/********************************************************************* * * * Copyright (c) 1997,1998, 1999 * * Multimedia DB Group and DEIS - CSITE-CNR, * * University of Bologna, Bologna, ITALY. * * * * All Rights Reserved. * * * * Permission to use, copy, and distribute this software and its * * documentation for NON-COMMERCIAL purposes and without fee is * * hereby granted provided that this copyright notice appears in * * all copies. * * * * THE AUTHORS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE * * SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING * * BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, * * FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR * * SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A * * RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * * DERIVATIVES. * * * *********************************************************************/ #ifndef MTENTRY_H #define MTENTRY_H #include #include #include #ifndef MAXDOUBLE #define MAXDOUBLE DBL_MAX #endif #include "GiST.h" #include "MTobject.h" class MTentry; // MTkey is a covering region indicated by an object and its covering radii: obj, rmin, rmax // We also throw in some standard geo operators to support various query predicates, etc. class MTkey: public GiSTobject { public: Object obj; // object private: double rmin, rmax; // covering radii public: friend MTentry; // constructors, destructors, assignment, etc. MTkey(): rmin(0), rmax(MAXDOUBLE), distance(-maxDist()), splitted(FALSE), recomp(FALSE) { } MTkey(const MTkey& k): obj(k.obj), rmin(k.rmin), rmax(k.rmax), distance(k.distance), splitted(k.splitted), recomp(k.recomp) { } MTkey(Object& p_obj, const double p_rmin, const double p_rmax, const double p_distance=-maxDist(), const BOOL p_splitted=FALSE, const BOOL p_recomp=FALSE): obj(p_obj), rmin(p_rmin), rmax(p_rmax), distance(p_distance), splitted(p_splitted), recomp(p_recomp) { } GiSTobject *Copy() const { return new MTkey(*this); } ~MTkey() { } GiSTobjid IsA() { return MTKEY_CLASS; } MTkey& operator = (const MTkey& k) { obj=k.obj; rmin=k.rmin; rmax=k.rmax; distance=k.distance; splitted=k.splitted; recomp=k.recomp; return *this; } // covering region property and comparison methods int operator==(const MTkey& k) { return ((!recomp)&&(!k.recomp)&&(obj==k.obj)&&(rmin==k.rmin)&&(rmax==k.rmax)&&(distance==k.distance)); } int overlap (const MTkey& k) { double d=obj.distance(k.obj); return ((d+rmax>=k.rmin)&&(d+k.rmax>=rmin)&&(d=k.rmin)&&(d+rmax<=k.rmax)); } int contains(const MTkey& k) { double d=obj.distance(k.obj); return ((d-k.rmax>=rmin)&&(d+k.rmax<=rmax)); } double area() { return obj.area(rmax); } // expand this covering region to contain k MTkey *expand(const MTkey& k) { MTkey *result; double d=obj.distance(k.obj); result=new MTkey(obj, MIN(rmin, d), MAX(rmax, d)); return result; } Object object() const { return obj; } double minradius() const { return rmin; } double maxradius() const { return rmax; } double distance; // Here we store the distance between the entry and its parent, only for index performance, in order to minimize the number of distance computations; BOOL splitted; // indicate that the node has been splitted BOOL recomp; // indicate that the node has been splitted but that no Union has been performed (thus radii are in a potentially inconsistent state): this can happen after a split // I/O methods #ifdef PRINTING_OBJECTS void Print(ostream& os) const { os << '"'; os << "(" << obj << ", " << rmin << ", " << rmax << ")" << '"'; } #endif }; #ifdef PRINTING_OBJECTS inline ostream& operator<< (ostream& os, const MTkey& k) { k.Print(os); return os; } #endif class MTpenalty: public GiSTpenalty { // we have to create a sub-class in order to add the member value distance public: MTpenalty(): GiSTpenalty(), distance(-maxDist()) { } MTpenalty(const double v, const double d): GiSTpenalty(v), distance(d) { } double distance; // this is necessary since each penalty is defined by two values: the radius increase and the distance from the entry }; int sizeofEntry(); class MTentry: public GiSTentry { // this are the entries stored in each node public: // constructors, destructors, etc. MTentry() { } MTentry(const MTkey& k, const GiSTpage p) { key=new MTkey(k); ptr=p; } MTentry(const MTentry& e): GiSTentry(e) { key=new MTkey(*(MTkey *)(e.key)); } GiSTobjid IsA() const { return MTENTRY_CLASS; } GiSTobject *Copy() const { return new MTentry(*this); } void InitKey() { key=new MTkey; } int IsEqual(const GiSTobject& obj) const { if(obj.IsA()!=MTENTRY_CLASS) return 0; return ((*((MTkey *)key)==(*((MTkey *)(((const MTentry&) obj).key))))); } // cast key member to class MTkey *. Prevents compiler warnings. MTkey *Key() const { return (MTkey *)key; } // basic GiST methods GiSTpenalty *Penalty(const GiSTentry &newEntry) const; GiSTpenalty *Penalty(const GiSTentry &newEntry, MTpenalty *minPenalty) const; // redefined in order to optimize distance computations // Other methods we're required to supply int CompressedLength() const { return object().CompressedLength()+3*sizeof(double)+2*sizeof(BOOL); // compressedEntry is: Object, rmin, rmax, distance, splitted, recomp } GiSTcompressedEntry Compress() const; void Decompress(const GiSTcompressedEntry entry); // Method for ordered domains int Compare(const GiSTentry& entry) const { assert(entry.IsA()==MTENTRY_CLASS); double d=Key()->distance-((MTentry &)entry).Key()->distance; int i=0; if(d>0) i=1; else if(d<0) i=-1; return i; } // I/O methods #ifdef PRINTING_OBJECTS void Print(ostream& os) const { key->Print(os); os << "->" << Ptr() << " (" << Key()->distance << ")"; if(Key()->splitted) os << " *"; if(Key()->recomp) os << " #"; os << endl; } #endif // access to private members const MTkey& cregion() const { return *Key(); } Object& object() const { return Key()->obj; } double minradius() const { return Key()->rmin; } double maxradius() const { return Key()->rmax; } void setobject(const Object& o) { Key()->obj=o; } void setminradius(double d) { Key()->rmin=d; } void setmaxradius(double d) { Key()->rmax=d; } }; #endif