[FEATURE][processing] New algorithm for geometry boundary

2025-04-13 00:03:09 -04:00 · 2016-08-10 16:32:31 +10:00 · 2016-08-10 16:32:31 +10:00 · ab022451a5
commit ab022451a5
parent 9e66e1593b
12 changed files with 458 additions and 1 deletions
--- a/python/plugins/processing/algs/help/qgis.yaml
+++ b/python/plugins/processing/algs/help/qgis.yaml
@ -33,6 +33,9 @@ qgis:basicstatisticsfortextfields: >

  Statistics are generated as an HTML file.

+qgis:boundary: >
+  Returns the closure of the combinatorial boundary of the input geometries (ie the topological boundary of the geometry). For instance, a polygon geometry will have a boundary consisting of the linestrings for each ring in the polygon. Only valid for polygon or line layers.
+
 qgis:boundingboxes: >
  This algorithm calculates the bounding box (envelope) of each feature in an input layer.

--- a/python/plugins/processing/algs/qgis/Boundary.py
+++ b/python/plugins/processing/algs/qgis/Boundary.py
@ -0,0 +1,97 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    Boundary.py
+    --------------
+    Date                 : July 2016
+    Copyright            : (C) 2016 by Nyall Dawson
+    Email                : nyall dot dawson at gmail dot com
+***************************************************************************
+*                                                                         *
+*   This program is free software; you can redistribute it and/or modify  *
+*   it under the terms of the GNU General Public License as published by  *
+*   the Free Software Foundation; either version 2 of the License, or     *
+*   (at your option) any later version.                                   *
+*                                                                         *
+***************************************************************************
+"""
+
+__author__ = 'Nyall Dawson'
+__date__ = 'July 2016'
+__copyright__ = '(C) 2016, Nyall Dawson'
+
+# This will get replaced with a git SHA1 when you do a git archive323
+
+__revision__ = '$Format:%H$'
+
+import os
+
+from qgis.core import QgsGeometry, QgsWkbTypes
+
+from qgis.PyQt.QtGui import QIcon
+
+from processing.core.GeoAlgorithm import GeoAlgorithm
+from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
+from processing.core.parameters import ParameterVector
+from processing.core.outputs import OutputVector
+from processing.tools import dataobjects, vector
+
+pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
+
+
+class Boundary(GeoAlgorithm):
+
+    INPUT_LAYER = 'INPUT_LAYER'
+    OUTPUT_LAYER = 'OUTPUT_LAYER'
+
+    def getIcon(self):
+        return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'convex_hull.png'))
+
+    def defineCharacteristics(self):
+        self.name, self.i18n_name = self.trAlgorithm('Boundary')
+        self.group, self.i18n_group = self.trAlgorithm('Vector geometry tools')
+
+        self.addParameter(ParameterVector(self.INPUT_LAYER,
+                                          self.tr('Input layer'), [ParameterVector.VECTOR_TYPE_LINE,
+                                                                   ParameterVector.VECTOR_TYPE_POLYGON]))
+        self.addOutput(OutputVector(self.OUTPUT_LAYER, self.tr('Boundary')))
+
+    def processAlgorithm(self, progress):
+        layer = dataobjects.getObjectFromUri(
+            self.getParameterValue(self.INPUT_LAYER))
+
+        input_wkb = layer.wkbType()
+        if QgsWkbTypes.geometryType(input_wkb) == QgsWkbTypes.LineGeometry:
+            output_wkb = QgsWkbTypes.MultiPoint
+        elif QgsWkbTypes.geometryType(input_wkb) == QgsWkbTypes.PolygonGeometry:
+            output_wkb = QgsWkbTypes.MultiLineString
+        if QgsWkbTypes.hasZ(input_wkb):
+            output_wkb = QgsWkbTypes.addZ(output_wkb)
+        if QgsWkbTypes.hasM(input_wkb):
+            output_wkb = QgsWkbTypes.addM(output_wkb)
+
+        writer = self.getOutputFromName(
+            self.OUTPUT_LAYER).getVectorWriter(
+                layer.fields(),
+                output_wkb,
+                layer.crs())
+
+        features = vector.features(layer)
+        total = 100.0 / len(features)
+
+        for current, input_feature in enumerate(features):
+            output_feature = input_feature
+            input_geometry = input_feature.geometry()
+            if input_geometry:
+                output_geometry = QgsGeometry(input_geometry.geometry().boundary())
+                if not output_geometry:
+                    raise GeoAlgorithmExecutionException(
+                        self.tr('Error calculating boundary'))
+
+                output_feature.setGeometry(output_geometry)
+
+            writer.addFeature(output_feature)
+            progress.setPercentage(int(current * total))
+
+        del writer
--- a/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
+++ b/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
@ -148,6 +148,7 @@ from .RectanglesOvalsDiamondsVariable import RectanglesOvalsDiamondsVariable
 from .RectanglesOvalsDiamondsFixed import RectanglesOvalsDiamondsFixed
 from .MergeLines import MergeLines
 from .BoundingBox import BoundingBox
+from .Boundary import Boundary

