# -*- coding: utf-8 -*- """ *************************************************************************** SplitLines.py --------------------- Date : November 2014 Revised : February 2016 Copyright : (C) 2014 by Bernhard Ströbl Email : bernhard dot stroebl at jena dot de *************************************************************************** * * * 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. * * * *************************************************************************** """ from builtins import next __author__ = 'Bernhard Ströbl' __date__ = 'November 2014' __copyright__ = '(C) 2014, Bernhard Ströbl' # This will get replaced with a git SHA1 when you do a git archive __revision__ = '$Format:%H$' from qgis.core import Qgis, QgsFeatureRequest, QgsFeature, QgsGeometry, QgsWkbTypes from processing.core.GeoAlgorithm import GeoAlgorithm from processing.core.parameters import ParameterVector from processing.core.outputs import OutputVector from processing.core.ProcessingLog import ProcessingLog from processing.tools import dataobjects from processing.tools import vector class SplitLinesWithLines(GeoAlgorithm): INPUT_A = 'INPUT_A' INPUT_B = 'INPUT_B' OUTPUT = 'OUTPUT' def defineCharacteristics(self): self.name, self.i18n_name = self.trAlgorithm('Split lines with lines') self.group, self.i18n_group = self.trAlgorithm('Vector overlay tools') self.addParameter(ParameterVector(self.INPUT_A, self.tr('Input layer'), [dataobjects.TYPE_VECTOR_LINE])) self.addParameter(ParameterVector(self.INPUT_B, self.tr('Split layer'), [dataobjects.TYPE_VECTOR_LINE])) self.addOutput(OutputVector(self.OUTPUT, self.tr('Splitted'), datatype=[dataobjects.TYPE_VECTOR_LINE])) def processAlgorithm(self, progress): layerA = dataobjects.getObjectFromUri(self.getParameterValue(self.INPUT_A)) layerB = dataobjects.getObjectFromUri(self.getParameterValue(self.INPUT_B)) sameLayer = self.getParameterValue(self.INPUT_A) == self.getParameterValue(self.INPUT_B) fieldList = layerA.fields() writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fieldList, QgsWkbTypes.LineString, layerA.crs()) spatialIndex = vector.spatialindex(layerB) outFeat = QgsFeature() features = vector.features(layerA) total = 100.0 / float(len(features)) for current, inFeatA in enumerate(features): inGeom = inFeatA.geometry() attrsA = inFeatA.attributes() outFeat.setAttributes(attrsA) inLines = [inGeom] lines = spatialIndex.intersects(inGeom.boundingBox()) engine = None if len(lines) > 0: # use prepared geometries for faster intersection tests engine = QgsGeometry.createGeometryEngine(inGeom.geometry()) engine.prepareGeometry() if len(lines) > 0: # hasIntersections splittingLines = [] request = QgsFeatureRequest().setFilterFids(lines).setSubsetOfAttributes([]) for inFeatB in layerB.getFeatures(request): # check if trying to self-intersect if sameLayer: if inFeatA.id() == inFeatB.id(): continue splitGeom = inFeatB.geometry() if engine.intersects(splitGeom.geometry()): splittingLines.append(splitGeom) if len(splittingLines) > 0: for splitGeom in splittingLines: splitterPList = vector.extractPoints(splitGeom) outLines = [] split_geom_engine = QgsGeometry.createGeometryEngine(splitGeom.geometry()) split_geom_engine.prepareGeometry() while len(inLines) > 0: inGeom = inLines.pop() inPoints = vector.extractPoints(inGeom) if split_geom_engine.intersects(inGeom.geometry()): try: result, newGeometries, topoTestPoints = inGeom.splitGeometry(splitterPList, False) except: ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, self.tr('Geometry exception while splitting')) result = 1 # splitGeometry: If there are several intersections # between geometry and splitLine, only the first one is considered. if result == 0: # split occurred if inPoints == vector.extractPoints(inGeom): # bug in splitGeometry: sometimes it returns 0 but # the geometry is unchanged outLines.append(inGeom) else: inLines.append(inGeom) for aNewGeom in newGeometries: inLines.append(aNewGeom) else: outLines.append(inGeom) else: outLines.append(inGeom) inLines = outLines for aLine in inLines: if len(aLine.asPolyline()) > 2 or \ (len(aLine.asPolyline()) == 2 and aLine.asPolyline()[0] != aLine.asPolyline()[1]): # sometimes splitting results in lines of zero length outFeat.setGeometry(aLine) writer.addFeature(outFeat) progress.setPercentage(int(current * total)) del writer