split
	{
		// Grow tree taller and new root
		Node* newRoot = AllocNode();
		newRoot->m_level = (*a_root)->m_level + 1;

		Branch branch;

		// add old root node as a child of the new root
		branch.m_rect = NodeCover(*a_root);
		branch.m_child = *a_root;
		AddBranch(&branch, newRoot, NULL);

		// add the split node as a child of the new root
		branch.m_rect = NodeCover(newNode);
		branch.m_child = newNode;
		AddBranch(&branch, newRoot, NULL);

		// set the new root as the root node
		*a_root = newRoot;

		return true;
	}

	return false;
}


// Find the smallest rectangle that includes all rectangles in branches of a node.
RTREE_TEMPLATE
typename RTREE_QUAL::Rect RTREE_QUAL::NodeCover(Node* a_node)
{
	RTREE_ASSERT(a_node);

	Rect rect = a_node->m_branch[0].m_rect;
	for (int index = 1; index < a_node->m_count; ++index)
	{
		rect = CombineRect(&rect, &(a_node->m_branch[index].m_rect));
	}

	return rect;
}


// Add a branch to a node.  Split the node if necessary.
// Returns 0 if node not split.  Old node updated.
// Returns 1 if node split, sets *new_node to address of new node.
// Old node updated, becomes one of two.
RTREE_TEMPLATE
bool RTREE_QUAL::AddBranch(const Branch* a_branch, Node* a_node, Node** a_newNode)
{
	RTREE_ASSERT(a_branch);
	RTREE_ASSERT(a_node);

	if (a_node->m_count < MAXNODES)  // Split won't be necessary
	{
		a_node->m_branch[a_node->m_count] = *a_branch;
		++a_node->m_count;

		return false;
	}
	else
	{
		RTREE_ASSERT(a_newNode);

		SplitNode(a_node, a_branch, a_newNode);
		return true;
	}
}


// Disconnect a dependent node.
// Caller must return (or stop using iteration index) after this as count has changed
RTREE_TEMPLATE
void RTREE_QUAL::DisconnectBranch(Node* a_node, int a_index)
{
	RTREE_ASSERT(a_node && (a_index >= 0) && (a_index < MAXNODES));
	RTREE_ASSERT(a_node->m_count > 0);

	// Remove element by swapping with the last element to prevent gaps in array
	a_node->m_branch[a_index] = a_node->m_branch[a_node->m_count - 1];

	--a_node->m_count;
}


// Pick a branch.  Pick the one that will need the smallest increase
// in area to accomodate the new rectangle.  This will result in the
// least total area for the covering rectangles in the current node.
// In case of a tie, pick the one which was smaller before, to get
// the best resolution when searching.
RTREE_TEMPLATE
int RTREE_QUAL::PickBranch(const Rect* a_rect, Node* a_node)
{
	RTREE_ASSERT(a_rect && a_node);

	bool firstTime = true;
	ELEMTYPEREAL increase;
	ELEMTYPEREAL bestIncr = (ELEMTYPEREAL)-1;
	ELEMTYPEREAL area;
	ELEMTYPEREAL bestArea = (ELEMTYPEREAL)-1;
	int best = 0;
	Rect tempRect;

	for (int index = 0; index < a_node->m_count; ++index)
	{
		Rect* curRect = &a_node->m_branch[index].m_rect;
		area = CalcRectVolume(curRect);
		tempRect = CombineRect(a_rect, curRect);
		increase = CalcRectVolume(&tempRect) - area;
		if ((increase < bestIncr) || firstTime)
		{
			best = index;
			bestArea = area;
			bestIncr = increase;
			firstTime = false;
		}
		else if ((increase == bestIncr) && (area < bestArea))
		{
			best = index;
			bestArea = area;
			bestIncr = increase;
		}
	}
	return best;
}


// Combine two rectangles into larger one containing both
RTREE_TEMPLATE
typename RTREE_QUAL::Rect RTREE_QUAL::CombineRect(const Rect* a_rectA, const Rect* a_rectB)
{
	RTREE_ASSERT(a_rectA && a_rectB);

