mirror of
https://github.com/qgis/QGIS.git
synced 2025-03-10 00:13:55 -04:00
ccb72ebce2
- Output interpolated points when travel cost falls mid-way along an edge - Output all intermediate reachable points also - Make outputting upper/lower bound points optional, and non-default. Now by default we just output all definitely reachable points and the interpolated points along edges which correspond to the travel cost. This allows the output to be used to correctly generate service areas e.g. by concave/convex polygons and all reachable nodes will be included in the area. - Allow algorithm to optionally output a line layer (and make the point layer optional too, and default to just the line layer output) containing all reachable line segments (including interpolated segments of lines when the travel cost sits midway along that edge). This output is more easily understandably for users.
327 lines
15 KiB
Python
327 lines
15 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
"""
|
|
***************************************************************************
|
|
ServiceAreaFromPoint.py
|
|
---------------------
|
|
Date : December 2016
|
|
Copyright : (C) 2016 by Alexander Bruy
|
|
Email : alexander dot bruy 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__ = 'Alexander Bruy'
|
|
__date__ = 'December 2016'
|
|
__copyright__ = '(C) 2016, Alexander Bruy'
|
|
|
|
# This will get replaced with a git SHA1 when you do a git archive
|
|
|
|
__revision__ = '$Format:%H$'
|
|
|
|
import os
|
|
from collections import OrderedDict
|
|
|
|
from qgis.PyQt.QtCore import QVariant, QCoreApplication
|
|
from qgis.PyQt.QtGui import QIcon
|
|
|
|
from qgis.core import (QgsWkbTypes,
|
|
QgsUnitTypes,
|
|
QgsFeature,
|
|
QgsFeatureSink,
|
|
QgsGeometry,
|
|
QgsGeometryUtils,
|
|
QgsFields,
|
|
QgsField,
|
|
QgsProcessing,
|
|
QgsProcessingParameterBoolean,
|
|
QgsProcessingParameterEnum,
|
|
QgsProcessingParameterPoint,
|
|
QgsProcessingParameterField,
|
|
QgsProcessingParameterNumber,
|
|
QgsProcessingParameterString,
|
|
QgsProcessingParameterFeatureSink,
|
|
QgsProcessingParameterFeatureSource,
|
|
QgsProcessingParameterDefinition)
|
|
from qgis.analysis import (QgsVectorLayerDirector,
|
|
QgsNetworkDistanceStrategy,
|
|
QgsNetworkSpeedStrategy,
|
|
QgsGraphBuilder,
|
|
QgsGraphAnalyzer
|
|
)
|
|
|
|
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
|
|
|
|
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
|
|
|
|
|
|
class ServiceAreaFromPoint(QgisAlgorithm):
|
|
|
|
INPUT = 'INPUT'
|
|
START_POINT = 'START_POINT'
|
|
STRATEGY = 'STRATEGY'
|
|
TRAVEL_COST = 'TRAVEL_COST'
|
|
DIRECTION_FIELD = 'DIRECTION_FIELD'
|
|
VALUE_FORWARD = 'VALUE_FORWARD'
|
|
VALUE_BACKWARD = 'VALUE_BACKWARD'
|
|
VALUE_BOTH = 'VALUE_BOTH'
|
|
DEFAULT_DIRECTION = 'DEFAULT_DIRECTION'
|
|
SPEED_FIELD = 'SPEED_FIELD'
|
|
DEFAULT_SPEED = 'DEFAULT_SPEED'
|
|
TOLERANCE = 'TOLERANCE'
|
|
INCLUDE_BOUNDS = 'INCLUDE_BOUNDS'
|
|
OUTPUT = 'OUTPUT'
|
|
OUTPUT_LINES = 'OUTPUT_LINES'
|
|
|
|
def icon(self):
|
|
return QIcon(os.path.join(pluginPath, 'images', 'networkanalysis.svg'))
