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Add API method to remove duplicate nodes from geometries
Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a degenerate geometry. By default, z values are not considered when detecting duplicate nodes. E.g. two nodes with the same x and y coordinate but different z values will still be considered duplicate and one will be removed. If useZValues is true, then the z values are also tested and nodes with the same x and y but different z will be maintained. Note that duplicate nodes are not tested between different parts of a multipart geometry. E.g. a multipoint geometry with overlapping points will not be changed by this method. The function will return true if nodes were removed, or false if no duplicate nodes were found. Includes unit tests and a processing algorithm which exposes this functionality.
1 parent 0b452ca commit e12621c

34 files changed

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‎python/core/geometry/qgsabstractgeometry.sip‎

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@@ -436,6 +436,29 @@ Returns the centroid of the geometry
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:rtype: QgsAbstractGeometry
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%End
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false ) = 0;
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%Docstring
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Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a
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degenerate geometry.
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The ``epsilon`` parameter specifies the tolerance for coordinates when determining that
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vertices are identical.
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By default, z values are not considered when detecting duplicate nodes. E.g. two nodes
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with the same x and y coordinate but different z values will still be considered
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duplicate and one will be removed. If ``useZValues`` is true, then the z values are
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also tested and nodes with the same x and y but different z will be maintained.
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Note that duplicate nodes are not tested between different parts of a multipart geometry. E.g.
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a multipoint geometry with overlapping points will not be changed by this method.
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The function will return true if nodes were removed, or false if no duplicate nodes
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were found.
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.. versionadded:: 3.0
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:rtype: bool
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%End
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virtual double vertexAngle( QgsVertexId vertex ) const = 0;
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%Docstring
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Returns approximate angle at a vertex. This is usually the average angle between adjacent

‎python/core/geometry/qgscircularstring.sip‎

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@@ -83,6 +83,9 @@ class QgsCircularString: QgsCurve
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virtual QgsCircularString *snappedToGrid( double hSpacing, double vSpacing, double dSpacing = 0, double mSpacing = 0 ) const /Factory/;
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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virtual void draw( QPainter &p ) const;
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virtual void transform( const QgsCoordinateTransform &ct, QgsCoordinateTransform::TransformDirection d = QgsCoordinateTransform::ForwardTransform,

‎python/core/geometry/qgscompoundcurve.sip‎

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@@ -79,6 +79,8 @@ class QgsCompoundCurve: QgsCurve
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virtual QgsCompoundCurve *snappedToGrid( double hSpacing, double vSpacing, double dSpacing = 0, double mSpacing = 0 ) const /Factory/;
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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int nCurves() const;
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%Docstring

‎python/core/geometry/qgscurvepolygon.sip‎

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virtual QgsCurvePolygon *snappedToGrid( double hSpacing, double vSpacing, double dSpacing = 0, double mSpacing = 0 ) const /Factory/;
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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int numInteriorRings() const;
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%Docstring

‎python/core/geometry/qgsgeometry.sip‎

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@@ -688,6 +688,29 @@ Returns true if WKB of the geometry is of WKBMulti* type
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:rtype: QgsGeometry
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%End
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bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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%Docstring
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Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a
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degenerate geometry.
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The ``epsilon`` parameter specifies the tolerance for coordinates when determining that
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vertices are identical.
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By default, z values are not considered when detecting duplicate nodes. E.g. two nodes
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with the same x and y coordinate but different z values will still be considered
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duplicate and one will be removed. If ``useZValues`` is true, then the z values are
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also tested and nodes with the same x and y but different z will be maintained.
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Note that duplicate nodes are not tested between different parts of a multipart geometry. E.g.
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a multipoint geometry with overlapping points will not be changed by this method.
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The function will return true if nodes were removed, or false if no duplicate nodes
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were found.
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.. versionadded:: 3.0
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:rtype: bool
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%End
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bool intersects( const QgsRectangle &r ) const;
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%Docstring
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Tests for intersection with a rectangle (uses GEOS)

