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Public Member Functions | Static Protected Member Functions | List of all members
OGRLinearRing Class Reference

Concrete representation of a closed ring. More...

#include <ogr_geometry.h>

Inheritance diagram for OGRLinearRing:
OGRLineString OGRSimpleCurve OGRCurve OGRGeometry

Public Member Functions

 OGRLinearRing ()
 Constructor.
 
 OGRLinearRing (const OGRLinearRing &other)
 Copy constructor. More...
 
 OGRLinearRing (OGRLinearRing *)
 Constructor. More...
 
OGRLinearRingoperator= (const OGRLinearRing &other)
 Assignment operator. More...
 
virtual const char * getGeometryName () const CPL_OVERRIDE
 Fetch WKT name for geometry type. More...
 
virtual OGRGeometryclone () const CPL_OVERRIDE
 Make a copy of this object. More...
 
virtual int isClockwise () const
 Returns TRUE if the ring has clockwise winding (or less than 2 points) More...
 
virtual void reverseWindingOrder ()
 Reverse order of points.
 
virtual void closeRings () CPL_OVERRIDE
 Force rings to be closed. More...
 
OGRBoolean isPointInRing (const OGRPoint *pt, int bTestEnvelope=TRUE) const
 Returns whether the point is inside the ring. More...
 
OGRBoolean isPointOnRingBoundary (const OGRPoint *pt, int bTestEnvelope=TRUE) const
 Returns whether the point is on the ring boundary. More...
 
virtual OGRErr transform (OGRCoordinateTransformation *poCT) CPL_OVERRIDE
 Apply arbitrary coordinate transformation to geometry. 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...
 
- Public Member Functions inherited from OGRLineString
 OGRLineString ()
 Create an empty line string.
 
 OGRLineString (const OGRLineString &other)
 Copy constructor. More...
 
OGRLineStringoperator= (const OGRLineString &other)
 Assignment operator. More...
 
virtual OGRLineStringCurveToLine (double dfMaxAngleStepSizeDegrees=0, const char *const *papszOptions=NULL) const CPL_OVERRIDE
 Return a linestring from a curve geometry. More...
 
virtual OGRGeometrygetCurveGeometry (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...
 
- Public Member Functions inherited from OGRSimpleCurve
OGRSimpleCurveoperator= (const OGRSimpleCurve &other)
 Assignment operator. 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 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 OGRLineStringgetSubLine (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 OGRPointIteratorgetPointIterator () const CPL_OVERRIDE
 Returns a point iterator over the curve. 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...
 
OGRGeometryoperator= (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 OGRGeometrygetLinearGeometry (double dfMaxAngleStepSizeDegrees=0, const char *const *papszOptions=NULL) const CPL_WARN_UNUSED_RESULT
 Return, possibly approximate, non-curve version of this geometry. More...
 
void assignSpatialReference (OGRSpatialReference *poSR)
 Assign spatial reference to this object. More...
 
OGRSpatialReferencegetSpatialReference (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 OGRGeometryBoundary () const CPL_WARN_UNUSED_RESULT
 Compute boundary. More...
 
virtual double Distance (const OGRGeometry *) const
 Compute distance between two geometries. More...
 
virtual OGRGeometryConvexHull () const CPL_WARN_UNUSED_RESULT
 Compute convex hull. More...
 
virtual OGRGeometryBuffer (double dfDist, int nQuadSegs=30) const CPL_WARN_UNUSED_RESULT
 Compute buffer of geometry. More...
 
virtual OGRGeometryIntersection (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
 Compute intersection. More...
 
virtual OGRGeometryUnion (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
 Compute union. More...
 
virtual OGRGeometryUnionCascaded () const CPL_WARN_UNUSED_RESULT
 Compute union using cascading. More...
 
virtual OGRGeometryDifference (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
 Compute difference. More...
 
virtual OGRGeometrySymDifference (const OGRGeometry *) const CPL_WARN_UNUSED_RESULT
 Compute symmetric difference. More...
 
virtual OGRErr Centroid (OGRPoint *poPoint) const
 Compute the geometry centroid. More...
 
virtual OGRGeometrySimplify (double dTolerance) const CPL_WARN_UNUSED_RESULT
 Simplify the geometry. More...
 
OGRGeometrySimplifyPreserveTopology (double dTolerance) const CPL_WARN_UNUSED_RESULT
 Simplify the geometry while preserving topology. More...
 
virtual OGRGeometryDelaunayTriangulation (double dfTolerance, int bOnlyEdges) const CPL_WARN_UNUSED_RESULT
 Return a Delaunay triangulation of the vertices of the geometry. More...
 
virtual OGRGeometryPolygonize () 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 OGRLineStringCastToLineString (OGRLinearRing *poLR)
 Cast to line string. More...
 
- Static Protected Member Functions inherited from OGRLineString
static OGRLinearRingCastToLinearRing (OGRLineString *poLS)
 Cast to linear ring. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from OGRCurve
static OGRCompoundCurveCastToCompoundCurve (OGRCurve *puCurve)
 Cast to compound curve. More...
 
static OGRLineStringCastToLineString (OGRCurve *poCurve)
 Cast to linestring. More...
 
static OGRLinearRingCastToLinearRing (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 closed ring.

This class is functionally equivalent to an OGRLineString, but has a separate identity to maintain alignment with the OpenGIS simple feature data model. It exists to serve as a component of an OGRPolygon.

The OGRLinearRing has no corresponding free standing well known binary representation, so importFromWkb() and exportToWkb() will not actually work. There is a non-standard GDAL WKT representation though.

