QGIS API Documentation 3.27.0-Master (9c08adf5ef)
qgsgeometrysegmentlengthcheck.cpp
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1/***************************************************************************
2 qgsgeometrysegmentlengthcheck.cpp
3 ---------------------
4 begin : September 2015
5 copyright : (C) 2014 by Sandro Mani / Sourcepole AG
6 email : smani at sourcepole dot ch
7 ***************************************************************************
8 * *
9 * This program is free software; you can redistribute it and/or modify *
10 * it under the terms of the GNU General Public License as published by *
11 * the Free Software Foundation; either version 2 of the License, or *
12 * (at your option) any later version. *
13 * *
14 ***************************************************************************/
15
18#include "qgsgeometryutils.h"
19#include "qgsfeaturepool.h"
21
22void QgsGeometrySegmentLengthCheck::collectErrors( const QMap<QString, QgsFeaturePool *> &featurePools, QList<QgsGeometryCheckError *> &errors, QStringList &messages, QgsFeedback *feedback, const LayerFeatureIds &ids ) const
23{
24 Q_UNUSED( messages )
25
26 const QMap<QString, QgsFeatureIds> featureIds = ids.isEmpty() ? allLayerFeatureIds( featurePools ) : ids.toMap();
27 const QgsGeometryCheckerUtils::LayerFeatures layerFeatures( featurePools, featureIds, compatibleGeometryTypes(), feedback, mContext );
28 for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeature : layerFeatures )
29 {
30 const double layerToMapUnits = scaleFactor( layerFeature.layer() );
31 const double minLength = mMinLengthMapUnits / layerToMapUnits;
32
33 const QgsAbstractGeometry *geom = layerFeature.geometry().constGet();
34 for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
35 {
36 for ( int iRing = 0, nRings = geom->ringCount( iPart ); iRing < nRings; ++iRing )
37 {
38 bool isClosed = false;
39 const int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, iPart, iRing, &isClosed );
40 if ( nVerts < 2 )
41 {
42 continue;
43 }
44 for ( int iVert = isClosed ? 0 : 1, jVert = isClosed ? nVerts - 1 : 0; iVert < nVerts; jVert = iVert++ )
45 {
46 const QgsPoint pi = geom->vertexAt( QgsVertexId( iPart, iRing, iVert ) );
47 const QgsPoint pj = geom->vertexAt( QgsVertexId( iPart, iRing, jVert ) );
48 const double dist = pi.distance( pj );
49 // Don't report very small lengths, they are either duplicate nodes or degenerate geometries
50 if ( dist < minLength && dist > mContext->tolerance )
51 {
52 const QgsPointXY pos( 0.5 * ( pi.x() + pj.x() ), 0.5 * ( pi.y() + pj.y() ) );
53 errors.append( new QgsGeometryCheckError( this, layerFeature, pos, QgsVertexId( iPart, iRing, iVert ), dist * layerToMapUnits, QgsGeometryCheckError::ValueLength ) );
54 }
55 }
56 }
57 }
58 }
59}
60
61void QgsGeometrySegmentLengthCheck::fixError( const QMap<QString, QgsFeaturePool *> &featurePools, QgsGeometryCheckError *error, int method, const QMap<QString, int> & /*mergeAttributeIndices*/, Changes &/*changes*/ ) const
62{
63 QgsFeaturePool *featurePool = featurePools[ error->layerId() ];
64 QgsFeature feature;
65 if ( !featurePool->getFeature( error->featureId(), feature ) )
66 {
67 error->setObsolete();
68 return;
69 }
70
71 const QgsGeometry featureGeom = feature.geometry();
72 const QgsAbstractGeometry *geom = featureGeom.constGet();
73 const QgsVertexId vidx = error->vidx();
74
75 // Check if point still exists
76 if ( !vidx.isValid( geom ) )
77 {
78 error->setObsolete();
79 return;
80 }
81
82 // Check if error still applies
83 const int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, vidx.part, vidx.ring );
84 if ( nVerts == 0 )
85 {
86 error->setObsolete();
87 return;
88 }
89
90 const QgsPoint pi = geom->vertexAt( error->vidx() );
91 const QgsPoint pj = geom->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex - 1 + nVerts ) % nVerts ) );
92 const double dist = pi.distance( pj );
93 const double layerToMapUnits = scaleFactor( featurePool->layer() );
94 const double minLength = mMinLengthMapUnits / layerToMapUnits;
95 if ( dist >= minLength )
96 {
97 error->setObsolete();
98 return;
99 }
100
101 // Fix error
102 if ( method == NoChange )
103 {
104 error->setFixed( method );
105 }
106 else
107 {
108 error->setFixFailed( tr( "Unknown method" ) );
109 }
110}
111
113{
114 static const QStringList methods = QStringList() << tr( "No action" );
115 return methods;
116}
117
119{
121}
Abstract base class for all geometries.
virtual int ringCount(int part=0) const =0
Returns the number of rings of which this geometry is built.
virtual QgsPoint vertexAt(QgsVertexId id) const =0
Returns the point corresponding to a specified vertex id.
virtual int partCount() const =0
Returns count of parts contained in the geometry.
