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QgsGeometry Class Reference

#include <qgsgeometry.h>

Classes

class  Error
 

Public Member Functions

 QgsGeometry ()
 Constructor. More...
 
 QgsGeometry (const QgsGeometry &)
 copy constructor will prompt a deep copy of the object More...
 
QgsGeometryoperator= (QgsGeometry const &rhs)
 assignments will prompt a deep copy of the object More...
 
 ~QgsGeometry ()
 Destructor. More...
 
void fromGeos (GEOSGeometry *geos)
 Set the geometry, feeding in a geometry in GEOS format. More...
 
void fromWkb (unsigned char *wkb, size_t length)
 Set the geometry, feeding in the buffer containing OGC Well-Known Binary and the buffer's length. More...
 
const unsigned char * asWkb () const
 Returns the buffer containing this geometry in WKB format. More...
 
size_t wkbSize () const
 Returns the size of the WKB in asWkb(). More...
 
const GEOSGeometry * asGeos () const
 Returns a geos geomtry. More...
 
QGis::WkbType wkbType () const
 Returns type of wkb (point / linestring / polygon etc.) More...
 
QGis::GeometryType type ()
 Returns type of the vector. More...
 
bool isMultipart ()
 Returns true if wkb of the geometry is of WKBMulti* type. More...
 
bool isGeosEqual (QgsGeometry &)
 compare geometries using GEOS More...
 
bool isGeosValid ()
 check validity using GEOS More...
 
bool isGeosEmpty ()
 check if geometry is empty using GEOS More...
 
double area ()
 get area of geometry using GEOS More...
 
double length ()
 get length of geometry using GEOS More...
 
double distance (QgsGeometry &geom)
 
QgsPoint closestVertex (const QgsPoint &point, int &atVertex, int &beforeVertex, int &afterVertex, double &sqrDist)
 Returns the vertex closest to the given point, the corresponding vertex index, squared distance snap point / target point and the indices of the vertices before/after. More...
 
void adjacentVertices (int atVertex, int &beforeVertex, int &afterVertex)
 Returns the indexes of the vertices before and after the given vertex index. More...
 
bool insertVertex (double x, double y, int beforeVertex)
 Insert a new vertex before the given vertex index, ring and item (first number is index 0) If the requested vertex number (beforeVertex.back()) is greater than the last actual vertex on the requested ring and item, it is assumed that the vertex is to be appended instead of inserted. More...
 
bool moveVertex (double x, double y, int atVertex)
 Moves the vertex at the given position number and item (first number is index 0) to the given coordinates. More...
 
bool deleteVertex (int atVertex)
 Deletes the vertex at the given position number and item (first number is index 0) Returns false if atVertex does not correspond to a valid vertex on this geometry (including if this geometry is a Point), or if the number of remaining verticies in the linestring would be less than two. More...
 
QgsPoint vertexAt (int atVertex)
 Returns coordinates of a vertex. More...
 
double sqrDistToVertexAt (QgsPoint &point, int atVertex)
 Returns the squared cartesian distance between the given point to the given vertex index (vertex at the given position number, ring and item (first number is index 0)) More...
 
double closestVertexWithContext (const QgsPoint &point, int &atVertex)
 Searches for the closest vertex in this geometry to the given point. More...
 
double closestSegmentWithContext (const QgsPoint &point, QgsPoint &minDistPoint, int &afterVertex, double *leftOf=0, double epsilon=DEFAULT_SEGMENT_EPSILON)
 Searches for the closest segment of geometry to the given point. More...
 
int addRing (const QList< QgsPoint > &ring)
 Adds a new ring to this geometry. More...
 
int addPart (const QList< QgsPoint > &points, QGis::GeometryType geomType=QGis::UnknownGeometry)
 Adds a new island polygon to a multipolygon feature. More...
 
int addPart (GEOSGeometry *newPart)
 Adds a new island polygon to a multipolygon feature. More...
 
