QGIS/python/plugins/processing/algs/qgis/SingleSidedBuffer.py
Harrissou Sant-anna 30aa5f5f96 Allow double typed values in algorithm
Also homogenize the output name
2017-10-27 13:09:39 +11:00

123 lines
4.7 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
SingleSidedBuffer.py
--------------------
Date : August 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__ = 'August 2016'
__copyright__ = '(C) 2016, Nyall Dawson'
# This will get replaced with a git SHA1 when you do a git archive323
__revision__ = '$Format:%H$'
from qgis.core import (QgsGeometry,
QgsWkbTypes,
QgsProcessing,
QgsProcessingParameterNumber,
QgsProcessingParameterEnum,
QgsProcessingException)
from processing.algs.qgis.QgisAlgorithm import QgisFeatureBasedAlgorithm
class SingleSidedBuffer(QgisFeatureBasedAlgorithm):
DISTANCE = 'DISTANCE'
SIDE = 'SIDE'
SEGMENTS = 'SEGMENTS'
JOIN_STYLE = 'JOIN_STYLE'
MITER_LIMIT = 'MITER_LIMIT'
def group(self):
return self.tr('Vector geometry')
def __init__(self):
super().__init__()
self.distance = None
self.segments = None
self.join_style = None
self.side = None
self.miter_limit = None
self.sides = [self.tr('Left'),
'Right']
self.join_styles = [self.tr('Round'),
'Miter',
'Bevel']
def initParameters(self, config=None):
self.addParameter(QgsProcessingParameterNumber(self.DISTANCE,
self.tr('Distance'), QgsProcessingParameterNumber.Double,
defaultValue=10.0))
self.addParameter(QgsProcessingParameterEnum(
self.SIDE,
self.tr('Side'),
options=self.sides))
self.addParameter(QgsProcessingParameterNumber(self.SEGMENTS,
self.tr('Segments'), QgsProcessingParameterNumber.Integer,
minValue=1, defaultValue=8))
self.addParameter(QgsProcessingParameterEnum(
self.JOIN_STYLE,
self.tr('Join style'),
options=self.join_styles))
self.addParameter(QgsProcessingParameterNumber(self.MITER_LIMIT,
self.tr('Miter limit'), QgsProcessingParameterNumber.Double,
minValue=1, defaultValue=2))
def name(self):
return 'singlesidedbuffer'
def displayName(self):
return self.tr('Single sided buffer')
def outputName(self):
return self.tr('Buffer')
def inputLayerTypes(self):
return [QgsProcessing.TypeVectorLine]
def outputType(self):
return QgsProcessing.TypeVectorPolygon
def outputWkbType(self, input_wkb_type):
return QgsWkbTypes.Polygon
def prepareAlgorithm(self, parameters, context, feedback):
self.distance = self.parameterAsDouble(parameters, self.DISTANCE, context)
self.segments = self.parameterAsInt(parameters, self.SEGMENTS, context)
self.join_style = self.parameterAsEnum(parameters, self.JOIN_STYLE, context) + 1
if self.parameterAsEnum(parameters, self.SIDE, context) == 0:
self.side = QgsGeometry.SideLeft
else:
self.side = QgsGeometry.SideRight
self.miter_limit = self.parameterAsDouble(parameters, self.MITER_LIMIT, context)
return True
def processFeature(self, feature, feedback):
input_geometry = feature.geometry()
if input_geometry:
output_geometry = input_geometry.singleSidedBuffer(self.distance, self.segments,
self.side, self.join_style, self.miter_limit)
if not output_geometry:
raise QgsProcessingException(
self.tr('Error calculating single sided buffer'))
feature.setGeometry(output_geometry)
return feature