OGRLineString Class Reference

Concrete representation of a multi-vertex line. More...

#include <ogr_geometry.h>

Inheritance diagram for OGRLineString:

Public Member Functions
	OGRLineString ()
	Create an empty line string.
	OGRLineString (const OGRLineString &other)
	Copy constructor. More...
OGRLineString &	operator= (const OGRLineString &other)
	Assignment operator. More...
virtual OGRLineString *	CurveToLine (double dfMaxAngleStepSizeDegrees=0, const char *const *papszOptions=NULL) const CPL_OVERRIDE
	Return a linestring from a curve geometry. More...
virtual OGRGeometry *	getCurveGeometry (const char *const *papszOptions=NULL) const CPL_OVERRIDE
	Return curve version of this geometry. More...
virtual double	get_Area () const CPL_OVERRIDE
	Get the area of the (closed) curve. More...
virtual OGRwkbGeometryType	getGeometryType () const CPL_OVERRIDE
	Fetch geometry type. More...
virtual const char *	getGeometryName () const CPL_OVERRIDE
	Fetch WKT name for geometry type. More...
Public Member Functions inherited from OGRSimpleCurve
OGRSimpleCurve &	operator= (const OGRSimpleCurve &other)
	Assignment operator. More...
virtual int	WkbSize () const CPL_OVERRIDE
	Returns size of related binary representation. More...
virtual OGRErr	importFromWkb (unsigned char *, int=-1, OGRwkbVariant=wkbVariantOldOgc) CPL_OVERRIDE
	Assign geometry from well known binary data. More...
virtual OGRErr	exportToWkb (OGRwkbByteOrder, unsigned char *, OGRwkbVariant=wkbVariantOldOgc) const CPL_OVERRIDE
	Convert a geometry into well known binary format. More...
virtual OGRErr	importFromWkt (char **) CPL_OVERRIDE
	Assign geometry from well known text data. More...
virtual OGRErr	exportToWkt (char **ppszDstText, OGRwkbVariant=wkbVariantOldOgc) const CPL_OVERRIDE
	Convert a geometry into well known text format. More...
virtual OGRGeometry *	clone () const CPL_OVERRIDE
	Make a copy of this object. More...
virtual void	empty () CPL_OVERRIDE
	Clear geometry information. More...
virtual void	getEnvelope (OGREnvelope *psEnvelope) const CPL_OVERRIDE
	Computes and returns the bounding envelope for this geometry in the passed psEnvelope structure. More...
virtual void	getEnvelope (OGREnvelope3D *psEnvelope) const CPL_OVERRIDE
	Computes and returns the bounding envelope (3D) for this geometry in the passed psEnvelope structure. More...
virtual OGRBoolean	IsEmpty () const CPL_OVERRIDE
	Returns TRUE (non-zero) if the object has no points. More...
virtual double	get_Length () const CPL_OVERRIDE
	Returns the length of the curve. More...
virtual void	StartPoint (OGRPoint *) const CPL_OVERRIDE
	Return the curve start point. More...
virtual void	EndPoint (OGRPoint *) const CPL_OVERRIDE
	Return the curve end point. More...
virtual void	Value (double, OGRPoint *) const CPL_OVERRIDE
	Fetch point at given distance along curve. More...
virtual double	Project (const OGRPoint *) const
	Project point on linestring. More...
virtual OGRLineString *	getSubLine (double, double, int) const
	Get the portion of linestring. More...
virtual int	getNumPoints () const CPL_OVERRIDE
	Fetch vertex count. More...
void	getPoint (int, OGRPoint *) const
	Fetch a point in line string. More...
double	getX (int i) const
	Get X at vertex. More...
double	getY (int i) const
	Get Y at vertex. More...
double	getZ (int i) const
	Get Z at vertex. More...
double	getM (int i) const
	Get measure at vertex. More...
virtual OGRBoolean	Equals (OGRGeometry *) const CPL_OVERRIDE
	Returns TRUE if two geometries are equivalent. More...
virtual void	setCoordinateDimension (int nDimension) CPL_OVERRIDE
	Set the coordinate dimension. More...
virtual void	set3D (OGRBoolean bIs3D) CPL_OVERRIDE
	Add or remove the Z coordinate dimension. More...
virtual void	setMeasured (OGRBoolean bIsMeasured) CPL_OVERRIDE
	Add or remove the M coordinate dimension. More...
void	setNumPoints (int nNewPointCount, int bZeroizeNewContent=TRUE)
	Set number of points in geometry. More...
void	setPoint (int, OGRPoint *)
	Set the location of a vertex in line string. More...
void	setPoint (int, double, double)
	Set the location of a vertex in line string. More...
void	setZ (int, double)
	Set the Z of a vertex in line string. More...
void	setM (int, double)
	Set the M of a vertex in line string. More...
void	setPoint (int, double, double, double)
