Abstract curve base class for OGRLineString, OGRCircularString and OGRCompoundCurve. More...

#include <ogr_geometry.h>

Inheritance diagram for OGRCurve:

Public Types
typedef OGRPoint	ChildType
	Type of child elements. More...

Public Member Functions
ConstIterator	begin () const
	Return begin of a point iterator. More...

ConstIterator	end () const
	Return end of a point iterator. More...

virtual double	get_Length () const =0
	Returns the length of the curve. More...

virtual void	StartPoint (OGRPoint *) const =0
	Return the curve start point. More...

virtual void	EndPoint (OGRPoint *) const =0
	Return the curve end point. More...

virtual int	get_IsClosed () const
	Return TRUE if curve is closed. More...

virtual void	Value (double, OGRPoint *) const =0
	Fetch point at given distance along curve. More...

virtual OGRLineString *	CurveToLine (double dfMaxAngleStepSizeDegrees=0, const char const papszOptions=nullptr) const =0
	Return a linestring from a curve geometry. More...

virtual int	getDimension () const override
	Get the dimension of this object. More...

virtual int	getNumPoints () const =0
	Return the number of points of a curve geometry. More...

virtual OGRPointIterator *	getPointIterator () const =0
	Returns a point iterator over the curve. More...

virtual OGRBoolean	IsConvex () const
	Returns if a (closed) curve forms a convex shape. More...

virtual double	get_Area () const =0
	Get the area of the (closed) curve. More...

OGRSimpleCurve *	toSimpleCurve ()
	Down-cast to OGRSimpleCurve*. More...

const OGRSimpleCurve *	toSimpleCurve () const
	Down-cast to OGRSimpleCurve*. More...

Public Member Functions inherited from OGRGeometry
	OGRGeometry (const OGRGeometry &other)
	Copy constructor. More...

OGRGeometry &	operator= (const OGRGeometry &other)
	Assignment operator. More...

bool	operator== (const OGRGeometry &other) const
	Returns if two geometries are equal. More...

bool	operator!= (const OGRGeometry &other) const
	Returns if two geometries are different. More...

virtual int	getCoordinateDimension () const
	Get the dimension of the coordinates in this object. More...

int	CoordinateDimension () const
	Get the dimension of the coordinates in this object. More...

virtual OGRBoolean	IsEmpty () const =0
	Returns TRUE (non-zero) if the object has no points. More...

virtual OGRBoolean	IsValid () const
	Test if the geometry is valid. More...

virtual OGRBoolean	IsSimple () const
	Test if the geometry is simple. More...

OGRBoolean	Is3D () const

OGRBoolean	IsMeasured () const

virtual OGRBoolean	IsRing () const
	Test if the geometry is a ring. More...

virtual void	empty ()=0
	Clear geometry information. More...

virtual OGRGeometry *	clone () const CPL_WARN_UNUSED_RESULT=0
	Make a copy of this object. More...

virtual void	getEnvelope (OGREnvelope *psEnvelope) const =0
	Computes and returns the bounding envelope for this geometry in the passed psEnvelope structure. More...

virtual void	getEnvelope (OGREnvelope3D *psEnvelope) const =0
	Computes and returns the bounding envelope (3D) for this geometry in the passed psEnvelope structure. More...

virtual int	WkbSize () const =0
	Returns size of related binary representation. More...

OGRErr	importFromWkb (const GByte *, int=-1, OGRwkbVariant=wkbVariantOldOgc)
	Assign geometry from well known binary data. More...

virtual OGRErr	importFromWkb (const unsigned char *, int, OGRwkbVariant, int &nBytesConsumedOut)=0
	Assign geometry from well known binary data. More...

virtual OGRErr	exportToWkb (OGRwkbByteOrder, unsigned char *, OGRwkbVariant=wkbVariantOldOgc) const =0
	Convert a geometry into well known binary format. More...

virtual OGRErr	importFromWkt (const char **ppszInput)=0
	Assign geometry from well known text data. More...

