/********************************************************************** * * GEOS - Geometry Engine Open Source * http://geos.osgeo.org * * Copyright (c) 2024 Martin Davis * Copyright (C) 2024 Paul Ramsey * * 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. * **********************************************************************/ #pragma once #include #include #include // for operator<< // Forward declarations namespace geos { namespace geom { class Envelope; } } using geos::geom::Envelope; using geos::geom::Location; namespace geos { // geos. namespace operation { // geos.operation namespace relateng { // geos.operation.relateng class GEOS_DLL TopologyPredicate { public: /* Virtual destructor to ensure proper cleanup of derived classes */ virtual ~TopologyPredicate() {}; /** * Gets the name of the predicate. * * @return the predicate name */ virtual std::string name() const = 0; /** * Indicates that the value of the predicate can be finalized * based on its current state. */ virtual void finish() = 0; /** * Tests if the predicate value is known. * * @return true if the result is known */ virtual bool isKnown() const = 0; /** * Gets the current value of the predicate result. * The value is only valid if isKnown() is true. * * @return the predicate result value */ virtual bool value() const = 0; /** * Reports whether this predicate requires self-noding for * geometries which contain crossing edges * (for example, LineString, or GeometryCollection * containing lines or polygons which may self-intersect). * Self-noding ensures that intersections are computed consistently * in cases which contain self-crossings and mutual crossings. * * Most predicates require this, but it can * be avoided for simple intersection detection * (such as in RelatePredicate#intersects() * and RelatePredicate#disjoint(). * Avoiding self-noding improves performance for polygonal inputs. * * @return true if self-noding is required. */ virtual bool requireSelfNoding() const { return true; }; /** * Reports whether this predicate requires interaction between * the input geometries. * This is the case if * * IM[I, I] >= 0 or IM[I, B] >= 0 or IM[B, I] >= 0 or IM[B, B] >= 0 * * This allows a fast result if * the envelopes of the geometries are disjoint. * * @return true if the geometries must interact */ virtual bool requireInteraction() const { return true; }; /** * Reports whether this predicate requires that the source * cover the target. * This is the case if * * IM[Ext(Src), Int(Tgt)] = F and IM[Ext(Src), Bdy(Tgt)] = F * * If true, this allows a fast result if * the source envelope does not cover the target envelope. * * @param isSourceA indicates the source input geometry * @return true if the predicate requires checking whether the source covers the target */ virtual bool requireCovers(bool isSourceA) { (void)isSourceA; return false; } /** * Reports whether this predicate requires checking if the source input intersects * the Exterior of the target input. * This is the case if: * * IM[Int(Src), Ext(Tgt)] >= 0 or IM[Bdy(Src), Ext(Tgt)] >= 0 * * If false, this may permit a faster result in some geometric situations. * * @param isSourceA indicates the source input geometry * @return true if the predicate requires checking whether the source intersects the target exterior */ virtual bool requireExteriorCheck(bool isSourceA) const { (void)isSourceA; return true; } /** * Initializes the predicate for a specific geometric case. * This may allow the predicate result to become known * if it can be inferred from the dimensions. * * @param dimA the dimension of geometry A * @param dimB the dimension of geometry B * * @see Dimension */ virtual void init(int dimA, int dimB) { (void)dimA; (void)dimB; }; /** * Initializes the predicate for a specific geometric case. * This may allow the predicate result to become known * if it can be inferred from the envelopes. * * @param envA the envelope of geometry A * @param envB the envelope of geometry B */ virtual void init(const Envelope& envA, const Envelope& envB) { //-- default if envelopes provide no information (void)envA; (void)envB; }; /** * Updates the entry in the DE-9IM intersection matrix * for given Location in the input geometries. * * If this method is called with a {@link Dimension} value * which is less than the current value for the matrix entry, * the implementing class should avoid changing the entry * if this would cause information loss. * * @param locA the location on the A axis of the matrix * @param locB the location on the B axis of the matrix * @param dimension the dimension value for the entry * * @see Dimension * @see Location */ virtual void updateDimension(Location locA, Location locB, int dimension) = 0; friend std::ostream& operator<<(std::ostream& os, const TopologyPredicate& ns) { os << ns.name(); return os; } }; } // namespace geos.operation.relateng } // namespace geos.operation } // namespace geos