Basic implementation of Geometry, constructed and destructed by GeometryFactory. More...

#include <geos.h>

Inheritance diagram for geos::geom::Geometry:

Public Types
using	ConstVect = std::vector< const Geometry * >
	A vector of const Geometry pointers.

using	NonConstVect = std::vector< Geometry * >
	A vector of non-const Geometry pointers.

using	Ptr = std::unique_ptr< Geometry >
	An unique_ptr of Geometry.

Public Member Functions
std::unique_ptr< Geometry >	clone () const
	Make a deep-copy of this Geometry.

virtual	~Geometry ()
	Destroy Geometry and all components.

const GeometryFactory *	getFactory () const
	Gets the factory which contains the context in which this geometry was created. More...

void	setUserData (void *newUserData)
	A simple scheme for applications to add their own custom data to a Geometry. An example use might be to add an object representing a Coordinate Reference System. More...

void *	getUserData () const
	Gets the user data object for this geometry, if any. More...

int	getSRID () const
	Returns the ID of the Spatial Reference System used by the Geometry. More...

virtual void	setSRID (int newSRID)
	Sets the ID of the Spatial Reference System used by the Geometry.

const PrecisionModel *	getPrecisionModel () const
	Get the PrecisionModel used to create this Geometry.

virtual const CoordinateXY *	getCoordinate () const =0
	Returns a vertex of this Geometry, or NULL if this is the empty geometry.

virtual std::unique_ptr< CoordinateSequence >	getCoordinates () const =0
	Returns this Geometry vertices. Caller takes ownership of the returned object.

virtual std::size_t	getNumPoints () const =0
	Returns the count of this Geometrys vertices.

virtual bool	isSimple () const
	Returns false if the Geometry not simple.

virtual std::string	getGeometryType () const =0
	Return a string representation of this Geometry type.

virtual bool	hasCurvedComponents () const
	Returns whether the Geometry contains curved components.

virtual GeometryTypeId	getGeometryTypeId () const =0
	Return an integer representation of this Geometry type.

virtual std::size_t	getNumGeometries () const
	Returns the number of geometries in this collection, or 1 if this is not a collection. More...

virtual const Geometry *	getGeometryN (std::size_t) const
	Returns a pointer to the nth Geometry in this collection (or self if this is not a collection)

bool	isValid () const
	Tests the validity of this `Geometry`. More...

virtual bool	isEmpty () const =0
	Returns whether or not the set of points in this Geometry is empty.

virtual bool	isRectangle () const
	Polygon overrides to check for actual rectangle.

virtual Dimension::DimensionType	getDimension () const =0
	Returns the dimension of this Geometry (0=point, 1=line, 2=surface)

virtual bool	hasDimension (Dimension::DimensionType d) const
	Checks whether any component of this geometry has dimension d.

virtual bool	isDimensionStrict (Dimension::DimensionType d) const
	Checks whether this Geometry consists only of components having dimension d.

bool	isPuntal () const

bool	isLineal () const

bool	isPolygonal () const

bool	isMixedDimension () const

bool	isMixedDimension (Dimension::DimensionType *baseDim) const

bool	isCollection () const

virtual uint8_t	getCoordinateDimension () const =0
	Returns the coordinate dimension of this Geometry (2=XY, 3=XYZ or XYM, 4=XYZM).

virtual bool	hasZ () const =0

virtual bool	hasM () const =0

virtual std::unique_ptr< Geometry >	getBoundary () const =0
	Returns the boundary, or an empty geometry of appropriate dimension if this `Geometry` is empty. More...

virtual int	getBoundaryDimension () const =0
	Returns the dimension of this Geometrys inherent boundary.

virtual std::unique_ptr< Geometry >	getEnvelope () const
	Returns this Geometrys bounding box.

virtual const Envelope *	getEnvelopeInternal () const =0
	Returns the minimum and maximum x and y values in this Geometry, or a null Envelope if this Geometry is empty.

