# -*- coding: utf-8 -*- """ *************************************************************************** Delaunay.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.PyQt.QtCore import QVariant from qgis.core import QGis, QgsField, QgsFeatureRequest, QgsFeature, QgsGeometry, QgsPoint from processing.core.GeoAlgorithm import GeoAlgorithm from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException from processing.tools import dataobjects, vector from processing.core.parameters import ParameterVector from processing.core.outputs import OutputVector from . import voronoi pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0] class Delaunay(GeoAlgorithm): INPUT = 'INPUT' OUTPUT = 'OUTPUT' def getIcon(self): return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'delaunay.png')) def defineCharacteristics(self): self.name, self.i18n_name = self.trAlgorithm('Delaunay triangulation') self.group, self.i18n_group = self.trAlgorithm('Vector geometry tools') self.addParameter(ParameterVector(self.INPUT, self.tr('Input layer'), [ParameterVector.VECTOR_TYPE_POINT])) self.addOutput(OutputVector(self.OUTPUT, self.tr('Delaunay triangulation'))) def processAlgorithm(self, progress): layer = dataobjects.getObjectFromUri( self.getParameterValue(self.INPUT)) fields = [QgsField('POINTA', QVariant.Double, '', 24, 15), QgsField('POINTB', QVariant.Double, '', 24, 15), QgsField('POINTC', QVariant.Double, '', 24, 15)] writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fields, QGis.WKBPolygon, layer.crs()) pts = [] ptDict = {} ptNdx = -1 c = voronoi.Context() features = vector.features(layer) total = 100.0 / len(features) for current, inFeat in enumerate(features): geom = QgsGeometry(inFeat.geometry()) point = geom.asPoint() x = point.x() y = point.y() pts.append((x, y)) ptNdx += 1 ptDict[ptNdx] = inFeat.id() progress.setPercentage(int(current * total)) if len(pts) < 3: raise GeoAlgorithmExecutionException( self.tr('Input file should contain at least 3 points. Choose ' 'another file and try again.')) uniqueSet = set(item for item in pts) ids = [pts.index(item) for item in uniqueSet] sl = voronoi.SiteList([voronoi.Site(*i) for i in uniqueSet]) c.triangulate = True voronoi.voronoi(sl, c) triangles = c.triangles feat = QgsFeature() total = 100.0 / len(triangles) for current, triangle in enumerate(triangles): indicies = list(triangle) indicies.append(indicies[0]) polygon = [] attrs = [] step = 0 for index in indicies: request = QgsFeatureRequest().setFilterFid(ptDict[ids[index]]) inFeat = layer.getFeatures(request).next() geom = QgsGeometry(inFeat.geometry()) point = QgsPoint(geom.asPoint()) polygon.append(point) if step <= 3: attrs.append(ids[index]) step += 1 feat.setAttributes(attrs) geometry = QgsGeometry().fromPolygon([polygon]) feat.setGeometry(geometry) writer.addFeature(feat) progress.setPercentage(int(current * total)) del writer