OGRErr	importFromWkt (char ppszInput) CPL_WARN_DEPRECATED("Use importFromWkt( const char) instead")
	Deprecated. More...

virtual OGRErr	exportToWkt (char **ppszDstText, OGRwkbVariant=wkbVariantOldOgc) const =0
	Convert a geometry into well known text format. More...

virtual OGRwkbGeometryType	getGeometryType () const =0
	Fetch geometry type. More...

OGRwkbGeometryType	getIsoGeometryType () const
	Get the geometry type that conforms with ISO SQL/MM Part3. More...

virtual const char *	getGeometryName () const =0
	Fetch WKT name for geometry type. More...

virtual void	dumpReadable (FILE , const char =nullptr, char **papszOptions=nullptr) const
	Dump geometry in well known text format to indicated output file. More...

virtual void	flattenTo2D ()=0
	Convert geometry to strictly 2D. More...

virtual char *	exportToGML (const char const papszOptions=nullptr) const
	Convert a geometry into GML format. More...

virtual char *	exportToKML () const
	Convert a geometry into KML format. More...

virtual char *	exportToJson () const
	Convert a geometry into GeoJSON format. More...

virtual void	accept (IOGRGeometryVisitor *visitor)=0
	Accept a visitor. More...

virtual void	accept (IOGRConstGeometryVisitor *visitor) const =0
	Accept a visitor. More...

virtual GEOSGeom	exportToGEOS (GEOSContextHandle_t hGEOSCtxt) const CPL_WARN_UNUSED_RESULT
	Returns a GEOSGeom object corresponding to the geometry. More...

virtual OGRBoolean	hasCurveGeometry (int bLookForNonLinear=FALSE) const
	Returns if this geometry is or has curve geometry. More...

virtual OGRGeometry *	getCurveGeometry (const char const papszOptions=nullptr) const CPL_WARN_UNUSED_RESULT
	Return curve version of this geometry. More...

virtual OGRGeometry *	getLinearGeometry (double dfMaxAngleStepSizeDegrees=0, const char const papszOptions=nullptr) const CPL_WARN_UNUSED_RESULT
	Return, possibly approximate, non-curve version of this geometry. More...

virtual void	closeRings ()
	Force rings to be closed. More...

virtual void	setCoordinateDimension (int nDimension)
	Set the coordinate dimension. More...

virtual void	set3D (OGRBoolean bIs3D)
	Add or remove the Z coordinate dimension. More...

virtual void	setMeasured (OGRBoolean bIsMeasured)
	Add or remove the M coordinate dimension. More...

virtual void	assignSpatialReference (OGRSpatialReference *poSR)
	Assign spatial reference to this object. More...

OGRSpatialReference *	getSpatialReference (void) const
	Returns spatial reference system for object. More...

virtual OGRErr	transform (OGRCoordinateTransformation *poCT)=0
	Apply arbitrary coordinate transformation to geometry. More...

OGRErr	transformTo (OGRSpatialReference *poSR)
	Transform geometry to new spatial reference system. More...

virtual void	segmentize (double dfMaxLength)
	Modify the geometry such it has no segment longer then the given distance. More...

virtual OGRBoolean	Intersects (const OGRGeometry *) const
	Do these features intersect? More...

virtual OGRBoolean	Equals (const OGRGeometry *) const =0
	Returns TRUE if two geometries are equivalent. More...

virtual OGRBoolean	Disjoint (const OGRGeometry *) const
	Test for disjointness. More...

virtual OGRBoolean	Touches (const OGRGeometry *) const
	Test for touching. More...

virtual OGRBoolean	Crosses (const OGRGeometry *) const
	Test for crossing. More...

virtual OGRBoolean	Within (const OGRGeometry *) const
	Test for containment. More...

virtual OGRBoolean	Contains (const OGRGeometry *) const
	Test for containment. More...

virtual OGRBoolean	Overlaps (const OGRGeometry *) const
	Test for overlap. More...

virtual OGRGeometry *	Boundary () const CPL_WARN_UNUSED_RESULT
	Compute boundary. More...

virtual double	Distance (const OGRGeometry *) const
	Compute distance between two geometries. More...

