[needs-docs][processing] Add option to check validity alg to ignore s…

…elf-intersection causing rings errors By default the algorithm now uses the strict OGC definition of polygon validity, where a polygon is marked as invalid if a self-intersecting ring causes an interior hole. If the "Ignore ring self intersections" option is checked, then this rule will be ignored and a more lenient validity check will be performed. Refs #16418, refs #21336 (cherry picked from commit 49742c3)
qgis · Mar 5, 2019 · 850905e · 850905e
1 parent 25a42a9
commit 850905e
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Showing 9 changed files with 152 additions and 4 deletions.
diff --git a/python/plugins/processing/algs/help/qgis.yaml b/python/plugins/processing/algs/help/qgis.yaml
@@ -51,6 +51,8 @@ qgis:checkvalidity: >
 
   The geometries are classified in three groups (valid, invalid and error), and a vector layer is generated with the features in each of these categories.
 
+  By default the algorithm uses the strict OGC definition of polygon validity, where a polygon is marked as invalid if a self-intersecting ring causes an interior hole. If the "Ignore ring self intersections" option is checked, then this rule will be ignored and a more lenient validity check will be performed.
+
 qgis:clip: >
   This algorithm clips a vector layer using the polygons of an additional polygons layer. Only the parts of the features in the input layer that falls within the polygons of the clipping layer will be added to the resulting layer.
 

diff --git a/python/plugins/processing/algs/qgis/CheckValidity.py b/python/plugins/processing/algs/qgis/CheckValidity.py
@@ -45,7 +45,8 @@
                        QgsProcessingParameterFeatureSource,
                        QgsProcessingParameterEnum,
                        QgsProcessingParameterFeatureSink,
-                       QgsProcessingOutputNumber)
+                       QgsProcessingOutputNumber,
+                       QgsProcessingParameterBoolean)
 from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
 
 settings_method_key = "/qgis/digitizing/validate_geometries"
@@ -62,6 +63,7 @@ class CheckValidity(QgisAlgorithm):
     INVALID_COUNT = 'INVALID_COUNT'
     ERROR_OUTPUT = 'ERROR_OUTPUT'
     ERROR_COUNT = 'ERROR_COUNT'
+    IGNORE_RING_SELF_INTERSECTION = 'IGNORE_RING_SELF_INTERSECTION'
 
     def icon(self):
         return QgsApplication.getThemeIcon("/algorithms/mAlgorithmCheckGeometry.svg")
@@ -96,6 +98,9 @@ def initAlgorithm(self, config=None):
                 'useCheckBoxes': True,
                 'columns': 3}})
 
+        self.addParameter(QgsProcessingParameterBoolean(self.IGNORE_RING_SELF_INTERSECTION,
+                                                        self.tr('Ignore ring self intersections'), defaultValue=False))
+
         self.addParameter(QgsProcessingParameterFeatureSink(self.VALID_OUTPUT, self.tr('Valid output'), QgsProcessing.TypeVectorAnyGeometry, '', True))
         self.addOutput(QgsProcessingOutputNumber(self.VALID_COUNT, self.tr('Count of valid features')))
 
@@ -112,6 +117,7 @@ def displayName(self):
         return self.tr('Check validity')
 
     def processAlgorithm(self, parameters, context, feedback):
+        ignore_ring_self_intersection = self.parameterAsBool(parameters, self.IGNORE_RING_SELF_INTERSECTION, context)
         method_param = self.parameterAsEnum(parameters, self.METHOD, context)
         if method_param == 0:
             settings = QgsSettings()
@@ -121,10 +127,11 @@ def processAlgorithm(self, parameters, context, feedback):
         else:
             method = method_param - 1
 
-        results = self.doCheck(method, parameters, context, feedback)
+        results = self.doCheck(method, parameters, context, feedback, ignore_ring_self_intersection)
         return results
 
-    def doCheck(self, method, parameters, context, feedback):
+    def doCheck(self, method, parameters, context, feedback, ignore_ring_self_intersection):
+        flags = QgsGeometry.FlagAllowSelfTouchingHoles if ignore_ring_self_intersection else QgsGeometry.ValidityFlags()
         source = self.parameterAsSource(parameters, self.INPUT_LAYER, context)
         if source is None:
             raise QgsProcessingException(self.invalidSourceError(parameters, self.INPUT_LAYER))
@@ -155,7 +162,7 @@ def doCheck(self, method, parameters, context, feedback):
 
             valid = True
             if not geom.isNull() and not geom.isEmpty():
-                errors = list(geom.validateGeometry(method))
+                errors = list(geom.validateGeometry(method, flags))
                 if errors:
                     valid = False
                     reasons = []