	Rect newRect;

	for (int index = 0; index < NUMDIMS; ++index)
	{
		newRect.m_min[index] = RTREE_MIN(a_rectA->m_min[index], a_rectB->m_min[index]);
		newRect.m_max[index] = RTREE_MAX(a_rectA->m_max[index], a_rectB->m_max[index]);
	}

	return newRect;
}



// Split a node.
// Divides the nodes branches and the extra one between two nodes.
// Old node is one of the new ones, and one really new one is created.
// Tries more than one method for choosing a partition, uses best result.
RTREE_TEMPLATE
void RTREE_QUAL::SplitNode(Node* a_node, const Branch* a_branch, Node** a_newNode)
{
	RTREE_ASSERT(a_node);
	RTREE_ASSERT(a_branch);

	// Could just use local here, but member or external is faster since it is reused
	PartitionVars localVars;
	PartitionVars* parVars = &localVars;

	// Load all the branches into a buffer, initialize old node
	GetBranches(a_node, a_branch, parVars);

	// Find partition
	ChoosePartition(parVars, MINNODES);

	// Create a new node to hold (about) half of the branches
	*a_newNode = AllocNode();
	(*a_newNode)->m_level = a_node->m_level;

	// Put branches from buffer into 2 nodes according to the chosen partition
	a_node->m_count = 0;
	LoadNodes(a_node, *a_newNode, parVars);

	RTREE_ASSERT((a_node->m_count + (*a_newNode)->m_count) == parVars->m_total);
}


// Calculate the n-dimensional volume of a rectangle
RTREE_TEMPLATE
ELEMTYPEREAL RTREE_QUAL::RectVolume(Rect* a_rect)
{
	RTREE_ASSERT(a_rect);

	ELEMTYPEREAL volume = (ELEMTYPEREAL)1;

	for (int index = 0; index < NUMDIMS; ++index)
	{
		volume *= a_rect->m_max[index] - a_rect->m_min[index];
	}

	RTREE_ASSERT(volume >= (ELEMTYPEREAL)0);

	return volume;
}


// The exact volume of the bounding sphere for the given Rect
RTREE_TEMPLATE
ELEMTYPEREAL RTREE_QUAL::RectSphericalVolume(Rect* a_rect)
{
	RTREE_ASSERT(a_rect);

	ELEMTYPEREAL sumOfSquares = (ELEMTYPEREAL)0;
	ELEMTYPEREAL radius;

	for (int index = 0; index < NUMDIMS; ++index)
	{
		ELEMTYPEREAL halfExtent = ((ELEMTYPEREAL)a_rect->m_max[index] - (ELEMTYPEREAL)a_rect->m_min[index]) * (ELEMTYPEREAL)0.5;
		sumOfSquares += halfExtent * halfExtent;
	}

	radius = (ELEMTYPEREAL)sqrt(sumOfSquares);

	// Pow maybe slow, so test for common dims like 2,3 and just use x*x, x*x*x.
	if (NUMDIMS == 3)
	{
		return (radius * radius * radius * m_unitSphereVolume);
	}
	else if (NUMDIMS == 2)
	{
		return (radius * radius * m_unitSphereVolume);
	}
	else
	{
		return (ELEMTYPEREAL)(pow(radius, NUMDIMS) * m_unitSphereVolume);
	}
}


// Use one of the methods to calculate retangle volume
RTREE_TEMPLATE
ELEMTYPEREAL RTREE_QUAL::CalcRectVolume(Rect* a_rect)
{
#ifdef RTREE_USE_SPHERICAL_VOLUME
	return RectSphericalVolume(a_rect); // Slower but helps certain merge cases
#else // RTREE_USE_SPHERICAL_VOLUME
	return RectVolume(a_rect); // Faster but can cause poor merges
#endif // RTREE_USE_SPHERICAL_VOLUME
}


// Load branch buffer with branches from full node plus the extra branch.
RTREE_TEMPLATE
void RTREE_QUAL::GetBranches(Node* a_node, const Branch* a_branch, PartitionVars* a_parVars)
{
	RTREE_ASSERT(a_node);
	RTREE_ASSERT(a_branch);