 pluginPath = os.path.normpath(os.path.join(
    os.path.split(os.path.dirname(__file__))[0], os.pardir))
@ -200,7 +201,7 @@ class QGISAlgorithmProvider(AlgorithmProvider):
                        ReverseLineDirection(), SpatialIndex(), DefineProjection(),
                        RectanglesOvalsDiamondsVariable(),
                        RectanglesOvalsDiamondsFixed(), MergeLines(),
-                        BoundingBox()
+                        BoundingBox(), Boundary()
                        ]

        if hasMatplotlib:
--- a/python/plugins/processing/tests/testdata/expected/lines_boundary.gml
+++ b/python/plugins/processing/tests/testdata/expected/lines_boundary.gml
@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ lines_boundary.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>-1</gml:X><gml:Y>-3</gml:Y></gml:coord>
+      <gml:coord><gml:X>11</gml:X><gml:Y>5</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                                                             
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.0">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>6,2</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>11,5</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:lines_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.1">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>-1,-1</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>1,-1</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:lines_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.2">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>2,0</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>3,3</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:lines_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.3">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>3,1</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>5,1</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:lines_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.4">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>7,-3</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>10,-3</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:lines_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.5">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>6,-3</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>10,1</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:lines_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:lines_boundary fid="lines.6">
+    </ogr:lines_boundary>
+  </gml:featureMember>
+</ogr:FeatureCollection>
--- a/python/plugins/processing/tests/testdata/expected/lines_boundary.xsd
+++ b/python/plugins/processing/tests/testdata/expected/lines_boundary.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="lines_boundary" type="ogr:lines_boundary_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="lines_boundary_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:MultiPointPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
--- a/python/plugins/processing/tests/testdata/expected/multiline_boundary.gml
+++ b/python/plugins/processing/tests/testdata/expected/multiline_boundary.gml
@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ multiline_boundary.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>-1</gml:X><gml:Y>-1</gml:Y></gml:coord>
+      <gml:coord><gml:X>5.58042226487524</gml:X><gml:Y>4.119769673704415</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                               
+  <gml:featureMember>
+    <ogr:multiline_boundary fid="lines.1">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>-1,-1</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>1,-1</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:multiline_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:multiline_boundary fid="lines.2">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>3,1</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>5,1</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>5.024184261036468,2.414779270633399</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>5,1</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:multiline_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:multiline_boundary fid="lines.3">
+    </ogr:multiline_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:multiline_boundary fid="lines.4">
