QGIS/python/plugins/grassprovider/ext/v_net_distance.py
2024-11-29 15:38:02 +01:00

79 lines
3.2 KiB
Python

"""
***************************************************************************
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 = f"v.db.connect -o map={netLayer} table={fromLayer} layer=2"
alg.commands.append(command)
command = f"v.db.connect -o map={netLayer} table={toLayer} layer=3"
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)