‎python/core/geometry/qgsgeometrycollection.sip‎

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virtual void clear();
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virtual QgsGeometryCollection *snappedToGrid( double hSpacing, double vSpacing, double dSpacing = 0, double mSpacing = 0 ) const /Factory/;
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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virtual QgsAbstractGeometry *boundary() const /Factory/;
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virtual void adjacentVertices( QgsVertexId vertex, QgsVertexId &previousVertex /Out/, QgsVertexId &nextVertex /Out/ ) const;

‎python/core/geometry/qgslinestring.sip‎

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@@ -179,6 +179,8 @@ Closes the line string by appending the first point to the end of the line, if i
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virtual QgsLineString *snappedToGrid( double hSpacing, double vSpacing, double dSpacing = 0, double mSpacing = 0 ) const /Factory/;
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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virtual bool fromWkb( QgsConstWkbPtr &wkb );
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‎python/core/geometry/qgspoint.sip‎

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virtual QgsPoint *clone() const /Factory/;
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virtual QgsPoint *snappedToGrid( double hSpacing, double vSpacing, double dSpacing = 0, double mSpacing = 0 ) const /Factory/;
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virtual bool removeDuplicateNodes( double epsilon = 4 * DBL_EPSILON, bool useZValues = false );
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virtual void clear();
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virtual bool fromWkb( QgsConstWkbPtr &wkb );

‎python/plugins/processing/tests/testdata/custom/line_duplicate_nodes.gml‎

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<?xml version="1.0" encoding="utf-8" ?>
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<ogr:FeatureCollection
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xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xsi:schemaLocation="http://ogr.maptools.org/ line_duplicate_nodes.xsd"
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xmlns:ogr="http://ogr.maptools.org/"
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xmlns:gml="http://www.opengis.net/gml">
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<gml:boundedBy>
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<gml:Box>
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<gml:coord><gml:X>2</gml:X><gml:Y>0</gml:Y></gml:coord>
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<gml:coord><gml:X>3</gml:X><gml:Y>3</gml:Y></gml:coord>
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</gml:Box>
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</gml:boundedBy>
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<gml:featureMember>
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<ogr:line_duplicate_nodes fid="lines.2">
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<ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>2,0 2,2 3,2 3,3 3,3</gml:coordinates></gml:LineString></ogr:geometryProperty>
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</ogr:line_duplicate_nodes>
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</gml:featureMember>
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</ogr:FeatureCollection>

‎python/plugins/processing/tests/testdata/custom/line_duplicate_nodes.xsd‎

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<?xml version="1.0" encoding="UTF-8"?>
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<xs:schema targetNamespace="http://ogr.maptools.org/" xmlns:ogr="http://ogr.maptools.org/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:gml="http://www.opengis.net/gml" elementFormDefault="qualified" version="1.0">
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<xs:import namespace="http://www.opengis.net/gml" schemaLocation="http://schemas.opengis.net/gml/2.1.2/feature.xsd"/>
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<xs:element name="FeatureCollection" type="ogr:FeatureCollectionType" substitutionGroup="gml:_FeatureCollection"/>
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<xs:complexType name="FeatureCollectionType">
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<xs:complexContent>
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<xs:extension base="gml:AbstractFeatureCollectionType">
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<xs:attribute name="lockId" type="xs:string" use="optional"/>
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<xs:attribute name="scope" type="xs:string" use="optional"/>
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</xs:extension>
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</xs:complexContent>
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</xs:complexType>
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<xs:element name="line_duplicate_nodes" type="ogr:line_duplicate_nodes_Type" substitutionGroup="gml:_Feature"/>
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<xs:complexType name="line_duplicate_nodes_Type">
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<xs:complexContent>
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<xs:extension base="gml:AbstractFeatureType">
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<xs:sequence>
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<xs:element name="geometryProperty" type="gml:LineStringPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
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</xs:sequence>
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</xs:extension>
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</xs:complexContent>
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</xs:complexType>
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</xs:schema>

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