2016-03-15 11:46:05 +01:00

154 lines
6.2 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
Dissolve.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 PyQt4.QtGui import QIcon
from qgis.core import QgsFeature, QgsGeometry
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterBoolean
from processing.core.parameters import ParameterTableField
from processing.core.outputs import OutputVector
from processing.tools import vector, dataobjects
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class Dissolve(GeoAlgorithm):
INPUT = 'INPUT'
OUTPUT = 'OUTPUT'
FIELD = 'FIELD'
DISSOLVE_ALL = 'DISSOLVE_ALL'
def getIcon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'dissolve.png'))
def defineCharacteristics(self):
self.name = 'Dissolve'
self.group = 'Vector geometry tools'
self.addParameter(ParameterVector(Dissolve.INPUT,
self.tr('Input layer'),
[ParameterVector.VECTOR_TYPE_POLYGON, ParameterVector.VECTOR_TYPE_LINE]))
self.addParameter(ParameterBoolean(Dissolve.DISSOLVE_ALL,
self.tr('Dissolve all (do not use field)'), True))
self.addParameter(ParameterTableField(Dissolve.FIELD,
self.tr('Unique ID field'), Dissolve.INPUT, optional=True))
self.addOutput(OutputVector(Dissolve.OUTPUT, self.tr('Dissolved')))
def processAlgorithm(self, progress):
useField = not self.getParameterValue(Dissolve.DISSOLVE_ALL)
fieldname = self.getParameterValue(Dissolve.FIELD)
vlayerA = dataobjects.getObjectFromUri(
self.getParameterValue(Dissolve.INPUT))
vproviderA = vlayerA.dataProvider()
fields = vlayerA.fields()
writer = self.getOutputFromName(
Dissolve.OUTPUT).getVectorWriter(fields,
vproviderA.geometryType(),
vproviderA.crs())
outFeat = QgsFeature()
features = vector.features(vlayerA)
total = 100.0 / len(features)
if not useField:
first = True
for current, inFeat in enumerate(features):
progress.setPercentage(int(current * total))
if first:
attrs = inFeat.attributes()
tmpInGeom = QgsGeometry(inFeat.geometry())
if tmpInGeom.isGeosEmpty() or not tmpInGeom.isGeosValid():
continue
outFeat.setGeometry(tmpInGeom)
first = False
else:
tmpInGeom = QgsGeometry(inFeat.geometry())
if tmpInGeom.isGeosEmpty() or not tmpInGeom.isGeosValid():
continue
tmpOutGeom = QgsGeometry(outFeat.geometry())
try:
tmpOutGeom = QgsGeometry(tmpOutGeom.combine(tmpInGeom))
outFeat.setGeometry(tmpOutGeom)
except:
raise GeoAlgorithmExecutionException(
self.tr('Geometry exception while dissolving'))
outFeat.setAttributes(attrs)
writer.addFeature(outFeat)
else:
fieldIdx = vlayerA.fieldNameIndex(fieldname)
unique = vector.getUniqueValues(vlayerA, int(fieldIdx))
nFeat = len(unique)
myDict = {}
attrDict = {}
for item in unique:
myDict[unicode(item).strip()] = []
attrDict[unicode(item).strip()] = None
unique = None
for inFeat in features:
attrs = inFeat.attributes()
tempItem = attrs[fieldIdx]
tmpInGeom = QgsGeometry(inFeat.geometry())
if tmpInGeom.isGeosEmpty() or not tmpInGeom.isGeosValid():
continue
if attrDict[unicode(tempItem).strip()] == None:
# keep attributes of first feature
attrDict[unicode(tempItem).strip()] = attrs
myDict[unicode(tempItem).strip()].append(tmpInGeom)
features = None
nElement = 0
for key, value in myDict.items():
nElement += 1
progress.setPercentage(int(nElement * 100 / nFeat))
for i in range(len(value)):
tmpInGeom = value[i]
if i == 0:
tmpOutGeom = tmpInGeom
else:
try:
tmpOutGeom = QgsGeometry(
tmpOutGeom.combine(tmpInGeom))
except:
raise GeoAlgorithmExecutionException(
self.tr('Geometry exception while dissolving'))
outFeat.setGeometry(tmpOutGeom)
outFeat.setAttributes(attrDict[key])
writer.addFeature(outFeat)
del writer