virtual bool	disjoint (const Geometry *other) const

virtual bool	touches (const Geometry *other) const
	Returns true if the DE-9IM intersection matrix for the two Geometrys is FT*****, FT*** or FT***.

virtual bool	intersects (const Geometry *g) const
	Returns true if disjoint returns false.

virtual bool	crosses (const Geometry *g) const

virtual bool	within (const Geometry *g) const
	Returns true if the DE-9IM intersection matrix for the two Geometrys is TFF**.

virtual bool	contains (const Geometry *g) const
	Returns true if other.within(this) returns true.

virtual bool	overlaps (const Geometry *g) const
	Returns true if the DE-9IM intersection matrix for the two Geometrys is TTT (for two points or two surfaces) 1TT (for two curves).

bool	relate (const Geometry *g, const std::string &intersectionPattern) const
	Returns true if the elements in the DE-9IM intersection matrix for the two Geometrys match the elements in intersectionPattern. More...

bool	relate (const Geometry &g, const std::string &intersectionPattern) const

std::unique_ptr< IntersectionMatrix >	relate (const Geometry *g) const
	Returns the DE-9IM intersection matrix for the two Geometrys.

std::unique_ptr< IntersectionMatrix >	relate (const Geometry &g) const

bool	equals (const Geometry *g) const
	Returns true if the DE-9IM intersection matrix for the two Geometrys is TFFFF.

bool	covers (const Geometry *g) const
	Returns `true` if this geometry covers the specified geometry. More...

bool	coveredBy (const Geometry *g) const
	Tests whether this geometry is covered by the specified geometry. More...

virtual std::string	toString () const
	Returns the Well-known Text representation of this Geometry.

virtual std::string	toText () const

std::unique_ptr< Geometry >	buffer (double distance) const

std::unique_ptr< Geometry >	buffer (double distance, int quadrantSegments) const
	Returns a buffer region around this Geometry having the given width and with a specified number of segments used to approximate curves. More...

std::unique_ptr< Geometry >	buffer (double distance, int quadrantSegments, int endCapStyle) const
	Computes a buffer area around this geometry having the given width and with a specified accuracy of approximation for circular arcs, and using a specified end cap style. More...

virtual std::unique_ptr< Geometry >	convexHull () const
	Returns the smallest convex Polygon that contains all the points in the Geometry.

std::unique_ptr< Geometry >	reverse () const
	Computes a new geometry which has all component coordinate sequences in reverse order (opposite orientation) to this one. More...

std::unique_ptr< Geometry >	intersection (const Geometry *other) const
	Returns a Geometry representing the points shared by this Geometry and other. More...

std::unique_ptr< Geometry >	Union (const Geometry *other) const
	Returns a Geometry representing all the points in this Geometry and other. More...

Ptr	Union () const
	Computes the union of all the elements of this geometry. Heterogeneous GeometryCollections are fully supported. More...

std::unique_ptr< Geometry >	difference (const Geometry *other) const
	Returns a Geometry representing the points making up this Geometry that do not make up other. More...

std::unique_ptr< Geometry >	symDifference (const Geometry *other) const
	Returns a set combining the points in this Geometry not in other, and the points in other not in this Geometry. More...

virtual bool	equalsExact (const Geometry *other, double tolerance=0) const =0
	Returns true iff the two Geometrys are of the same type and their vertices corresponding by index are equal up to a specified distance tolerance. Geometries are not required to have the same dimemsion; any Z/M values are ignored.

virtual bool	equalsIdentical (const Geometry *other) const =0
	Returns true if the two geometries are of the same type and their vertices corresponding by index are equal in all dimensions.

virtual void	apply_rw (const CoordinateFilter *filter)=0

virtual void	apply_ro (CoordinateFilter *filter) const =0

virtual void	apply_rw (GeometryFilter *filter)

virtual void	apply_ro (GeometryFilter *filter) const

virtual void	apply_rw (GeometryComponentFilter *filter)

virtual void	apply_ro (GeometryComponentFilter *filter) const

virtual void	apply_rw (CoordinateSequenceFilter &filter)=0

virtual void	apply_ro (CoordinateSequenceFilter &filter) const =0

template<class T >
void	applyComponentFilter (T &f) const
	Apply a filter to each component of this geometry. The filter is expected to provide a .filter(const Geometry*) method. More...

