/********************************************************************** * * GEOS - Geometry Engine Open Source * http://geos.osgeo.org * * Copyright (C) 2005-2006 Refractions Research Inc. * Copyright (C) 2001-2002 Vivid Solutions Inc. * * This is free software; you can redistribute and/or modify it under * the terms of the GNU Lesser General Public Licence as published * by the Free Software Foundation. * See the COPYING file for more information. * ********************************************************************** * * Last port: geomgraph/Label.java r428 (JTS-1.12+) * **********************************************************************/ #ifndef GEOS_GEOMGRAPH_LABEL_H #define GEOS_GEOMGRAPH_LABEL_H #include #include #include #include #include // for operator<< namespace geos { namespace geomgraph { // geos.geomgraph /** \brief * A Label indicates the topological relationship of a component * of a topology graph to a given Geometry. * * This class supports labels for relationships to two Geometrys, * which is sufficient for algorithms for binary operations. * * Topology graphs support the concept of labeling nodes and edges in the graph. * The label of a node or edge specifies its topological relationship to one or * more geometries. (In fact, since JTS operations have only two arguments labels * are required for only two geometries). A label for a node or edge has one or * two elements, depending on whether the node or edge occurs in one or both of the * input Geometrys. Elements contain attributes which categorize the * topological location of the node or edge relative to the parent * Geometry; that is, whether the node or edge is in the interior, * boundary or exterior of the Geometry. Attributes have a value * from the set {Interior, Boundary, Exterior}. In a node each * element has a single attribute <On>. For an edge each element has a * triplet of attributes <Left, On, Right>. * * It is up to the client code to associate the 0 and 1 TopologyLocations * with specific geometries. * */ class GEOS_DLL Label { public: friend std::ostream& operator<< (std::ostream&, const Label&); /** \brief * Converts a Label to a Line label * (that is, one with no side Locations) * */ static Label toLineLabel(const Label& label); /** \brief * Construct a Label with a single location for both Geometries. */ Label(geom::Location onLoc); /** \brief * Construct a Label with the location specified * for the given Geometry. * * Other geometry location will be set to * Location::NONE. */ Label(uint32_t geomIndex, geom::Location onLoc); /** \brief * Construct a Label with On, Left and Right locations for both Geometries. * * Initialize the locations for both Geometries to the given values. */ Label(geom::Location onLoc, geom::Location leftLoc, geom::Location rightLoc); /// Copy ctor Label(const Label& l); Label& operator= (const Label& l); /** \brief * Initialize both locations to Location::NONE * * isNull() should return true after this kind of construction */ Label(); /** \brief * Construct a Label with On, Left and Right locations for the * given Geometries. * Initialize the locations for the other Geometry to * Location::NONE */ Label(uint32_t geomIndex, geom::Location onLoc, geom::Location leftLoc, geom::Location rightLoc); void flip(); geom::Location getLocation(uint32_t geomIndex, uint32_t posIndex) const; geom::Location getLocation(uint32_t geomIndex) const; void setLocation(uint32_t geomIndex, uint32_t posIndex, geom::Location location); void setLocation(uint32_t geomIndex, geom::Location location); void setAllLocations(uint32_t geomIndex, geom::Location location); void setAllLocationsIfNull(uint32_t geomIndex, geom::Location location); void setAllLocationsIfNull(geom::Location location); /** \brief * Merge this label with another one. * * Merging updates any null attributes of this label with the attributes * from lbl */ void merge(const Label& lbl); int getGeometryCount() const; bool isNull() const; bool isNull(uint32_t geomIndex) const; bool isAnyNull(uint32_t geomIndex) const; bool isArea() const; bool isArea(uint32_t geomIndex) const; bool isLine(uint32_t geomIndex) const; bool isEqualOnSide(const Label& lbl, uint32_t side) const; bool allPositionsEqual(uint32_t geomIndex, geom::Location loc) const; /** \brief * Converts one GeometryLocation to a Line location */ void toLine(uint32_t geomIndex); std::string toString() const; private: TopologyLocation elt[2]; }; std::ostream& operator<< (std::ostream&, const Label&); } // namespace geos.geomgraph } // namespace geos #ifdef GEOS_INLINE # include "geos/geomgraph/Label.inl" #endif #endif // ifndef GEOS_GEOMGRAPH_LABEL_H