[processing] add GDAL Contour algorithm

python/plugins/processing/gdal/GdalOgrAlgorithmProvider.py

@@ -45,6 +45,7 @@
 from processing.gdal.gdaladdo import gdaladdo
 from processing.gdal.ClipByExtent import ClipByExtent
 from processing.gdal.ClipByMask import ClipByMask
+from processing.gdal.contour import contour
 
 from processing.gdal.ogr2ogr import Ogr2Ogr
 from processing.gdal.ogrinfo import OgrInfo
@@ -94,6 +95,7 @@ def createAlgsList(self):
         self.preloadedAlgs = [nearblack(), information(), warp(), translate(),
                               rgb2pct(), pct2rgb(), merge(), polygonize(),
                               gdaladdo(), ClipByExtent(), ClipByMask(),
+                              contour(),
                               OgrInfo(), Ogr2Ogr(), OgrSql()]
 
         #And then we add those that are created as python scripts

python/plugins/processing/gdal/contour.py

@@ -0,0 +1,80 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    contour.py
+    ---------------------
+    Date                 : September 2013
+    Copyright            : (C) 2013 by Alexander Bruy
+    Email                : alexander 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 2013'
+__copyright__ = '(C) 2013, Alexander Bruy'
+# This will get replaced with a git SHA1 when you do a git archive
+__revision__ = '$Format:%H$'
+
+import os
+from PyQt4 import QtGui
+from qgis.core import *
+
+from processing.core.GeoAlgorithm import GeoAlgorithm
+
+from processing.parameters.ParameterRaster import ParameterRaster
+from processing.parameters.ParameterNumber import ParameterNumber
+from processing.parameters.ParameterString import ParameterString
+
+from processing.outputs.OutputVector import OutputVector
+
+from processing.gdal.GdalUtils import GdalUtils
+
+class contour(GeoAlgorithm):
+
+    INPUT_RASTER = "INPUT_RASTER"
+    OUTPUT_VECTOR = "OUTPUT_VECTOR"
+    INTERVAL = "INTERVAL"
+    FIELD_NAME = "FIELD_NAME"
+    EXTRA = "EXTRA"
+
+    def getIcon(self):
+        filepath = os.path.dirname(__file__) + "/icons/contour.png"
+        return QtGui.QIcon(filepath)
+
+    def defineCharacteristics(self):
+        self.name = "Contour"
+        self.group = "[GDAL] Extraction"
+        self.addParameter(ParameterRaster(self.INPUT_RASTER, "Input layer", False))
+        self.addParameter(ParameterNumber(self.INTERVAL, "Interval between contour lines", 0.0, 99999999.999999, 10.0))
+        self.addParameter(ParameterString(self.FIELD_NAME, "Attribute name (if not provided, no elecation attribute is attached)", "ELEV", optional=True))
+        self.addParameter(ParameterString(self.EXTRA, "Additional creation parameters", ""))
+
+        self.addOutput(OutputVector(self.OUTPUT_VECTOR, "Output file for contour lines (vector)"))
+
+    def processAlgorithm(self, progress):
+        interval = str(self.getParameterValue(self.INTERVAL))
+        fieldName = str(self.getParameterValue(self.FIELD_NAME))
+        extra = str(self.getParameterValue(self.EXTRA))
+
+        arguments = []
+        if len(fieldName) > 0:
+            arguments.append("-a")
+            arguments.append(fieldName)
+        arguments.append("-i")
+        arguments.append(interval)
+
+        if len(extra) > 0:
+            arguments.append(extra)
+
+        arguments.append(self.getParameterValue(self.INPUT_RASTER))
+        arguments.append(self.getOutputValue(self.OUTPUT_VECTOR))
+
+        GdalUtils.runGdal(["gdal_contour", GdalUtils.escapeAndJoin(arguments)], progress)