virtual void	normalize ()=0

int	compareTo (const Geometry *geom) const
	Comparator for sorting geometry.

virtual double	getArea () const
	Returns the area of this Geometry.

virtual double	getLength () const
	Returns the length of this Geometry.

virtual double	distance (const Geometry *g) const

virtual bool	isWithinDistance (const Geometry *geom, double cDistance) const
	Tests whether the distance from this Geometry to another is less than or equal to a specified value. More...

virtual std::unique_ptr< Point >	getCentroid () const
	Computes the centroid of this `Geometry`. More...

virtual bool	getCentroid (CoordinateXY &ret) const
	Computes the centroid of this Geometry as a Coordinate. More...

std::unique_ptr< Point >	getInteriorPoint () const
	Computes an interior point of this `Geometry`. More...

void	geometryChanged ()
	Notifies this Geometry that its Coordinates have been changed by an external party (using a CoordinateFilter, for example).

virtual void	geometryChangedAction ()=0
	Notifies this Geometry that its Coordinates have been changed by an external party.

Static Public Member Functions
static GeometryTypeId	multiTypeId (GeometryTypeId typeId)

Protected Member Functions
virtual Geometry *	cloneImpl () const =0
	Make a deep-copy of this Geometry.

virtual Geometry *	reverseImpl () const =0
	Make a geometry with coordinates in reverse order.

virtual bool	isEquivalentClass (const Geometry *other) const
	Returns whether the two Geometrys are equal, from the point of view of the equalsExact method.

virtual int	compareToSameClass (const Geometry *geom) const =0

bool	equal (const CoordinateXY &a, const CoordinateXY &b, double tolerance) const

	Geometry (const Geometry &geom)

	Geometry (const GeometryFactory *factory)
	Construct a geometry with the given GeometryFactory. More...

virtual int	getSortIndex () const =0

Static Protected Member Functions
template<typename T >
static bool	hasNonEmptyElements (const std::vector< T > *geometries)
	Returns true if the array contains any non-empty Geometrys.

static bool	hasNullElements (const CoordinateSequence *list)
	Returns true if the CoordinateSequence contains any null elements.

template<typename T >
static bool	hasNullElements (const std::vector< T > *geometries)
	Returns true if the vector contains any null elements.

static void	checkNotGeometryCollection (const Geometry *g)

template<typename T >
static int	compare (const T &a, const T &b)

template<typename T >
static std::vector< std::unique_ptr< Geometry > >	toGeometryArray (std::vector< std::unique_ptr< T >> &&v)

static std::vector< std::unique_ptr< Geometry > >	toGeometryArray (std::vector< std::unique_ptr< Geometry >> &&v)

Protected Attributes
int	SRID

Friends
class	GeometryFactory

Detailed Description

Basic implementation of Geometry, constructed and destructed by GeometryFactory.

clone returns a deep copy of the object. Use GeometryFactory to construct.

Binary Predicates

Because it is not clear at this time what semantics for spatial analysis methods involving GeometryCollections would be useful, GeometryCollections are not supported as arguments to binary predicates (other than convexHull) or the relate method.

Set-Theoretic Methods

The spatial analysis methods will return the most specific class possible to represent the result. If the result is homogeneous, a Point, LineString, or Polygon will be returned if the result contains a single element; otherwise, a MultiPoint, MultiLineString, or MultiPolygon will be returned. If the result is heterogeneous a GeometryCollection will be returned.

Because it is not clear at this time what semantics for set-theoretic methods involving GeometryCollections would be useful, GeometryCollections are not supported as arguments to the set-theoretic methods.

Representation of Computed Geometries

The SFS states that the result of a set-theoretic method is the "point-set" result of the usual set-theoretic definition of the operation (SFS 3.2.21.1). However, there are sometimes many ways of representing a point set as a Geometry.