Because OGRLinearRing is not a "proper" free standing simple features object, it cannot be directly used on a feature via SetGeometry(), and cannot generally be used with GEOS for operations like Intersects(). Instead the polygon should be used, or the OGRLinearRing should be converted to an OGRLineString for such operations.

Note: this class exists in SFSQL 1.2, but not in ISO SQL/MM Part 3.

Constructor & Destructor Documentation

OGRLinearRing::OGRLinearRing ( const OGRLinearRing 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
OGRLinearRing::OGRLinearRing ( OGRLinearRing poSrcRing)
explicit

Constructor.

Parameters
poSrcRingsource ring.

Member Function Documentation

OGRLineString * OGRLinearRing::CastToLineString ( OGRLinearRing poLR)
staticprotected

Cast to line string.

The passed in geometry is consumed and a new one returned .

Parameters
poLRthe input geometry - ownership is passed to the method.
Returns
new geometry.
OGRGeometry * OGRLinearRing::clone ( ) const
virtual

Make a copy of this object.

This method relates to the SFCOM IGeometry::clone() method.

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

Returns
a new object instance with the same geometry, and spatial reference system as the original.

Reimplemented from OGRSimpleCurve.

void OGRLinearRing::closeRings ( )
virtual

Force rings to be closed.

If this geometry, or any contained geometries has polygon rings that are not closed, they will be closed by adding the starting point at the end.

Reimplemented from OGRGeometry.

OGRErr OGRLinearRing::exportToWkb ( OGRwkbByteOrder  eByteOrder,
unsigned char *  pabyData,
OGRwkbVariant  eWkbVariant = wkbVariantOldOgc 
) const
virtual

Convert a geometry into well known binary format.

This method relates to the SFCOM IWks::ExportToWKB() method.

This method is the same as the C function OGR_G_ExportToWkb() or OGR_G_ExportToIsoWkb(), depending on the value of eWkbVariant.

Parameters
eByteOrderOne of wkbXDR or wkbNDR indicating MSB or LSB byte order respectively.
pabyDataa buffer into which the binary representation is written. This buffer must be at least OGRGeometry::WkbSize() byte in size.
eWkbVariantWhat standard to use when exporting geometries with three dimensions (or more). The default wkbVariantOldOgc is the historical OGR variant. wkbVariantIso is the variant defined in ISO SQL/MM and adopted by OGC for SFSQL 1.2.
Returns
Currently OGRERR_NONE is always returned.

Reimplemented from OGRSimpleCurve.

const char * OGRLinearRing::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.

Reimplemented from OGRLineString.

OGRErr OGRLinearRing::importFromWkb ( unsigned char *  pabyData,
int  nSize = -1,
OGRwkbVariant  eWkbVariant = wkbVariantOldOgc 
)
virtual

Assign geometry from well known binary data.

The object must have already been instantiated as the correct derived type of geometry object to match the binaries type. This method is used by the OGRGeometryFactory class, but not normally called by application code.

This method relates to the SFCOM IWks::ImportFromWKB() method.

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

Parameters
pabyDatathe binary input data.
nSizethe size of pabyData in bytes, or zero if not known.
eWkbVariantif wkbVariantPostGIS1, special interpretation is done for curve geometries code
Returns
OGRERR_NONE if all goes well, otherwise any of OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or OGRERR_CORRUPT_DATA may be returned.

Reimplemented from OGRSimpleCurve.

int OGRLinearRing::isClockwise ( ) const
virtual

Returns TRUE if the ring has clockwise winding (or less than 2 points)

Returns
TRUE if clockwise otherwise FALSE.
OGRBoolean OGRLinearRing::isPointInRing ( const OGRPoint poPoint,
int  bTestEnvelope = TRUE 
) const

Returns whether the point is inside the ring.

Parameters
poPointpoint
bTestEnvelopeset to TRUE if the presence of the point inside the ring envelope must be checked first.
Returns
TRUE or FALSE.
OGRBoolean OGRLinearRing::isPointOnRingBoundary ( const OGRPoint poPoint,
int  bTestEnvelope = TRUE 
) const

Returns whether the point is on the ring boundary.

Parameters
poPointpoint
bTestEnvelopeset to TRUE if the presence of the point inside the ring envelope must be checked first.
Returns
TRUE or FALSE.
OGRLinearRing & OGRLinearRing::operator= ( const OGRLinearRing 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
OGRErr OGRLinearRing::transform ( OGRCoordinateTransformation poCT)
virtual

Apply arbitrary coordinate transformation to geometry.

This method will transform the coordinates of a geometry from their current spatial reference system to a new target spatial reference system. Normally this means reprojecting the vectors, but it could include datum shifts, and changes of units.

Note that this method does not require that the geometry already have a spatial reference system. It will be assumed that they can be treated as having the source spatial reference system of the OGRCoordinateTransformation object, and the actual SRS of the geometry will be ignored. On successful completion the output OGRSpatialReference of the OGRCoordinateTransformation will be assigned to the geometry.

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

Parameters
poCTthe transformation to apply.
Returns
OGRERR_NONE on success or an error code.

Reimplemented from OGRSimpleCurve.

int OGRLinearRing::WkbSize ( ) const
virtual

Returns size of related binary representation.

This method returns the exact number of bytes required to hold the well known binary representation of this geometry object. Its computation may be slightly expensive for complex geometries.

This method relates to the SFCOM IWks::WkbSize() method.

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

Returns
size of binary representation in bytes.

Reimplemented from OGRSimpleCurve.


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

Generated for GDAL by doxygen 1.8.8.