virtual OGRGeometry *	ConvexHull () const CPL_WARN_UNUSED_RESULT
	Compute convex hull. More...

virtual OGRGeometry *	Buffer (double dfDist, int nQuadSegs=30) const CPL_WARN_UNUSED_RESULT
	Compute buffer of geometry. More...

virtual OGRGeometry *	Intersection (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
	Compute intersection. More...

virtual OGRGeometry *	Union (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
	Compute union. More...

virtual OGRGeometry *	UnionCascaded () const CPL_WARN_UNUSED_RESULT
	Compute union using cascading. More...

virtual OGRGeometry *	Difference (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
	Compute difference. More...

virtual OGRGeometry *	SymDifference (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
	Compute symmetric difference. More...

virtual OGRErr	Centroid (OGRPoint *poPoint) const
	Compute the geometry centroid. More...

virtual OGRGeometry *	Simplify (double dTolerance) const CPL_WARN_UNUSED_RESULT
	Simplify the geometry. More...

OGRGeometry *	SimplifyPreserveTopology (double dTolerance) const CPL_WARN_UNUSED_RESULT
	Simplify the geometry while preserving topology. More...

virtual OGRGeometry *	DelaunayTriangulation (double dfTolerance, int bOnlyEdges) const CPL_WARN_UNUSED_RESULT
	Return a Delaunay triangulation of the vertices of the geometry. More...

virtual OGRGeometry *	Polygonize () const CPL_WARN_UNUSED_RESULT
	Polygonizes a set of sparse edges. More...

virtual double	Distance3D (const OGRGeometry *poOtherGeom) const
	Returns the 3D distance between two geometries. More...

virtual void	swapXY ()
	Swap x and y coordinates. More...

OGRPoint *	toPoint ()
	Down-cast to OGRPoint*. More...

const OGRPoint *	toPoint () const
	Down-cast to OGRPoint*. More...

OGRCurve *	toCurve ()
	Down-cast to OGRCurve*. More...

const OGRCurve *	toCurve () const
	Down-cast to OGRCurve*. More...

OGRSimpleCurve *	toSimpleCurve ()
	Down-cast to OGRSimpleCurve*. More...

const OGRSimpleCurve *	toSimpleCurve () const
	Down-cast to OGRSimpleCurve*. More...

OGRLineString *	toLineString ()
	Down-cast to OGRLineString*. More...

const OGRLineString *	toLineString () const
	Down-cast to OGRLineString*. More...

OGRLinearRing *	toLinearRing ()
	Down-cast to OGRLinearRing*. More...

const OGRLinearRing *	toLinearRing () const
	Down-cast to OGRLinearRing*. More...

OGRCircularString *	toCircularString ()
	Down-cast to OGRCircularString*. More...

const OGRCircularString *	toCircularString () const
	Down-cast to OGRCircularString*. More...

OGRCompoundCurve *	toCompoundCurve ()
	Down-cast to OGRCompoundCurve*. More...

const OGRCompoundCurve *	toCompoundCurve () const
	Down-cast to OGRCompoundCurve*. More...

OGRSurface *	toSurface ()
	Down-cast to OGRSurface*. More...

const OGRSurface *	toSurface () const
	Down-cast to OGRSurface*. More...

OGRPolygon *	toPolygon ()
	Down-cast to OGRPolygon*. More...

const OGRPolygon *	toPolygon () const
	Down-cast to OGRPolygon*. More...

OGRTriangle *	toTriangle ()
	Down-cast to OGRTriangle*. More...

const OGRTriangle *	toTriangle () const
	Down-cast to OGRTriangle*. More...

OGRCurvePolygon *	toCurvePolygon ()
	Down-cast to OGRCurvePolygon*. More...

const OGRCurvePolygon *	toCurvePolygon () const
	Down-cast to OGRCurvePolygon*. More...

OGRGeometryCollection *	toGeometryCollection ()
	Down-cast to OGRGeometryCollection*. More...

const OGRGeometryCollection *	toGeometryCollection () const
	Down-cast to OGRGeometryCollection*. More...

