libgeos-dev 3.2.2-3ubuntu1 / usr / include / geos / geom / prep / PreparedGeometry.h

/**********************************************************************
 * $Id: PreparedGeometry.h 2418 2009-04-29 08:15:21Z strk $
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.refractions.net
 *
 * Copyright (C) 2006 Refractions Research 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: geom/prep/PreparedGeometry.java rev. 1.11 (JTS-1.10)
 *
 **********************************************************************/

#ifndef GEOS_GEOM_PREP_PREPAREDGEOMETRY_H
#define GEOS_GEOM_PREP_PREPAREDGEOMETRY_H


// Forward declarations
namespace geos {
	namespace geom { 
		class Geometry;
	}
}


namespace geos {
namespace geom { // geos::geom
namespace prep { // geos::geom::prep

/**
 * \class PreparedGeometry
 *
 * \brief
 * An interface for classes which prepare {@link Geometry}s 
 * in order to optimize the performance
 * of repeated calls to specific geometric operations.
 * 
 * A given implementation may provide optimized implementations
 * for only some of the specified methods, 
 * and delegate the remaining methods to the original {@link Geometry} operations.
 * An implementation may also only optimize certain situations,
 * and delegate others. 
 * See the implementing classes for documentation about which methods and situations
 * they optimize.
 * 
 */
class PreparedGeometry {
public:
	virtual ~PreparedGeometry() {};
	
	/**
	 * Gets the original {@link Geometry} which has been prepared.
	 * 
	 * @return the base geometry
	 */
	virtual const geom::Geometry & getGeometry() const =0;

	/**
	 * Tests whether the base {@link Geometry} contains a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry contains the given Geometry
	 * 
	 * @see Geometry#contains(Geometry)
	 */
	virtual bool contains(const geom::Geometry *geom) const =0;

	/** \brief
	 * Tests whether the base {@link Geometry} properly contains
	 * a given geometry.
	 * 
	 * The <code>containsProperly</code> predicate has the following
	 * equivalent definitions:
	 * 
	 * - Every point of the other geometry is a point of this
	 *   geometry's interior.
	 * - The DE-9IM Intersection Matrix for the two geometries matches 
	 *   <code>[T**FF*FF*]</code>
	 *
         * In other words, if the test geometry has any interaction with
	 * the boundary of the target
         * geometry the result of <tt>containsProperly</tt> is <tt>false</tt>.
         * This is different semantics to the {@link Geometry::contains}
	 * predicate, * in which test geometries can intersect the target's
	 * boundary and still be contained.
	 * 
         * The advantage of using this predicate is that it can be computed
         * efficiently, since it avoids the need to compute the full
	 * topological relationship of the input boundaries in cases where
	 * they intersect.
	 *
         * An example use case is computing the intersections
         * of a set of geometries with a large polygonal geometry.
         * Since <tt>intersection</tt> is a fairly slow operation, it can
	 * be more efficient
         * to use <tt>containsProperly</tt> to filter out test geometries
	 * which lie
         * wholly inside the area.  In these cases the intersection is
         * known <i>a priori</i> to be exactly the original test geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry properly contains the given Geometry
	 *
	 * @see Geometry::contains
	 * 
	 */
	virtual bool containsProperly(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} is covered by a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry is covered by the given Geometry
	 * 
	 * @see Geometry#coveredBy(Geometry)
	 */
	virtual bool coveredBy(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} covers a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry covers the given Geometry
	 * 
	 * @see Geometry#covers(Geometry)
	 */
	virtual bool covers(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} crosses a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry crosses the given Geometry
	 * 
	 * @see Geometry#crosses(Geometry)
	 */
	virtual bool crosses(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} is disjoint from a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry is disjoint from the given Geometry
	 * 
	 * @see Geometry#disjoint(Geometry)
	 */
	virtual bool disjoint(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} intersects a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry intersects the given Geometry
	 * 
	 * @see Geometry#intersects(Geometry)
	 */
	virtual bool intersects(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} overlaps a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry overlaps the given Geometry
	 * 
	 * @see Geometry#overlaps(Geometry)
	 */
	virtual bool overlaps(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} touches a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry touches the given Geometry
	 * 
	 * @see Geometry#touches(Geometry)
	 */
	virtual bool touches(const geom::Geometry *geom) const =0;

	/**
	 * Tests whether the base {@link Geometry} is within a given geometry.
	 * 
	 * @param geom the Geometry to test
	 * @return true if this Geometry is within the given Geometry
	 * 
	 * @see Geometry#within(Geometry)
	 */
	virtual bool within(const geom::Geometry *geom) const =0;
};


} // namespace geos::geom::prep
} // namespace geos::geom
} // namespace geos


#endif // ndef GEOS_GEOM_PREP_PREPAREDGEOMETRY_H

/**********************************************************************
 * $Log$
 **********************************************************************/