QGIS/python/plugins/processing/algs/qgis/SnapGeometries.py
2017-01-11 11:35:19 +01:00

88 lines
3.4 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
SnapGeometries.py
-----------------
Date : October 2016
Copyright : (C) 2016 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. *
* *
***************************************************************************
"""
from builtins import str
__author__ = 'Nyall Dawson'
__date__ = 'October 2016'
__copyright__ = '(C) 2016, Nyall Dawson'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
from qgis.analysis import QgsGeometrySnapper
from qgis.core import QgsFeature
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector, ParameterNumber, ParameterSelection
from processing.core.outputs import OutputVector
from processing.tools import dataobjects, vector
class SnapGeometriesToLayer(GeoAlgorithm):
INPUT = 'INPUT'
REFERENCE_LAYER = 'REFERENCE_LAYER'
TOLERANCE = 'TOLERANCE'
OUTPUT = 'OUTPUT'
BEHAVIOR = 'BEHAVIOR'
def defineCharacteristics(self):
self.name, self.i18n_name = self.trAlgorithm('Snap geometries to layer')
self.group, self.i18n_group = self.trAlgorithm('Vector geometry tools')
self.addParameter(ParameterVector(self.INPUT, self.tr('Input layer')))
self.addParameter(ParameterVector(self.REFERENCE_LAYER, self.tr('Reference layer')))
self.addParameter(ParameterNumber(self.TOLERANCE, self.tr('Tolerance (layer units)'), 0.00000001, 9999999999, default=10.0))
self.modes = [self.tr('Prefer aligning nodes'),
self.tr('Prefer closest point')]
self.addParameter(ParameterSelection(
self.BEHAVIOR,
self.tr('Behavior'),
self.modes, default=0))
self.addOutput(OutputVector(self.OUTPUT, self.tr('Snapped geometries')))
def processAlgorithm(self, feedback):
layer = dataobjects.getObjectFromUri(self.getParameterValue(self.INPUT))
reference_layer = dataobjects.getObjectFromUri(self.getParameterValue(self.REFERENCE_LAYER))
tolerance = self.getParameterValue(self.TOLERANCE)
mode = self.getParameterValue(self.BEHAVIOR)
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
layer.fields(), layer.wkbType(), layer.crs())
features = vector.features(layer)
self.processed = 0
self.feedback = feedback
self.total = 100.0 / len(features)
snapper = QgsGeometrySnapper(reference_layer)
snapper.featureSnapped.connect(self.featureSnapped)
snapped_features = snapper.snapFeatures(features, tolerance, mode)
for f in snapped_features:
writer.addFeature(QgsFeature(f))
del writer
def featureSnapped(self):
self.processed += 1
self.feedback.setProgress(int(self.processed * self.total))