The SFS does not specify an unambiguous representation of a given point set returned from a spatial analysis method. One goal of JTS is to make this specification precise and unambiguous. JTS will use a canonical form for Geometrys returned from spatial analysis methods. The canonical form is a Geometry which is simple and noded:

Simple means that the Geometry returned will be simple according to the JTS definition of isSimple.
Noded applies only to overlays involving LineStrings. It means that all intersection points on LineStrings will be present as endpoints of LineStrings in the result.

This definition implies that non-simple geometries which are arguments to spatial analysis methods must be subjected to a line-dissolve process to ensure that the results are simple.

Constructed Points And The Precision Model

The results computed by the set-theoretic methods may contain constructed points which are not present in the input Geometry. These new points arise from intersections between line segments in the edges of the input Geometry. In the general case it is not possible to represent constructed points exactly. This is due to the fact that the coordinates of an intersection point may contain twice as many bits of precision as the coordinates of the input line segments. In order to represent these constructed points explicitly, JTS must truncate them to fit the PrecisionModel.

Unfortunately, truncating coordinates moves them slightly. Line segments which would not be coincident in the exact result may become coincident in the truncated representation. This in turn leads to "topology collapses" – situations where a computed element has a lower dimension than it would in the exact result.

When JTS detects topology collapses during the computation of spatial analysis methods, it will throw an exception. If possible the exception will report the location of the collapse.

equals(Object) and hashCode are not overridden, so that when two topologically equal Geometries are added to HashMaps and HashSets, they remain distinct. This behaviour is desired in many cases.

Constructor & Destructor Documentation

◆ Geometry()

geos::geom::Geometry::Geometry ( const GeometryFactory * factory )

protected

Construct a geometry with the given GeometryFactory.

Will keep a reference to the factory, so don't delete it until al Geometry objects referring to it are deleted.

Parameters

factory

Member Function Documentation

◆ apply_ro()

virtual void geos::geom::Geometry::apply_ro ( CoordinateSequenceFilter & filter ) const

pure virtual

Performs a read-only operation on the coordinates in this Geometry's CoordinateSequences.

Parameters

filter the filter to apply

Implemented in geos::geom::Surface, geos::geom::Point, and geos::geom::GeometryCollection.

◆ apply_rw()

virtual void geos::geom::Geometry::apply_rw ( CoordinateSequenceFilter & filter )

pure virtual

Performs an operation on the coordinates in this Geometry's CoordinateSequences. If the filter reports that a coordinate value has been changed, geometryChanged will be called automatically.

Parameters

filter the filter to apply

Implemented in geos::geom::Surface, geos::geom::Point, and geos::geom::GeometryCollection.

◆ applyComponentFilter()

template<class T >

void geos::geom::Geometry::applyComponentFilter ( T & f ) const

inline

Apply a filter to each component of this geometry. The filter is expected to provide a .filter(const Geometry*) method.

I intend similar templated methods to replace all the virtual apply_rw and apply_ro functions... –strk(2005-02-06);

Referenced by geos::operation::linemerge::LineSequencer::add().

◆ buffer() [1/3]

std::unique_ptr<Geometry> geos::geom::Geometry::buffer ( double distance ) const

Returns a buffer region around this Geometry having the given width.

Exceptions

util::TopologyException if a robustness error occurs

◆ buffer() [2/3]

std::unique_ptr<Geometry> geos::geom::Geometry::buffer	(	double	distance,
		int	quadrantSegments
	)		const

Returns a buffer region around this Geometry having the given width and with a specified number of segments used to approximate curves.

Exceptions

util::TopologyException if a robustness error occurs

◆ buffer() [3/3]

std::unique_ptr<Geometry> geos::geom::Geometry::buffer	(	double	distance,
		int	quadrantSegments,
		int	endCapStyle
	)		const

Computes a buffer area around this geometry having the given width and with a specified accuracy of approximation for circular arcs, and using a specified end cap style.

