mirror of
https://github.com/qgis/QGIS.git
synced 2025-03-06 00:05:02 -05:00
06c4b07222
Since the layer has more complete knowledge of the crs (ie, when provider could not determine crs and user has selected it from the list), and also better knowledge of layer fields (virtual fields, joined fields) we should use these rather than the provider methods.
92 lines
3.2 KiB
Python
92 lines
3.2 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
"""
|
|
***************************************************************************
|
|
Centroids.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. *
|
|
* *
|
|
***************************************************************************
|
|
"""
|
|
|
|
__author__ = 'Victor Olaya'
|
|
__date__ = 'August 2012'
|
|
__copyright__ = '(C) 2012, Victor Olaya'
|
|
|
|
# This will get replaced with a git SHA1 when you do a git archive323
|
|
|
|
__revision__ = '$Format:%H$'
|
|
|
|
import os
|
|
|
|
from qgis.PyQt.QtGui import QIcon
|
|
|
|
from qgis.core import Qgis, QgsGeometry, QgsFeature, QgsWkbTypes
|
|
|
|
from processing.core.GeoAlgorithm import GeoAlgorithm
|
|
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
|
|
from processing.core.parameters import ParameterVector
|
|
from processing.core.outputs import OutputVector
|
|
from processing.tools import dataobjects, vector
|
|
|
|
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
|
|
|
|
|
|
class Centroids(GeoAlgorithm):
|
|
|
|
INPUT_LAYER = 'INPUT_LAYER'
|
|
OUTPUT_LAYER = 'OUTPUT_LAYER'
|
|
|
|
def getIcon(self):
|
|
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'centroids.png'))
|
|
|
|
def defineCharacteristics(self):
|
|
self.name, self.i18n_name = self.trAlgorithm('Polygon centroids')
|
|
self.group, self.i18n_group = self.trAlgorithm('Vector geometry tools')
|
|
|
|
self.addParameter(ParameterVector(self.INPUT_LAYER,
|
|
self.tr('Input layer'), [ParameterVector.VECTOR_TYPE_POLYGON]))
|
|
|
|
self.addOutput(OutputVector(self.OUTPUT_LAYER, self.tr('Centroids')))
|
|
|
|
def processAlgorithm(self, progress):
|
|
layer = dataobjects.getObjectFromUri(
|
|
self.getParameterValue(self.INPUT_LAYER))
|
|
|
|
writer = self.getOutputFromName(
|
|
self.OUTPUT_LAYER).getVectorWriter(
|
|
layer.fields(),
|
|
QgsWkbTypes.Point,
|
|
layer.crs())
|
|
|
|
outFeat = QgsFeature()
|
|
|
|
features = vector.features(layer)
|
|
total = 100.0 / len(features)
|
|
for current, feat in enumerate(features):
|
|
inGeom = feat.geometry()
|
|
attrs = feat.attributes()
|
|
|
|
if inGeom.isEmpty():
|
|
outGeom = QgsGeometry(None)
|
|
else:
|
|
outGeom = QgsGeometry(inGeom.centroid())
|
|
if not outGeom:
|
|
raise GeoAlgorithmExecutionException(
|
|
self.tr('Error calculating centroid'))
|
|
|
|
outFeat.setGeometry(outGeom)
|
|
outFeat.setAttributes(attrs)
|
|
writer.addFeature(outFeat)
|
|
progress.setPercentage(int(current * total))
|
|
|
|
del writer
|