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			111 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			111 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| # -*- coding: utf-8 -*-
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| 
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| """
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| ***************************************************************************
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|     SimplifyGeometries.py
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|     ---------------------
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|     Date                 : August 2012
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|     Copyright            : (C) 2012 by Victor Olaya
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|     Email                : volayaf at gmail dot com
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| ***************************************************************************
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| *                                                                         *
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| *   This program is free software; you can redistribute it and/or modify  *
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| *   it under the terms of the GNU General Public License as published by  *
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| *   the Free Software Foundation; either version 2 of the License, or     *
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| *   (at your option) any later version.                                   *
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| *                                                                         *
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| ***************************************************************************
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| """
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| 
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| __author__ = 'Victor Olaya'
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| __date__ = 'August 2012'
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| __copyright__ = '(C) 2012, Victor Olaya'
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| 
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| # This will get replaced with a git SHA1 when you do a git archive
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| 
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| __revision__ = '$Format:%H$'
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| 
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| import os
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| 
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| from qgis.PyQt.QtGui import QIcon
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| 
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| from qgis.core import Qgis, QgsFeature, QgsGeometry, QgsWkbTypes, QgsMapToPixelSimplifier
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| 
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| from processing.core.GeoAlgorithm import GeoAlgorithm
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| from processing.core.ProcessingLog import ProcessingLog
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| from processing.core.parameters import ParameterVector
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| from processing.core.parameters import ParameterNumber
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| from processing.core.parameters import ParameterSelection
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| from processing.core.outputs import OutputVector
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| from processing.tools import dataobjects, vector
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| 
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| pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
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| 
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| 
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| class SimplifyGeometries(GeoAlgorithm):
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| 
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|     INPUT = 'INPUT'
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|     TOLERANCE = 'TOLERANCE'
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|     OUTPUT = 'OUTPUT'
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|     METHOD = 'METHOD'
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| 
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|     def getIcon(self):
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|         return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'simplify.png'))
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| 
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|     def defineCharacteristics(self):
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|         self.name, self.i18n_name = self.trAlgorithm('Simplify geometries')
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|         self.group, self.i18n_group = self.trAlgorithm('Vector geometry tools')
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| 
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|         self.addParameter(ParameterVector(self.INPUT,
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|                                           self.tr('Input layer'),
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|                                           [dataobjects.TYPE_VECTOR_POLYGON, dataobjects.TYPE_VECTOR_LINE]))
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|         self.methods = [self.tr('Distance (Douglas-Peucker)'),
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|                         'Snap to grid',
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|                         'Area (Visvalingam)']
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|         self.addParameter(ParameterSelection(
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|             self.METHOD,
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|             self.tr('Simplification method'),
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|             self.methods, default=0))
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|         self.addParameter(ParameterNumber(self.TOLERANCE,
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|                                           self.tr('Tolerance'), 0.0, 10000000.0, 1.0))
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| 
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|         self.addOutput(OutputVector(self.OUTPUT, self.tr('Simplified')))
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| 
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|     def processAlgorithm(self, progress):
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|         layer = dataobjects.getObjectFromUri(self.getParameterValue(self.INPUT))
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|         tolerance = self.getParameterValue(self.TOLERANCE)
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|         method = self.getParameterValue(self.METHOD)
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| 
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|         pointsBefore = 0
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|         pointsAfter = 0
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| 
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|         writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
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|             layer.fields().toList(), layer.wkbType(), layer.crs())
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| 
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|         features = vector.features(layer)
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|         total = 100.0 / len(features)
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| 
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|         if method != 0:
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|             simplifier = QgsMapToPixelSimplifier(QgsMapToPixelSimplifier.SimplifyGeometry, tolerance, method)
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| 
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|         for current, input_feature in enumerate(features):
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|             out_feature = input_feature
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|             if input_feature.geometry():
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|                 input_geometry = input_feature.geometry()
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|                 pointsBefore += input_geometry.geometry().nCoordinates()
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| 
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|                 if method == 0: # distance
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|                     output_geometry = input_geometry.simplify(tolerance)
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|                 else:
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|                     output_geometry = simplifier.simplify(input_geometry)
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| 
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|                 pointsAfter += output_geometry.geometry().nCoordinates()
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|                 out_feature.setGeometry(output_geometry)
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|             writer.addFeature(out_feature)
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|             progress.setPercentage(int(current * total))
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| 
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|         del writer
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| 
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|         ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
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|                                self.tr('Simplify: Input geometries have been simplified from %s to %s points' % (pointsBefore, pointsAfter)))
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