	RTREE_ASSERT(a_node->m_count == MAXNODES);

	// Load the branch buffer
	for (int index = 0; index < MAXNODES; ++index)
	{
		a_parVars->m_branchBuf[index] = a_node->m_branch[index];
	}
	a_parVars->m_branchBuf[MAXNODES] = *a_branch;
	a_parVars->m_branchCount = MAXNODES + 1;

	// Calculate rect containing all in the set
	a_parVars->m_coverSplit = a_parVars->m_branchBuf[0].m_rect;
	for (int index = 1; index < MAXNODES + 1; ++index)
	{
		a_parVars->m_coverSplit = CombineRect(&a_parVars->m_coverSplit, &a_parVars->m_branchBuf[index].m_rect);
	}
	a_parVars->m_coverSplitArea = CalcRectVolume(&a_parVars->m_coverSplit);
}


// Method #0 for choosing a partition:
// As the seeds for the two groups, pick the two rects that would waste the
// most area if covered by a single rectangle, i.e. evidently the worst pair
// to have in the same group.
// Of the remaining, one at a time is chosen to be put in one of the two groups.
// The one chosen is the one with the greatest difference in area expansion
// depending on which group - the rect most strongly attracted to one group
// and repelled from the other.
// If one group gets too full (more would force other group to violate min
// fill requirement) then other group gets the rest.
// These last are the ones that can go in either group most easily.
RTREE_TEMPLATE
void RTREE_QUAL::ChoosePartition(PartitionVars* a_parVars, int a_minFill)
{
	RTREE_ASSERT(a_parVars);

	bool firstTime;
	ELEMTYPEREAL biggestDiff;
	int group, chosen = 0, betterGroup = 0;

	InitParVars(a_parVars, a_parVars->m_branchCount, a_minFill);
	PickSeeds(a_parVars);

	while (((a_parVars->m_count[0] + a_parVars->m_count[1]) < a_parVars->m_total)
		&& (a_parVars->m_count[0] < (a_parVars->m_total - a_parVars->m_minFill))
		&& (a_parVars->m_count[1] < (a_parVars->m_total - a_parVars->m_minFill)))
	{
		firstTime = true;
		for (int index = 0; index < a_parVars->m_total; ++index)
		{
			if (PartitionVars::NOT_TAKEN == a_parVars->m_partition[index])
			{
				Rect* curRect = &a_parVars->m_branchBuf[index].m_rect;
				Rect rect0 = CombineRect(curRect, &a_parVars->m_cover[0]);
				Rect rect1 = CombineRect(curRect, &a_parVars->m_cover[1]);
				ELEMTYPEREAL growth0 = CalcRectVolume(&rect0) - a_parVars->m_area[0];
				ELEMTYPEREAL growth1 = CalcRectVolume(&rect1) - a_parVars->m_area[1];
				ELEMTYPEREAL diff = growth1 - growth0;
				if (diff >= 0)
				{
					group = 0;
				}
				else
				{
					group = 1;
					diff = -diff;
				}

				if (firstTime || diff > biggestDiff)
				{
					firstTime = false;
					biggestDiff = diff;
					chosen = index;
					betterGroup = group;
				}
				else if ((diff == biggestDiff) && (a_parVars->m_count[group] < a_parVars->m_count[betterGroup]))
				{
					chosen = index;
					betterGroup = group;
				}
			}
		}
		RTREE_ASSERT(!firstTime);
		Classify(chosen, betterGroup, a_parVars);
	}

	// If one group too full, put remaining rects in the other
	if ((a_parVars->m_count[0] + a_parVars->m_count[1]) < a_parVars->m_total)
	{
		if (a_parVars->m_count[0] >= a_parVars->m_total - a_parVars->m_minFill)
		{
			group = 1;
		}
		else
		{
			group = 0;
		}
		for (int index = 0; index < a_parVars->m_total; ++index)
		{
			if (PartitionVars::NOT_TAKEN == a_parVars->m_partition[index])
			{
				Classify(index, group, a_parVars);
			}
		}
	}

