[processing] add Vector grid algorithm (addresses #5953)

python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py

@@ -16,8 +16,8 @@
 *                                                                         *
 ***************************************************************************
 """
-from processing.script.ScriptUtils import ScriptUtils
-import os
+
+
 
 
 __author__ = 'Victor Olaya'
@@ -28,12 +28,17 @@
 
 __revision__ = '$Format:%H$'
 
+import os
+
 from PyQt4.QtGui import *
 
 from processing.core.AlgorithmProvider import AlgorithmProvider
+from processing.script.ScriptUtils import ScriptUtils
+
 from ftools.RegularPoints import RegularPoints
 from ftools.SymetricalDifference import SymetricalDifference
 from ftools.VectorSplit import VectorSplit
+from ftools.VectorGrid import VectorGrid
 
 from RandomExtract import RandomExtract
 from RandomExtractWithinSubsets import RandomExtractWithinSubsets
@@ -149,7 +154,7 @@ def __init__(self):
                         SelectByLocation(), RandomExtract(),
                         RandomExtractWithinSubsets(), ExtractByLocation(),
                         SpatialJoin(), RegularPoints(), SymetricalDifference(),
-                        VectorSplit(), DeleteColumn(),
+                        VectorSplit(), VectorGrid(), DeleteColumn(),
                         DeleteDuplicateGeometries(), TextToFloat(),
                         ExtractByAttribute(), SelectByAttribute(), Grid(),
                         Gridify(), HubDistance(), HubLines(), Merge(),

python/plugins/processing/algs/qgis/ftools/VectorGrid.py

@@ -0,0 +1,168 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    VectorGrid.py
+    ---------------------
+    Date                 : September 2014
+    Copyright            : (C) 2014 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__ = 'September 2014'
+__copyright__ = '(C) 2014, 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 qgis.utils import iface
+
+from processing.core.GeoAlgorithm import GeoAlgorithm
+from processing.core.parameters import ParameterExtent
+from processing.core.parameters import ParameterNumber
+from processing.core.parameters import ParameterSelection
+from processing.core.outputs import OutputVector
+from processing.tools import vector
+
+
+class VectorGrid(GeoAlgorithm):
+
+    EXTENT = 'EXTENT'
+    STEP_X = 'STEP_X'
+    STEP_Y = 'STEP_Y'
+    TYPE = 'TYPE'
+    OUTPUT = 'OUTPUT'
+
+    TYPES = ['Output grid as polygons',
+             'Output grid as lines'
+            ]
+
+    def defineCharacteristics(self):
+        self.name = 'Vector grid'
+        self.group = 'Vector creation tools'
+        self.addParameter(ParameterExtent(self.EXTENT, 'Grid extent'))
+        self.addParameter(ParameterNumber(self.STEP_X,
+            'X spacing', 0.0, 1000000000.0, 0.0001))
+        self.addParameter(ParameterNumber(self.STEP_Y,
+            'Y spacing', 0.0, 1000000000.0, 0.0001))
+        self.addParameter(ParameterSelection(self.TYPE,
+            'Grid type', self.TYPES))
+
+        self.addOutput(OutputVector(self.OUTPUT, 'Grid'))
+
+    def processAlgorithm(self, progress):
+        extent = self.getParameterValue(self.EXTENT).split(',')
+        xSpace = self.getParameterValue(self.STEP_X)
+        ySpace = self.getParameterValue(self.STEP_Y)
+        polygon = self.getParameterValue(self.TYPE) == 0
+
+        bbox = QgsRectangle(float(extent[0]), float(extent[2]),
+                            float(extent[1]), float(extent[3]))
+
+        mapCRS = iface.mapCanvas().mapSettings().destinationCrs()
+
+        fields = QgsFields()
+        fields.append(QgsField('id', QVariant.Int, '', 10, 0))
+
+        if polygon:
+            fields.append(QgsField('xmin', QVariant.Double, '', 24, 15))
+            fields.append(QgsField('xmax', QVariant.Double, '', 24, 15))
+            fields.append(QgsField('ymin', QVariant.Double, '', 24, 15))
+            fields.append(QgsField('ymax', QVariant.Double, '', 24, 15))
+            fieldCount = 5
+            writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
+                fields, QGis.WKBPolygon, mapCRS)
+        else:
+            fields.append(QgsField('coord', QVariant.Double, '', 24, 15))
+            fieldCount = 2
+            writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
+                fields, QGis.WKBPolygon, mapCRS)
+
+        feat = QgsFeature()
+        feat.initAttributes(fieldCount)
+        feat.setFields(fields)
+        geom = QgsGeometry()
+        idVar = 0
+
+        if not polygon:
+            count = 0
+            count_max = (bbox.yMaximum() - bbox.yMinimum()) / ySpace
+            count_update = count_max * 0.10
+            y = bbox.yMaximum()
+            while y >= bbox.yMinimum():
+                pt1 = QgsPoint(bbox.xMinimum(), y)
+                pt2 = QgsPoint(bbox.xMaximum(), y)
+                line = [pt1, pt2]
+                feat.setGeometry(geom.fromPolyline(line))
+                feat.setAttribute(0, idVar)
+                feat.setAttribute(1, y)
+                writer.addFeature(feat)
+                y = y - ySpace
+                idVar += 1
+                count += 1
+                if int(math.fmod(count, count_update)) == 0:
+                    progress.setPersentage(int(count / count_max * 50))
+
+            progress.setPersentage( 50 )
+            # counters for progressbar - update every 5%
+            count = 0
+            count_max = (bbox.xMaximum() - bbox.xMinimum()) / xSpace
+            count_update = count_max * 0.10
+            x = bbox.xMinimum()
+            while x <= bbox.xMaximum():
+                pt1 = QgsPoint(x, bbox.yMaximum())
+                pt2 = QgsPoint(x, bbox.yMinimum())
+                line = [pt1, pt2]
+                feat.setGeometry(geom.fromPolyline(line))
+                feat.setAttribute(0, idVar)
+                feat.setAttribute(1, x)
+                writer.addFeature(feat)
+                x = x + xOffset
+                idVar += 1
+                count += 1
+                if int(math.fmod(count, count_update)) == 0:
+                    progress.setPercentage(50 + int(count / count_max * 50))
+        else:
+            # counters for progressbar - update every 5%
+            count = 0
+            count_max = (bbox.yMaximum() - bbox.yMinimum()) / ySpace
+            count_update = count_max * 0.05
+            y = bbox.yMaximum()
+            while y >= bbox.yMinimum():
+                x = bbox.xMinimum()
+                while x <= bbox.xMaximum():
+                    pt1 = QgsPoint(x, y)
+                    pt2 = QgsPoint(x + xSpace, y)
+                    pt3 = QgsPoint(x + xSpace, y - ySpace)
+                    pt4 = QgsPoint(x, y - ySpace)
+                    pt5 = QgsPoint(x, y)
+                    polygon = [[pt1, pt2, pt3, pt4, pt5]]
+                    feat.setGeometry(geom.fromPolygon(polygon))
+                    feat.setAttribute(0, idVar)
+                    feat.setAttribute(1, x)
+                    feat.setAttribute(2, x + xSpace)
+                    feat.setAttribute(3, y - ySpace)
+                    feat.setAttribute(4, y)
+                    writer.addFeature(feat)
+                    idVar += 1
+                    x = x + xSpace
+                y = y - ySpace
+                count += 1
+                if int(math.fmod(count, count_update)) == 0:
+                    progress.setPercentage(int(count / count_max * 100))
+
+        del writer