2017-08-22 23:36:42 +10:00

119 lines
4.4 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
Difference.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.core import (QgsFeature,
QgsFeatureSink,
QgsGeometry,
QgsFeatureRequest,
QgsWkbTypes,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterFeatureSink,
QgsSpatialIndex)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class Difference(QgisAlgorithm):
INPUT = 'INPUT'
OVERLAY = 'OVERLAY'
OUTPUT = 'OUTPUT'
def icon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', '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('Difference')))
def name(self):
return 'difference'
def displayName(self):
return self.tr('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())
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
sourceA.fields(), geomType, sourceA.sourceCrs())
featB = QgsFeature()
outFeat = QgsFeature()
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
if featA.hasGeometry():
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))
outFeat.setGeometry(diffGeom)
outFeat.setAttributes(attrs)
sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
else:
sink.addFeature(featA, QgsFeatureSink.FastInsert)
count += 1
feedback.setProgress(int(count * total))
return {self.OUTPUT: dest_id}