	RTREE_ASSERT((a_parVars->m_count[0] + a_parVars->m_count[1]) == a_parVars->m_total);
	RTREE_ASSERT((a_parVars->m_count[0] >= a_parVars->m_minFill) &&
		(a_parVars->m_count[1] >= a_parVars->m_minFill));
}


// Copy branches from the buffer into two nodes according to the partition.
RTREE_TEMPLATE
void RTREE_QUAL::LoadNodes(Node* a_nodeA, Node* a_nodeB, PartitionVars* a_parVars)
{
	RTREE_ASSERT(a_nodeA);
	RTREE_ASSERT(a_nodeB);
	RTREE_ASSERT(a_parVars);

	for (int index = 0; index < a_parVars->m_total; ++index)
	{
		RTREE_ASSERT(a_parVars->m_partition[index] == 0 || a_parVars->m_partition[index] == 1);

		int targetNodeIndex = a_parVars->m_partition[index];
		Node* targetNodes[] = { a_nodeA, a_nodeB };

		// It is assured that AddBranch here will not cause a node split.
		bool nodeWasSplit = AddBranch(&a_parVars->m_branchBuf[index], targetNodes[targetNodeIndex], NULL);
		RTREE_ASSERT(!nodeWasSplit);
	}
}


// Initialize a PartitionVars structure.
RTREE_TEMPLATE
void RTREE_QUAL::InitParVars(PartitionVars* a_parVars, int a_maxRects, int a_minFill)
{
	RTREE_ASSERT(a_parVars);

	a_parVars->m_count[0] = a_parVars->m_count[1] = 0;
	a_parVars->m_area[0] = a_parVars->m_area[1] = (ELEMTYPEREAL)0;
	a_parVars->m_total = a_maxRects;
	a_parVars->m_minFill = a_minFill;
	for (int index = 0; index < a_maxRects; ++index)
	{
		a_parVars->m_partition[index] = PartitionVars::NOT_TAKEN;
	}
}


RTREE_TEMPLATE
void RTREE_QUAL::PickSeeds(PartitionVars* a_parVars)
{
	bool firstTime;
	int seed0 = 0, seed1 = 0;
	ELEMTYPEREAL worst, waste;
	ELEMTYPEREAL area[MAXNODES + 1];

	for (int index = 0; index < a_parVars->m_total; ++index)
	{
		area[index] = CalcRectVolume(&a_parVars->m_branchBuf[index].m_rect);
	}

	firstTime = true;
	for (int indexA = 0; indexA < a_parVars->m_total - 1; ++indexA)
	{
		for (int indexB = indexA + 1; indexB < a_parVars->m_total; ++indexB)
		{
			Rect oneRect = CombineRect(&a_parVars->m_branchBuf[indexA].m_rect, &a_parVars->m_branchBuf[indexB].m_rect);
			waste = CalcRectVolume(&oneRect) - area[indexA] - area[indexB];
			if (firstTime || waste > worst)
			{
				firstTime = false;
				worst = waste;
				seed0 = indexA;
				seed1 = indexB;
			}
		}
	}
	RTREE_ASSERT(!firstTime);

	Classify(seed0, 0, a_parVars);
	Classify(seed1, 1, a_parVars);
}


// Put a branch in one of the groups.
RTREE_TEMPLATE
void RTREE_QUAL::Classify(int a_index, int a_group, PartitionVars* a_parVars)
{
	RTREE_ASSERT(a_parVars);
	RTREE_ASSERT(PartitionVars::NOT_TAKEN == a_parVars->m_partition[a_index]);

	a_parVars->m_partition[a_index] = a_group;

	// Calculate combined rect
	if (a_parVars->m_count[a_group] == 0)
	{
		a_parVars->m_cover[a_group] = a_parVars->m_branchBuf[a_index].m_rect;
	}
	else
	{
		a_parVars->m_cover[a_group] = CombineRect(&a_parVars->m_branchBuf[a_index].m_rect, &a_parVars->m_cover[a_group]);
	}