|
|
|
|
def group(self):
|
|
return self.tr('Network analysis')
|
|
|
|
def groupId(self):
|
|
return 'networkanalysis'
|
|
|
|
def __init__(self):
|
|
super().__init__()
|
|
|
|
def initAlgorithm(self, config=None):
|
|
self.DIRECTIONS = OrderedDict([
|
|
(self.tr('Forward direction'), QgsVectorLayerDirector.DirectionForward),
|
|
(self.tr('Backward direction'), QgsVectorLayerDirector.DirectionBackward),
|
|
(self.tr('Both directions'), QgsVectorLayerDirector.DirectionBoth)])
|
|
|
|
self.STRATEGIES = [self.tr('Shortest'),
|
|
self.tr('Fastest')
|
|
]
|
|
|
|
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT,
|
|
self.tr('Vector layer representing network'),
|
|
[QgsProcessing.TypeVectorLine]))
|
|
self.addParameter(QgsProcessingParameterPoint(self.START_POINT,
|
|
self.tr('Start point')))
|
|
self.addParameter(QgsProcessingParameterEnum(self.STRATEGY,
|
|
self.tr('Path type to calculate'),
|
|
self.STRATEGIES,
|
|
defaultValue=0))
|
|
self.addParameter(QgsProcessingParameterNumber(self.TRAVEL_COST,
|
|
self.tr('Travel cost (distance for "Shortest", time for "Fastest")'),
|
|
QgsProcessingParameterNumber.Double,
|
|
0.0, False, 0, 99999999.99))
|
|
|
|
params = []
|
|
params.append(QgsProcessingParameterField(self.DIRECTION_FIELD,
|
|
self.tr('Direction field'),
|
|
None,
|
|
self.INPUT,
|
|
optional=True))
|
|
params.append(QgsProcessingParameterString(self.VALUE_FORWARD,
|
|
self.tr('Value for forward direction'),
|
|
optional=True))
|
|
params.append(QgsProcessingParameterString(self.VALUE_BACKWARD,
|
|
self.tr('Value for backward direction'),
|
|
optional=True))
|
|
params.append(QgsProcessingParameterString(self.VALUE_BOTH,
|
|
self.tr('Value for both directions'),
|
|
optional=True))
|
|
params.append(QgsProcessingParameterEnum(self.DEFAULT_DIRECTION,
|
|
self.tr('Default direction'),
|
|
list(self.DIRECTIONS.keys()),
|
|
defaultValue=2))
|
|
params.append(QgsProcessingParameterField(self.SPEED_FIELD,
|
|
self.tr('Speed field'),
|
|
None,
|
|
self.INPUT,
|
|
optional=True))
|
|
params.append(QgsProcessingParameterNumber(self.DEFAULT_SPEED,
|
|
self.tr('Default speed (km/h)'),
|
|
QgsProcessingParameterNumber.Double,
|
|
5.0, False, 0, 99999999.99))
|
|
params.append(QgsProcessingParameterNumber(self.TOLERANCE,
|
|
self.tr('Topology tolerance'),
|
|
QgsProcessingParameterNumber.Double,
|
|
0.0, False, 0, 99999999.99))
|
|
params.append(QgsProcessingParameterBoolean(self.INCLUDE_BOUNDS,
|
|
self.tr('Include upper/lower bound points'),
|
|
defaultValue=False))
|
|
|
|
for p in params:
|
|
p.setFlags(p.flags() | QgsProcessingParameterDefinition.FlagAdvanced)
|
|
self.addParameter(p)
|
|
|
|
lines_output = QgsProcessingParameterFeatureSink(self.OUTPUT_LINES,
|
|
self.tr('Service area (lines)'),
|
|
QgsProcessing.TypeVectorLine, optional=True)
|
|
lines_output.setCreateByDefault(True)
|
|
self.addParameter(lines_output)
|
|
|
|
nodes_output = QgsProcessingParameterFeatureSink(self.OUTPUT,
|
|
self.tr('Service area (boundary nodes)'),
|
|
QgsProcessing.TypeVectorPoint, optional=True)
