[processing] add points displacement algorithm

Author: alexbruy

python/plugins/processing/algs/QGISAlgorithmProvider.py

@@ -86,6 +86,8 @@
 from processing.algs.CreateConstantRaster import CreateConstantRaster
 from processing.algs.PointsLayerFromTable import PointsLayerFromTable
 
+from processing.algs.PointsDisplacement import PointsDisplacement
+
 #from processing.algs.VectorLayerHistogram import VectorLayerHistogram
 #from processing.algs.VectorLayerScatterplot import VectorLayerScatterplot
 #from processing.algs.MeanAndStdDevPlot import MeanAndStdDevPlot
@@ -134,10 +136,12 @@ def __init__(self):
                         PointsLayerFromTable(), StatisticsByCategories(), Polygonize(),
                         # ------ raster ------
                         #CreateConstantRaster(),
-                        RasterLayerStatistics()
+                        RasterLayerStatistics(),
                         # ------ graphics ------
                         #VectorLayerHistogram(), VectorLayerScatterplot(), RasterLayerHistogram(),
                         #MeanAndStdDevPlot(), BarPlot(), PolarPlot()
+                        # ------ vector ------
+                        PointsDisplacement()
                         ]
 
     def initializeSettings(self):

python/plugins/sextante/algs/PointsDisplacement.py

@@ -0,0 +1,121 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    PointsDisplacement.py
+    ---------------------
+    Date                 : July 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__ = 'July 2013'
+__copyright__ = '(C) 2013, Alexander Bruy'
+# This will get replaced with a git SHA1 when you do a git archive
+__revision__ = '$Format:%H$'
+
+import math
+
+from PyQt4.QtCore import *
+
+from qgis.core import *
+
+from sextante.core.GeoAlgorithm import GeoAlgorithm
+from sextante.core.QGisLayers import QGisLayers
+
+from sextante.parameters.ParameterVector import ParameterVector
+from sextante.parameters.ParameterNumber import ParameterNumber
+from sextante.parameters.ParameterBoolean import ParameterBoolean
+from sextante.outputs.OutputVector import OutputVector
+
+class PointsDisplacement(GeoAlgorithm):
+
+    INPUT_LAYER = "INPUT_LAYER"
+    DISTANCE = "DISTANCE"
+    HORIZONTAL = "HORIZONTAL"
+    OUTPUT_LAYER = "OUTPUT_LAYER"
+
+    def defineCharacteristics(self):
+        self.name = "Points displacement"
+        self.group = "Vector geometry tools"
+
+        self.addParameter(ParameterVector(self.INPUT_LAYER, "Input layer", ParameterVector.VECTOR_TYPE_POINT))
+        self.addParameter(ParameterNumber(self.DISTANCE, "Displacement distance", 0.00001, 999999999.999990, 0.00015))
+        self.addParameter(ParameterBoolean(self.HORIZONTAL, "Horizontal distribution for two point case"))
+        self.addOutput(OutputVector(self.OUTPUT_LAYER, "Output layer"))
+
+    def processAlgorithm(self, progress):
+        radius = self.getParameterValue(self.DISTANCE)
+        horizontal = self.getParameterValue(self.HORIZONTAL)
+        output = self.getOutputFromName(self.OUTPUT_LAYER)
+
+        layer = QGisLayers.getObjectFromUri(self.getParameterValue(self.INPUT_LAYER))
+
+        provider = layer.dataProvider()
+        writer = output.getVectorWriter(provider.fields(), provider.geometryType(), provider.crs())
+
+        features = QGisLayers.features(layer)
+
+        current = 0
+        total = 100.0 / len(features)
+
+        duplicates = dict()
+        for f in features:
+            wkt = f.geometry().exportToWkt()
+            if wkt not in duplicates:
+                duplicates[wkt] = [f.id()]
+            else:
+                duplicates[wkt].extend([f.id()])
+
+            current += 1
+            progress.setPercentage(int(current * total))
+
+        current = 0
+        total = 100.0 / len(duplicates)
+        progress.setPercentage(0)
+
+        fullPerimeter = 2 * math.pi
+
+        request = QgsFeatureRequest()
+        for geom, fids in duplicates.iteritems():
+            count = len(fids)
+            if count == 1:
+                f = layer.getFeatures(request.setFilterFid(fids[0])).next()
+                writer.addFeature(f)
+            else:
+                angleStep = fullPerimeter / count
+                if count == 2 and horizontal:
+                    currentAngle = math.pi / 2
+                else:
+                    currentAngle = 0
+
+                old_point = QgsGeometry.fromWkt(geom).asPoint()
+                for fid in fids:
+                    sinusCurrentAngle = math.sin(currentAngle)
+                    cosinusCurrentAngle = math.cos(currentAngle)
+                    dx = radius * sinusCurrentAngle
+                    dy = radius * cosinusCurrentAngle
+
+                    f = layer.getFeatures(request.setFilterFid(fid)).next()
+
+                    new_point = QgsPoint(old_point.x() + dx, old_point.y() + dy)
+                    out_feature = QgsFeature()
+                    out_feature.setGeometry(QgsGeometry.fromPoint(new_point))
+                    out_feature.setAttributes(f.attributes())
+
+                    writer.addFeature(out_feature)
+                    currentAngle += angleStep
+
+            current += 1
+            progress.setPercentage(int(current * total))
+
+        del writer