Example #1
0
    def processAlgorithm(self, parameters, context, feedback):
        source = self.parameterAsSource(parameters, self.INPUT, context)
        if source is None:
            raise QgsProcessingException(self.invalidSourceError(parameters, self.INPUT))

        if self.parameterAsBool(parameters, self.KEEP_FIELDS, context):
            fields = source.fields()
        else:
            fields = QgsFields()

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
                                               fields, QgsWkbTypes.Polygon, source.sourceCrs())
        if sink is None:
            raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))

        allLinesList = []
        features = source.getFeatures(QgsFeatureRequest().setSubsetOfAttributes([]))
        feedback.pushInfo(QCoreApplication.translate('Polygonize', 'Processing lines…'))
        total = (40.0 / source.featureCount()) if source.featureCount() else 1
        for current, inFeat in enumerate(features):
            if feedback.isCanceled():
                break

            if inFeat.geometry():
                allLinesList.append(inFeat.geometry())
            feedback.setProgress(int(current * total))

        feedback.setProgress(40)

        feedback.pushInfo(QCoreApplication.translate('Polygonize', 'Noding lines…'))
        allLines = QgsGeometry.unaryUnion(allLinesList)
        if feedback.isCanceled():
            return {}

        feedback.setProgress(45)
        feedback.pushInfo(QCoreApplication.translate('Polygonize', 'Polygonizing…'))
        polygons = QgsGeometry.polygonize([allLines])
        if polygons.isEmpty():
            feedback.reportError(self.tr('No polygons were created!'))
        feedback.setProgress(50)

        if not polygons.isEmpty():
            feedback.pushInfo(QCoreApplication.translate('Polygonize', 'Saving polygons…'))
            total = 50.0 / polygons.constGet().numGeometries()
            for i in range(polygons.constGet().numGeometries()):
                if feedback.isCanceled():
                    break

                outFeat = QgsFeature()
                geom = QgsGeometry(polygons.constGet().geometryN(i).clone())
                outFeat.setGeometry(geom)
                sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                feedback.setProgress(50 + int(current * total))

        return {self.OUTPUT: dest_id}
Example #2
0
def buffering(feedback, context, writer, distance, field, useField, layer, dissolve, segments, endCapStyle=1,
              joinStyle=1, mitreLimit=2):

    if useField:
        field = layer.fields().lookupField(field)

    outFeat = QgsFeature()

    current = 0
    features = QgsProcessingUtils.getFeatures(layer, context)
    total = 100.0 / QgsProcessingUtils.featureCount(layer, context)

    # With dissolve
    if dissolve:
        buffered_geometries = []
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance

            inGeom = inFeat.geometry()

            buffered_geometries.append(inGeom.buffer(float(value), segments, endCapStyle, joinStyle, mitreLimit))

            current += 1
            feedback.setProgress(int(current * total))

        final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
        outFeat.setGeometry(final_geometry)
        outFeat.setAttributes(attrs)
        writer.addFeature(outFeat)
    else:
        # Without dissolve
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance
            inGeom = inFeat.geometry()
            outFeat = QgsFeature()
            outGeom = inGeom.buffer(float(value), segments, endCapStyle, joinStyle, mitreLimit)
            outFeat.setGeometry(outGeom)
            outFeat.setAttributes(attrs)
            writer.addFeature(outFeat)
            current += 1
            feedback.setProgress(int(current * total))

    del writer
Example #3
0
    def processAlgorithm(self, parameters, context, feedback):
        vlayer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.INPUT), context)
        output = self.getOutputFromName(self.OUTPUT)
        if self.getParameterValue(self.FIELDS):
            fields = vlayer.fields()
        else:
            fields = QgsFields()
        if self.getParameterValue(self.GEOMETRY):
            fieldsCount = fields.count()
            fields.append(QgsField('area', QVariant.Double, 'double', 16, 2))
            fields.append(QgsField('perimeter', QVariant.Double,
                                   'double', 16, 2))
        allLinesList = []
        features = QgsProcessingUtils.getFeatures(vlayer, context, QgsFeatureRequest().setSubsetOfAttributes([]))
        feedback.pushInfo(self.tr('Processing lines...'))
        total = 40.0 / QgsProcessingUtils.featureCount(vlayer, context)
        for current, inFeat in enumerate(features):
            if inFeat.geometry():
                allLinesList.append(inFeat.geometry())
            feedback.setProgress(int(current * total))