OGRMultiPoint *	toMultiPoint ()
	Down-cast to OGRMultiPoint*. More...

const OGRMultiPoint *	toMultiPoint () const
	Down-cast to OGRMultiPoint*. More...

OGRMultiLineString *	toMultiLineString ()
	Down-cast to OGRMultiLineString*. More...

const OGRMultiLineString *	toMultiLineString () const
	Down-cast to OGRMultiLineString*. More...

OGRMultiPolygon *	toMultiPolygon ()
	Down-cast to OGRMultiPolygon*. More...

const OGRMultiPolygon *	toMultiPolygon () const
	Down-cast to OGRMultiPolygon*. More...

OGRMultiCurve *	toMultiCurve ()
	Down-cast to OGRMultiCurve*. More...

const OGRMultiCurve *	toMultiCurve () const
	Down-cast to OGRMultiCurve*. More...

OGRMultiSurface *	toMultiSurface ()
	Down-cast to OGRMultiSurface*. More...

const OGRMultiSurface *	toMultiSurface () const
	Down-cast to OGRMultiSurface*. More...

OGRPolyhedralSurface *	toPolyhedralSurface ()
	Down-cast to OGRPolyhedralSurface*. More...

const OGRPolyhedralSurface *	toPolyhedralSurface () const
	Down-cast to OGRPolyhedralSurface*. More...

OGRTriangulatedSurface *	toTriangulatedSurface ()
	Down-cast to OGRTriangulatedSurface*. More...

const OGRTriangulatedSurface *	toTriangulatedSurface () const
	Down-cast to OGRTriangulatedSurface*. More...

Static Public Member Functions
static OGRCompoundCurve *	CastToCompoundCurve (OGRCurve *puCurve)
	Cast to compound curve. More...

static OGRLineString *	CastToLineString (OGRCurve *poCurve)
	Cast to linestring. More...

static OGRLinearRing *	CastToLinearRing (OGRCurve *poCurve)
	Cast to linear ring. More...

Static Public Member Functions inherited from OGRGeometry
static GEOSContextHandle_t	createGEOSContext ()
	Create a new GEOS context. More...

static void	freeGEOSContext (GEOSContextHandle_t hGEOSCtxt)
	Destroy a GEOS context. More...

static OGRGeometryH	ToHandle (OGRGeometry *poGeom)
	Convert a OGRGeometry* to a OGRGeometryH. More...

static OGRGeometry *	FromHandle (OGRGeometryH hGeom)
	Convert a OGRGeometryH to a OGRGeometry*. More...

Protected Member Functions
virtual int	ContainsPoint (const OGRPoint *p) const
	Returns if a point is contained in a (closed) curve. More...

virtual int	IntersectsPoint (const OGRPoint *p) const
	Returns if a point intersects a (closed) curve. More...

virtual double	get_AreaOfCurveSegments () const =0
	Get the area of the purely curve portions of a (closed) curve. More...

Friends
ConstIterator	begin (const OGRCurve *)

ConstIterator	end (const OGRCurve *)

Detailed Description

Abstract curve base class for OGRLineString, OGRCircularString and OGRCompoundCurve.

Member Typedef Documentation

◆ ChildType

typedef OGRPoint OGRCurve::ChildType

Type of child elements.

Member Function Documentation

◆ begin()

OGRCurve::ConstIterator OGRCurve::begin ( ) const

Return begin of a point iterator.

Using this iterator for standard range-based loops is safe, but due to implementation limitations, you shouldn't try to access (dereference) more than one iterator step at a time, since you will get a reference to the same OGRPoint& object.

Since: GDAL 2.3

◆ CastToCompoundCurve()

OGRCompoundCurve * OGRCurve::CastToCompoundCurve ( OGRCurve * poCurve )

static

Cast to compound curve.

The passed in geometry is consumed and a new one returned (or NULL in case of failure)

Parameters

poCurve the input geometry - ownership is passed to the method.