+      <ogr:geometryProperty><gml:MultiPoint srsName="EPSG:4326"><gml:pointMember><gml:Point><gml:coordinates>2,0</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>3,3</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>2.944337811900192,4.04721689059501</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>5.459500959692898,4.119769673704415</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>3,3</gml:coordinates></gml:Point></gml:pointMember><gml:pointMember><gml:Point><gml:coordinates>5.58042226487524,2.946833013435702</gml:coordinates></gml:Point></gml:pointMember></gml:MultiPoint></ogr:geometryProperty>
+    </ogr:multiline_boundary>
+  </gml:featureMember>
+</ogr:FeatureCollection>
--- a/python/plugins/processing/tests/testdata/expected/multiline_boundary.xsd
+++ b/python/plugins/processing/tests/testdata/expected/multiline_boundary.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="multiline_boundary" type="ogr:multiline_boundary_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="multiline_boundary_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:MultiPointPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
--- a/python/plugins/processing/tests/testdata/expected/multipoly_boundary.gml
+++ b/python/plugins/processing/tests/testdata/expected/multipoly_boundary.gml
@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ multipoly_boundary.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>0</gml:X><gml:Y>-1</gml:Y></gml:coord>
+      <gml:coord><gml:X>9</gml:X><gml:Y>6</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                                                               
+  <gml:featureMember>
+    <ogr:multipoly_boundary fid="multipolys.0">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>2,1 2,2 3,2 3,3 4,3 4,1 2,1</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:Bname>Test</ogr:Bname>
+      <ogr:Bintval>1</ogr:Bintval>
+      <ogr:Bfloatval>0.123</ogr:Bfloatval>
+    </ogr:multipoly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:multipoly_boundary fid="multipolys.1">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>7,-1 8,-1 8,3 7,3 7,-1</gml:coordinates></gml:LineString></gml:lineStringMember><gml:lineStringMember><gml:LineString><gml:coordinates>7,6 7,5 7,4 8,4 9,5 9,6 7,6</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+    </ogr:multipoly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:multipoly_boundary fid="multipolys.2">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>0,0 0,1 1,1 1,0 0,0</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:Bname>Test</ogr:Bname>
+      <ogr:Bintval>2</ogr:Bintval>
+      <ogr:Bfloatval>-0.123</ogr:Bfloatval>
+    </ogr:multipoly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:multipoly_boundary fid="multipolys.3">
+      <ogr:Bname>Test</ogr:Bname>
+      <ogr:Bintval>3</ogr:Bintval>
+      <ogr:Bfloatval>0</ogr:Bfloatval>
+    </ogr:multipoly_boundary>
+  </gml:featureMember>
+</ogr:FeatureCollection>
--- a/python/plugins/processing/tests/testdata/expected/multipoly_boundary.xsd
+++ b/python/plugins/processing/tests/testdata/expected/multipoly_boundary.xsd
@ -0,0 +1,43 @@
+<?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="multipoly_boundary" type="ogr:multipoly_boundary_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="multipoly_boundary_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:MultiLineStringPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+        <xs:element name="Bname" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:string">
+              <xs:maxLength value="4"/>
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+        <xs:element name="Bintval" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:integer">
+              <xs:totalDigits value="16"/>
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+        <xs:element name="Bfloatval" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:decimal">
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
--- a/python/plugins/processing/tests/testdata/expected/poly_boundary.gml
+++ b/python/plugins/processing/tests/testdata/expected/poly_boundary.gml
@ -0,0 +1,58 @@
+<?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_boundary.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>-1</gml:X><gml:Y>-3</gml:Y></gml:coord>
+      <gml:coord><gml:X>10</gml:X><gml:Y>6</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                                                             
+  <gml:featureMember>
