# -*- coding: utf-8 -*-
"""
***************************************************************************
VoronoiPolygons.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 (QgsFeatureRequest,
QgsFeatureSink,
QgsFeature,
QgsGeometry,
QgsPointXY,
QgsWkbTypes,
QgsProcessing,
QgsProcessingException,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterFeatureSink,
QgsProcessingParameterNumber)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
from . import voronoi
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class VoronoiPolygons(QgisAlgorithm):
INPUT = 'INPUT'
BUFFER = 'BUFFER'
OUTPUT = 'OUTPUT'
def icon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'voronoi.png'))
def group(self):
return self.tr('Vector geometry')
def groupId(self):
return 'vectorgeometry'
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT, self.tr('Input layer'), [QgsProcessing.TypeVectorPoint]))
self.addParameter(QgsProcessingParameterNumber(self.BUFFER, self.tr('Buffer region'), type=QgsProcessingParameterNumber.Double,
minValue=0.0, maxValue=9999999999, defaultValue=0.0))
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Voronoi polygons'), type=QgsProcessing.TypeVectorPolygon))
def name(self):
return 'voronoipolygons'
def displayName(self):
return self.tr('Voronoi polygons')
def processAlgorithm(self, parameters, context, feedback):
source = self.parameterAsSource(parameters, self.INPUT, context)
buf = self.parameterAsDouble(parameters, self.BUFFER, context)
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
source.fields(), QgsWkbTypes.Polygon, source.sourceCrs())
outFeat = QgsFeature()
extent = source.sourceExtent()
extraX = extent.height() * (buf / 100.0)
extraY = extent.width() * (buf / 100.0)
height = extent.height()
width = extent.width()
c = voronoi.Context()
pts = []
ptDict = {}
ptNdx = -1
features = source.getFeatures()
total = 100.0 / source.featureCount() if source.featureCount() else 0
for current, inFeat in enumerate(features):
if feedback.isCanceled():
break
geom = inFeat.geometry()
point = geom.asPoint()
x = point.x() - extent.xMinimum()
y = point.y() - extent.yMinimum()
pts.append((x, y))
ptNdx += 1
ptDict[ptNdx] = inFeat.id()
feedback.setProgress(int(current * total))
if len(pts) < 3:
raise QgsProcessingException(
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[0], i[1], sitenum=j) for (j,
i) in enumerate(uniqueSet)])
voronoi.voronoi(sl, c)
inFeat = QgsFeature()
current = 0
if len(c.polygons) == 0:
raise QgsProcessingException(
self.tr('There were no polygons created.'))
total = 100.0 / len(c.polygons)
for (site, edges) in list(c.polygons.items()):
if feedback.isCanceled():
break
request = QgsFeatureRequest().setFilterFid(ptDict[ids[site]])
inFeat = next(source.getFeatures(request))
lines = self.clip_voronoi(edges, c, width, height, extent, extraX, extraY)
geom = QgsGeometry.fromMultiPointXY(lines)
geom = QgsGeometry(geom.convexHull())
outFeat.setGeometry(geom)
outFeat.setAttributes(inFeat.attributes())
sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
current += 1
feedback.setProgress(int(current * total))
return {self.OUTPUT: dest_id}
def clip_voronoi(self, edges, c, width, height, extent, exX, exY):
"""Clip voronoi function based on code written for Inkscape.