A feature pool is based on a vector layer and caches features.
QgsVectorLayer * layer() const
Gets a pointer to the underlying layer.
bool getFeature(QgsFeatureId id, QgsFeature &feature)
Retrieves the feature with the specified id into feature.
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
QgsGeometry geometry
Definition: qgsfeature.h:67
Base class for feedback objects to be used for cancellation of something running in a worker thread.
Definition: qgsfeedback.h:45
const double tolerance
The tolerance to allow for in geometry checks.
This represents an error reported by a geometry check.
@ ValueLength
The value is a length.
const QgsVertexId & vidx() const
The id of the affected vertex.
QgsFeatureId featureId() const
The id of the feature on which this error has been detected.
void setFixed(int method)
Set the status to fixed and specify the method that has been used to fix the error.
void setFixFailed(const QString &reason)
Set the error status to failed and specify the reason for failure.
void setObsolete()
Set the error status to obsolete.
const QString & layerId() const
The id of the layer on which this error has been detected.
QMap< QString, QMap< QgsFeatureId, QList< QgsGeometryCheck::Change > > > Changes
A collection of changes.
const QgsGeometryCheckContext * mContext
CheckType
The type of a check.
@ FeatureNodeCheck
The check controls individual nodes.
QMap< QString, QgsFeatureIds > allLayerFeatureIds(const QMap< QString, QgsFeaturePool * > &featurePools) const
Returns all layers and feature ids.
double scaleFactor(const QPointer< QgsVectorLayer > &layer) const
Determines the scale factor of a layer to the map coordinate reference system.
A layer feature combination to uniquely identify and access a feature in a set of layers.
Contains a set of layers and feature ids in those layers to pass to a geometry check.
static int polyLineSize(const QgsAbstractGeometry *geom, int iPart, int iRing, bool *isClosed=nullptr)
Returns the number of points in a polyline, accounting for duplicate start and end point if the polyl...
QList< QgsWkbTypes::GeometryType > compatibleGeometryTypes() const override
A list of geometry types for which this check can be performed.
static QgsGeometryCheck::CheckType factoryCheckType()
Q_DECL_DEPRECATED QStringList resolutionMethods() const override
Returns a list of descriptions for available resolutions for errors.
void collectErrors(const QMap< QString, QgsFeaturePool * > &featurePools, QList< QgsGeometryCheckError * > &errors, QStringList &messages, QgsFeedback *feedback, const LayerFeatureIds &ids=LayerFeatureIds()) const override
The main worker method.
void fixError(const QMap< QString, QgsFeaturePool * > &featurePools, QgsGeometryCheckError *error, int method, const QMap< QString, int > &mergeAttributeIndices, Changes &changes) const override
Fixes the error error with the specified method.
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:125
const QgsAbstractGeometry * constGet() const SIP_HOLDGIL
Returns a non-modifiable (const) reference to the underlying abstract geometry primitive.
A class to represent a 2D point.
Definition: qgspointxy.h:59
Point geometry type, with support for z-dimension and m-values.
Definition: qgspoint.h:49
double distance(double x, double y) const SIP_HOLDGIL
Returns the Cartesian 2D distance between this point and a specified x, y coordinate.
Definition: qgspoint.h:343
Q_GADGET double x
Definition: qgspoint.h:52
double y
Definition: qgspoint.h:53
A list of layers and feature ids for each of these layers.
QMap< QString, QgsFeatureIds > toMap() const
Utility class for identifying a unique vertex within a geometry.
Definition: qgsvertexid.h:31
int vertex
Vertex number.
Definition: qgsvertexid.h:95
int part
Part number.
Definition: qgsvertexid.h:89
int ring
Ring number.
Definition: qgsvertexid.h:92
bool isValid() const SIP_HOLDGIL
Returns true if the vertex id is valid.
Definition: qgsvertexid.h:46