	// Calculate volume of combined rect
	a_parVars->m_area[a_group] = CalcRectVolume(&a_parVars->m_cover[a_group]);

	++a_parVars->m_count[a_group];
}


// Delete a data rectangle from an index structure.
// Pass in a pointer to a Rect, the tid of the record, ptr to ptr to root node.
// Returns 1 if record not found, 0 if success.
// RemoveRect provides for eliminating the root.
RTREE_TEMPLATE
bool RTREE_QUAL::RemoveRect(Rect* a_rect, const DATATYPE& a_id, Node** a_root)
{
	RTREE_ASSERT(a_root);
	RTREE_ASSERT(*a_root);

	ListNode* reInsertList = NULL;

	if (!RemoveRectRec(a_rect, a_id, *a_root, &reInsertList))
	{
		// Found and deleted a data item
		// Reinsert any branches from eliminated nodes
		while (reInsertList)
		{
			Node* tempNode = reInsertList->m_node;

			for (int index = 0; index < tempNode->m_count; ++index)
			{
				// TODO go over this code. should I use (tempNode->m_level - 1)?
				InsertRect(tempNode->m_branch[index],
					a_root,
					tempNode->m_level);
			}

			ListNode* remLNode = reInsertList;
			reInsertList = reInsertList->m_next;

			FreeNode(remLNode->m_node);
			FreeListNode(remLNode);
		}

		// Check for redundant root (not leaf, 1 child) and eliminate TODO replace
		// if with while? In case there is a whole branch of redundant roots...
		if ((*a_root)->m_count == 1 && (*a_root)->IsInternalNode())
		{
			Node* tempNode = (*a_root)->m_branch[0].m_child;

			RTREE_ASSERT(tempNode);
			FreeNode(*a_root);
			*a_root = tempNode;
		}
		return false;
	}
	else
	{
		return true;
	}
}


// Delete a rectangle from non-root part of an index structure.
// Called by RemoveRect.  Descends tree recursively,
// merges branches on the way back up.
// Returns 1 if record not found, 0 if success.
RTREE_TEMPLATE
bool RTREE_QUAL::RemoveRectRec(Rect* a_rect, const DATATYPE& a_id, Node* a_node, ListNode** a_listNode)
{
	RTREE_ASSERT(a_node && a_listNode);
	RTREE_ASSERT(a_node->m_level >= 0);

	if (a_node->IsInternalNode())  // not a leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			if (a_rect == NULL || Overlap(a_rect, &(a_node->m_branch[index].m_rect)))
			{
				if (!RemoveRectRec(a_rect, a_id, a_node->m_branch[index].m_child, a_listNode))
				{
					if (a_node->m_branch[index].m_child->m_count >= MINNODES)
					{
						// child removed, just resize parent rect
						a_node->m_branch[index].m_rect = NodeCover(a_node->m_branch[index].m_child);
					}
					else
					{
						// child removed, not enough entries in node, eliminate node
						ReInsert(a_node->m_branch[index].m_child, a_listNode);
						DisconnectBranch(a_node, index); // Must return after this call as count has changed
					}
					return false;
				}
			}
		}
		return true;
	}
	else // A leaf node
	{
		for (int index = 0; index < a_node->m_count; ++index)
		{
			if (a_node->m_branch[index].m_data == a_id)
			{
				DisconnectBranch(a_node, index); // Must return after this call as count has changed
				return false;
			}
		}
		return true;
	}
}


// Decide whether two rectangles overlap.
RTREE_TEMPLATE
bool RTREE_QUAL::Overlap(Rect* a_rectA, Rect* a_rectB) const
{
	RTREE_ASSERT(a_rectA && a_rectB);

	for (int index = 0; index < NUMDIMS; ++index)
	{
		if (a_rectA->m_min[index] > a_rectB->m_max[index] ||
			a_rectB->m_min[index] > a_rectA->m_max[index])
		{
			return false;
		}
	}
	return true;
}

