[FEATURE] New algorithms to add Z/M values to existing geometries

Allows upgrading geometries to include these dimensions, or
overwriting any existing Z/M values with a new value.

Intended mostly as a test run for QgsProcessingFeatureBasedAlgorithm

python/plugins/processing/algs/help/qgis.yaml

@@ -503,6 +503,10 @@ qgis:selectbyexpression: >
 qgis:selectbylocation: >
   This algorithm creates a selection in a vector layer. The criteria for selecting features is based on the spatial relationship between each feature and the features in an additional layer.
 
+qgis:setmvalue: >
+  This algorithm sets the M value for geometries in a layer.
+
+  If M values already exist in the layer, they will be overwritten with the new value. If no M values exist, the geometry will be upgraded to include M values and the specified value used as the initial M value for all geometries.
 
 qgis:setstyleforrasterlayer: >
   This algorithm sets the style of a raster layer. The style must be defined in a QML file.
@@ -510,6 +514,11 @@ qgis:setstyleforrasterlayer: >
 qgis:setstyleforvectorlayer: >
   This algorithm sets the style of a vector layer. The style must be defined in a QML file.
 
+qgis:setzvalue: >
+  This algorithm sets the Z value for geometries in a layer.
+
+  If Z values already exist in the layer, they will be overwritten with the new value. If no Z values exist, the geometry will be upgraded to include Z values and the specified value used as the initial Z value for all geometries.
+
 qgis:simplifygeometries: >
   This algorithm simplifies the geometries in a line or polygon layer. It creates a new layer with the same features as the ones in the input layer, but with geometries containing a lower number of vertices.
 

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

@@ -89,6 +89,8 @@ from .SelectByAttribute import SelectByAttribute
 from .SelectByExpression import SelectByExpression
 from .ServiceAreaFromLayer import ServiceAreaFromLayer
 from .ServiceAreaFromPoint import ServiceAreaFromPoint
+from .SetMValue import SetMValue
+from .SetZValue import SetZValue
 from .ShortestPathLayerToPoint import ShortestPathLayerToPoint
 from .ShortestPathPointToLayer import ShortestPathPointToLayer
 from .ShortestPathPointToPoint import ShortestPathPointToPoint
@@ -276,6 +278,8 @@ class QGISAlgorithmProvider(QgsProcessingProvider):
                 SelectByExpression(),
                 ServiceAreaFromLayer(),
                 ServiceAreaFromPoint(),
+                SetMValue(),
+                SetZValue(),
                 ShortestPathLayerToPoint(),
                 ShortestPathPointToLayer(),
                 ShortestPathPointToPoint(),

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

@@ -0,0 +1,86 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    SetMValue.py
+    --------------
+    Date                 : July 2017
+    Copyright            : (C) 2017 by Nyall Dawson
+    Email                : nyall dot dawson 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__ = 'Nyall Dawson'
+__date__ = 'July 2017'
+__copyright__ = '(C) 2017, Nyall Dawson'
+
+# This will get replaced with a git SHA1 when you do a git archive323
+
+__revision__ = '$Format:%H$'
+
+import os
+
+from qgis.core import (QgsGeometry,
+                       QgsWkbTypes,
+                       QgsProcessingParameterNumber)
+
+
+from processing.algs.qgis.QgisAlgorithm import QgisFeatureBasedAlgorithm
+
+pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
+
+
+class SetMValue(QgisFeatureBasedAlgorithm):
+
+    M_VALUE = 'M_VALUE'
+
+    def group(self):
+        return self.tr('Vector geometry tools')
+
+    def __init__(self):
+        super().__init__()
+        self.m_value = 0
+
+    def name(self):
+        return 'setmvalue'
+
+    def displayName(self):
+        return self.tr('Set M Value')
+
+    def outputName(self):
+        return self.tr('M Added')
+
+    def tags(self):
+        return self.tr('set,add,m,measure,values').split(',')
+
+    def initParameters(self, config=None):
+        self.addParameter(QgsProcessingParameterNumber(self.M_VALUE,
+                                                       self.tr('M Value'), QgsProcessingParameterNumber.Double, defaultValue=0.0))
+
+    def outputWkbType(self, inputWkb):
+        return QgsWkbTypes.addM(inputWkb)
+
+    def prepareAlgorithm(self, parameters, context, feedback):
+        self.m_value = self.parameterAsDouble(parameters, self.M_VALUE, context)
+        return True
+
+    def processFeature(self, feature, feedback):
+        input_geometry = feature.geometry()
+        if input_geometry:
+            new_geom = input_geometry.geometry().clone()
+            if QgsWkbTypes.hasM(new_geom.wkbType()):
+                # addMValue won't alter existing M values, so drop them first
+                new_geom.dropMValue()
+
+            new_geom.addMValue(self.m_value)
+
+            feature.setGeometry(QgsGeometry(new_geom))
+
+        return True

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

@@ -0,0 +1,86 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    SetZValue.py
+    --------------
+    Date                 : July 2017
+    Copyright            : (C) 2017 by Nyall Dawson
+    Email                : nyall dot dawson 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__ = 'Nyall Dawson'
+__date__ = 'July 2017'
+__copyright__ = '(C) 2017, Nyall Dawson'
+
+# This will get replaced with a git SHA1 when you do a git archive323
+
+__revision__ = '$Format:%H$'
+
+import os
+
+from qgis.core import (QgsGeometry,
+                       QgsWkbTypes,
+                       QgsProcessingParameterNumber)
+
+
+from processing.algs.qgis.QgisAlgorithm import QgisFeatureBasedAlgorithm
+
+pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
+
+
+class SetZValue(QgisFeatureBasedAlgorithm):
+
+    Z_VALUE = 'Z_VALUE'
+
+    def group(self):
+        return self.tr('Vector geometry tools')
+
+    def __init__(self):
+        super().__init__()
+        self.z_value = 0
+
+    def name(self):
+        return 'setzvalue'
+
+    def displayName(self):
+        return self.tr('Set Z Value')
+
+    def outputName(self):
+        return self.tr('Z Added')
+
+    def tags(self):
+        return self.tr('set,add,z,25d,3d,values').split(',')
+
+    def initParameters(self, config=None):
+        self.addParameter(QgsProcessingParameterNumber(self.Z_VALUE,
+                                                       self.tr('Z Value'), QgsProcessingParameterNumber.Double, defaultValue=0.0))
+
+    def outputWkbType(self, inputWkb):
+        return QgsWkbTypes.addZ(inputWkb)
+
+    def prepareAlgorithm(self, parameters, context, feedback):
+        self.z_value = self.parameterAsDouble(parameters, self.Z_VALUE, context)
+        return True
+
+    def processFeature(self, feature, feedback):
+        input_geometry = feature.geometry()
+        if input_geometry:
+            new_geom = input_geometry.geometry().clone()
+            if QgsWkbTypes.hasZ(new_geom.wkbType()):
+                # addZValue won't alter existing Z values, so drop them first
+                new_geom.dropZValue()
+
+            new_geom.addZValue(self.z_value)
+
+            feature.setGeometry(QgsGeometry(new_geom))
+
+        return True

python/plugins/processing/tests/testdata/expected/set_m_value.prj

@@ -0,0 +1 @@
+GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]]

python/plugins/processing/tests/testdata/expected/set_m_value.qpj

@@ -0,0 +1 @@
+GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]]

python/plugins/processing/tests/testdata/expected/set_z_value.prj

@@ -0,0 +1 @@
+GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]]

python/plugins/processing/tests/testdata/expected/set_z_value.qpj

@@ -0,0 +1 @@
+GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]]

python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml

@@ -522,6 +522,30 @@ tests:
         name: expected/multiline_boundary.gml
         type: vector
 
+  - algorithm: qgis:setmvalue
+    name: Set M Value
+    params:
+      INPUT:
+        name: points.gml
+        type: vector
+      M_VALUE: 7
+    results:
+      OUTPUT:
+        name: expected/set_m_value.shp
+        type: vector
+
+  - algorithm: qgis:setzvalue
+    name: Set Z Value
+    params:
+      INPUT:
+        name: points.gml
+        type: vector
+      Z_VALUE: 6
+    results:
+      OUTPUT:
+        name: expected/set_z_value.shp
+        type: vector
+
   - algorithm: qgis:pointonsurface
     name: Point on polygon surface
     params: