mirror of
https://github.com/qgis/QGIS.git
synced 2025-03-03 00:02:25 -05:00
481 lines
20 KiB
Python
Executable File
481 lines
20 KiB
Python
Executable File
# -*- 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. *
|
|
* *
|
|
***************************************************************************
|
|
"""
|
|
|
|
__authors__ = 'Victor Olaya, Håvard Tveite'
|
|
__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 (QgsApplication,
|
|
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 QgsApplication.getThemeIcon("/algorithms/mAlgorithmVoronoi.svg")
|
|
|
|
def svgIconPath(self):
|
|
return QgsApplication.iconPath("/algorithms/mAlgorithmVoronoi.svg")
|
|
|
|
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 (% of extent)'),
|
|
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)
|
|
if source is None:
|
|
raise QgsProcessingException(
|
|
self.invalidSourceError(parameters, self.INPUT))
|
|
|
|
buf = self.parameterAsDouble(parameters, self.BUFFER, context)
|
|
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT,
|
|
context, source.fields(),
|
|
QgsWkbTypes.Polygon,
|
|
source.sourceCrs())
|
|
if sink is None:
|
|
raise QgsProcessingException(
|
|
self.invalidSinkError(parameters, self.OUTPUT))
|
|
outFeat = QgsFeature()
|
|
extent = source.sourceExtent()
|
|
extraX = extent.width() * (buf / 100.0)
|
|
# Adjust the extent
|
|
extent.setXMinimum(extent.xMinimum() - extraX)
|
|
extent.setXMaximum(extent.xMaximum() + extraX)
|
|
extraY = extent.height() * (buf / 100.0)
|
|
extent.setYMinimum(extent.yMinimum() - extraY)
|
|
extent.setYMaximum(extent.yMaximum() + extraY)
|
|
height = extent.height()
|
|
width = extent.width()
|
|
c = voronoi.Context()
|
|
pts = []
|
|
ptDict = {}
|
|
ptNdx = -1
|
|
# Find the minimum and maximum x and y for the input points
|
|
xmin = width
|
|
xmax = 0
|
|
ymin = height
|
|
ymax = 0
|
|
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()
|
|
if x < xmin:
|
|
xmin = x
|
|
if y < ymin:
|
|
ymin = y
|
|
if x > xmax:
|
|
xmax = x
|
|
if y > ymax:
|
|
ymax = y
|
|
feedback.setProgress(int(current * total))
|
|
if xmin == xmax or ymin == ymax:
|
|
raise QgsProcessingException('The extent of the input points is '
|
|
'not a polygon (all the points are '
|
|
'on a vertical or horizontal line) '
|
|
'- cannot make a Voronoi diagram!')
|
|
xyminmax = [xmin, ymin, xmax, ymax]
|
|
if len(pts) < 3:
|
|
raise QgsProcessingException(
|
|
self.tr('Input file should contain at least 3 points. Choose '
|
|
'another file and try again.'))
|
|
# Eliminate duplicate points
|
|
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)
|
|
if len(c.polygons) == 0:
|
|
raise QgsProcessingException(
|
|
self.tr('There were no polygons created.'))
|
|
|
|
inFeat = QgsFeature()
|
|
current = 0
|
|
total = 100.0 / len(c.polygons)
|
|
# Clip each of the generated "polygons"
|
|
for (site, edges) in list(c.polygons.items()):
|
|
if feedback.isCanceled():
|
|
break
|
|
request = QgsFeatureRequest().setFilterFid(ptDict[ids[site]])
|
|
inFeat = next(source.getFeatures(request))
|
|
boundarypoints = self.clip_voronoi(edges, c, width,
|
|
height, extent,
|
|
inFeat.geometry().asPoint(),
|
|
xyminmax)
|
|
ptgeom = QgsGeometry.fromMultiPointXY(boundarypoints)
|
|
geom = QgsGeometry(ptgeom.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, point, xyminmax):
|
|
"""Clip voronoi function based on code written for Inkscape.