diff --git a/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_error_ignore_self.gml b/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_error_ignore_self.gml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ poly_ring_self_intersection_error_ignore_self.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy><gml:null>missing</gml:null></gml:boundedBy>
+
+</ogr:FeatureCollection>
diff --git a/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_error_ignore_self.xsd b/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_error_ignore_self.xsd
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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">
+<xs:import namespace="http://www.opengis.net/gml" schemaLocation="http://schemas.opengis.net/gml/2.1.2/feature.xsd"/>
+<xs:element name="FeatureCollection" type="ogr:FeatureCollectionType" substitutionGroup="gml:_FeatureCollection"/>
+<xs:complexType name="FeatureCollectionType">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureCollectionType">
+      <xs:attribute name="lockId" type="xs:string" use="optional"/>
+      <xs:attribute name="scope" type="xs:string" use="optional"/>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+<xs:element name="poly_ring_self_intersection_error_ignore_self" type="ogr:poly_ring_self_intersection_error_ignore_self_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="poly_ring_self_intersection_error_ignore_self_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:PointPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+        <xs:element name="message" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:string">
+              <xs:maxLength value="255"/>
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
diff --git a/...ns/processing/tests/testdata/expected/poly_ring_self_intersection_invalid_ignore_self.gml b/...ns/processing/tests/testdata/expected/poly_ring_self_intersection_invalid_ignore_self.gml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ poly_ring_self_intersection_invalid_ignore_self.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy><gml:null>missing</gml:null></gml:boundedBy>
+
+</ogr:FeatureCollection>
diff --git a/...ns/processing/tests/testdata/expected/poly_ring_self_intersection_invalid_ignore_self.xsd b/...ns/processing/tests/testdata/expected/poly_ring_self_intersection_invalid_ignore_self.xsd
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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">
+<xs:import namespace="http://www.opengis.net/gml" schemaLocation="http://schemas.opengis.net/gml/2.1.2/feature.xsd"/>
+<xs:element name="FeatureCollection" type="ogr:FeatureCollectionType" substitutionGroup="gml:_FeatureCollection"/>
+<xs:complexType name="FeatureCollectionType">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureCollectionType">
+      <xs:attribute name="lockId" type="xs:string" use="optional"/>
+      <xs:attribute name="scope" type="xs:string" use="optional"/>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+<xs:element name="poly_ring_self_intersection_invalid_ignore_self" type="ogr:poly_ring_self_intersection_invalid_ignore_self_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="poly_ring_self_intersection_invalid_ignore_self_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:PolygonPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+        <xs:element name="_errors" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:string">
+              <xs:maxLength value="255"/>
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
diff --git a/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_valid_ignore_self.gml b/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_valid_ignore_self.gml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ poly_ring_self_intersection_valid_ignore_self.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>200</gml:X><gml:Y>200</gml:Y></gml:coord>
+      <gml:coord><gml:X>400</gml:X><gml:Y>400</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+
+  <gml:featureMember>
+    <ogr:poly_ring_self_intersection_valid_ignore_self fid="poly_ring_self_intersection.0">
+      <ogr:geometryProperty><gml:Polygon srsName="EPSG:28356"><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>200,400 400,400 400,200 300,200 350,250 250,250 300,200 200,200 200,400</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></ogr:geometryProperty>
+    </ogr:poly_ring_self_intersection_valid_ignore_self>
+  </gml:featureMember>
+</ogr:FeatureCollection>
diff --git a/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_valid_ignore_self.xsd b/...gins/processing/tests/testdata/expected/poly_ring_self_intersection_valid_ignore_self.xsd
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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">
+<xs:import namespace="http://www.opengis.net/gml" schemaLocation="http://schemas.opengis.net/gml/2.1.2/feature.xsd"/>
+<xs:element name="FeatureCollection" type="ogr:FeatureCollectionType" substitutionGroup="gml:_FeatureCollection"/>
+<xs:complexType name="FeatureCollectionType">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureCollectionType">
+      <xs:attribute name="lockId" type="xs:string" use="optional"/>
+      <xs:attribute name="scope" type="xs:string" use="optional"/>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+<xs:element name="poly_ring_self_intersection_valid_ignore_self" type="ogr:poly_ring_self_intersection_valid_ignore_self_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="poly_ring_self_intersection_valid_ignore_self_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:PolygonPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
diff --git a/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml b/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml
@@ -3764,6 +3764,25 @@ tests:
         name: expected/poly_ring_self_intersection_valid.gml
         type: vector
 
+  - algorithm: qgis:checkvalidity
+    name: Check validity polygon ring self intersection, ignoring self intersections
+    params:
+      IGNORE_RING_SELF_INTERSECTION: true
+      INPUT_LAYER:
+        name: custom/poly_ring_self_intersection.gml|layername=poly_ring_self_intersection
+        type: vector
+      METHOD: 2
+    results:
+      ERROR_OUTPUT:
+        name: expected/poly_ring_self_intersection_error_ignore_self.gml
+        type: vector
+      INVALID_OUTPUT:
+        name: expected/poly_ring_self_intersection_invalid_ignore_self.gml
+        type: vector
+      VALID_OUTPUT:
+        name: expected/poly_ring_self_intersection_valid_ignore_self.gml
+        type: vector
+
   - algorithm: qgis:polygonize
     name: Polygonize
     params: