140 lines
5.6 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
SumLines.py
---------------------
Date : August 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. *
* *
***************************************************************************
"""
__author__ = 'Victor Olaya'
__date__ = 'August 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.PyQt.QtGui import QIcon
from qgis.core import QgsFeature, QgsFeatureSink, QgsGeometry, QgsFeatureRequest, QgsDistanceArea, QgsProcessingUtils
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterString
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 SumLines(QgisAlgorithm):
LINES = 'LINES'
POLYGONS = 'POLYGONS'
LEN_FIELD = 'LEN_FIELD'
COUNT_FIELD = 'COUNT_FIELD'
OUTPUT = 'OUTPUT'
def icon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'sum_lines.png'))
def group(self):
return self.tr('Vector analysis tools')
def __init__(self):
super().__init__()
self.addParameter(ParameterVector(self.LINES,
self.tr('Lines'), [dataobjects.TYPE_VECTOR_LINE]))
self.addParameter(ParameterVector(self.POLYGONS,
self.tr('Polygons'), [dataobjects.TYPE_VECTOR_POLYGON]))
self.addParameter(ParameterString(self.LEN_FIELD,
self.tr('Lines length field name', 'LENGTH')))
self.addParameter(ParameterString(self.COUNT_FIELD,
self.tr('Lines count field name', 'COUNT')))
self.addOutput(OutputVector(self.OUTPUT, self.tr('Line length'), datatype=[dataobjects.TYPE_VECTOR_POLYGON]))
def name(self):
return 'sumlinelengths'
def displayName(self):
return self.tr('Sum line lengths')
def processAlgorithm(self, parameters, context, feedback):
lineLayer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.LINES), context)
polyLayer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.POLYGONS), context)
lengthFieldName = self.getParameterValue(self.LEN_FIELD)
countFieldName = self.getParameterValue(self.COUNT_FIELD)
(idxLength, fieldList) = vector.findOrCreateField(polyLayer,
polyLayer.fields(), lengthFieldName)
(idxCount, fieldList) = vector.findOrCreateField(polyLayer, fieldList,
countFieldName)
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fieldList, polyLayer.wkbType(),
polyLayer.crs(), context)
spatialIndex = QgsProcessingUtils.createSpatialIndex(lineLayer, context)
ftLine = QgsFeature()
ftPoly = QgsFeature()
outFeat = QgsFeature()
inGeom = QgsGeometry()
outGeom = QgsGeometry()
distArea = QgsDistanceArea()
features = QgsProcessingUtils.getFeatures(polyLayer, context)
total = 100.0 / polyLayer.featureCount() if polyLayer.featureCount() else 0
hasIntersections = False
for current, ftPoly in enumerate(features):
inGeom = ftPoly.geometry()
attrs = ftPoly.attributes()
count = 0
length = 0
hasIntersections = False
lines = spatialIndex.intersects(inGeom.boundingBox())
engine = None
if len(lines) > 0:
hasIntersections = True
# use prepared geometries for faster intersection tests
engine = QgsGeometry.createGeometryEngine(inGeom.geometry())
engine.prepareGeometry()
if hasIntersections:
request = QgsFeatureRequest().setFilterFids(lines).setSubsetOfAttributes([])
for ftLine in lineLayer.getFeatures(request):
tmpGeom = ftLine.geometry()
if engine.intersects(tmpGeom.geometry()):
outGeom = inGeom.intersection(tmpGeom)
length += distArea.measureLength(outGeom)
count += 1
outFeat.setGeometry(inGeom)
if idxLength == len(attrs):
attrs.append(length)
else:
attrs[idxLength] = length
if idxCount == len(attrs):
attrs.append(count)
else:
attrs[idxCount] = count
outFeat.setAttributes(attrs)
writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
feedback.setProgress(int(current * total))
del writer