[processing] expose Aspect from Raster terrain analysis plugin in toolbox

Author: alexbruy

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

@@ -0,0 +1,64 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    Aspect.py
+    ---------------------
+    Date                 : October 2016
+    Copyright            : (C) 2016 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.                                   *
+*                                                                         *
+***************************************************************************
+"""
+from builtins import str
+
+__author__ = 'Alexander Bruy'
+__date__ = 'October 2016'
+__copyright__ = '(C) 2016, Alexander Bruy'
+
+# This will get replaced with a git SHA1 when you do a git archive
+
+__revision__ = '$Format:%H$'
+
+from qgis.analysis import QgsAspectFilter
+
+from processing.core.GeoAlgorithm import GeoAlgorithm
+from processing.core.parameters import ParameterRaster
+from processing.core.parameters import ParameterNumber
+from processing.core.outputs import OutputRaster
+from processing.tools import raster
+
+
+class Aspect(GeoAlgorithm):
+
+    INPUT_LAYER = 'INPUT_LAYER'
+    Z_FACTOR = 'Z_FACTOR'
+    OUTPUT_LAYER = 'OUTPUT_LAYER'
+
+    def defineCharacteristics(self):
+        self.name, self.i18n_name = self.trAlgorithm('Aspect')
+        self.group, self.i18n_group = self.trAlgorithm('Raster terrain analysis')
+
+        self.addParameter(ParameterRaster(self.INPUT_LAYER,
+                                          self.tr('Elevation layer')))
+        self.addParameter(ParameterNumber(self.Z_FACTOR,
+                                          self.tr('Z factor'), 1.0, 999999.99, 1.0))
+        self.addOutput(OutputRaster(self.OUTPUT_LAYER,
+                                    self.tr('Aspect')))
+
+    def processAlgorithm(self, progress):
+        inputFile = self.getParameterValue(self.INPUT_LAYER)
+        zFactor = self.getParameterValue(self.Z_FACTOR)
+        outputFile = self.getOutputValue(self.OUTPUT_LAYER)
+
+        outputFormat = raster.formatShortNameFromFileName(outputFile)
+
+        aspect = QgsAspectFilter(inputFile, outputFile, outputFormat)
+        aspect.setZFactor(zFactor)
+        aspect.processRaster(None)

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

@@ -158,6 +158,7 @@
 from .Translate import Translate
 from .SingleSidedBuffer import SingleSidedBuffer
 from .PointsAlongGeometry import PointsAlongGeometry
+from .Aspect import Aspect
 
 pluginPath = os.path.normpath(os.path.join(
     os.path.split(os.path.dirname(__file__))[0], os.pardir))
@@ -212,9 +213,9 @@ def __init__(self):
                         RectanglesOvalsDiamondsVariable(),
                         RectanglesOvalsDiamondsFixed(), MergeLines(),
                         BoundingBox(), Boundary(), PointOnSurface(),
-                        OffsetLine(), PolygonCentroids(),
-                        Translate(), SingleSidedBuffer(),
-                        PointsAlongGeometry()
+                        OffsetLine(), PolygonCentroids(), Translate(),
+                        SingleSidedBuffer(), PointsAlongGeometry(),
+                        Aspect(),
                         ]
 
         if hasMatplotlib:

python/plugins/processing/tools/raster.py

@@ -16,9 +16,6 @@
 *                                                                         *
 ***************************************************************************
 """
-from builtins import str
-from builtins import range
-from builtins import object
 
 __author__ = 'Victor Olaya  and Alexander Bruy'
 __date__ = 'February 2013'
@@ -28,16 +25,55 @@
 
 __revision__ = '$Format:%H$'
 
+from builtins import str
+from builtins import range
+from builtins import object
+
+import os
 import struct
+
 import numpy
 from osgeo import gdal
-from osgeo.gdalconst import GA_ReadOnly
+
 from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
 
 
+RASTER_EXTENSION_MAP = None
+
+
+def initGdalData():
+    global RASTER_EXTENSION_MAP
+
+    if RASTER_EXTENSION_MAP is not None:
+        return
+
+    if gdal.GetDriverCount() == 0:
+        gdal.AllRegister()
+
+    RASTER_EXTENSION_MAP = dict()
+    for i in range(gdal.GetDriverCount()):
+        driver = gdal.GetDriver(i)
+        if driver is None:
+            continue
+        md = driver.GetMetadata()
+        if gdal.DCAP_CREATE in md and md[gdal.DCAP_CREATE].lower() == 'yes':
+            ext = md[gdal.DMD_EXTENSION] if gdal.DMD_EXTENSION in md else None
+            if ext is not None and ext != '':
+                RASTER_EXTENSION_MAP[driver.ShortName] = ext
+
+
+def formatShortNameFromFileName(fileName):
+    initGdalData()
+    ext = os.path.splitext(fileName)[1][1:]
+    for k, v in RASTER_EXTENSION_MAP.items():
+        if ext == v:
+            return k
+    return 'GTiff'
+
+
 def scanraster(layer, progress):
     filename = str(layer.source())
-    dataset = gdal.Open(filename, GA_ReadOnly)
+    dataset = gdal.Open(filename, gdal.GA_ReadOnly)
     band = dataset.GetRasterBand(1)
     nodata = band.GetNoDataValue()
     bandtype = gdal.GetDataTypeName(band.DataType)
@@ -114,8 +150,8 @@ def getValue(self, x, y, band=0):
             return self.NODATA
 
     def close(self):
-        format = 'GTiff'
-        driver = gdal.GetDriverByName(format)
+        fmt = 'GTiff'
+        driver = gdal.GetDriverByName(fmt)
         dst_ds = driver.Create(self.fileName, self.nx, self.ny, 1,
                                gdal.GDT_Float32)
         dst_ds.SetProjection(str(self.crs.toWkt()))