QGIS/python/plugins/processing/algs/qgis/DensifyGeometries.py
Nyall Dawson b90aa916e6 Port processing Densify Geometries algorithm to use c++ densify
Rough benchmark using 50k geometry polygon shapefile

Before: 1m25s
After:  21s
2017-03-25 16:23:29 +10:00

84 lines
3.2 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
DensifyGeometries.py
---------------------
Date : October 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. *
* *
***************************************************************************
"""
from builtins import range
__author__ = 'Victor Olaya'
__date__ = 'October 2012'
__copyright__ = '(C) 2012, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
import os
from qgis.core import QgsGeometry, QgsPoint, QgsWkbTypes
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterNumber
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 DensifyGeometries(GeoAlgorithm):
INPUT = 'INPUT'
VERTICES = 'VERTICES'
OUTPUT = 'OUTPUT'
def defineCharacteristics(self):
self.name, self.i18n_name = self.trAlgorithm('Densify geometries')
self.group, self.i18n_group = self.trAlgorithm('Vector geometry tools')
self.tags = self.tr('add,vertices,points')
self.addParameter(ParameterVector(self.INPUT,
self.tr('Input layer'),
[dataobjects.TYPE_VECTOR_POLYGON, dataobjects.TYPE_VECTOR_LINE]))
self.addParameter(ParameterNumber(self.VERTICES,
self.tr('Vertices to add'), 1, 10000000, 1))
self.addOutput(OutputVector(self.OUTPUT,
self.tr('Densified')))
def processAlgorithm(self, feedback):
layer = dataobjects.getObjectFromUri(
self.getParameterValue(self.INPUT))
vertices = self.getParameterValue(self.VERTICES)
isPolygon = layer.geometryType() == QgsWkbTypes.PolygonGeometry
writer = self.getOutputFromName(
self.OUTPUT).getVectorWriter(layer.fields().toList(),
layer.wkbType(), layer.crs())
features = vector.features(layer)
total = 100.0 / len(features)
for current, f in enumerate(features):
feature = f
if feature.hasGeometry():
new_geometry = feature.geometry().densifyByCount(int(vertices))
feature.setGeometry(new_geometry)
writer.addFeature(feature)
feedback.setProgress(int(current * total))
del writer