        feedback.setProgress(40)

        feedback.pushInfo(self.tr('Noding lines...'))
        allLines = QgsGeometry.unaryUnion(allLinesList)

        feedback.setProgress(45)
        feedback.pushInfo(self.tr('Polygonizing...'))
        polygons = QgsGeometry.polygonize([allLines])
        if polygons.isEmpty():
            raise GeoAlgorithmExecutionException(self.tr('No polygons were created!'))
        feedback.setProgress(50)

        feedback.pushInfo('Saving polygons...')
        writer = output.getVectorWriter(fields, QgsWkbTypes.Polygon, vlayer.crs(), context)
        total = 50.0 / polygons.geometry().numGeometries()
        for i in range(polygons.geometry().numGeometries()):
            outFeat = QgsFeature()
            geom = QgsGeometry(polygons.geometry().geometryN(i).clone())
            outFeat.setGeometry(geom)
            if self.getParameterValue(self.GEOMETRY):
                outFeat.setAttributes([None] * fieldsCount + [geom.geometry().area(),
                                                              geom.geometry().perimeter()])
            writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
            feedback.setProgress(50 + int(current * total))
        del writer
def _union_geometries(geometries):
    """ Return a geometry which is union of the passed list of geometries.

    :param geometries: Geometries for the union operation.
    :type geometries: list

    :returns: union of geometries
    :rtype: QgsGeometry
    """
    if QGis.QGIS_VERSION_INT >= 20400:
        # woohoo we can use fast union (needs GEOS >= 3.3)
        return QgsGeometry.unaryUnion(geometries)
    else:
        # uhh we need to use slow iterative union
        if len(geometries) == 0:
            return QgsGeometry()
        result_geometry = QgsGeometry(geometries[0])
        for g in geometries[1:]:
            result_geometry = result_geometry.combine(g)
        return result_geometry
Example #5
0
def buffering(progress, writer, distance, field, useField, layer, dissolve,
              segments, endCapStyle=1, joinStyle=1, mitreLimit=2):

    if useField:
        field = layer.fields().lookupField(field)

    outFeat = QgsFeature()

    current = 0
    features = vector.features(layer)
    total = 100.0 / float(len(features))

    # With dissolve
    if dissolve:
        first = True
        buffered_geometries = []
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance

            inGeom = inFeat.geometry()
            if not inGeom:
                ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, 'Feature {} has empty geometry. Skipping...'.format(inFeat.id()))
                continue
            if not inGeom.isGeosValid():
                ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, 'Feature {} has invalid geometry. Skipping...'.format(inFeat.id()))
                continue
            buffered_geometries.append(inGeom.buffer(float(value), segments, endCapStyle, joinStyle, mitreLimit))

            current += 1
            progress.setPercentage(int(current * total))

        final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
        outFeat.setGeometry(final_geometry)
        outFeat.setAttributes(attrs)
        writer.addFeature(outFeat)
    else:
        # Without dissolve
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance
            inGeom = inFeat.geometry()
            outFeat = QgsFeature()
            if inGeom.isEmpty() or inGeom.isGeosEmpty():
                pass
            elif not inGeom.isGeosValid():
                ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, 'Feature {} has invalid geometry. Skipping...'.format(inFeat.id()))
                continue
            else:
                outGeom = inGeom.buffer(float(value), segments, endCapStyle, joinStyle, mitreLimit)
                outFeat.setGeometry(outGeom)
            outFeat.setAttributes(attrs)
            writer.addFeature(outFeat)
            current += 1
            progress.setPercentage(int(current * total))

    del writer
Example #6
0
    def processAlgorithm(self, progress):
        useField = not self.getParameterValue(Dissolve.DISSOLVE_ALL)
        field_names = self.getParameterValue(Dissolve.FIELD)
        vlayerA = dataobjects.getObjectFromUri(
            self.getParameterValue(Dissolve.INPUT))

