diff options
author | Stanislaw Halik <sthalik@misaki.pl> | 2023-02-25 01:29:23 +0100 |
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committer | Stanislaw Halik <sthalik@misaki.pl> | 2023-02-25 01:29:23 +0100 |
commit | f07a72f805f4b761b7610366fd60f131d3fab4c5 (patch) | |
tree | bc75cbbd331d72055927775f5fc4407771ccfd26 /src/RTree.hpp | |
parent | 14035691511638051b7a51fd0dce0541b956b6d3 (diff) |
a
Diffstat (limited to 'src/RTree.hpp')
-rw-r--r-- | src/RTree.hpp | 1438 |
1 files changed, 1438 insertions, 0 deletions
diff --git a/src/RTree.hpp b/src/RTree.hpp new file mode 100644 index 00000000..7b94bc2f --- /dev/null +++ b/src/RTree.hpp @@ -0,0 +1,1438 @@ +#pragma once +#include "Rtree.h" +#include <math.h> +#include <stdlib.h> +#include <cassert> +#include <algorithm> + +#ifdef RTREE_STDIO +// 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 = nullptr; + } + + ~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 = nullptr; + } + } + + template< typename TYPE > + size_t Write(const TYPE& a_value) + { + 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) + { + ASSERT(m_file); + return fwrite(const_cast<void*>((const void*)a_array), sizeof(TYPE) * a_count, 1, m_file); + } + + template< typename TYPE > + size_t Read(TYPE& a_value) + { + 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) + { + ASSERT(m_file); + return fread((void*)a_array, sizeof(TYPE) * a_count, 1, m_file); + } +}; +#endif + + +RTREE_TEMPLATE +RTREE_QUAL::RTree() +{ + ASSERT(MAXNODES > MINNODES); + 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; + m_unitSphereVolume = (ELEMTYPEREAL)UNIT_SPHERE_VOLUMES[NUMDIMS]; +} + + +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) + { + ASSERT(a_min[index] <= a_max[index]); + } +#endif //_DEBUG + + Branch branch; + branch.m_data = a_dataId; + branch.m_child = nullptr; + + 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 ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], const DATATYPE& a_dataId) +{ +#ifdef _DEBUG + for(int index=0; index<NUMDIMS; ++index) + { + 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 +template<typename F> +int RTREE_QUAL::Search(const ELEMTYPE a_min[NUMDIMS], const ELEMTYPE a_max[NUMDIMS], F&& callback) const +{ +#ifdef _DEBUG + for(int index=0; index<NUMDIMS; ++index) + { + 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 +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; + } +} + + +#ifdef RTREE_STDIO +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 +} + +#endif + +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 = ¤t->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 = ¤t->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; + } + } +} + +#ifdef RTREE_STDIO +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 +} +#endif + + +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) +{ + ASSERT(a_node); + 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) +{ + 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) +{ + ASSERT(a_node && a_newNode); + 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 + 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) +{ + ASSERT(a_root); + ASSERT(a_level >= 0 && a_level <= (*a_root)->m_level); +#ifdef _DEBUG + for(int index=0; index < NUMDIMS; ++index) + { + 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, nullptr); + + // add the split node as a child of the new root + branch.m_rect = NodeCover(newNode); + branch.m_child = newNode; + AddBranch(&branch, newRoot, nullptr); + + // 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) +{ + 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) +{ + ASSERT(a_branch); + 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 + { + 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) +{ + ASSERT(a_node && (a_index >= 0) && (a_index < MAXNODES)); + 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) +{ + ASSERT(a_rect && a_node); + + bool firstTime = true; + ELEMTYPEREAL increase; + ELEMTYPEREAL bestIncr = (ELEMTYPEREAL)-1; + ELEMTYPEREAL area; + ELEMTYPEREAL bestArea; + 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) +{ + ASSERT(a_rectA && a_rectB); + + Rect newRect; + + for(int index = 0; index < NUMDIMS; ++index) + { + newRect.m_min[index] = Min(a_rectA->m_min[index], a_rectB->m_min[index]); + newRect.m_max[index] = 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) +{ + ASSERT(a_node); + 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); + + 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) +{ + 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]; + } + + 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) +{ + 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) +{ + ASSERT(a_node); + ASSERT(a_branch); + + 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) +{ + ASSERT(a_parVars); + + 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))) + { + biggestDiff = (ELEMTYPEREAL) -1; + 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(diff > biggestDiff) + { + biggestDiff = diff; + chosen = index; + betterGroup = group; + } + else if((diff == biggestDiff) && (a_parVars->m_count[group] < a_parVars->m_count[betterGroup])) + { + chosen = index; + betterGroup = group; + } + } + } + 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); + } + } + } + + ASSERT((a_parVars->m_count[0] + a_parVars->m_count[1]) == a_parVars->m_total); + 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) +{ + ASSERT(a_nodeA); + ASSERT(a_nodeB); + ASSERT(a_parVars); + + for(int index=0; index < a_parVars->m_total; ++index) + { + 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], nullptr); + ASSERT(!nodeWasSplit); + } +} + + +// Initialize a PartitionVars structure. +RTREE_TEMPLATE +void RTREE_QUAL::InitParVars(PartitionVars* a_parVars, int a_maxRects, int a_minFill) +{ + 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) +{ + 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); + } + + worst = -a_parVars->m_coverSplitArea - 1; + 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(waste > worst) + { + worst = waste; + seed0 = indexA; + seed1 = indexB; + } + } + } + + 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) +{ + ASSERT(a_parVars); + 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) +{ + ASSERT(a_rect && a_root); + ASSERT(*a_root); + + ListNode* reInsertList = nullptr; + + 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; + + 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) +{ + ASSERT(a_rect && a_node && a_listNode); + 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(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 +{ + 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; +} + + +// 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 +template<typename F> +bool RTREE_QUAL::Search(Node* a_node, Rect* a_rect, int& a_foundCount, F&& callback) const +{ + ASSERT(a_node); + ASSERT(a_node->m_level >= 0); + 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 +{ + ASSERT(m_root); + 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; +} + +RTREE_TEMPLATE +void RTree<DATATYPE, ELEMTYPE, NUMDIMS, ELEMTYPEREAL, TMAXNODES, TMINNODES>::GetFirst(RTree::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; + } +} + +RTREE_TEMPLATE +RTREE_QUAL::Iterator::StackElement& RTREE_QUAL::Iterator::Pop() +{ + ASSERT(m_tos > 0); + --m_tos; + return m_stack[m_tos]; +} + +RTREE_TEMPLATE +void RTREE_QUAL::Iterator::Push(RTree::Node* a_node, int a_branchIndex) +{ + m_stack[m_tos].m_node = a_node; + m_stack[m_tos].m_branchIndex = a_branchIndex; + ++m_tos; + ASSERT(m_tos <= MAX_STACK); +} + +RTREE_TEMPLATE +void RTREE_QUAL::Iterator::GetBounds(ELEMTYPE* a_min, ELEMTYPE* a_max) +{ + 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]; + } +} + +RTREE_TEMPLATE +const DATATYPE& RTREE_QUAL::Iterator::operator*() const +{ + ASSERT(IsNotNull()); + StackElement& curTos = m_stack[m_tos - 1]; + return curTos.m_node->m_branch[curTos.m_branchIndex].m_data; +} + +RTREE_TEMPLATE +DATATYPE& RTREE_QUAL::Iterator::operator*() +{ + ASSERT(IsNotNull()); + StackElement& curTos = m_stack[m_tos - 1]; + return curTos.m_node->m_branch[curTos.m_branchIndex].m_data; +} + +RTREE_TEMPLATE +bool RTREE_QUAL::Iterator::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; + } + } + } +} |