mirror of
https://github.com/qgis/QGIS.git
synced 2025-03-03 00:02:25 -05:00
152 lines
5.7 KiB
Python
152 lines
5.7 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
"""
|
|
***************************************************************************
|
|
PointsFromPolygons.py
|
|
---------------------
|
|
Date : August 2013
|
|
Copyright : (C) 2013 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. *
|
|
* *
|
|
***************************************************************************
|
|
"""
|
|
|
|
__author__ = 'Alexander Bruy'
|
|
__date__ = 'August 2013'
|
|
__copyright__ = '(C) 2013, Alexander Bruy'
|
|
|
|
# This will get replaced with a git SHA1 when you do a git archive
|
|
|
|
__revision__ = '$Format:%H$'
|
|
|
|
from osgeo import gdal
|
|
from qgis.core import (QgsFeatureRequest,
|
|
QgsFields,
|
|
QgsField,
|
|
QgsFeature,
|
|
QgsFeatureSink,
|
|
QgsGeometry,
|
|
QgsWkbTypes,
|
|
QgsPoint,
|
|
QgsProcessing,
|
|
QgsProcessingException,
|
|
QgsProcessingParameterRasterLayer,
|
|
QgsProcessingParameterFeatureSource,
|
|
QgsProcessingParameterFeatureSink)
|
|
from qgis.PyQt.QtCore import QVariant
|
|
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
|
|
from processing.tools import raster
|
|
|
|
|
|
class PointsFromPolygons(QgisAlgorithm):
|
|
|
|
INPUT_RASTER = 'INPUT_RASTER'
|
|
INPUT_VECTOR = 'INPUT_VECTOR'
|
|
OUTPUT = 'OUTPUT'
|
|
|
|
def group(self):
|
|
return self.tr('Vector creation')
|
|
|
|
def groupId(self):
|
|
return 'vectorcreation'
|
|
|
|
def __init__(self):
|
|
super().__init__()
|
|
|
|
def initAlgorithm(self, config=None):
|
|
self.addParameter(QgsProcessingParameterRasterLayer(self.INPUT_RASTER,
|
|
self.tr('Raster layer')))
|
|
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT_VECTOR,
|
|
self.tr('Vector layer'), [QgsProcessing.TypeVectorPolygon]))
|
|
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Points inside polygons'), QgsProcessing.TypeVectorPoint))
|
|
|
|
def name(self):
|
|
return 'generatepointspixelcentroidsinsidepolygons'
|
|
|
|
def displayName(self):
|
|
return self.tr('Generate points (pixel centroids) inside polygons')
|
|
|
|
def processAlgorithm(self, parameters, context, feedback):
|
|
source = self.parameterAsSource(parameters, self.INPUT_VECTOR, context)
|
|
if source is None:
|
|
raise QgsProcessingException(self.invalidSourceError(parameters, self.INPUT_VECTOR))
|
|
|
|
raster_layer = self.parameterAsRasterLayer(parameters, self.INPUT_RASTER, context)
|
|
rasterPath = raster_layer.source()
|
|
|
|
rasterDS = gdal.Open(rasterPath, gdal.GA_ReadOnly)
|
|
geoTransform = rasterDS.GetGeoTransform()
|
|
|
|
fields = QgsFields()
|
|
fields.append(QgsField('id', QVariant.Int, '', 10, 0))
|
|
fields.append(QgsField('poly_id', QVariant.Int, '', 10, 0))
|
|
fields.append(QgsField('point_id', QVariant.Int, '', 10, 0))
|
|
|
|
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
|
|
fields, QgsWkbTypes.Point, raster_layer.crs())
|
|
if sink is None:
|
|
raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))
|
|
|
|
outFeature = QgsFeature()
|
|
outFeature.setFields(fields)
|
|
|
|
fid = 0
|
|
polyId = 0
|
|
pointId = 0
|
|
|
|
features = source.getFeatures(QgsFeatureRequest().setDestinationCrs(raster_layer.crs(), context.transformContext()))
|
|
total = 100.0 / source.featureCount() if source.featureCount() else 0
|
|
for current, f in enumerate(features):
|
|
if feedback.isCanceled():
|
|
break
|
|
|
|
if not f.hasGeometry():
|
|
continue
|
|
|
|
geom = f.geometry()
|
|
bbox = geom.boundingBox()
|
|
|
|
xMin = bbox.xMinimum()
|
|
xMax = bbox.xMaximum()
|
|
yMin = bbox.yMinimum()
|
|
yMax = bbox.yMaximum()
|
|
|
|
(startRow, startColumn) = raster.mapToPixel(xMin, yMax, geoTransform)
|
|
(endRow, endColumn) = raster.mapToPixel(xMax, yMin, geoTransform)
|
|
|
|
# use prepared geometries for faster intersection tests
|
|
engine = QgsGeometry.createGeometryEngine(geom.constGet())
|
|
engine.prepareGeometry()
|
|
|
|
for row in range(startRow, endRow + 1):
|
|
for col in range(startColumn, endColumn + 1):
|
|
if feedback.isCanceled():
|
|
break
|
|
|
|
(x, y) = raster.pixelToMap(row, col, geoTransform)
|
|
point = QgsPoint(x, y)
|
|
|
|
if engine.contains(point):
|
|
outFeature.setGeometry(QgsGeometry(point))
|
|
outFeature['id'] = fid
|
|
outFeature['poly_id'] = polyId
|
|
outFeature['point_id'] = pointId
|
|
|
|
fid += 1
|
|
pointId += 1
|
|
|
|
sink.addFeature(outFeature, QgsFeatureSink.FastInsert)
|
|
|
|
pointId = 0
|
|
polyId += 1
|
|
|
|
feedback.setProgress(int(current * total))
|
|
|
|
return {self.OUTPUT: dest_id}
|