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

164 lines
4.7 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
RasterSampling.py
-----------------------
Date : July 2018
Copyright : (C) 2018 by Matteo Ghetta
Email : matteo dot ghetta 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__ = 'Matteo Ghetta'
__date__ = 'July 2018'
__copyright__ = '(C) 2018, Matteo Ghetta'
# 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 (QgsApplication,
QgsField,
QgsFeatureSink,
QgsRaster,
QgsProcessing,
QgsProcessingParameterMultipleLayers,
QgsFields,
QgsProcessingUtils,
QgsProcessingException,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterFeatureSink)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
class RasterSampling(QgisAlgorithm):
INPUT = 'INPUT'
RASTERCOPY = 'RASTERCOPY'
OUTPUT = 'OUTPUT'
def name(self):
return 'rastersampling'
def displayName(self):
return self.tr('Sample Raster Values')
def group(self):
return self.tr('Raster analysis')
def groupId(self):
return 'rasteranalysis'
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(
QgsProcessingParameterFeatureSource(
self.INPUT,
self.tr('Input Point Layer'),
[QgsProcessing.TypeVectorPoint]
)
)
self.addParameter(
QgsProcessingParameterMultipleLayers(
self.RASTERCOPY,
self.tr('Raster Layer to sample'),
QgsProcessing.TypeRaster
)
)
self.addParameter(
QgsProcessingParameterFeatureSink(
self.OUTPUT,
self.tr('Sampled Points')
)
)
def processAlgorithm(self, parameters, context, feedback):
source = self.parameterAsSource(
parameters,
self.INPUT,
context
)
sampled_rasters = self.parameterAsLayerList(
parameters,
self.RASTERCOPY,
context
)
if source is None:
raise QgsProcessingException(self.invalidSourceError(parameters, self.INPUT))
source_fields = source.fields()
raster_fields = QgsFields()
# append field to vector as rasterName_bandCount
for i in sampled_rasters:
for b in range(i.bandCount()):
raster_fields.append(QgsField(i.name() + str('_{}'.format(b+1)), QVariant.Double))
# combine all the vector fields
out_fields = QgsProcessingUtils.combineFields(source_fields, raster_fields)
(sink, dest_id) = self.parameterAsSink(
parameters,
self.OUTPUT,
context,
out_fields,
source.wkbType(),
source.sourceCrs()
)
if sink is None:
raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))
total = 100.0 / source.featureCount() if source.featureCount() else 0
features = source.getFeatures()
for n, i in enumerate(source.getFeatures()):
for rr in sampled_rasters:
attrs = i.attributes()
if rr.bandCount() >1:
for b in range(rr.bandCount()):
attrs.append(rr.dataProvider().identify(i.geometry().asPoint(),
QgsRaster.IdentifyFormatValue).results()[b+1])
attrs.append(rr.dataProvider().identify(i.geometry().asPoint(), QgsRaster.IdentifyFormatValue).results()[1])
i.setAttributes(attrs)
sink.addFeature(i, QgsFeatureSink.FastInsert)
feedback.setProgress(int(n * total))
return {self.OUTPUT: dest_id}