Returns: new geometry

Since: GDAL 2.0

◆ CastToLinearRing()

OGRLinearRing * OGRCurve::CastToLinearRing ( OGRCurve * poCurve )

static

Cast to linear ring.

The passed in geometry is consumed and a new one returned (or NULL in case of failure)

Parameters

poCurve the input geometry - ownership is passed to the method.

Returns: new geometry.

Since: GDAL 2.0

◆ CastToLineString()

OGRLineString * OGRCurve::CastToLineString ( OGRCurve * poCurve )

static

Cast to linestring.

The passed in geometry is consumed and a new one returned (or NULL in case of failure)

Parameters

poCurve the input geometry - ownership is passed to the method.

Returns: new geometry.

Since: GDAL 2.0

◆ ContainsPoint()

int OGRCurve::ContainsPoint ( const OGRPoint * p ) const

protectedvirtual

Returns if a point is contained in a (closed) curve.

Final users should use OGRGeometry::Contains() instead.

Parameters

p	the point to test

Returns: TRUE if it is inside the curve, FALSE otherwise or -1 if unknown.

Since: GDAL 2.0

◆ CurveToLine()

OGRLineString * OGRCurve::CurveToLine	(	double	dfMaxAngleStepSizeDegrees = `0`,
		const char const	papszOptions = `nullptr`
	)		const

pure virtual

Return a linestring from a curve geometry.

The returned geometry is a new instance whose ownership belongs to the caller.

If the dfMaxAngleStepSizeDegrees is zero, then a default value will be used. This is currently 4 degrees unless the user has overridden the value with the OGR_ARC_STEPSIZE configuration variable.

This method relates to the ISO SQL/MM Part 3 ICurve::CurveToLine() method.

This function is the same as C function OGR_G_CurveToLine().

Parameters

dfMaxAngleStepSizeDegrees	the largest step in degrees along the arc, zero to use the default setting.
papszOptions	options as a null-terminated list of strings or NULL. See OGRGeometryFactory::curveToLineString() for valid options.

Returns: a line string approximating the curve

Since: GDAL 2.0

Implemented in OGRCompoundCurve, OGRCircularString, and OGRLineString.

◆ end()

OGRCurve::ConstIterator OGRCurve::end ( ) const

Return end of a point iterator.

◆ EndPoint()

void OGRCurve::EndPoint ( OGRPoint * poPoint ) const

pure virtual

Return the curve end point.

This method relates to the SF COM ICurve::get_EndPoint() method.

Parameters

poPoint the point to be assigned the end location.

Implemented in OGRCompoundCurve, and OGRSimpleCurve.

◆ get_Area()

double OGRCurve::get_Area ( ) const

pure virtual

Get the area of the (closed) curve.

This method is designed to be used by OGRCurvePolygon::get_Area().

Returns: the area of the feature in square units of the spatial reference system in use.

Since: GDAL 2.0

Implemented in OGRCompoundCurve, OGRCircularString, and OGRLineString.

◆ get_AreaOfCurveSegments()

double OGRCurve::get_AreaOfCurveSegments ( ) const

protectedpure virtual

Get the area of the purely curve portions of a (closed) curve.

This method is designed to be used on a closed convex curve.

Returns: the area of the feature in square units of the spatial reference system in use.

Since: GDAL 2.0

Implemented in OGRCompoundCurve.

◆ get_IsClosed()

int OGRCurve::get_IsClosed ( ) const

virtual

Return TRUE if curve is closed.

Tests if a curve is closed. A curve is closed if its start point is equal to its end point.

For equality tests, the M dimension is ignored.

This method relates to the SFCOM ICurve::get_IsClosed() method.

Returns: TRUE if closed, else FALSE.

◆ get_Length()

double OGRCurve::get_Length ( ) const

pure virtual

Returns the length of the curve.

This method relates to the SFCOM ICurve::get_Length() method.

Returns: the length of the curve, zero if the curve hasn't been initialized.

Implemented in OGRCompoundCurve, OGRCircularString, and OGRSimpleCurve.

◆ getDimension()

int OGRCurve::getDimension ( ) const

overridevirtual

Get the dimension of this object.

