QGIS/python/plugins/processing/algs/qgis/RegularPoints.py

147 lines
5.6 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
RegularPoints.py
---------------------
Date : September 2014
Copyright : (C) 2014 by Alexander Bruy
Email : alexander dot bruy 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. *
* *
***************************************************************************
"""
from builtins import str
__author__ = 'Alexander Bruy'
__date__ = 'September 2014'
__copyright__ = '(C) 2014, Alexander Bruy'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
import os
from random import seed, uniform
from math import sqrt
from qgis.PyQt.QtGui import QIcon
from qgis.PyQt.QtCore import QVariant
from qgis.core import (QgsRectangle, QgsFields, QgsField, QgsFeature, QgsWkbTypes,
QgsGeometry, QgsPoint, QgsCoordinateReferenceSystem)
from qgis.utils import iface
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterExtent
from processing.core.parameters import ParameterNumber
from processing.core.parameters import ParameterBoolean
from processing.core.parameters import ParameterCrs
from processing.core.outputs import OutputVector
from processing.tools import dataobjects
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class RegularPoints(GeoAlgorithm):
EXTENT = 'EXTENT'
SPACING = 'SPACING'
INSET = 'INSET'
RANDOMIZE = 'RANDOMIZE'
IS_SPACING = 'IS_SPACING'
OUTPUT = 'OUTPUT'
CRS = 'CRS'
def icon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'regular_points.png'))
def group(self):
return self.tr('Vector creation tools')
def name(self):
return 'regularpoints'
def displayName(self):
return self.tr('Regular points')
def defineCharacteristics(self):
self.addParameter(ParameterExtent(self.EXTENT,
self.tr('Input extent'), optional=False))
self.addParameter(ParameterNumber(self.SPACING,
self.tr('Point spacing/count'), 100, 999999999.999999999, 100))
self.addParameter(ParameterNumber(self.INSET,
self.tr('Initial inset from corner (LH side)'), 0.0, 9999.9999, 0.0))
self.addParameter(ParameterBoolean(self.RANDOMIZE,
self.tr('Apply random offset to point spacing'), False))
self.addParameter(ParameterBoolean(self.IS_SPACING,
self.tr('Use point spacing'), True))
self.addParameter(ParameterCrs(self.CRS,
self.tr('Output layer CRS'), 'ProjectCrs'))
self.addOutput(OutputVector(self.OUTPUT, self.tr('Regular points'), datatype=[dataobjects.TYPE_VECTOR_POINT]))
def processAlgorithm(self, context, feedback):
extent = str(self.getParameterValue(self.EXTENT)).split(',')
spacing = float(self.getParameterValue(self.SPACING))
inset = float(self.getParameterValue(self.INSET))
randomize = self.getParameterValue(self.RANDOMIZE)
isSpacing = self.getParameterValue(self.IS_SPACING)
crsId = self.getParameterValue(self.CRS)
crs = QgsCoordinateReferenceSystem()
crs.createFromUserInput(crsId)
extent = QgsRectangle(float(extent[0]), float(extent[2]),
float(extent[1]), float(extent[3]))
fields = QgsFields()
fields.append(QgsField('id', QVariant.Int, '', 10, 0))
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
fields, QgsWkbTypes.Point, crs)
if randomize:
seed()
area = extent.width() * extent.height()
if isSpacing:
pSpacing = spacing
else:
pSpacing = sqrt(area / spacing)
f = QgsFeature()
f.initAttributes(1)
f.setFields(fields)
count = 0
total = 100.0 / (area / pSpacing)
y = extent.yMaximum() - inset
extent_geom = QgsGeometry.fromRect(extent)
extent_engine = QgsGeometry.createGeometryEngine(extent_geom.geometry())
extent_engine.prepareGeometry()
while y >= extent.yMinimum():
x = extent.xMinimum() + inset
while x <= extent.xMaximum():
if randomize:
geom = QgsGeometry().fromPoint(QgsPoint(
uniform(x - (pSpacing / 2.0), x + (pSpacing / 2.0)),
uniform(y - (pSpacing / 2.0), y + (pSpacing / 2.0))))
else:
geom = QgsGeometry().fromPoint(QgsPoint(x, y))
if extent_engine.intersects(geom.geometry()):
f.setAttribute('id', count)
f.setGeometry(geom)
writer.addFeature(f)
x += pSpacing
count += 1
feedback.setProgress(int(count * total))
y = y - pSpacing
del writer