Port Points From Polygons to new API

qgis · Aug 13, 2017 · c6b3855 · c6b3855
1 parent c8ac784
commit c6b3855
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Showing 3 changed files with 50 additions and 30 deletions.
diff --git a/python/plugins/processing/algs/qgis/PointsFromPolygons.py b/python/plugins/processing/algs/qgis/PointsFromPolygons.py
@@ -28,29 +28,30 @@
 __revision__ = '$Format:%H$'
 
 from osgeo import gdal
-from qgis.core import (QgsApplication,
+from qgis.core import (QgsFeatureRequest,
                        QgsFields,
                        QgsField,
                        QgsFeature,
                        QgsFeatureSink,
                        QgsGeometry,
                        QgsWkbTypes,
-                       QgsPointXY,
-                       QgsProcessingUtils)
+                       QgsProcessingParameterBand,
+                       QgsPoint,
+                       QgsProcessing,
+                       QgsProcessingParameterRasterLayer,
+                       QgsProcessingParameterFeatureSource,
+                       QgsProcessingParameterFeatureSink)
 from qgis.PyQt.QtCore import QVariant
 from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
-from processing.core.parameters import ParameterRaster
-from processing.core.parameters import ParameterVector
-from processing.core.outputs import OutputVector
-from processing.tools import dataobjects, raster
+from processing.tools import raster
+from processing.tools.dataobjects import exportRasterLayer
 
 
 class PointsFromPolygons(QgisAlgorithm):
 
     INPUT_RASTER = 'INPUT_RASTER'
-    RASTER_BAND = 'RASTER_BAND'
     INPUT_VECTOR = 'INPUT_VECTOR'
-    OUTPUT_LAYER = 'OUTPUT_LAYER'
+    OUTPUT = 'OUTPUT'
 
     def group(self):
         return self.tr('Vector analysis tools')
@@ -59,11 +60,11 @@ def __init__(self):
         super().__init__()
 
     def initAlgorithm(self, config=None):
-        self.addParameter(ParameterRaster(self.INPUT_RASTER,
-                                          self.tr('Raster layer')))
-        self.addParameter(ParameterVector(self.INPUT_VECTOR,
-                                          self.tr('Vector layer'), [dataobjects.TYPE_VECTOR_POLYGON]))
-        self.addOutput(OutputVector(self.OUTPUT_LAYER, self.tr('Points from polygons'), datatype=[dataobjects.TYPE_VECTOR_POINT]))
+        self.addParameter(QgsProcessingParameterRasterLayer(self.INPUT_RASTER,
+                                                            self.tr('Raster layer')))
+        self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT_VECTOR,
+                                                              self.tr('Vector layer'), [QgsProcessing.TypeVectorPolygon]))
+        self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Points from polygons'), QgsProcessing.TypeVectorPoint))
 
     def name(self):
         return 'generatepointspixelcentroidsinsidepolygons'
@@ -72,21 +73,21 @@ def displayName(self):
         return self.tr('Generate points (pixel centroids) inside polygons')
 
     def processAlgorithm(self, parameters, context, feedback):
-        layer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.INPUT_VECTOR), context)
+        source = self.parameterAsSource(parameters, self.INPUT_VECTOR, context)
 
-        rasterPath = str(self.getParameterValue(self.INPUT_RASTER))
+        raster_layer = self.parameterAsRasterLayer(parameters, self.INPUT_RASTER, context)
+        rasterPath = exportRasterLayer(raster_layer)
 
         rasterDS = gdal.Open(rasterPath, gdal.GA_ReadOnly)
         geoTransform = rasterDS.GetGeoTransform()
-        rasterDS = None
 
         fields = QgsFields()
         fields.append(QgsField('id', QVariant.Int, '', 10, 0))
         fields.append(QgsField('poly_id', QVariant.Int, '', 10, 0))
         fields.append(QgsField('point_id', QVariant.Int, '', 10, 0))
 
