QGIS API Documentation 3.27.0-Master (a46f227e17)
qgsgeometryanglecheck.cpp
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1/***************************************************************************
2 qgsgeometryanglecheck.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
22QList<QgsWkbTypes::GeometryType> QgsGeometryAngleCheck::compatibleGeometryTypes() const
23{
25}
26
27void QgsGeometryAngleCheck::collectErrors( const QMap<QString, QgsFeaturePool *> &featurePools, QList<QgsGeometryCheckError *> &errors, QStringList &messages, QgsFeedback *feedback, const LayerFeatureIds &ids ) const
28{
29 Q_UNUSED( messages )
30 const QMap<QString, QgsFeatureIds> featureIds = ids.isEmpty() ? allLayerFeatureIds( featurePools ) : ids.toMap();
31 const QgsGeometryCheckerUtils::LayerFeatures layerFeatures( featurePools, featureIds, compatibleGeometryTypes(), feedback, context() );
32 for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeature : layerFeatures )
33 {
34 const QgsAbstractGeometry *geom = layerFeature.geometry().constGet();
35 for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
36 {
37 for ( int iRing = 0, nRings = geom->ringCount( iPart ); iRing < nRings; ++iRing )
38 {
39 bool closed = false;
40 const int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, iPart, iRing, &closed );
41 // Less than three points, no angles to check
42 if ( nVerts < 3 )
43 {
44 continue;
45 }
46 for ( int iVert = !closed; iVert < nVerts - !closed; ++iVert )
47 {
48 const QgsPoint &p1 = geom->vertexAt( QgsVertexId( iPart, iRing, ( iVert - 1 + nVerts ) % nVerts ) );
49 const QgsPoint &p2 = geom->vertexAt( QgsVertexId( iPart, iRing, iVert ) );
50 const QgsPoint &p3 = geom->vertexAt( QgsVertexId( iPart, iRing, ( iVert + 1 ) % nVerts ) );
51 QgsVector v21, v23;
52 try
53 {
54 v21 = QgsVector( p1.x() - p2.x(), p1.y() - p2.y() ).normalized();
55 v23 = QgsVector( p3.x() - p2.x(), p3.y() - p2.y() ).normalized();
56 }
57 catch ( const QgsException & )
58 {
59 // Zero length vectors
60 continue;
61 }
62
63 const double angle = std::acos( v21 * v23 ) / M_PI * 180.0;
64 if ( angle < mMinAngle )
65 {
66 errors.append( new QgsGeometryCheckError( this, layerFeature, p2, QgsVertexId( iPart, iRing, iVert ), angle ) );
67 }
68 }
69 }
70 }
71 }
72}
73
74void QgsGeometryAngleCheck::fixError( const QMap<QString, QgsFeaturePool *> &featurePools, QgsGeometryCheckError *error, int method, const QMap<QString, int> & /*mergeAttributeIndices*/, Changes &changes ) const
75{
76 QgsFeaturePool *featurePool = featurePools[ error->layerId() ];
77 QgsFeature feature;
78 if ( !featurePool->getFeature( error->featureId(), feature ) )
79 {
80 error->setObsolete();
81 return;
82 }
83 QgsGeometry featureGeometry = feature.geometry();
84 QgsAbstractGeometry *geometry = featureGeometry.get();
85 const QgsVertexId vidx = error->vidx();
86
87 // Check if point still exists
88 if ( !vidx.isValid( geometry ) )
89 {
90 error->setObsolete();
91 return;
92 }
93
94 // Check if error still applies
95 const int n = QgsGeometryCheckerUtils::polyLineSize( geometry, vidx.part, vidx.ring );
96 if ( n == 0 )
97 {
98 error->setObsolete();
99 return;
100 }
101 const QgsPoint &p1 = geometry->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex - 1 + n ) % n ) );
102 const QgsPoint &p2 = geometry->vertexAt( vidx );
103 const QgsPoint &p3 = geometry->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex + 1 ) % n ) );
104 QgsVector v21, v23;
105 try
106 {
107 v21 = QgsVector( p1.x() - p2.x(), p1.y() - p2.y() ).normalized();
108 v23 = QgsVector( p3.x() - p2.x(), p3.y() - p2.y() ).normalized();
109 }
110 catch ( const QgsException & )
111 {
112 error->setObsolete();
113 return;
114 }
115 const double angle = std::acos( v21 * v23 ) / M_PI * 180.0;
116 if ( angle >= mMinAngle )
117 {
118 error->setObsolete();
119 return;
120 }
121
122 // Fix error
123 if ( method == NoChange )
124 {
125 error->setFixed( method );
126 }
127 else if ( method == DeleteNode )
128 {
129 if ( !QgsGeometryCheckerUtils::canDeleteVertex( geometry, vidx.part, vidx.ring ) )
130 {
131 error->setFixFailed( tr( "Resulting geometry is degenerate" ) );
132 }
133 else if ( !geometry->deleteVertex( error->vidx() ) )
134 {
135 error->setFixFailed( tr( "Failed to delete vertex" ) );
136 }
137 else
138 {
139 changes[error->layerId()][error->featureId()].append( Change( ChangeNode, ChangeRemoved, vidx ) );
140 // Avoid duplicate nodes as result of deleting spike vertex
