QGIS/python/plugins/grassprovider/ext/v_net_distance.py
2023-03-21 03:50:08 +10:00

79 lines
3.3 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
v_net_distance.py
---------------------
Date : December 2015
Copyright : (C) 2015 by Médéric Ribreux
Email : medspx at medspx dot fr
***************************************************************************
* *
* 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__ = 'Médéric Ribreux'
__date__ = 'December 2015'
__copyright__ = '(C) 2015, Médéric Ribreux'
import os
from .v_net import variableOutput
from processing.tools.system import getTempFilename
from qgis.core import QgsProcessingParameterString
def processCommand(alg, parameters, context, feedback):
""" Handle data preparation for v.net.distance:
* Integrate point layers into network vector map.
* Make v.net.distance use those layers.
* Delete the threshold parameter.
* If where statement, connect to the db
"""
# Grab the point layer and delete this parameter
lineLayer = alg.exportedLayers['input']
fromLayer = alg.exportedLayers['flayer']
toLayer = alg.exportedLayers['tlayer']
intLayer = 'bufnet' + os.path.basename(getTempFilename(context=context))
netLayer = 'net' + os.path.basename(getTempFilename(context=context))
threshold = alg.parameterAsDouble(parameters, 'threshold', context)
# Create the v.net connect command for from_layer integration
command = 'v.net -s input={} points={} output={} operation=connect threshold={} arc_layer=1 node_layer=2'.format(
lineLayer, fromLayer, intLayer, threshold)
alg.commands.append(command)
# Do it again with to_layer
command = 'v.net -s input={} points={} output={} operation=connect threshold={} arc_layer=1 node_layer=3'.format(
intLayer, toLayer, netLayer, threshold)
alg.commands.append(command)
# Connect the point layer database to the layer 2 of the network
command = 'v.db.connect -o map={} table={} layer=2'.format(netLayer, fromLayer)
alg.commands.append(command)
command = 'v.db.connect -o map={} table={} layer=3'.format(netLayer, toLayer)
alg.commands.append(command)
# remove undesired parameters
alg.removeParameter('flayer')
alg.removeParameter('tlayer')
alg.removeParameter('threshold')
alg.exportedLayers['input'] = netLayer
# Add the two new parameters
fLayer = QgsProcessingParameterString('from_layer', None, 2, False, False)
alg.addParameter(fLayer)
tLayer = QgsProcessingParameterString('to_layer', None, 3, False, False)
alg.addParameter(tLayer)
alg.processCommand(parameters, context, feedback)
def processOutputs(alg, parameters, context, feedback):
outputParameter = {'output': ['output', 'line', 1, True]}
variableOutput(alg, outputParameter, parameters, context)