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/********************************************************************* |
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* * |
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* Copyright (c) 1997,1998, 1999 * |
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* Multimedia DB Group and DEIS - CSITE-CNR, * |
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* University of Bologna, Bologna, ITALY. * |
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* * |
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* All Rights Reserved. * |
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* * |
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* Permission to use, copy, and distribute this software and its * |
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* documentation for NON-COMMERCIAL purposes and without fee is * |
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* hereby granted provided that this copyright notice appears in * |
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* all copies. * |
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* * |
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* THE AUTHORS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE * |
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* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING * |
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* BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, * |
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* FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR * |
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* SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A * |
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* RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * |
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* DERIVATIVES. * |
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* * |
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*********************************************************************/ |
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#ifndef MTNODE_H |
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#define MTNODE_H |
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#include "MTentry.h" |
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class MTquery; |
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class MTnode : public GiSTnode { |
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// long wasted_space[100]; // only for debug purposes |
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public: |
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// constructors, destructors, etc. |
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MTnode(): GiSTnode(), obj(NULL) { }; |
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MTnode(const MTnode& node): GiSTnode(node), obj(node.obj) { }; |
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GiSTobjid IsA() const { return MTNODE_CLASS; } |
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GiSTobject *Copy() const { return new MTnode(*this); } |
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GiSTobject *NCopy(); // copy the node invalidating its entries (useful in Split) |
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void Print(ostream& os) const; |
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// search methods |
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GiSTpage SearchMinPenalty(const GiSTentry& entry) const; // overload of virtual method |
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GiSTlist<MTentry *> RangeSearch(const MTquery& query); // range search optimized for distance computations |
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// insertion and deletion |
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void InsertBefore(const GiSTentry& entry, int index); // overload of virtual method in order to insert the entry in the right place |
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// two of the basic GiST methods |
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GiSTnode *PickSplit(); |
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GiSTentry* Union() const; |
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// support functions for methods above |
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MTnode *PromotePart(); // object promotion |
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MTnode *PromoteVote(); // object confirmed promotion |
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int *PickCandidates(); // pick a sample of children objects |
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void Split(MTnode *node, int *leftvec, int *rightvec, int *leftdeletes, int *rightdeletes); // perform the split between the parents |
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// used (in split and) in deletion |
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int IsUnderFull(const GiSTstore &store) const; |
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// required support methods |
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GiSTentry *CreateEntry() const { return new MTentry; } |
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int FixedLength() const { return sizeofEntry(); } |
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void InvalidateEntry(BOOL isNew); // invalidate the distance from its parent |
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void InvalidateEntries(); // invalidate the distance of its children |
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void Order(); // order the children with respect to the distance from their parent |
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void mMRadius(MTentry *e) const; // compute the min & MAX radii for this node storing them in e |
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MTentry *Entry() const; // retrieve the entry representing this node |
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double distance(int i) const; // useful to avoid computation of known distances |
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Object *obj; // object copied from the node's entry, useful for Union() |
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}; |
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#endif |