Buffer area boundaries can contain circular arcs. To represent these arcs using linear geometry they must be approximated with line segments.

The quadrantSegments argument allows controlling the accuracy of the approximation by specifying the number of line segments used to represent a quadrant of a circle

The end cap style specifies the buffer geometry that will be created at the ends of linestrings. The styles provided are:

BufferOp::CAP_ROUND - (default) a semi-circle
BufferOp::CAP_BUTT - a straight line perpendicular to the end segment
BufferOp::CAP_SQUARE - a half-square

Parameters

distance	the width of the buffer (may be positive, negative or 0)
quadrantSegments	the number of line segments used to represent a quadrant of a circle
endCapStyle	the end cap style to use

Returns: an area geometry representing the buffer region

Exceptions

util::TopologyException if a robustness error occurs

See also: BufferOp

◆ coveredBy()

bool geos::geom::Geometry::coveredBy ( const Geometry * g ) const

Tests whether this geometry is covered by the specified geometry.

The coveredBy predicate has the following equivalent definitions:

Every point of this geometry is a point of the other geometry.
The DE-9IM Intersection Matrix for the two geometries matches [T*F**F***] or [*TF**F***] or [**FT*F***] or [**F*TF***]
g.covers(this) (coveredBy is the converse of covers)

If either geometry is empty, the value of this predicate is false.

This predicate is similar to within, but is more inclusive (i.e. returns true for more cases).

Parameters

g	the `Geometry` with which to compare this `Geometry`

Returns: true if this Geometry is covered by g

See also: Geometry::within; Geometry::covers

◆ covers()

bool geos::geom::Geometry::covers ( const Geometry * g ) const

Returns true if this geometry covers the specified geometry.

The covers predicate has the following equivalent definitions:

Every point of the other geometry is a point of this geometry.
The DE-9IM Intersection Matrix for the two geometries is T*****FF* or T****FF or ***T**FF* or ****T*FF*
g.coveredBy(this) (covers is the inverse of coveredBy)

If either geometry is empty, the value of this predicate is false.

This predicate is similar to contains, but is more inclusive (i.e. returns true for more cases). In particular, unlike contains it does not distinguish between points in the boundary and in the interior of geometries. For most situations, covers should be used in preference to contains. As an added benefit, covers is more amenable to optimization, and hence should be more performant.

Parameters

g	the `Geometry` with which to compare this `Geometry`

Returns: true if this Geometry covers g

See also: Geometry::contains; Geometry::coveredBy

◆ crosses()

virtual bool geos::geom::Geometry::crosses ( const Geometry * g ) const

virtual

Tests whether this geometry crosses the specified geometry.

The crosses predicate has the following equivalent definitions:

The geometries have some but not all interior points in common.
The DE-9IM Intersection Matrix for the two geometries matches
- [T*T******] (for P/L, P/A, and L/A situations)
- [T*****T**] (for L/P, A/P, and A/L situations)
- [0********] (for L/L situations) For any other combination of dimensions this predicate returns false.

The SFS defined this predicate only for P/L, P/A, L/L, and L/A situations. JTS extends the definition to apply to L/P, A/P and A/L situations as well, in order to make the relation symmetric.

Parameters

g	the `Geometry` with which to compare this `Geometry`

Returns: true if the two Geometrys cross.

◆ difference()

std::unique_ptr<Geometry> geos::geom::Geometry::difference ( const Geometry * other ) const

Returns a Geometry representing the points making up this Geometry that do not make up other.

Exceptions

util::TopologyException	if a robustness error occurs
util::IllegalArgumentException	if either input is a non-empty GeometryCollection

◆ disjoint()

virtual bool geos::geom::Geometry::disjoint ( const Geometry * other ) const

virtual

Tests whether this geometry is disjoint from the specified geometry.