|
|
nodes_output.setCreateByDefault(False)
|
|
self.addParameter(nodes_output)
|
|
|
|
def name(self):
|
|
return 'serviceareafrompoint'
|
|
|
|
def displayName(self):
|
|
return self.tr('Service area (from point)')
|
|
|
|
def processAlgorithm(self, parameters, context, feedback):
|
|
network = self.parameterAsSource(parameters, self.INPUT, context)
|
|
startPoint = self.parameterAsPoint(parameters, self.START_POINT, context, network.sourceCrs())
|
|
strategy = self.parameterAsEnum(parameters, self.STRATEGY, context)
|
|
travelCost = self.parameterAsDouble(parameters, self.TRAVEL_COST, context)
|
|
|
|
directionFieldName = self.parameterAsString(parameters, self.DIRECTION_FIELD, context)
|
|
forwardValue = self.parameterAsString(parameters, self.VALUE_FORWARD, context)
|
|
backwardValue = self.parameterAsString(parameters, self.VALUE_BACKWARD, context)
|
|
bothValue = self.parameterAsString(parameters, self.VALUE_BOTH, context)
|
|
defaultDirection = self.parameterAsEnum(parameters, self.DEFAULT_DIRECTION, context)
|
|
speedFieldName = self.parameterAsString(parameters, self.SPEED_FIELD, context)
|
|
defaultSpeed = self.parameterAsDouble(parameters, self.DEFAULT_SPEED, context)
|
|
tolerance = self.parameterAsDouble(parameters, self.TOLERANCE, context)
|
|
|
|
include_bounds = True # default to true to maintain 3.0 API
|
|
if self.INCLUDE_BOUNDS in parameters:
|
|
include_bounds = self.parameterAsBool(parameters, self.INCLUDE_BOUNDS, context)
|
|
|
|
directionField = -1
|
|
if directionFieldName:
|
|
directionField = network.fields().lookupField(directionFieldName)
|
|
speedField = -1
|
|
if speedFieldName:
|
|
speedField = network.fields().lookupField(speedFieldName)
|
|
|
|
director = QgsVectorLayerDirector(network,
|
|
directionField,
|
|
forwardValue,
|
|
backwardValue,
|
|
bothValue,
|
|
defaultDirection)
|
|
|
|
distUnit = context.project().crs().mapUnits()
|
|
multiplier = QgsUnitTypes.fromUnitToUnitFactor(distUnit, QgsUnitTypes.DistanceMeters)
|
|
if strategy == 0:
|
|
strategy = QgsNetworkDistanceStrategy()
|
|
else:
|
|
strategy = QgsNetworkSpeedStrategy(speedField,
|
|
defaultSpeed,
|
|
multiplier * 1000.0 / 3600.0)
|
|
|
|
director.addStrategy(strategy)
|
|
builder = QgsGraphBuilder(network.sourceCrs(),
|
|
True,
|
|
tolerance)
|
|
feedback.pushInfo(QCoreApplication.translate('ServiceAreaFromPoint', 'Building graph…'))
|
|
snappedPoints = director.makeGraph(builder, [startPoint], feedback)
|
|
|
|
feedback.pushInfo(QCoreApplication.translate('ServiceAreaFromPoint', 'Calculating service area…'))
|
|
graph = builder.graph()
|
|
idxStart = graph.findVertex(snappedPoints[0])
|
|
|
|
tree, cost = QgsGraphAnalyzer.dijkstra(graph, idxStart, 0)
|
|
vertices = set()
|
|
points = []
|
|
lines = []
|
|
|
|
for vertex, start_vertex_cost in enumerate(cost):
|
|
inbound_edge_index = tree[vertex]
|
|
if inbound_edge_index == -1 and vertex != idxStart:
|
|
# unreachable vertex
|
|
continue
|
|
|
|
if start_vertex_cost > travelCost:
|
|
# vertex is too expensive, discard
|
|
continue