int addPart (QgsGeometry *newPart)
 Adds a new island polygon to a multipolygon feature. More...
 
int translate (double dx, double dy)
 Translate this geometry by dx, dy. More...
 
int transform (const QgsCoordinateTransform &ct)
 Transform this geometry as described by CoordinateTranasform ct. More...
 
int splitGeometry (const QList< QgsPoint > &splitLine, QList< QgsGeometry * > &newGeometries, bool topological, QList< QgsPoint > &topologyTestPoints)
 Splits this geometry according to a given line. More...
 
int reshapeGeometry (const QList< QgsPoint > &reshapeWithLine)
 Replaces a part of this geometry with another line. More...
 
int makeDifference (QgsGeometry *other)
 Changes this geometry such that it does not intersect the other geometry. More...
 
QgsRectangle boundingBox ()
 Returns the bounding box of this feature. More...
 
bool intersects (const QgsRectangle &r) const
 Test for intersection with a rectangle (uses GEOS) More...
 
bool intersects (const QgsGeometry *geometry) const
 Test for intersection with a geometry (uses GEOS) More...
 
bool contains (const QgsPoint *p) const
 Test for containment of a point (uses GEOS) More...
 
bool contains (const QgsGeometry *geometry) const
 Test for if geometry is contained in another (uses GEOS) More...
 
bool disjoint (const QgsGeometry *geometry) const
 Test for if geometry is disjoint of another (uses GEOS) More...
 
bool equals (const QgsGeometry *geometry) const
 Test for if geometry equals another (uses GEOS) More...
 
bool touches (const QgsGeometry *geometry) const
 Test for if geometry touch another (uses GEOS) More...
 
bool overlaps (const QgsGeometry *geometry) const
 Test for if geometry overlaps another (uses GEOS) More...
 
bool within (const QgsGeometry *geometry) const
 Test for if geometry is within another (uses GEOS) More...
 
bool crosses (const QgsGeometry *geometry) const
 Test for if geometry crosses another (uses GEOS) More...
 
QgsGeometrybuffer (double distance, int segments)
 Returns a buffer region around this geometry having the given width and with a specified number of segments used to approximate curves. More...
 
QgsGeometrybuffer (double distance, int segments, int endCapStyle, int joinStyle, double mitreLimit)
 Returns a buffer region around the geometry, with additional style options. More...
 
QgsGeometryoffsetCurve (double distance, int segments, int joinStyle, double mitreLimit)
 Returns an offset line at a given distance and side from an input line. More...
 
QgsGeometrysimplify (double tolerance)
 Returns a simplified version of this geometry using a specified tolerance value. More...
 
QgsGeometrycentroid ()
 Returns the center of mass of a geometry. More...
 
QgsGeometrypointOnSurface ()
 Returns a point within a geometry. More...
 
QgsGeometryconvexHull ()
 Returns the smallest convex polygon that contains all the points in the geometry. More...
 
QgsGeometryinterpolate (double distance)
 
QgsGeometryintersection (QgsGeometry *geometry)
 Returns a geometry representing the points shared by this geometry and other. More...
 
QgsGeometrycombine (QgsGeometry *geometry)
 Returns a geometry representing all the points in this geometry and other (a union geometry operation). More...
 
QgsGeometrydifference (QgsGeometry *geometry)
 Returns a geometry representing the points making up this geometry that do not make up other. More...
 
QgsGeometrysymDifference (QgsGeometry *geometry)
 Returns a Geometry representing the points making up this Geometry that do not make up other. More...
 
QString exportToWkt (const int &precision=17) const
 Exports the geometry to WKT. More...
 
QString exportToGeoJSON (const int &precision=17) const
 Exports the geometry to GeoJSON. More...
 
QgsGeometryconvertToType (QGis::GeometryType destType, bool destMultipart=false)
 try to convert the geometry to the requested type More...
 
QgsPoint asPoint () const
 return contents of the geometry as a point if wkbType is WKBPoint, otherwise returns [0,0] More...
 
