QGIS/python/plugins/processing/algs/qgis/PointsInPolygon.py
Nyall Dawson 86368f39c3 [processing] Optimise feature requests within qgis algs
- don't use setFilterFid() within loops to fetch features one
at time (as it's extremely slow), instead use setFilterFids()
outside the loop
- don't fetch unused attributes/geometry when it can be
avoided
2016-10-17 10:30:55 +10:00

118 lines
4.5 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
PointsInPolygon.py
---------------------
Date : August 2012
Copyright : (C) 2012 by Victor Olaya
Email : volayaf 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__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
import os
from qgis.PyQt.QtGui import QIcon
from qgis.PyQt.QtCore import QVariant
from qgis.core import QgsGeometry, QgsFeatureRequest, QgsFeature, QgsField
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterString
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 PointsInPolygon(GeoAlgorithm):
POLYGONS = 'POLYGONS'
POINTS = 'POINTS'
OUTPUT = 'OUTPUT'
FIELD = 'FIELD'
def getIcon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'sum_points.png'))
def defineCharacteristics(self):
self.name, self.i18n_name = self.trAlgorithm('Count points in polygon')
self.group, self.i18n_group = self.trAlgorithm('Vector analysis tools')
self.addParameter(ParameterVector(self.POLYGONS,
self.tr('Polygons'), [dataobjects.TYPE_VECTOR_POLYGON]))
self.addParameter(ParameterVector(self.POINTS,
self.tr('Points'), [dataobjects.TYPE_VECTOR_POINT]))
self.addParameter(ParameterString(self.FIELD,
self.tr('Count field name'), 'NUMPOINTS'))
self.addOutput(OutputVector(self.OUTPUT, self.tr('Count'), datatype=[dataobjects.TYPE_VECTOR_POLYGON]))
def processAlgorithm(self, progress):
polyLayer = dataobjects.getObjectFromUri(self.getParameterValue(self.POLYGONS))
pointLayer = dataobjects.getObjectFromUri(self.getParameterValue(self.POINTS))
fieldName = self.getParameterValue(self.FIELD)
fields = polyLayer.fields()
fields.append(QgsField(fieldName, QVariant.Int))
(idxCount, fieldList) = vector.findOrCreateField(polyLayer,
polyLayer.fields(), fieldName)
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
fields.toList(), polyLayer.wkbType(), polyLayer.crs())
spatialIndex = vector.spatialindex(pointLayer)
ftPoly = QgsFeature()
ftPoint = QgsFeature()
outFeat = QgsFeature()
geom = QgsGeometry()
features = vector.features(polyLayer)
total = 100.0 / len(features)
for current, ftPoly in enumerate(features):
geom = ftPoly.geometry()
engine = QgsGeometry.createGeometryEngine(geom.geometry())
engine.prepareGeometry()
attrs = ftPoly.attributes()
count = 0
points = spatialIndex.intersects(geom.boundingBox())
if len(points) > 0:
request = QgsFeatureRequest().setFilterFids(points).setSubsetOfAttributes([])
fit = pointLayer.getFeatures(request)
ftPoint = QgsFeature()
while fit.nextFeature(ftPoint):
tmpGeom = ftPoint.geometry()
if engine.contains(tmpGeom.geometry()):
count += 1
outFeat.setGeometry(geom)
if idxCount == len(attrs):
attrs.append(count)
else:
attrs[idxCount] = count
outFeat.setAttributes(attrs)
writer.addFeature(outFeat)
progress.setPercentage(int(current * total))
del writer