# -*- coding: utf-8 -*- """ *************************************************************************** ExtentFromLayer.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.PyQt.QtCore import QVariant from qgis.core import (QgsField, QgsFeatureSink, QgsPointXY, QgsGeometry, QgsFeature, QgsWkbTypes, QgsProcessingUtils, QgsProcessingParameterFeatureSource, QgsProcessingParameterFeatureSink, QgsProcessingOutputVectorLayer, QgsProcessingParameterBoolean, QgsProcessingParameterDefinition, QgsFields) from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm from processing.core.parameters import ParameterVector from processing.core.parameters import ParameterBoolean 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 ExtentFromLayer(QgisAlgorithm): INPUT_LAYER = 'INPUT_LAYER' BY_FEATURE = 'BY_FEATURE' OUTPUT = 'OUTPUT' def icon(self): return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'layer_extent.png')) def tags(self): return self.tr('extent,envelope,bounds,bounding,boundary,layer').split(',') def group(self): return self.tr('Vector general tools') def __init__(self): super().__init__() self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT_LAYER, self.tr('Input layer'))) self.addParameter(QgsProcessingParameterBoolean(self.BY_FEATURE, self.tr('Calculate extent for each feature separately'), False)) self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Extent'))) self.addOutput(QgsProcessingOutputVectorLayer(self.OUTPUT, self.tr("Extent"), QgsProcessingParameterDefinition.TypeVectorPolygon)) self.source = None self.byFeature = None self.sink = None self.dest_id = None def name(self): return 'polygonfromlayerextent' def displayName(self): return self.tr('Polygon from layer extent') def prepareAlgorithm(self, parameters, context, feedback): self.source = self.parameterAsSource(parameters, self.INPUT_LAYER, context) self.byFeature = self.parameterAsBool(parameters, self.BY_FEATURE, context) fields = QgsFields() fields.append(QgsField('MINX', QVariant.Double)) fields.append(QgsField('MINY', QVariant.Double)) fields.append(QgsField('MAXX', QVariant.Double)) fields.append(QgsField('MAXY', QVariant.Double)) fields.append(QgsField('CNTX', QVariant.Double)) fields.append(QgsField('CNTY', QVariant.Double)) fields.append(QgsField('AREA', QVariant.Double)) fields.append(QgsField('PERIM', QVariant.Double)) fields.append(QgsField('HEIGHT', QVariant.Double)) fields.append(QgsField('WIDTH', QVariant.Double)) (self.sink, self.dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context, fields, QgsWkbTypes.Polygon, self.source.sourceCrs()) return True def processAlgorithm(self, context, feedback): if self.byFeature: self.featureExtent(self.source, context, self.sink, feedback) else: self.layerExtent(self.source, self.sink, feedback) return True def postProcessAlgorithm(self, context, feedback): return {self.OUTPUT: self.dest_id} def layerExtent(self, source, sink, feedback): rect = source.sourceExtent() geometry = QgsGeometry.fromRect(rect) minx = rect.xMinimum() miny = rect.yMinimum() maxx = rect.xMaximum() maxy = rect.yMaximum() height = rect.height() width = rect.width() cntx = minx + width / 2.0 cnty = miny + height / 2.0 area = width * height perim = 2 * width + 2 * height feat = QgsFeature() feat.setGeometry(geometry) attrs = [ minx, miny, maxx, maxy, cntx, cnty, area, perim, height, width, ] feat.setAttributes(attrs) sink.addFeature(feat, QgsFeatureSink.FastInsert) def featureExtent(self, source, context, sink, feedback): features = source.getFeatures() total = 100.0 / source.featureCount() if source.featureCount() else 0 feat = QgsFeature() for current, f in enumerate(features): if feedback.isCanceled(): break rect = f.geometry().boundingBox() minx = rect.xMinimum() miny = rect.yMinimum() maxx = rect.xMaximum() maxy = rect.yMaximum() height = rect.height() width = rect.width() cntx = minx + width / 2.0 cnty = miny + height / 2.0 area = width * height perim = 2 * width + 2 * height rect = [QgsPointXY(minx, miny), QgsPointXY(minx, maxy), QgsPointXY(maxx, maxy), QgsPointXY(maxx, miny), QgsPointXY(minx, miny)] geometry = QgsGeometry().fromPolygon([rect]) feat.setGeometry(geometry) attrs = [ minx, miny, maxx, maxy, cntx, cnty, area, perim, height, width, ] feat.setAttributes(attrs) sink.addFeature(feat, QgsFeatureSink.FastInsert) feedback.setProgress(int(current * total))