QgsPolyline asPolyline () const
 return contents of the geometry as a polyline if wkbType is WKBLineString, otherwise an empty list More...
 
QgsPolygon asPolygon () const
 return contents of the geometry as a polygon if wkbType is WKBPolygon, otherwise an empty list More...
 
QgsMultiPoint asMultiPoint () const
 return contents of the geometry as a multi point if wkbType is WKBMultiPoint, otherwise an empty list More...
 
QgsMultiPolyline asMultiPolyline () const
 return contents of the geometry as a multi linestring if wkbType is WKBMultiLineString, otherwise an empty list More...
 
QgsMultiPolygon asMultiPolygon () const
 return contents of the geometry as a multi polygon if wkbType is WKBMultiPolygon, otherwise an empty list More...
 
QList< QgsGeometry * > asGeometryCollection () const
 return contents of the geometry as a list of geometries More...
 
bool deleteRing (int ringNum, int partNum=0)
 delete a ring in polygon or multipolygon. More...
 
bool deletePart (int partNum)
 delete part identified by the part number More...
 
bool convertToMultiType ()
 Converts single type geometry into multitype geometry e.g. More...
 
int avoidIntersections (QMap< QgsVectorLayer *, QSet< QgsFeatureId > > ignoreFeatures=(QMap< QgsVectorLayer *, QSet< QgsFeatureId > >()))
 Modifies geometry to avoid intersections with the layers specified in project properties. More...
 
void validateGeometry (QList< Error > &errors)
 Validate geometry and produce a list of geometry errors. More...
 

Static Public Member Functions

static GEOSContextHandle_t getGEOSHandler ()
 return GEOS context handle More...
 
static QgsGeometryfromWkt (QString wkt)
 static method that creates geometry from Wkt More...
 
static QgsGeometryfromPoint (const QgsPoint &point)
 construct geometry from a point More...
 
static QgsGeometryfromMultiPoint (const QgsMultiPoint &multipoint)
 construct geometry from a multipoint More...
 
static QgsGeometryfromPolyline (const QgsPolyline &polyline)
 construct geometry from a polyline More...
 
static QgsGeometryfromMultiPolyline (const QgsMultiPolyline &multiline)
 construct geometry from a multipolyline More...
 
static QgsGeometryfromPolygon (const QgsPolygon &polygon)
 construct geometry from a polygon More...
 
static QgsGeometryfromMultiPolygon (const QgsMultiPolygon &multipoly)
 construct geometry from a multipolygon More...
 
static QgsGeometryfromRect (const QgsRectangle &rect)
 construct geometry from a rectangle More...
 
static QgsGeometryunaryUnion (const QList< QgsGeometry * > &geometryList)
 compute the unary union on a list of geometries. More...
 

Constructor & Destructor Documentation

QgsGeometry::QgsGeometry ( )

Constructor.

QgsGeometry::QgsGeometry ( const QgsGeometry rhs)

copy constructor will prompt a deep copy of the object

QgsGeometry::~QgsGeometry ( )

Destructor.

Member Function Documentation

int QgsGeometry::addPart ( const QList< QgsPoint > &  points,
QGis::GeometryType  geomType = QGis::UnknownGeometry 
)

Adds a new island polygon to a multipolygon feature.

Returns
0 in case of success, 1 if not a multipolygon, 2 if ring is not a valid geometry, 3 if new polygon ring not disjoint with existing polygons of the feature
int QgsGeometry::addPart ( GEOSGeometry *  newPart)

Adds a new island polygon to a multipolygon feature.

Returns
0 in case of success, 1 if not a multipolygon, 2 if ring is not a valid geometry, 3 if new polygon ring not disjoint with existing polygons of the feature
Note
not available in python bindings
int QgsGeometry::addPart ( QgsGeometry newPart)

Adds a new island polygon to a multipolygon feature.