This method corresponds to the SFCOM IGeometry::GetDimension() method. It indicates the dimension of the object, but does not indicate the dimension of the underlying space (as indicated by OGRGeometry::getCoordinateDimension()).

This method is the same as the C function OGR_G_GetDimension().

Returns: 0 for points, 1 for lines and 2 for surfaces.

Implements OGRGeometry.

◆ getNumPoints()

int OGRCurve::getNumPoints ( ) const

pure virtual

Return the number of points of a curve geometry.

This method, as a method of OGRCurve, does not relate to a standard. For circular strings or linestrings, it returns the number of points, conforming to SF COM NumPoints(). For compound curves, it returns the sum of the number of points of each of its components (non including intermediate starting/ending points of the different parts).

Returns: the number of points of the curve.

Since: GDAL 2.0

Implemented in OGRCompoundCurve, and OGRSimpleCurve.

◆ getPointIterator()

OGRPointIterator * OGRCurve::getPointIterator ( ) const

pure virtual

Returns a point iterator over the curve.

The curve must not be modified while an iterator exists on it.

The iterator must be destroyed with OGRPointIterator::destroy().

Returns: a point iterator over the curve.

Since: GDAL 2.0

Implemented in OGRCompoundCurve, and OGRSimpleCurve.

◆ IntersectsPoint()

int OGRCurve::IntersectsPoint ( const OGRPoint * p ) const

protectedvirtual

Returns if a point intersects a (closed) curve.

Final users should use OGRGeometry::Intersects() instead.

Parameters

p	the point to test

Returns: TRUE if it intersects the curve, FALSE otherwise or -1 if unknown.

Since: GDAL 2.3

◆ IsConvex()

OGRBoolean OGRCurve::IsConvex ( ) const

virtual

Returns if a (closed) curve forms a convex shape.

Returns: TRUE if the curve forms a convex shape.

Since: GDAL 2.0

◆ StartPoint()

void OGRCurve::StartPoint ( OGRPoint * poPoint ) const

pure virtual

Return the curve start point.

This method relates to the SF COM ICurve::get_StartPoint() method.

Parameters

poPoint the point to be assigned the start location.

Implemented in OGRCompoundCurve, and OGRSimpleCurve.

◆ toSimpleCurve() [1/2]

OGRSimpleCurve* OGRCurve::toSimpleCurve ( )

inline

Down-cast to OGRSimpleCurve*.

Implies prior checking that wkbFlatten(getGeometryType()) == wkbLineString or wkbCircularString.

◆ toSimpleCurve() [2/2]

const OGRSimpleCurve* OGRCurve::toSimpleCurve ( ) const

inline

Down-cast to OGRSimpleCurve*.

Implies prior checking that wkbFlatten(getGeometryType()) == wkbLineString or wkbCircularString.

◆ Value()

void OGRCurve::Value	(	double	dfDistance,
		OGRPoint *	poPoint
	)		const

pure virtual

Fetch point at given distance along curve.

This method relates to the SF COM ICurve::get_Value() method.

This function is the same as the C function OGR_G_Value().

Parameters

dfDistance	distance along the curve at which to sample position. This distance should be between zero and get_Length() for this curve.
poPoint	the point to be assigned the curve position.

Implemented in OGRCompoundCurve, OGRCircularString, and OGRSimpleCurve.

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

ogr_geometry.h
ogrcurve.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ ChildType

Member Function Documentation

◆ begin()

◆ CastToCompoundCurve()

◆ CastToLinearRing()

◆ CastToLineString()

◆ ContainsPoint()

◆ CurveToLine()

◆ end()

◆ EndPoint()

◆ get_Area()

◆ get_AreaOfCurveSegments()

◆ get_IsClosed()

◆ get_Length()

◆ getDimension()

◆ getNumPoints()

◆ getPointIterator()

◆ IntersectsPoint()

◆ IsConvex()

◆ StartPoint()

◆ toSimpleCurve() [1/2]

◆ toSimpleCurve() [2/2]

◆ Value()