QGIS API Documentation  3.23.0-Master (c716e02dd3)
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 
17 #include "qgsgeometryanglecheck.h"
18 #include "qgsgeometryutils.h"
19 #include "qgsfeaturepool.h"
20 #include "qgsgeometrycheckerror.h"
21 
22 QList<QgsWkbTypes::GeometryType> QgsGeometryAngleCheck::compatibleGeometryTypes() const
23 {
25 }
26 
27 void 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 
74 void 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:163
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 QString & layerId() const
The id of the layer on which this error has been detected.
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.
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:125
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