+    <ogr:poly_boundary fid="polys.0">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>-1,-1 -1,3 3,3 3,2 2,2 2,-1 -1,-1</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:name>aaaaa</ogr:name>
+      <ogr:intval>33</ogr:intval>
+      <ogr:floatval>44.123456</ogr:floatval>
+    </ogr:poly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:poly_boundary fid="polys.1">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>5,5 6,4 4,4 5,5</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:name>Aaaaa</ogr:name>
+      <ogr:intval>-33</ogr:intval>
+      <ogr:floatval>0</ogr:floatval>
+    </ogr:poly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:poly_boundary fid="polys.2">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>2,5 2,6 3,6 3,5 2,5</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:name>bbaaa</ogr:name>
+      <ogr:floatval>0.123</ogr:floatval>
+    </ogr:poly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:poly_boundary fid="polys.3">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>6,1 10,1 10,-3 6,-3 6,1</gml:coordinates></gml:LineString></gml:lineStringMember><gml:lineStringMember><gml:LineString><gml:coordinates>7,0 7,-2 9,-2 9,0 7,0</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:name>ASDF</ogr:name>
+      <ogr:intval>0</ogr:intval>
+    </ogr:poly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:poly_boundary fid="polys.4">
+      <ogr:intval>120</ogr:intval>
+      <ogr:floatval>-100291.43213</ogr:floatval>
+    </ogr:poly_boundary>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:poly_boundary fid="polys.5">
+      <ogr:geometryProperty><gml:MultiLineString srsName="EPSG:4326"><gml:lineStringMember><gml:LineString><gml:coordinates>3,2 6,1 6,-3 2,-1 2,2 3,2</gml:coordinates></gml:LineString></gml:lineStringMember></gml:MultiLineString></ogr:geometryProperty>
+      <ogr:name>elim</ogr:name>
+      <ogr:intval>2</ogr:intval>
+      <ogr:floatval>3.33</ogr:floatval>
+    </ogr:poly_boundary>
+  </gml:featureMember>
+</ogr:FeatureCollection>
--- a/python/plugins/processing/tests/testdata/expected/poly_boundary.xsd
+++ b/python/plugins/processing/tests/testdata/expected/poly_boundary.xsd
@ -0,0 +1,43 @@
+<?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_boundary" type="ogr:poly_boundary_Type" substitutionGroup="gml:_Feature"/>
+<xs:complexType name="poly_boundary_Type">
+  <xs:complexContent>
+    <xs:extension base="gml:AbstractFeatureType">
+      <xs:sequence>
+        <xs:element name="geometryProperty" type="gml:MultiLineStringPropertyType" nillable="true" minOccurs="0" maxOccurs="1"/>
+        <xs:element name="name" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:string">
+              <xs:maxLength value="5"/>
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+        <xs:element name="intval" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:integer">
+              <xs:totalDigits value="16"/>
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+        <xs:element name="floatval" nillable="true" minOccurs="0" maxOccurs="1">
+          <xs:simpleType>
+            <xs:restriction base="xs:decimal">
+            </xs:restriction>
+          </xs:simpleType>
+        </xs:element>
+      </xs:sequence>
+    </xs:extension>
+  </xs:complexContent>
+</xs:complexType>
+</xs:schema>
--- a/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml
+++ b/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml
@ -506,3 +506,46 @@ tests:
        name: expected/multipoint_bounds.gml
        type: vector

+  - algorithm: qgis:boundary
+    name: Polygon boundary
+    params:
+      INPUT_LAYER:
+        name: polys.gml
+        type: vector
+    results:
+      OUTPUT_LAYER:
+        name: expected/poly_boundary.gml
+        type: vector
+
+  - algorithm: qgis:boundary
+    name: Multipoly boundary
+    params:
+      INPUT_LAYER:
+        name: multipolys.gml
+        type: vector
+    results:
+      OUTPUT_LAYER:
+        name: expected/multipoly_boundary.gml
+        type: vector
+
+  - algorithm: qgis:boundary
+    name: Line boundary
+    params:
+      INPUT_LAYER:
+        name: lines.gml
+        type: vector
+    results:
+      OUTPUT_LAYER:
+        name: expected/lines_boundary.gml
+        type: vector
+
+  - algorithm: qgis:boundary
+    name: Multiline boundary
+    params:
+      INPUT_LAYER:
+        name: multilines.gml
+        type: vector
+    results:
+      OUTPUT_LAYER:
+        name: expected/multiline_boundary.gml
+        type: vector