QGIS/python/plugins/processing/algs/qgis/ReverseLineDirection.py
2017-06-06 13:41:42 +10:00

93 lines
3.5 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
ReverseLineDirection.py
-----------------------
Date : November 2015
Copyright : (C) 2015 by Nyall Dawson
Email : nyall dot dawson 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__ = 'Nyall Dawson'
__date__ = 'November 2015'
__copyright__ = '(C) 2015, Nyall Dawson'
# This will get replaced with a git SHA1 when you do a git archive323
__revision__ = '$Format:%H$'
from qgis.core import (QgsApplication,
QgsGeometry,
QgsFeature,
QgsProcessingUtils)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
from processing.core.parameters import ParameterVector
from processing.core.outputs import OutputVector
from processing.tools import dataobjects
class ReverseLineDirection(QgisAlgorithm):
INPUT_LAYER = 'INPUT_LAYER'
OUTPUT_LAYER = 'OUTPUT_LAYER'
def icon(self):
return QgsApplication.getThemeIcon("/providerQgis.svg")
def svgIconPath(self):
return QgsApplication.iconPath("providerQgis.svg")
def group(self):
return self.tr('Vector geometry tools')
def __init__(self):
super().__init__()
self.addParameter(ParameterVector(self.INPUT_LAYER,
self.tr('Input layer'), [dataobjects.TYPE_VECTOR_LINE]))
self.addOutput(OutputVector(self.OUTPUT_LAYER, self.tr('Reversed'), datatype=[dataobjects.TYPE_VECTOR_LINE]))
def name(self):
return 'reverselinedirection'
def displayName(self):
return self.tr('Reverse line direction')
def processAlgorithm(self, parameters, context, feedback):
layer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.INPUT_LAYER), context)
writer = self.getOutputFromName(
self.OUTPUT_LAYER).getVectorWriter(layer.fields(), layer.wkbType(), layer.crs(), context)
outFeat = QgsFeature()
features = QgsProcessingUtils.getFeatures(layer, context)
total = 100.0 / QgsProcessingUtils.featureCount(layer, context)
for current, inFeat in enumerate(features):
inGeom = inFeat.geometry()
attrs = inFeat.attributes()
outGeom = None
if not inGeom.isNull():
reversedLine = inGeom.geometry().reversed()
if not reversedLine:
raise GeoAlgorithmExecutionException(
self.tr('Error reversing line'))
outGeom = QgsGeometry(reversedLine)
outFeat.setGeometry(outGeom)
outFeat.setAttributes(attrs)
writer.addFeature(outFeat)
feedback.setProgress(int(current * total))
del writer