QGIS/python/plugins/processing/algs/qgis/SymmetricalDifference.py
2017-10-16 23:00:53 +02:00

159 lines
6.2 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
SymmetricalDifference.py
---------------------
Date : September 2014
Copyright : (C) 2014 by Alexander Bruy
Email : alexander dot bruy 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__ = 'Alexander Bruy'
__date__ = 'September 2014'
__copyright__ = '(C) 2014, Alexander Bruy'
# 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.core import (QgsFeature,
QgsFeatureSink,
QgsGeometry,
QgsFeatureRequest,
NULL,
QgsWkbTypes,
QgsMessageLog,
QgsProcessingUtils,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterFeatureSink,
QgsSpatialIndex)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
from processing.tools import vector
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class SymmetricalDifference(QgisAlgorithm):
INPUT = 'INPUT'
OVERLAY = 'OVERLAY'
OUTPUT = 'OUTPUT'
def icon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'sym_difference.png'))
def group(self):
return self.tr('Vector overlay')
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT,
self.tr('Input layer')))
self.addParameter(QgsProcessingParameterFeatureSource(self.OVERLAY,
self.tr('Difference layer')))
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Symmetrical difference')))
def name(self):
return 'symmetricaldifference'
def displayName(self):
return self.tr('Symmetrical difference')
def processAlgorithm(self, parameters, context, feedback):
sourceA = self.parameterAsSource(parameters, self.INPUT, context)
sourceB = self.parameterAsSource(parameters, self.OVERLAY, context)
geomType = QgsWkbTypes.multiType(sourceA.wkbType())
fields = QgsProcessingUtils.combineFields(sourceA.fields(), sourceB.fields())
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
fields, geomType, sourceA.sourceCrs())
featB = QgsFeature()
outFeat = QgsFeature()
indexA = QgsSpatialIndex(sourceA, feedback)
indexB = QgsSpatialIndex(sourceB.getFeatures(QgsFeatureRequest().setSubsetOfAttributes([]).setDestinationCrs(sourceA.sourceCrs())), feedback)
total = 100.0 / (sourceA.featureCount() * sourceB.featureCount()) if sourceA.featureCount() and sourceB.featureCount() else 1
count = 0
for featA in sourceA.getFeatures():
if feedback.isCanceled():
break
geom = featA.geometry()
diffGeom = QgsGeometry(geom)
attrs = featA.attributes()
intersects = indexB.intersects(geom.boundingBox())
request = QgsFeatureRequest().setFilterFids(intersects).setSubsetOfAttributes([])
request.setDestinationCrs(sourceA.sourceCrs())
for featB in sourceB.getFeatures(request):
if feedback.isCanceled():
break
tmpGeom = featB.geometry()
if diffGeom.intersects(tmpGeom):
diffGeom = QgsGeometry(diffGeom.difference(tmpGeom))
try:
outFeat.setGeometry(diffGeom)
outFeat.setAttributes(attrs)
sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
except:
QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
self.tr('Processing'), QgsMessageLog.WARNING)
continue
count += 1
feedback.setProgress(int(count * total))
length = len(sourceA.fields())
for featA in sourceB.getFeatures(QgsFeatureRequest().setDestinationCrs(sourceA.sourceCrs())):
if feedback.isCanceled():
break
geom = featA.geometry()
diffGeom = QgsGeometry(geom)
attrs = featA.attributes()
attrs = [NULL] * length + attrs
intersects = indexA.intersects(geom.boundingBox())
request = QgsFeatureRequest().setFilterFids(intersects).setSubsetOfAttributes([])
for featB in sourceA.getFeatures(request):
if feedback.isCanceled():
break
tmpGeom = featB.geometry()
if diffGeom.intersects(tmpGeom):
diffGeom = QgsGeometry(diffGeom.difference(tmpGeom))
try:
outFeat.setGeometry(diffGeom)
outFeat.setAttributes(attrs)
sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
except:
QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
self.tr('Processing'), QgsMessageLog.WARNING)
continue
count += 1
feedback.setProgress(int(count * total))
return {self.OUTPUT: dest_id}