|
|
|
|
vertices.add(vertex)
|
|
start_point = graph.vertex(vertex).point()
|
|
|
|
# find all edges coming from this vertex
|
|
for edge_id in graph.vertex(vertex).outgoingEdges():
|
|
edge = graph.edge(edge_id)
|
|
end_vertex_cost = start_vertex_cost + edge.cost(0)
|
|
end_point = graph.vertex(edge.toVertex()).point()
|
|
if end_vertex_cost <= travelCost:
|
|
# end vertex is cheap enough to include
|
|
vertices.add(edge.toVertex())
|
|
lines.append([start_point, end_point])
|
|
else:
|
|
# travelCost sits somewhere on this edge, interpolate position
|
|
interpolated_end_point = QgsGeometryUtils.interpolatePointOnLineByValue(start_point.x(), start_point.y(), start_vertex_cost,
|
|
end_point.x(), end_point.y(), end_vertex_cost, travelCost)
|
|
points.append(interpolated_end_point)
|
|
lines.append([start_point, interpolated_end_point])
|
|
|
|
for i in vertices:
|
|
points.append(graph.vertex(i).point())
|
|
|
|
feedback.pushInfo(QCoreApplication.translate('ServiceAreaFromPoint', 'Writing results…'))
|
|
|
|
fields = QgsFields()
|
|
fields.append(QgsField('type', QVariant.String, '', 254, 0))
|
|
fields.append(QgsField('start', QVariant.String, '', 254, 0))
|
|
|
|
feat = QgsFeature()
|
|
feat.setFields(fields)
|
|
|
|
(point_sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
|
|
fields, QgsWkbTypes.MultiPoint, network.sourceCrs())
|
|
|
|
results = {}
|
|
|
|
if point_sink is not None:
|
|
results[self.OUTPUT] = dest_id
|
|
geomPoints = QgsGeometry.fromMultiPointXY(points)
|
|
feat.setGeometry(geomPoints)
|
|
feat['type'] = 'within'
|
|
feat['start'] = startPoint.toString()
|
|
point_sink.addFeature(feat, QgsFeatureSink.FastInsert)
|
|
|
|
if include_bounds:
|
|
upperBoundary = []
|
|
lowerBoundary = []
|
|
|
|
vertices = []
|
|
for i, v in enumerate(cost):
|
|
if v > travelCost and tree[i] != -1:
|
|
vertexId = graph.edge(tree[i]).fromVertex()
|
|
if cost[vertexId] <= travelCost:
|
|
vertices.append(i)
|
|
|
|
for i in vertices:
|
|
upperBoundary.append(graph.vertex(graph.edge(tree[i]).toVertex()).point())
|
|
lowerBoundary.append(graph.vertex(graph.edge(tree[i]).fromVertex()).point())
|
|
|
|
geomUpper = QgsGeometry.fromMultiPointXY(upperBoundary)
|
|
geomLower = QgsGeometry.fromMultiPointXY(lowerBoundary)
|
|
|
|
feat.setGeometry(geomUpper)
|
|
feat['type'] = 'upper'
|
|
feat['start'] = startPoint.toString()
|
|
point_sink.addFeature(feat, QgsFeatureSink.FastInsert)
|
|
|
|
feat.setGeometry(geomLower)
|
|
feat['type'] = 'lower'
|
|
feat['start'] = startPoint.toString()
|
|
point_sink.addFeature(feat, QgsFeatureSink.FastInsert)
|
|
|
|
(line_sink, line_dest_id) = self.parameterAsSink(parameters, self.OUTPUT_LINES, context,
|
|
fields, QgsWkbTypes.MultiLineString, network.sourceCrs())
|
|
if line_sink is not None:
|
|
results[self.OUTPUT_LINES] = line_dest_id
|
|
geom_lines = QgsGeometry.fromMultiPolylineXY(lines)
|
|
feat.setGeometry(geom_lines)
|
|
feat['type'] = 'lines'
|
|
feat['start'] = startPoint.toString()
|
|
line_sink.addFeature(feat, QgsFeatureSink.FastInsert)
|
|
|
|
return results
|