|
|
Copyright (C) 2010 Alvin Penner, penner@vaxxine.com
|
|
Clips one Thiessen polygon (convex polygon) to extent
|
|
"""
|
|
|
|
pt_x = point.x() - extent.xMinimum()
|
|
pt_y = point.y() - extent.yMinimum()
|
|
(xmin, ymin, xmax, ymax) = xyminmax
|
|
|
|
def isclose(a, b, rel_tol=1e-9, abs_tol=0.0):
|
|
return abs(a - b) <= max(rel_tol * max(abs(a), abs(b)), abs_tol)
|
|
|
|
def clip_line(x1, y1, x2, y2, w, h):
|
|
if x1 < 0 and x2 < 0:
|
|
# Completely to the left
|
|
return [0, 0, 0, 0]
|
|
if x1 > w and x2 > w:
|
|
# Completely to the right
|
|
return [0, 0, 0, 0]
|
|
if y1 < 0 and y2 < 0:
|
|
# Completely below
|
|
return [0, 0, 0, 0]
|
|
if y1 > h and y2 > h:
|
|
# Completely above
|
|
return [0, 0, 0, 0]
|
|
# Clip on the left envelope boundary
|
|
if x1 < 0:
|
|
# First point to the left
|
|
y1 = (y1 * x2 - y2 * x1) / (x2 - x1)
|
|
x1 = 0
|
|
if x2 < 0:
|
|
# Last point to the left
|
|
y2 = (y1 * x2 - y2 * x1) / (x2 - x1)
|
|
x2 = 0
|
|
# Clip on the right envelope boundary
|
|
if x1 > w:
|
|
# First point to the right
|
|
y1 = y1 + (w - x1) * (y2 - y1) / (x2 - x1)
|
|
x1 = w
|
|
if x2 > w:
|
|
# Last point to the right
|
|
y2 = y1 + (w - x1) * (y2 - y1) / (x2 - x1)
|
|
x2 = w
|
|
if isclose(x1, x2) and isclose(y1, y2):
|
|
return [0, 0, 0, 0]
|
|
# Clip on the bottom envelope boundary
|
|
if y1 < 0:
|
|
# First point below
|
|
x1 = (x1 * y2 - x2 * y1) / (y2 - y1)
|
|
y1 = 0
|
|
if y2 < 0:
|
|
# Second point below
|
|
x2 = (x1 * y2 - x2 * y1) / (y2 - y1)
|
|
y2 = 0
|
|
# Clip on the top envelope boundary
|
|
if y1 > h:
|
|
# First point above
|
|
x1 = x1 + (h - y1) * (x2 - x1) / (y2 - y1)
|
|
y1 = h
|
|
if y2 > h:
|
|
# Second point above
|
|
x2 = x1 + (h - y1) * (x2 - x1) / (y2 - y1)
|
|
y2 = h
|
|
if isclose(x1, x2) and isclose(y1, y2):
|
|
return [0, 0, 0, 0]
|
|
return [x1, y1, x2, y2]
|
|
|
|
bndpoints = []
|
|
hasXMin = False
|
|
hasYMin = False
|
|
hasXMax = False
|
|
hasYMax = False
|
|
XMinNumber = 0
|
|
XMaxNumber = 0
|
|
YMinNumber = 0
|
|
YMaxNumber = 0
|
|
# The same line may appear twice for collinear input points,
|
|
# so have to remember which lines have contributed
|
|
XMinLine = -1
|
|
XMaxLine = -1
|
|
YMinLine = -1
|
|
YMaxLine = -1
|
|
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
|
|
)
|
|
elif edge[1] >= 0:
|
|
# Only one (left) vertex
|
|
if c.lines[edge[0]][1] == 0:
|
|
# Vertical line
|
|
#xtemp = c.lines[edge[0]][2] / c.lines[edge[0]][0]
|
|
xtemp = c.vertices[edge[1]][0]
|
|
ytemp = 0 - 1
|
|
#if c.vertices[edge[1]][1] > height / 2:
|
|
# ytemp = height
|
|
#else:
|
|
# ytemp = 0
|
|
else:
|
|
# Create an end of the line at the right edge - OK
|
|
xtemp = width
|
|
ytemp = (c.lines[edge[0]][2] - width *
|
|
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
|
|
)
|
|
elif edge[2] >= 0:
|
|
# Only one (right) vertex
|
|
if c.lines[edge[0]][1] == 0:
|
|
# Vertical line
|
|
#xtemp = c.lines[edge[0]][2] / c.lines[edge[0]][0]
|
|
xtemp = c.vertices[edge[2]][0]
|
|
ytemp = height + 1
|
|
#if c.vertices[edge[2]][1] > height / 2:
|
|
# ytemp = height
|
|
#else:
|
|
# ytemp = 0.0
|
|
else:
|
|
# End the line at the left edge - OK
|
|
xtemp = 0.0
|
|
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,
|
|
)
|
|
else:
|
|
# No vertex, only a line
|
|
if c.lines[edge[0]][1] == 0:
|
|
# Vertical line - should not happen
|
|
xtemp = c.lines[edge[0]][2] / c.lines[edge[0]][0]
|
|
ytemp = 0.0
|
|
xend = xtemp
|
|
yend = height
|
|
else:
|
|
# End the line at both edges - ???
|
|
xtemp = 0.0
|
|
ytemp = c.lines[edge[0]][2] / c.lines[edge[0]][1]
|
|
xend = width
|
|
yend = (c.lines[edge[0]][2] - width *
|
|
c.lines[edge[0]][0]) / c.lines[edge[0]][1]
|
|
[x1, y1, x2, y2] = clip_line(
|
|
xtemp,
|
|
ytemp,
|
|
xend,
|
|
yend,
|
|
width,
|
|
height,
|
|
)
|
|
if x1 or x2 or y1 or y2:
|
|
bndpoints.append(QgsPointXY(x1 + extent.xMinimum(),
|
|
y1 + extent.yMinimum()))
|
|
bndpoints.append(QgsPointXY(x2 + extent.xMinimum(),
|
|
y2 + extent.yMinimum()))
|
|
if 0 in (x1, x2):
|
|
hasXMin = True
|
|
if XMinLine != edge[0]:
|
|
XMinNumber = XMinNumber + 1
|
|
XMinLine = edge[0]
|
|
if 0 in (y1, y2):
|
|
hasYMin = True
|
|
if YMinLine != edge[0]:
|
|
YMinNumber = YMinNumber + 1
|
|
YMinLine = edge[0]
|
|
if height in (y1, y2):
|
|
hasYMax = True
|
|
if YMaxLine != edge[0]:
|
|
YMaxNumber = YMaxNumber + 1
|
|
YMaxLine = edge[0]
|
|
if width in (x1, x2):
|
|
hasXMax = True
|
|
if XMaxLine != edge[0]:
|
|
XMaxNumber = XMaxNumber + 1
|
|
XMaxLine = edge[0]
|
|
|
|
# Add auxiliary points for corner cases, if necessary (duplicate
|
|
# points is not a problem - will be ignored later).
|
|
# a) Extreme input points (lowest, leftmost, rightmost, highest)
|
|
# A point can be extreme on both axis
|
|
if pt_x == xmin: # leftmost point
|
|
if XMinNumber == 0:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif XMinNumber == 1:
|
|
if hasYMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif hasYMax:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif pt_x == xmax: # rightmost point
|
|
if XMaxNumber == 0:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif XMaxNumber == 1:
|
|
if hasYMin:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif hasYMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
if pt_y == ymin: # lowest point
|
|
if YMinNumber == 0:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif YMinNumber == 1:
|
|
if hasXMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif hasXMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif pt_y == ymax: # highest point
|
|
if YMaxNumber == 0:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif YMaxNumber == 1:
|
|
if hasXMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif hasXMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
# b) Polygon that covers the x or the y extent:
|
|
if hasYMin and hasYMax:
|
|
if YMaxNumber > 1:
|
|
if hasXMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif hasXMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif YMinNumber > 1:
|
|
if hasXMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif hasXMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif hasXMin and hasXMax:
|
|
if XMaxNumber > 1:
|
|
if hasYMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif hasYMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
elif XMinNumber > 1:
|
|
if hasYMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
elif hasYMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
# c) Simple corners:
|
|
if XMinNumber == 1 and YMinNumber == 1 and not hasXMax and not hasYMax:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
if XMinNumber == 1 and YMaxNumber == 1 and not hasXMax and not hasYMin:
|
|
bndpoints.append(QgsPointXY(extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
if XMaxNumber == 1 and YMinNumber == 1 and not hasXMin and not hasYMax:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
extent.yMinimum()))
|
|
if XMaxNumber == 1 and YMaxNumber == 1 and not hasXMin and not hasYMin:
|
|
bndpoints.append(QgsPointXY(width + extent.xMinimum(),
|
|
height + extent.yMinimum()))
|
|
return bndpoints
|