142 QgsGeometryCheckerUtils::canDeleteVertex( geometry, vidx.part, vidx.ring ) &&
143 geometry->deleteVertex( error->vidx() ) ) // error->vidx points to p3 after removing p2
144 {
145 changes[error->layerId()][error->featureId()].append( Change( ChangeNode, ChangeRemoved, QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex + 1 ) % n ) ) );
146 }
147 feature.setGeometry( featureGeometry );
148 featurePool->updateFeature( feature );
149 error->setFixed( method );
150 }
151 }
152 else
153 {
154 error->setFixFailed( tr( "Unknown method" ) );
155 }
156}
157
159{
160 static const QStringList methods = QStringList() << tr( "Delete node with small angle" ) << tr( "No action" );
161 return methods;
162}
163
165{
166 return factoryId();
167}
168
170{
171 return tr( "Minimal angle" );
172}
173
175{
176 return factoryDescription();
177}
178
180{
181 return factoryCheckType();
182}
183
185{
187}
188
190{
191 return factoryCompatibleGeometryTypes().contains( layer->geometryType() );
192}
193
195{
196 return QStringLiteral( "QgsGeometryAngleCheck" );
197}
198
200{
202}
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.
virtual bool deleteVertex(QgsVertexId position)=0
Deletes a vertex within the geometry.
Defines a QGIS exception class.
Definition: qgsexception.h:35
A feature pool is based on a vector layer and caches features.
virtual void updateFeature(QgsFeature &feature)=0
Updates a feature in this pool.
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
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
Definition: qgsfeature.cpp:170
Base class for feedback objects to be used for cancellation of something running in a worker thread.
Definition: qgsfeedback.h:45
Q_DECL_DEPRECATED QStringList resolutionMethods() const override
Returns a list of descriptions for available resolutions for errors.
static QString factoryDescription()
QgsGeometryCheck::CheckType checkType() const override
Returns the check type.
QString description() const override
Returns a human readable description for this check.
static bool factoryIsCompatible(QgsVectorLayer *layer)
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.
void collectErrors(const QMap< QString, QgsFeaturePool * > &featurePools, QList< QgsGeometryCheckError * > &errors, QStringList &messages, QgsFeedback *feedback, const LayerFeatureIds &ids=LayerFeatureIds()) const override
The main worker method.
QString id() const override
Returns an id for this check.
static QgsGeometryCheck::CheckType factoryCheckType()
QList< QgsWkbTypes::GeometryType > compatibleGeometryTypes() const override
A list of geometry types for which this check can be performed.
static QList< QgsWkbTypes::GeometryType > factoryCompatibleGeometryTypes()
const double tolerance
The tolerance to allow for in geometry checks.
This represents an error reported by a geometry check.
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
@ ChangeNode
This change happens on node level.
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.
@ ChangeRemoved
Something has been removed.
const QgsGeometryCheckContext * context() const
Returns the context.
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 bool canDeleteVertex(const QgsAbstractGeometry *geom, int iPart, int iRing)
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...
static double sqrDistance2D(const QgsPoint &pt1, const QgsPoint &pt2) SIP_HOLDGIL
Returns the squared 2D distance between two points.
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:164
QgsAbstractGeometry * get()
Returns a modifiable (non-const) reference to the underlying abstract geometry primitive.
Point geometry type, with support for z-dimension and m-values.
Definition: qgspoint.h:49
Q_GADGET double x
Definition: qgspoint.h:52
double y
Definition: qgspoint.h:53
Represents a vector layer which manages a vector based data sets.
Q_INVOKABLE QgsWkbTypes::GeometryType geometryType() const
Returns point, line or polygon.
A class to represent a vector.
Definition: qgsvector.h:30
QgsVector normalized() const SIP_THROW(QgsException)
Returns the vector's normalized (or "unit") vector (ie same angle but length of 1....
Definition: qgsvector.cpp:28
double ANALYSIS_EXPORT angle(QgsPoint *p1, QgsPoint *p2, QgsPoint *p3, QgsPoint *p4)
Calculates the angle between two segments (in 2 dimension, z-values are ignored)
Definition: MathUtils.cpp:786
Descripts a change to fix a geometry.
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