QGIS/python/plugins/processing/algs/qgis/SnapGeometries.py
Nyall Dawson 636e9c5ea3 [FEATURE] Add geometry snapper modes to only snap end points of lines
Allows snapping of end points only, or end point to end point only

Also update processing algorithm to match
2017-03-30 15:52:49 +10:00

102 lines
4.2 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. *
* *
***************************************************************************
"""
__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,
QgsInternalGeometrySnapper)
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')
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.tr('Move end points only, prefer aligning nodes'),
self.tr('Move end points only, prefer closest point'),
self.tr('Snap end points to end points only')]
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)
if self.getParameterValue(self.INPUT) != self.getParameterValue(self.REFERENCE_LAYER):
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))
else:
# snapping internally
snapper = QgsInternalGeometrySnapper(tolerance, mode)
processed = 0
for f in features:
out_feature = f
out_feature.setGeometry(snapper.snapFeature(f))
writer.addFeature(out_feature)
processed += 1
feedback.setProgress(processed * self.total)
del writer
def featureSnapped(self):
self.processed += 1
self.feedback.setProgress(int(self.processed * self.total))