-        writer = self.getOutputFromName(self.OUTPUT_LAYER).getVectorWriter(fields, QgsWkbTypes.Point,
-                                                                           layer.crs(), context)
+        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
+                                               fields, QgsWkbTypes.PointZ, raster_layer.crs())
 
         outFeature = QgsFeature()
         outFeature.setFields(fields)
@@ -95,9 +96,15 @@ def processAlgorithm(self, parameters, context, feedback):
         polyId = 0
         pointId = 0
 
-        features = QgsProcessingUtils.getFeatures(layer, context)
-        total = 100.0 / layer.featureCount() if layer.featureCount() else 0
+        features = source.getFeatures(QgsFeatureRequest().setDestinationCrs(raster_layer.crs()))
+        total = 100.0 / source.featureCount() if source.featureCount() else 0
         for current, f in enumerate(features):
+            if feedback.isCanceled():
+                break
+
+            if not f.hasGeometry():
+                continue
+
             geom = f.geometry()
             bbox = geom.boundingBox()
 
@@ -115,10 +122,11 @@ def processAlgorithm(self, parameters, context, feedback):
 
             for row in range(startRow, endRow + 1):
                 for col in range(startColumn, endColumn + 1):
+                    if feedback.isCanceled():
+                        break
+
                     (x, y) = raster.pixelToMap(row, col, geoTransform)
-                    point = QgsPointXY()
-                    point.setX(x)
-                    point.setY(y)
+                    point = QgsPoint(x, y)
 
                     if engine.contains(point):
                         outFeature.setGeometry(QgsGeometry(point))
@@ -129,11 +137,11 @@ def processAlgorithm(self, parameters, context, feedback):
                         fid += 1
                         pointId += 1
 
-                        writer.addFeature(outFeature, QgsFeatureSink.FastInsert)
+                        sink.addFeature(outFeature, QgsFeatureSink.FastInsert)
 
             pointId = 0
             polyId += 1
 
             feedback.setProgress(int(current * total))
 
-        del writer
+        return {self.OUTPUT: dest_id}
diff --git a/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py b/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
@@ -95,6 +95,7 @@
 from .PointOnSurface import PointOnSurface
 from .PointsAlongGeometry import PointsAlongGeometry
 from .PointsDisplacement import PointsDisplacement
+from .PointsFromPolygons import PointsFromPolygons
 from .PointsInPolygon import PointsInPolygon
 from .PointsLayerFromTable import PointsLayerFromTable
 from .PointsToPaths import PointsToPaths
@@ -154,7 +155,6 @@
 # from .GeometryConvert import GeometryConvert
 # from .FieldsCalculator import FieldsCalculator
 # from .FieldPyculator import FieldsPyculator
-# from .PointsFromPolygons import PointsFromPolygons
 # from .PointsFromLines import PointsFromLines
 # from .SetVectorStyle import SetVectorStyle
 # from .SetRasterStyle import SetRasterStyle
@@ -191,9 +191,6 @@ def getAlgs(self):
         #         SpatialJoin(),
         #         GeometryConvert(), FieldsCalculator(),
         #         FieldsPyculator(),
-        #
-        #         RasterLayerStatistics(),
-        #         PointsFromPolygons(),
         #         PointsFromLines(),
         #         SetVectorStyle(), SetRasterStyle(),
         #          HypsometricCurves(),
@@ -262,6 +259,7 @@ def getAlgs(self):
                 PointOnSurface(),
                 PointsAlongGeometry(),
                 PointsDisplacement(),
+                PointsFromPolygons(),
                 PointsInPolygon(),
                 PointsLayerFromTable(),
                 PointsToPaths(),

diff --git a/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml b/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml
@@ -2919,3 +2919,17 @@ tests:
       OUTPUT:
         name: expected/displaced_points.gml
         type: vector
+
+  - algorithm: qgis:generatepointspixelcentroidsinsidepolygons
+    name: Pixel centroids inside polygon
+    params:
+      INPUT_RASTER:
+        name: dem.tif
+        type: raster
+      INPUT_VECTOR:
+        name: custom/pixel_polygons.gml
+        type: vector
+    results:
+      OUTPUT:
+        name: expected/pixel_centroids_polygon.gml
+        type: vector