Returns
0 in case of success, 1 if not a multipolygon, 2 if ring is not a valid geometry, 3 if new polygon ring not disjoint with existing polygons of the feature
Note
available in python bindings as addPartGeometry (added in 2.2)
int QgsGeometry::addRing ( const QList< QgsPoint > &  ring)

Adds a new ring to this geometry.

This makes only sense for polygon and multipolygons.

Returns
0 in case of success (ring added), 1 problem with geometry type, 2 ring not closed, 3 ring is not valid geometry, 4 ring not disjoint with existing rings, 5 no polygon found which contained the ring
void QgsGeometry::adjacentVertices ( int  atVertex,
int &  beforeVertex,
int &  afterVertex 
)

Returns the indexes of the vertices before and after the given vertex index.

This function takes into account the following factors:

  1. If the given vertex index is at the end of a linestring, the adjacent index will be -1 (for "no adjacent vertex")
  2. If the given vertex index is at the end of a linear ring (such as in a polygon), the adjacent index will take into account the first vertex is equal to the last vertex (and will skip equal vertex positions).
double QgsGeometry::area ( )

get area of geometry using GEOS

Note
added in 1.5
QList< QgsGeometry * > QgsGeometry::asGeometryCollection ( ) const

return contents of the geometry as a list of geometries

Note
added in version 1.1
const GEOSGeometry * QgsGeometry::asGeos ( ) const

Returns a geos geomtry.

QgsGeometry keeps ownership, don't delete the returned object!

Note
this method was added in version 1.1
not available in python bindings
QgsMultiPoint QgsGeometry::asMultiPoint ( ) const

return contents of the geometry as a multi point if wkbType is WKBMultiPoint, otherwise an empty list

QgsMultiPolygon QgsGeometry::asMultiPolygon ( ) const

return contents of the geometry as a multi polygon if wkbType is WKBMultiPolygon, otherwise an empty list

QgsMultiPolyline QgsGeometry::asMultiPolyline ( ) const

return contents of the geometry as a multi linestring if wkbType is WKBMultiLineString, otherwise an empty list

QgsPoint QgsGeometry::asPoint ( ) const

return contents of the geometry as a point if wkbType is WKBPoint, otherwise returns [0,0]

QgsPolygon QgsGeometry::asPolygon ( ) const

return contents of the geometry as a polygon if wkbType is WKBPolygon, otherwise an empty list

QgsPolyline QgsGeometry::asPolyline ( ) const

return contents of the geometry as a polyline if wkbType is WKBLineString, otherwise an empty list

const unsigned char * QgsGeometry::asWkb ( ) const

Returns the buffer containing this geometry in WKB format.

You may wish to use in conjunction with wkbSize().

int QgsGeometry::avoidIntersections ( QMap< QgsVectorLayer *, QSet< QgsFeatureId > >  ignoreFeatures = ( QMap<QgsVectorLayer*, QSet<QgsFeatureId> >() ))

Modifies geometry to avoid intersections with the layers specified in project properties.

Returns
0 in case of success, 1 if geometry is not of polygon type, 2 if avoid intersection would change the geometry type, 3 other error during intersection removal
Parameters
ignoreFeaturespossibility to give a list of features where intersections should be ignored (not available in python bindings)
Note
added in 1.5
QgsRectangle QgsGeometry::boundingBox ( )

Returns the bounding box of this feature.

QgsGeometry * QgsGeometry::buffer ( double  distance,
int  segments 
)

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

QgsGeometry * QgsGeometry::buffer ( double  distance,
int  segments,
int  endCapStyle,
int  joinStyle,
double  mitreLimit 
)

Returns a buffer region around the geometry, with additional style options.

Parameters
distancebuffer distance
segmentsFor round joins, number of segments to approximate quarter-circle
endCapStyleRound (1) / Flat (2) / Square (3) end cap style
joinStyleRound (1) / Mitre (2) / Bevel (3) join style
mitreLimitLimit on the mitre ratio used for very sharp corners
Note
added in 2.4
needs GEOS >= 3.3 - otherwise always returns 0
QgsGeometry * QgsGeometry::centroid ( )

Returns the center of mass of a geometry.