	Set the location of a vertex in line string. More...
void	setPointM (int, double, double, double)
	Set the location of a vertex in line string. More...
void	setPoint (int, double, double, double, double)
	Set the location of a vertex in line string. More...
void	setPoints (int, OGRRawPoint *, double *=NULL)
	Assign all points in a line string. More...
void	setPointsM (int, OGRRawPoint *, double *)
	Assign all points in a line string. More...
void	setPoints (int, OGRRawPoint *, double *, double *)
	Assign all points in a line string. More...
void	setPoints (int, double *padfX, double *padfY, double *padfZIn=NULL)
	Assign all points in a line string. More...
void	setPointsM (int, double *padfX, double *padfY, double *padfMIn=NULL)
	Assign all points in a line string. More...
void	setPoints (int, double *padfX, double *padfY, double *padfZIn, double *padfMIn)
	Assign all points in a line string. More...
void	addPoint (const OGRPoint *)
	Add a point to a line string. More...
void	addPoint (double, double)
	Add a point to a line string. More...
void	addPoint (double, double, double)
	Add a point to a line string. More...
void	addPointM (double, double, double)
	Add a point to a line string. More...
void	addPoint (double, double, double, double)
	Add a point to a line string. More...
void	getPoints (OGRRawPoint *, double *=NULL) const
	Returns all points of line string. More...
void	getPoints (void *pabyX, int nXStride, void *pabyY, int nYStride, void *pabyZ=NULL, int nZStride=0) const
	Returns all points of line string. More...
void	getPoints (void *pabyX, int nXStride, void *pabyY, int nYStride, void *pabyZ, int nZStride, void *pabyM, int nMStride) const
	Returns all points of line string. More...
void	addSubLineString (const OGRLineString *, int nStartVertex=0, int nEndVertex=-1)
	Add a segment of another linestring to this one. More...
void	reversePoints (void)
	Reverse point order. More...
virtual OGRPointIterator *	getPointIterator () const CPL_OVERRIDE
	Returns a point iterator over the curve. More...
virtual OGRErr	transform (OGRCoordinateTransformation *poCT) CPL_OVERRIDE
	Apply arbitrary coordinate transformation to geometry. More...
virtual void	flattenTo2D () CPL_OVERRIDE
	Convert geometry to strictly 2D. More...
virtual void	segmentize (double dfMaxLength) CPL_OVERRIDE
	Modify the geometry such it has no segment longer then the given distance. More...
virtual void	swapXY () CPL_OVERRIDE
	Swap x and y coordinates. More...
Public Member Functions inherited from OGRCurve
virtual int	get_IsClosed () const
	Return TRUE if curve is closed. More...
virtual int	getDimension () const CPL_OVERRIDE
	Get the dimension of this object. More...
virtual OGRBoolean	IsConvex () const
	Returns if a (closed) curve forms a convex shape. More...
Public Member Functions inherited from OGRGeometry
	OGRGeometry (const OGRGeometry &other)
	Copy constructor. More...
OGRGeometry &	operator= (const OGRGeometry &other)
	Assignment operator. 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	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...
OGRwkbGeometryType	getIsoGeometryType () const
	Get the geometry type that conforms with ISO SQL/MM Part3. More...
virtual void	dumpReadable (FILE *, const char *=NULL, char **papszOptions=NULL) const
	Dump geometry in well known text format to indicated output file. More...
virtual char *	exportToGML (const char *const *papszOptions=NULL) 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 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 *	getLinearGeometry (double dfMaxAngleStepSizeDegrees=0, const char *const *papszOptions=NULL) const CPL_WARN_UNUSED_RESULT
	Return, possibly approximate, non-curve version of this geometry. More...
virtual void	closeRings ()
	Force rings to be closed. More...
void	assignSpatialReference (OGRSpatialReference *poSR)
	Assign spatial reference to this object. More...
OGRSpatialReference *	getSpatialReference (void) const
	Returns spatial reference system for object. More...
OGRErr	transformTo (OGRSpatialReference *poSR)
	Transform geometry to new spatial reference system. More...
virtual OGRBoolean	Intersects (const OGRGeometry *) const
	Do these features intersect? 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...

