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

107 lines
4.0 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
Explode.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. *
* *
***************************************************************************
"""
from builtins import range
__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__ = '$Format:%H$'
from qgis.core import (QgsFeature,
QgsGeometry,
QgsFeatureSink,
QgsWkbTypes,
QgsProcessing,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterFeatureSink,
QgsLineString)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
class Explode(QgisAlgorithm):
INPUT = 'INPUT'
OUTPUT = 'OUTPUT'
def group(self):
return self.tr('Vector geometry')
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT,
self.tr('Input layer'), [QgsProcessing.TypeVectorLine]))
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT,
self.tr('Exploded'), QgsProcessing.TypeVectorLine))
def name(self):
return 'explodelines'
def displayName(self):
return self.tr('Explode lines')
def processAlgorithm(self, parameters, context, feedback):
source = self.parameterAsSource(parameters, self.INPUT, context)
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
source.fields(), QgsWkbTypes.singleType(source.wkbType()), source.sourceCrs())
features = source.getFeatures()
total = 100.0 / source.featureCount() if source.featureCount() else 0
for current, feature in enumerate(features):
if feedback.isCanceled():
break
feedback.setProgress(int(current * total))
if not feature.hasGeometry():
sink.addFeature(feature, QgsFeatureSink.FastInsert)
continue
outFeat = QgsFeature()
inGeom = feature.geometry()
segments = self.extractAsSingleSegments(inGeom)
outFeat.setAttributes(feature.attributes())
for segment in segments:
outFeat.setGeometry(segment)
sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
return {self.OUTPUT: dest_id}
def extractAsSingleSegments(self, geom):
segments = []
if geom.isMultipart():
for part in range(geom.geometry().numGeometries()):
segments.extend(self.getPolylineAsSingleSegments(geom.geometry().geometryN(part)))
else:
segments.extend(self.getPolylineAsSingleSegments(
geom.geometry()))
return segments
def getPolylineAsSingleSegments(self, polyline):
segments = []
for i in range(polyline.numPoints() - 1):
ptA = polyline.pointN(i)
ptB = polyline.pointN(i + 1)
segment = QgsGeometry(QgsLineString([ptA, ptB]))
segments.append(segment)
return segments