Note
for line based geometries, the center point of the line is returned, and for point based geometries, the point itself is returned
double QgsGeometry::closestSegmentWithContext ( const QgsPoint point,
QgsPoint minDistPoint,
int &  afterVertex,
double *  leftOf = 0,
double  epsilon = DEFAULT_SEGMENT_EPSILON 
)

Searches for the closest segment of geometry to the given point.

Parameters
pointSpecifies the point for search
minDistPointReceives the nearest point on the segment
afterVertexReceives index of the vertex after the closest segment. The vertex before the closest segment is always afterVertex - 1
leftOfOut: Returns if the point lies on the left of right side of the segment ( < 0 means left, > 0 means right )
epsilonepsilon for segment snapping (added in 1.8)
Returns
The squared cartesian distance is also returned in sqrDist, negative number on error
QgsPoint QgsGeometry::closestVertex ( const QgsPoint point,
int &  atVertex,
int &  beforeVertex,
int &  afterVertex,
double &  sqrDist 
)

Returns the vertex closest to the given point, the corresponding vertex index, squared distance snap point / target point and the indices of the vertices before/after.

The vertices before/after are -1 if not present

double QgsGeometry::closestVertexWithContext ( const QgsPoint point,
int &  atVertex 
)

Searches for the closest vertex in this geometry to the given point.

Parameters
pointSpecifiest the point for search
atVertexReceives index of the closest vertex
Returns
The squared cartesian distance is also returned in sqrDist, negative number on error
QgsGeometry * QgsGeometry::combine ( QgsGeometry geometry)

Returns a geometry representing all the points in this geometry and other (a union geometry operation).

Note
this operation is not called union since its a reserved word in C++.
bool QgsGeometry::contains ( const QgsPoint p) const

Test for containment of a point (uses GEOS)

bool QgsGeometry::contains ( const QgsGeometry geometry) const

Test for if geometry is contained in another (uses GEOS)

Note
added in 1.5
bool QgsGeometry::convertToMultiType ( )

Converts single type geometry into multitype geometry e.g.

a polygon into a multipolygon geometry with one polygon

Returns
true in case of success and false else
QgsGeometry * QgsGeometry::convertToType ( QGis::GeometryType  destType,
bool  destMultipart = false 
)

try to convert the geometry to the requested type

Parameters
destTypethe geometry type to be converted to
destMultipartdetermines if the output geometry will be multipart or not
Returns
the converted geometry or NULL pointer if the conversion fails.
Note
added in 2.2
QgsGeometry * QgsGeometry::convexHull ( )

Returns the smallest convex polygon that contains all the points in the geometry.

bool QgsGeometry::crosses ( const QgsGeometry geometry) const

Test for if geometry crosses another (uses GEOS)

Note
added in 1.5
bool QgsGeometry::deletePart ( int  partNum)

delete part identified by the part number

Returns
true on success
Note
added in version 1.2
bool QgsGeometry::deleteRing ( int  ringNum,
int  partNum = 0 
)

delete a ring in polygon or multipolygon.

Ring 0 is outer ring and can't be deleted.

Returns
true on success
Note
added in version 1.2
bool QgsGeometry::deleteVertex ( int  atVertex)

Deletes the vertex at the given position number and item (first number is index 0) Returns false if atVertex does not correspond to a valid vertex on this geometry (including if this geometry is a Point), or if the number of remaining verticies in the linestring would be less than two.

It is up to the caller to distinguish between these error conditions. (Or maybe we add another method to this object to help make the distinction?)