// Decide whether two rectangles overlap.
RTREE_TEMPLATE
ELEMTYPE RTREE_QUAL::SquareDistance(Rect const& a_rectA, Rect const& a_rectB) const
{
	ELEMTYPE dist{};

	for (int index = 0; index < NUMDIMS; ++index)
	{
		auto diff1 = a_rectA.m_min[index] - a_rectB.m_max[index];
		auto diff2 = a_rectA.m_max[index] - a_rectB.m_min[index];

		dist += diff1 * diff2 < 0 ? 0 : std::min(diff1 * diff1, diff2 * diff2);

	}
	return dist;
}

// Add a node to the reinsertion list.  All its branches will later
// be reinserted into the index structure.
RTREE_TEMPLATE
void RTREE_QUAL::ReInsert(Node* a_node, ListNode** a_listNode)
{
	ListNode* newListNode;

	newListNode = AllocListNode();
	newListNode->m_node = a_node;
	newListNode->m_next = *a_listNode;
	*a_listNode = newListNode;
}


// Search in an index tree or subtree for all data retangles that overlap the argument rectangle.
RTREE_TEMPLATE
bool RTREE_QUAL::Search(Node* a_node, Rect* a_rect, int& a_foundCount, std::function<bool(const DATATYPE&)> callback) const
{
	RTREE_ASSERT(a_node);
	RTREE_ASSERT(a_node->m_level >= 0);
	RTREE_ASSERT(a_rect);

	if (a_node->IsInternalNode())
	{
		// This is an internal node in the tree
		for (int index = 0; index < a_node->m_count; ++index)
		{
			if (Overlap(a_rect, &a_node->m_branch[index].m_rect))
			{
				if (!Search(a_node->m_branch[index].m_child, a_rect, a_foundCount, callback))
				{
					// The callback indicated to stop searching
					return false;
				}
			}
		}
	}
	else
	{
		// This is a leaf node
		for (int index = 0; index < a_node->m_count; ++index)
		{
			if (Overlap(a_rect, &a_node->m_branch[index].m_rect))
			{
				DATATYPE& id = a_node->m_branch[index].m_data;
				++a_foundCount;

				if (callback && !callback(id))
				{
					return false; // Don't continue searching
				}
			}
		}
	}

	return true; // Continue searching
}


RTREE_TEMPLATE
std::vector<typename RTREE_QUAL::Rect> RTREE_QUAL::ListTree() const
{
	RTREE_ASSERT(m_root);
	RTREE_ASSERT(m_root->m_level >= 0);

	std::vector<Rect> treeList;

	std::vector<Node*> toVisit;
	toVisit.push_back(m_root);

	while (!toVisit.empty()) {
		Node* a_node = toVisit.back();
		toVisit.pop_back();
		if (a_node->IsInternalNode())
		{
			// This is an internal node in the tree
			for (int index = 0; index < a_node->m_count; ++index)
			{
				treeList.push_back(a_node->m_branch[index].m_rect);
				toVisit.push_back(a_node->m_branch[index].m_child);
			}
		}
		else
		{
			// This is a leaf node
			for (int index = 0; index < a_node->m_count; ++index)
			{
				treeList.push_back(a_node->m_branch[index].m_rect);
			}
		}
	}

	return treeList;
}


#undef RTREE_TEMPLATE
#undef RTREE_QUAL

template<class CoordType = float>
struct RectTemplate {
	RectTemplate() {}

	RectTemplate(CoordType a_minX, CoordType a_minY, CoordType a_maxX, CoordType a_maxY) {
		min[0] = a_minX;
		min[1] = a_minY;

		max[0] = a_maxX;
		max[1] = a_maxY;
		if (a_minX > a_maxX)
		{
			min[0] = a_maxX;
			max[0] = a_minX;
		}
		if (a_minY > a_maxY)
		{
			min[1] = a_maxY;
			max[1] = a_minY;
		}
	}

	bool operator==(const RectTemplate &o) const {
		return min[0] == o.min[0] && min[1] == o.min[1] && max[0] == o.max[0] &&
			max[1] == o.max[1];
	}

	CoordType min[2];
	CoordType max[2];
};

#pragma pop_macro("min")
#pragma pop_macro("max")

#endif //RTREE_H