The disjoint predicate has the following equivalent definitions:

The two geometries have no point in common
The DE-9IM Intersection Matrix for the two geometries matches [FF*FF****]
! g.intersects(this) (disjoint is the inverse of intersects)

Parameters

other the Geometry with which to compare this Geometry

Returns: true if the two Geometrys are disjoint

See also: Geometry::intersects

◆ distance()

virtual double geos::geom::Geometry::distance ( const Geometry * g ) const

virtual

Returns the minimum distance between this Geometry and the Geometry g

Parameters

g	the Geometry to calculate distance to

Returns: the distance in cartesian units

◆ getBoundary()

virtual std::unique_ptr<Geometry> geos::geom::Geometry::getBoundary ( ) const

pure virtual

Returns the boundary, or an empty geometry of appropriate dimension if this Geometry is empty.

(In the case of zero-dimensional geometries, an empty GeometryCollection is returned.) For a discussion of this function, see the OpenGIS Simple Features Specification. As stated in SFS Section 2.1.13.1, "the boundary of a Geometry is a set of Geometries of the next lower dimension."

Returns: the closure of the combinatorial boundary of this Geometry. Ownershipof the returned object transferred to caller.

Implemented in geos::geom::Polygon, geos::geom::Point, geos::geom::MultiPolygon, geos::geom::MultiPoint, geos::geom::MultiLineString, and geos::geom::GeometryCollection.

◆ getCentroid() [1/2]

virtual std::unique_ptr<Point> geos::geom::Geometry::getCentroid ( ) const

virtual

Computes the centroid of this Geometry.

The centroid is equal to the centroid of the set of component Geometries of highest dimension (since the lower-dimension geometries contribute zero "weight" to the centroid)

Returns: a Point which is the centroid of this Geometry

◆ getCentroid() [2/2]

virtual bool geos::geom::Geometry::getCentroid ( CoordinateXY & ret ) const

virtual

Computes the centroid of this Geometry as a Coordinate.

Returns false if centroid cannot be computed (EMPTY geometry)

◆ getFactory()

const GeometryFactory* geos::geom::Geometry::getFactory ( ) const

inline

Gets the factory which contains the context in which this geometry was created.

Returns: the factory for this geometry

◆ getInteriorPoint()

std::unique_ptr<Point> geos::geom::Geometry::getInteriorPoint ( ) const

Computes an interior point of this Geometry.

An interior point is guaranteed to lie in the interior of the Geometry, if it possible to calculate such a point exactly. Otherwise, the point may lie on the boundary of the geometry.

Returns: a Point which is in the interior of this Geometry, or null if the geometry doesn't have an interior (empty)

◆ getNumGeometries()

virtual std::size_t geos::geom::Geometry::getNumGeometries ( ) const

inlinevirtual

Returns the number of geometries in this collection, or 1 if this is not a collection.

Empty collection or multi-geometry types return 0, and empty simple geometry types return 1.

Reimplemented in geos::geom::GeometryCollection.

◆ getSRID()

int geos::geom::Geometry::getSRID ( ) const

inline

Returns the ID of the Spatial Reference System used by the Geometry.

GEOS supports Spatial Reference System information in the simple way defined in the SFS. A Spatial Reference System ID (SRID) is present in each Geometry object. Geometry provides basic accessor operations for this field, but no others. The SRID is represented as an integer.

Returns: the ID of the coordinate space in which the Geometry is defined.

◆ getUserData()

void* geos::geom::Geometry::getUserData ( ) const

inline

Gets the user data object for this geometry, if any.

Returns: the user data object, or null if none set

◆ intersection()

std::unique_ptr<Geometry> geos::geom::Geometry::intersection ( const Geometry * other ) const

Returns a Geometry representing the points shared by this Geometry and other.

Exceptions

util::TopologyException	if a robustness error occurs
util::IllegalArgumentException	if either input is a non-empty GeometryCollection

◆ isValid()

bool geos::geom::Geometry::isValid ( ) const

Tests the validity of this Geometry.

Subclasses provide their own definition of "valid".

Returns: true if this Geometry is valid

See also: IsValidOp

◆ isWithinDistance()

virtual bool geos::geom::Geometry::isWithinDistance	(	const Geometry *	geom,
		double	cDistance
	)		const

virtual

Tests whether the distance from this Geometry to another is less than or equal to a specified value.