Static Protected Member Functions
static OGRLinearRing *	CastToLinearRing (OGRLineString *poLS)
	Cast to linear ring. More...

Additional Inherited Members
Static Public Member Functions inherited from OGRCurve
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...
Protected Member Functions inherited from OGRSimpleCurve
virtual double	get_LinearArea () const
	Compute area of ring / closed linestring. More...
	OGRSimpleCurve ()
	Constructor.
	OGRSimpleCurve (const OGRSimpleCurve &other)
	Copy constructor. More...
Protected Member Functions inherited from OGRCurve
virtual int	ContainsPoint (const OGRPoint *p) const
	Returns if a point is contained in a (closed) curve. More...
virtual double	get_AreaOfCurveSegments () const =0
	Get the area of the purely curve portions of a (closed) curve. More...

Detailed Description

Concrete representation of a multi-vertex line.

Note: for implementation convenience, we make it inherit from OGRSimpleCurve whereas SFSQL and SQL/MM only make it inherits from OGRCurve.

Constructor & Destructor Documentation

OGRLineString()

OGRLineString::OGRLineString

(

const OGRLineString &

other

)

Copy constructor.

Note: before GDAL 2.1, only the default implementation of the constructor existed, which could be unsafe to use.

Since

GDAL 2.1

Member Function Documentation

CastToLinearRing()

OGRLinearRing * OGRLineString::CastToLinearRing ( OGRLineString *  poLS )

staticprotected

Cast to linear ring.

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

Parameters

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

Returns

new geometry.

CurveToLine()

OGRLineString * OGRLineString::CurveToLine ( double  dfMaxAngleStepSizeDegrees = 0, const char *const *  papszOptions = NULL  ) const

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

Implements OGRCurve.

get_Area()

virtual double OGRLineString::get_Area ( ) const

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

Implements OGRCurve.

getCurveGeometry()

OGRGeometry * OGRLineString::getCurveGeometry ( const char *const *  papszOptions = NULL ) const

virtual

Return curve version of this geometry.

Returns a geometry that has possibly CIRCULARSTRING, COMPOUNDCURVE, CURVEPOLYGON, MULTICURVE or MULTISURFACE in it, by de-approximating curve geometries.

If the geometry has no curve portion, the returned geometry will be a clone of it.

The ownership of the returned geometry belongs to the caller.

The reverse method is OGRGeometry::getLinearGeometry().

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

Parameters

papszOptions

options as a null-terminated list of strings. Unused for now. Must be set to NULL.

Returns

a new geometry.

Since

GDAL 2.0

Reimplemented from OGRGeometry.

getGeometryName()

const char * OGRLineString::getGeometryName ( ) const

virtual

Fetch WKT name for geometry type.

There is no SFCOM analog to this method.

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

Returns

name used for this geometry type in well known text format. The returned pointer is to a static internal string and should not be modified or freed.

Implements OGRGeometry.

Reimplemented in OGRLinearRing.

getGeometryType()

OGRwkbGeometryType OGRLineString::getGeometryType ( ) const

virtual

Fetch geometry type.

Note that the geometry type may include the 2.5D flag. To get a 2D flattened version of the geometry type apply the wkbFlatten() macro to the return result.

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

Returns

the geometry type code.

Implements OGRGeometry.

operator=()

OGRLineString & OGRLineString::operator=

(

const OGRLineString &

other

)

Assignment operator.

Note: before GDAL 2.1, only the default implementation of the operator existed, which could be unsafe to use.

Since

GDAL 2.1

---

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

• ogr_geometry.h
• ogrlinestring.cpp