Copyright (C) 2010 Alvin Penner, penner@vaxxine.com
"""
def clip_line(x1, y1, x2, y2, w, h, x, y):
if x1 < 0 - x and x2 < 0 - x:
return [0, 0, 0, 0]
if x1 > w + x and x2 > w + x:
return [0, 0, 0, 0]
if x1 < 0 - x:
y1 = (y1 * x2 - y2 * x1) / (x2 - x1)
x1 = 0 - x
if x2 < 0 - x:
y2 = (y1 * x2 - y2 * x1) / (x2 - x1)
x2 = 0 - x
if x1 > w + x:
y1 = y1 + (w + x - x1) * (y2 - y1) / (x2 - x1)
x1 = w + x
if x2 > w + x:
y2 = y1 + (w + x - x1) * (y2 - y1) / (x2 - x1)
x2 = w + x
if y1 < 0 - y and y2 < 0 - y:
return [0, 0, 0, 0]
if y1 > h + y and y2 > h + y:
return [0, 0, 0, 0]
if x1 == x2 and y1 == y2:
return [0, 0, 0, 0]
if y1 < 0 - y:
x1 = (x1 * y2 - x2 * y1) / (y2 - y1)
y1 = 0 - y
if y2 < 0 - y:
x2 = (x1 * y2 - x2 * y1) / (y2 - y1)
y2 = 0 - y
if y1 > h + y:
x1 = x1 + (h + y - y1) * (x2 - x1) / (y2 - y1)
y1 = h + y
if y2 > h + y:
x2 = x1 + (h + y - y1) * (x2 - x1) / (y2 - y1)
y2 = h + y
return [x1, y1, x2, y2]
lines = []
hasXMin = False
hasYMin = False
hasXMax = False
hasYMax = False
for edge in edges:
if edge[1] >= 0 and edge[2] >= 0:
# Two vertices
[x1, y1, x2, y2] = clip_line(
c.vertices[edge[1]][0],
c.vertices[edge[1]][1],
c.vertices[edge[2]][0],
c.vertices[edge[2]][1],
width,
height,
exX,
exY,
)
elif edge[1] >= 0:
# Only one vertex
if c.lines[edge[0]][1] == 0:
# Vertical line
xtemp = c.lines[edge[0]][2] / c.lines[edge[0]][0]
if c.vertices[edge[1]][1] > (height + exY) / 2:
ytemp = height + exY
else:
ytemp = 0 - exX
else:
xtemp = width + exX
ytemp = (c.lines[edge[0]][2] - (width + exX) *
c.lines[edge[0]][0]) / c.lines[edge[0]][1]
[x1, y1, x2, y2] = clip_line(
c.vertices[edge[1]][0],
c.vertices[edge[1]][1],
xtemp,
ytemp,
width,
height,
exX,
exY,
)
elif edge[2] >= 0:
# Only one vertex
if c.lines[edge[0]][1] == 0:
# Vertical line
xtemp = c.lines[edge[0]][2] / c.lines[edge[0]][0]
if c.vertices[edge[2]][1] > (height + exY) / 2:
ytemp = height + exY
else:
ytemp = 0.0 - exY
else:
xtemp = 0.0 - exX
ytemp = c.lines[edge[0]][2] / c.lines[edge[0]][1]
[x1, y1, x2, y2] = clip_line(
xtemp,
ytemp,
c.vertices[edge[2]][0],
c.vertices[edge[2]][1],
width,
height,
exX,
exY,
)
if x1 or x2 or y1 or y2:
lines.append(QgsPointXY(x1 + extent.xMinimum(),
y1 + extent.yMinimum()))
lines.append(QgsPointXY(x2 + extent.xMinimum(),
y2 + extent.yMinimum()))
if 0 - exX in (x1, x2):
hasXMin = True
if 0 - exY in (y1, y2):
hasYMin = True
if height + exY in (y1, y2):
hasYMax = True
if width + exX in (x1, x2):
hasXMax = True
if hasXMin:
if hasYMax:
lines.append(QgsPointXY(extent.xMinimum() - exX,
height + extent.yMinimum() + exY))
if hasYMin:
lines.append(QgsPointXY(extent.xMinimum() - exX,
extent.yMinimum() - exY))
if hasXMax:
if hasYMax:
lines.append(QgsPointXY(width + extent.xMinimum() + exX,
height + extent.yMinimum() + exY))
if hasYMin:
lines.append(QgsPointXY(width + extent.xMinimum() + exX,
extent.yMinimum() - exY))
return lines