Parameters

geom	the Geometry to check the distance to
cDistance	the distance value to compare

Returns: true if the geometries are less than distance apart.

Todo:: doesn't seem to need being virtual, make it concrete

◆ normalize()

virtual void geos::geom::Geometry::normalize ( )

pure virtual

Reorganizes this Geometry into normal form (or canonical form). Starting point of rings is lower left, collections are ordered by geometry type, etc.

Implemented in geos::geom::Point, geos::geom::Polygon, and geos::geom::GeometryCollection.

◆ relate()

bool geos::geom::Geometry::relate	(	const Geometry *	g,
		const std::string &	intersectionPattern
	)		const

Returns true if the elements in the DE-9IM intersection matrix for the two Geometrys match the elements in intersectionPattern.

IntersectionPattern elements may be: 0 1 2 T ( = 0, 1 or 2) F ( = -1) * ( = -1, 0, 1 or 2).

For more information on the DE-9IM, see the OpenGIS Simple Features Specification.

Exceptions

util::IllegalArgumentException if either arg is a collection

◆ reverse()

std::unique_ptr<Geometry> geos::geom::Geometry::reverse ( ) const

inline

Computes a new geometry which has all component coordinate sequences in reverse order (opposite orientation) to this one.

Returns: a reversed geometry

◆ setUserData()

void geos::geom::Geometry::setUserData ( void * newUserData )

inline

A simple scheme for applications to add their own custom data to a Geometry. An example use might be to add an object representing a Coordinate Reference System.

Note that user data objects are not present in geometries created by construction methods.

Parameters

newUserData an object, the semantics for which are defined by the application using this Geometry

◆ symDifference()

std::unique_ptr<Geometry> geos::geom::Geometry::symDifference ( const Geometry * other ) const

Returns a set combining the points in this Geometry not in other, and the points in other not in this Geometry.

Exceptions

util::TopologyException	if a robustness error occurs
util::IllegalArgumentException	if either input is a non-empty GeometryCollection

◆ Union() [1/2]

Ptr geos::geom::Geometry::Union ( ) const

Computes the union of all the elements of this geometry. Heterogeneous GeometryCollections are fully supported.

The result obeys the following contract:

Unioning a set of LineStrings has the effect of fully noding and dissolving the linework.
Unioning a set of Polygons will always return a polygonal geometry (unlike Geometry::Union(const Geometry* other) const), which may return geometries of lower dimension if a topology collapse occurred.

Returns: the union geometry

See also: UnaryUnionOp

◆ Union() [2/2]

std::unique_ptr<Geometry> geos::geom::Geometry::Union ( const Geometry * other ) const

Returns a Geometry representing all the points in this Geometry and other.

Exceptions

util::TopologyException	if a robustness error occurs
util::IllegalArgumentException	if either input is a non-empty GeometryCollection

The documentation for this class was generated from the following file:

Geometry.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Friends

Detailed Description

Binary Predicates

Set-Theoretic Methods

Representation of Computed Geometries

Constructed Points And The Precision Model

Constructor & Destructor Documentation

◆ Geometry()

Member Function Documentation

◆ apply_ro()

◆ apply_rw()

◆ applyComponentFilter()

◆ buffer() [1/3]

◆ buffer() [2/3]

◆ buffer() [3/3]

◆ coveredBy()

◆ covers()

◆ crosses()

◆ difference()

◆ disjoint()

◆ distance()

◆ getBoundary()

◆ getCentroid() [1/2]

◆ getCentroid() [2/2]

◆ getFactory()

◆ getInteriorPoint()

◆ getNumGeometries()

◆ getSRID()

◆ getUserData()

◆ intersection()

◆ isValid()

◆ isWithinDistance()

◆ normalize()

◆ relate()

◆ reverse()

◆ setUserData()

◆ symDifference()

◆ Union() [1/2]

◆ Union() [2/2]