QgsGeometry * QgsGeometry::difference ( QgsGeometry geometry)

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

bool QgsGeometry::disjoint ( const QgsGeometry geometry) const

Test for if geometry is disjoint of another (uses GEOS)

Note
added in 1.5
double QgsGeometry::distance ( QgsGeometry geom)
bool QgsGeometry::equals ( const QgsGeometry geometry) const

Test for if geometry equals another (uses GEOS)

Note
added in 1.5
QString QgsGeometry::exportToGeoJSON ( const int &  precision = 17) const

Exports the geometry to GeoJSON.

Returns
a QString representing the geometry as GeoJSON
Note
added in 1.8
python binding added in 1.9
precision parameter added in 2.4
QString QgsGeometry::exportToWkt ( const int &  precision = 17) const

Exports the geometry to WKT.

Note
precision parameter added in 2.4
Returns
true in case of success and false else
void QgsGeometry::fromGeos ( GEOSGeometry *  geos)

Set the geometry, feeding in a geometry in GEOS format.

This class will take ownership of the buffer.

Note
not available in python bindings
QgsGeometry * QgsGeometry::fromMultiPoint ( const QgsMultiPoint multipoint)
static

construct geometry from a multipoint

QgsGeometry * QgsGeometry::fromMultiPolygon ( const QgsMultiPolygon multipoly)
static

construct geometry from a multipolygon

QgsGeometry * QgsGeometry::fromMultiPolyline ( const QgsMultiPolyline multiline)
static

construct geometry from a multipolyline

QgsGeometry * QgsGeometry::fromPoint ( const QgsPoint point)
static

construct geometry from a point

QgsGeometry * QgsGeometry::fromPolygon ( const QgsPolygon polygon)
static

construct geometry from a polygon

QgsGeometry * QgsGeometry::fromPolyline ( const QgsPolyline polyline)
static

construct geometry from a polyline

QgsGeometry * QgsGeometry::fromRect ( const QgsRectangle rect)
static

construct geometry from a rectangle

void QgsGeometry::fromWkb ( unsigned char *  wkb,
size_t  length 
)

Set the geometry, feeding in the buffer containing OGC Well-Known Binary and the buffer's length.

This class will take ownership of the buffer.

QgsGeometry * QgsGeometry::fromWkt ( QString  wkt)
static

static method that creates geometry from Wkt

GEOSContextHandle_t QgsGeometry::getGEOSHandler ( )
static

return GEOS context handle

Note
added in 2.6
not available in Python
bool QgsGeometry::insertVertex ( double  x,
double  y,
int  beforeVertex 
)

Insert a new vertex before the given vertex index, ring and item (first number is index 0) If the requested vertex number (beforeVertex.back()) is greater than the last actual vertex on the requested ring and item, it is assumed that the vertex is to be appended instead of inserted.

Returns false if atVertex does not correspond to a valid vertex on this geometry (including if this geometry is a Point). It is up to the caller to distinguish between these error conditions. (Or maybe we add another method to this object to help make the distinction?)

QgsGeometry * QgsGeometry::interpolate ( double  distance)
QgsGeometry * QgsGeometry::intersection ( QgsGeometry geometry)

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

bool QgsGeometry::intersects ( const QgsRectangle r) const

Test for intersection with a rectangle (uses GEOS)

bool QgsGeometry::intersects ( const QgsGeometry geometry) const

Test for intersection with a geometry (uses GEOS)

bool QgsGeometry::isGeosEmpty ( )

check if geometry is empty using GEOS

Note
added in 1.5
bool QgsGeometry::isGeosEqual ( QgsGeometry g)

compare geometries using GEOS

Note
added in 1.5
bool QgsGeometry::isGeosValid ( )

check validity using GEOS

Note
added in 1.5
bool QgsGeometry::isMultipart ( )

Returns true if wkb of the geometry is of WKBMulti* type.

double QgsGeometry::length ( )

get length of geometry using GEOS

Note
added in 1.5
int QgsGeometry::makeDifference ( QgsGeometry other)

Changes this geometry such that it does not intersect the other geometry.

