Port Difference & Sym.Diff. to C++, cleanups and tests

Author: wonder-sk

python/plugins/processing/algs/help/qgis.yaml

@@ -135,11 +135,6 @@ qgis:densifygeometriesgivenaninterval: >
 
   The distance is expressed in the same units used by the layer CRS.
 
-qgis:difference: >
-  This algorithm extracts features from the Input layer that fall outside, or partially overlap, features in the Difference layer. Input layer features that partially overlap the difference layer feature(s) are split along the boundary of the difference layer feature(s) and only the portions outside the difference layer features are retained.
-
-  Attributes are not modified.
-
 qgis:dissolve: >
   This algorithm takes a polygon or line vector layer and combines their geometries into new geometries. One or more attributes can be specified to dissolve only geometries belonging to the same class (having the same value for the specified attributes), alternatively all geometries can be dissolved.
 
@@ -511,10 +506,6 @@ qgis:sumlinelengths: >
 
   The resulting layer has the same features as the input polygon layer, but with two additional attributes containing the length and count of the lines across each polygon. The names of these two fields can be configured in the algorithm parameters.
 
-qgis:symmetricaldifference: >
-  This algorithm creates a layer containing features from both the Input and Difference layers but with the overlapping areas between the two layers removed. The attribute table of the Symmetrical Difference layer contains attributes from both the Input and Difference layers.
-
-
 qgis:texttofloat: >
   This algorithm modifies the type of a given attribute in a vector layer, converting a text attribute containing numeric strings into a numeric attribute.
 

python/plugins/processing/algs/qgis/Difference.py

@@ -57,7 +57,6 @@
 from .DeleteDuplicateGeometries import DeleteDuplicateGeometries
 from .DensifyGeometries import DensifyGeometries
 from .DensifyGeometriesInterval import DensifyGeometriesInterval
-from .Difference import Difference
 from .EliminateSelection import EliminateSelection
 from .ExecuteSQL import ExecuteSQL
 from .ExportGeometryInfo import ExportGeometryInfo
@@ -134,7 +133,6 @@
 from .SpatialJoinSummary import SpatialJoinSummary
 from .StatisticsByCategories import StatisticsByCategories
 from .SumLines import SumLines
-from .SymmetricalDifference import SymmetricalDifference
 from .TextToFloat import TextToFloat
 from .TinInterpolation import TinInterpolation
 from .TopoColors import TopoColor
@@ -175,7 +173,6 @@ def getAlgs(self):
                 DeleteDuplicateGeometries(),
                 DensifyGeometries(),
                 DensifyGeometriesInterval(),
-                Difference(),
                 EliminateSelection(),
                 ExecuteSQL(),
                 ExportGeometryInfo(),
@@ -252,7 +249,6 @@ def getAlgs(self):
                 SpatialJoinSummary(),
                 StatisticsByCategories(),
                 SumLines(),
-                SymmetricalDifference(),
                 TextToFloat(),
                 TinInterpolation(),
                 TopoColor(),

python/plugins/processing/algs/qgis/QgisAlgorithmProvider.py

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ difference1_a_b.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>9</gml:X><gml:Y>11</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                                                               
+  <gml:featureMember>
+    <ogr:difference1_a_b fid="difference1_a_b.0">
+      <ogr:geometryProperty><gml:MultiPolygon srsName="EPSG:3857"><gml:polygonMember><gml:Polygon><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>2,5 2,3 1,3 1,5 2,5</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></gml:polygonMember><gml:polygonMember><gml:Polygon><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>1,6 1,11 8,11 8,10 2,10 2,6 1,6</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></gml:polygonMember></gml:MultiPolygon></ogr:geometryProperty>
+      <ogr:id_a>A1</ogr:id_a>
+    </ogr:difference1_a_b>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:difference1_a_b fid="difference1_a_b.1">
+      <ogr:geometryProperty><gml:MultiPolygon srsName="EPSG:3857"><gml:polygonMember><gml:Polygon><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>3,3 3,4 4,4 4,3 3,3</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></gml:polygonMember></gml:MultiPolygon></ogr:geometryProperty>
+      <ogr:id_a>A4</ogr:id_a>
+    </ogr:difference1_a_b>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:difference1_a_b fid="difference1_a_b.2">
+      <ogr:geometryProperty><gml:MultiPolygon srsName="EPSG:3857"><gml:polygonMember><gml:Polygon><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>4,6 6,6 6,5 4,5 4,6</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></gml:polygonMember></gml:MultiPolygon></ogr:geometryProperty>
+      <ogr:id_a>A2</ogr:id_a>
+    </ogr:difference1_a_b>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:difference1_a_b fid="difference1_a_b.3">
+      <ogr:geometryProperty><gml:MultiPolygon srsName="EPSG:3857"><gml:polygonMember><gml:Polygon><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>7,7 6,7 6,8 7,8 7,7</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></gml:polygonMember><gml:polygonMember><gml:Polygon><gml:outerBoundaryIs><gml:LinearRing><gml:coordinates>8,8 9,8 9,7 8,7 8,8</gml:coordinates></gml:LinearRing></gml:outerBoundaryIs></gml:Polygon></gml:polygonMember></gml:MultiPolygon></ogr:geometryProperty>
+      <ogr:id_a>A3</ogr:id_a>
+    </ogr:difference1_a_b>
+  </gml:featureMember>
+</ogr:FeatureCollection>