mirror of
https://github.com/qgis/QGIS.git
synced 2025-03-06 00:05:02 -05:00
b6fb41d4ee
Instead, parameters evaluate to QgsFeatureSource, which are used for retrieving features, feature count, crs, wkb type, etc. This abstracts away the actual feature source, so that algorithms may potentially operate from non-layer feature sources. It also helps remove the need for specialised QgsProcessingUtils methods like getFeatures, featureCount, and createSpatialIndex. Instead the standard API methods using QgsFeatureSources can be used instead.
108 lines
4.2 KiB
Python
108 lines
4.2 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
"""
|
|
***************************************************************************
|
|
Boundary.py
|
|
--------------
|
|
Date : July 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__ = 'July 2016'
|
|
__copyright__ = '(C) 2016, Nyall Dawson'
|
|
|
|
# This will get replaced with a git SHA1 when you do a git archive323
|
|
|
|
__revision__ = '$Format:%H$'
|
|
|
|
import os
|
|
|
|
from qgis.core import (QgsGeometry,
|
|
QgsWkbTypes,
|
|
QgsProcessingUtils,
|
|
QgsProcessingParameterDefinition,
|
|
QgsProcessingParameterFeatureSource,
|
|
QgsProcessingParameterFeatureSink,
|
|
QgsProcessingOutputVectorLayer)
|
|
|
|
from qgis.PyQt.QtGui import QIcon
|
|
|
|
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
|
|
|
|
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
|
|
|
|
|
|
class Boundary(QgisAlgorithm):
|
|
|
|
INPUT_LAYER = 'INPUT_LAYER'
|
|
OUTPUT_LAYER = 'OUTPUT_LAYER'
|
|
|
|
def __init__(self):
|
|
super().__init__()
|
|
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT_LAYER, self.tr('Input layer'), [QgsProcessingParameterDefinition.TypeVectorLine, QgsProcessingParameterDefinition.TypeVectorPolygon]))
|
|
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT_LAYER, self.tr('Boundary')))
|
|
self.addOutput(QgsProcessingOutputVectorLayer(self.OUTPUT_LAYER, self.tr("Boundaries")))
|
|
|
|
def icon(self):
|
|
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'convex_hull.png'))
|
|
|
|
def group(self):
|
|
return self.tr('Vector geometry tools')
|
|
|
|
def name(self):
|
|
return 'boundary'
|
|
|
|
def displayName(self):
|
|
return self.tr('Boundary')
|
|
|
|
def processAlgorithm(self, parameters, context, feedback):
|
|
source = self.parameterAsSource(parameters, self.INPUT_LAYER, context)
|
|
|
|
input_wkb = source.wkbType()
|
|
if QgsWkbTypes.geometryType(input_wkb) == QgsWkbTypes.LineGeometry:
|
|
output_wkb = QgsWkbTypes.MultiPoint
|
|
elif QgsWkbTypes.geometryType(input_wkb) == QgsWkbTypes.PolygonGeometry:
|
|
output_wkb = QgsWkbTypes.MultiLineString
|
|
if QgsWkbTypes.hasZ(input_wkb):
|
|
output_wkb = QgsWkbTypes.addZ(output_wkb)
|
|
if QgsWkbTypes.hasM(input_wkb):
|
|
output_wkb = QgsWkbTypes.addM(output_wkb)
|
|
|
|
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT_LAYER, context, '',
|
|
source.fields(), output_wkb, source.crs())
|
|
|
|
features = source.getFeatures()
|
|
total = 100.0 / source.featureCount()
|
|
|
|
for current, input_feature in enumerate(features):
|
|
if feedback.isCanceled():
|
|
break
|
|
output_feature = input_feature
|
|
input_geometry = input_feature.geometry()
|
|
if input_geometry:
|
|
output_geometry = QgsGeometry(input_geometry.geometry().boundary())
|
|
if not output_geometry:
|
|
raise GeoAlgorithmExecutionException(
|
|
self.tr('Error calculating boundary'))
|
|
|
|
output_feature.setGeometry(output_geometry)
|
|
|
|
sink.addFeature(output_feature)
|
|
feedback.setProgress(int(current * total))
|
|
|
|
return {self.OUTPUT_LAYER: dest_id}
|