Parameters
othergeometry that should not be intersect
Returns
0 in case of success
bool QgsGeometry::moveVertex ( double  x,
double  y,
int  atVertex 
)

Moves the vertex at the given position number and item (first number is index 0) to the given coordinates.

Returns false if atVertex does not correspond to a valid vertex on this geometry

QgsGeometry * QgsGeometry::offsetCurve ( double  distance,
int  segments,
int  joinStyle,
double  mitreLimit 
)

Returns an offset line at a given distance and side from an input line.

See buffer() method for details on parameters.

Note
added in 2.4
needs GEOS >= 3.3 - otherwise always returns 0
QgsGeometry & QgsGeometry::operator= ( QgsGeometry const &  rhs)

assignments will prompt a deep copy of the object

Note
not available in python bindings
bool QgsGeometry::overlaps ( const QgsGeometry geometry) const

Test for if geometry overlaps another (uses GEOS)

Note
added in 1.5
QgsGeometry * QgsGeometry::pointOnSurface ( )

Returns a point within a geometry.

int QgsGeometry::reshapeGeometry ( const QList< QgsPoint > &  reshapeWithLine)

Replaces a part of this geometry with another line.

Returns
0 in case of success
Note
: this function was added in version 1.3
QgsGeometry * QgsGeometry::simplify ( double  tolerance)

Returns a simplified version of this geometry using a specified tolerance value.

int QgsGeometry::splitGeometry ( const QList< QgsPoint > &  splitLine,
QList< QgsGeometry * > &  newGeometries,
bool  topological,
QList< QgsPoint > &  topologyTestPoints 
)

Splits this geometry according to a given line.

Note that the geometry is only split once. If there are several intersections between geometry and splitLine, only the first one is considered.

Parameters
splitLinethe line that splits the geometry
[out]newGeometrieslist of new geometries that have been created with the split
topologicaltrue if topological editing is enabled
[out]topologyTestPointspoints that need to be tested for topological completeness in the dataset
Returns
0 in case of success, 1 if geometry has not been split, error else
double QgsGeometry::sqrDistToVertexAt ( QgsPoint point,
int  atVertex 
)

Returns the squared cartesian distance between the given point to the given vertex index (vertex at the given position number, ring and item (first number is index 0))

QgsGeometry * QgsGeometry::symDifference ( QgsGeometry geometry)

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

bool QgsGeometry::touches ( const QgsGeometry geometry) const

Test for if geometry touch another (uses GEOS)

Note
added in 1.5
int QgsGeometry::transform ( const QgsCoordinateTransform ct)

Transform this geometry as described by CoordinateTranasform ct.

Returns
0 in case of success
int QgsGeometry::translate ( double  dx,
double  dy 
)

Translate this geometry by dx, dy.

Returns
0 in case of success
QGis::GeometryType QgsGeometry::type ( )

Returns type of the vector.

QgsGeometry * QgsGeometry::unaryUnion ( const QList< QgsGeometry * > &  geometryList)
static

compute the unary union on a list of geometries.

May be faster than an iterative union on a set of geometries.

Parameters
geometryLista list of QgsGeometry* as input
Returns
the new computed QgsGeometry, or null
void QgsGeometry::validateGeometry ( QList< Error > &  errors)

Validate geometry and produce a list of geometry errors.

Note
added in 1.5
python binding added in 1.6
QgsPoint QgsGeometry::vertexAt ( int  atVertex)

Returns coordinates of a vertex.

Parameters
atVertexindex of the vertex
Returns
Coordinates of the vertex or QgsPoint(0,0) on error
bool QgsGeometry::within ( const QgsGeometry geometry) const

Test for if geometry is within another (uses GEOS)

Note
added in 1.5
size_t QgsGeometry::wkbSize ( ) const

Returns the size of the WKB in asWkb().

QGis::WkbType QgsGeometry::wkbType ( ) const

Returns type of wkb (point / linestring / polygon etc.)


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