        writer = self.getOutputFromName(
            Dissolve.OUTPUT).getVectorWriter(
                vlayerA.fields().toList(),
                vlayerA.wkbType(),
                vlayerA.crs())

        outFeat = QgsFeature()
        features = vector.features(vlayerA)
        total = 100.0 / len(features)

        if not useField:
            first = True
            # we dissolve geometries in blocks using unaryUnion
            geom_queue = []
            for current, inFeat in enumerate(features):
                progress.setPercentage(int(current * total))
                if first:
                    outFeat.setAttributes(inFeat.attributes())
                    first = False

                tmpInGeom = inFeat.geometry()
                if tmpInGeom.isEmpty() or tmpInGeom.isGeosEmpty():
                    continue

                errors = tmpInGeom.validateGeometry()
                if len(errors) != 0:
                    for error in errors:
                        ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                               self.tr('ValidateGeometry()'
                                                       'error: One or more '
                                                       'input features have '
                                                       'invalid geometry: ')
                                               + error.what())
                    continue

                geom_queue.append(tmpInGeom)

                if len(geom_queue) > 10000:
                    # queue too long, combine it
                    try:
                        temp_output_geometry = QgsGeometry.unaryUnion(geom_queue)
                        geom_queue = [temp_output_geometry]
                    except:
                        raise GeoAlgorithmExecutionException(
                            self.tr('Geometry exception while dissolving'))

            try:
                outFeat.setGeometry(QgsGeometry.unaryUnion(geom_queue))
            except:
                raise GeoAlgorithmExecutionException(
                    self.tr('Geometry exception while dissolving'))

            writer.addFeature(outFeat)
        else:
            field_indexes = [vlayerA.fields().lookupField(f) for f in field_names.split(';')]

            attribute_dict = {}
            geometry_dict = defaultdict(lambda: [])

            for inFeat in features:
                attrs = inFeat.attributes()

                index_attrs = tuple([attrs[i] for i in field_indexes])

                tmpInGeom = QgsGeometry(inFeat.geometry())
                if tmpInGeom.isGeosEmpty():
                    continue
                errors = tmpInGeom.validateGeometry()
                if len(errors) != 0:
                    for error in errors:
                        ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                               self.tr('ValidateGeometry() '
                                                       'error: One or more input'
                                                       'features have invalid '
                                                       'geometry: ')
                                               + error.what())

                if not index_attrs in attribute_dict:
                    # keep attributes of first feature
                    attribute_dict[index_attrs] = attrs

                geometry_dict[index_attrs].append(tmpInGeom)

            nFeat = len(attribute_dict)

            nElement = 0
            for key, value in list(geometry_dict.items()):
                outFeat = QgsFeature()
                nElement += 1
                progress.setPercentage(int(nElement * 100 / nFeat))
                try:
                    tmpOutGeom = QgsGeometry.unaryUnion(value)
                except:
                    raise GeoAlgorithmExecutionException(
                        self.tr('Geometry exception while dissolving'))
                outFeat.setGeometry(tmpOutGeom)
                outFeat.setAttributes(attribute_dict[key])
                writer.addFeature(outFeat)

        del writer
Example #7
0
def buffering(feedback, context, sink, distance, field, useField, source, dissolve, segments, endCapStyle=1,
              joinStyle=1, miterLimit=2):

    if useField:
        field = source.fields().lookupField(field)

    outFeat = QgsFeature()

    current = 0
    total = 100.0 / source.featureCount() if source.featureCount() else 0

    # With dissolve
    if dissolve:
        attributes_to_fetch = []
        if useField:
            attributes_to_fetch.append(field)

        features = source.getFeatures(QgsFeatureRequest().setSubsetOfAttributes(attributes_to_fetch))
        buffered_geometries = []
        for inFeat in features:
            if feedback.isCanceled():
                break

            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance

            inGeom = inFeat.geometry()

            buffered_geometries.append(inGeom.buffer(float(value), segments, endCapStyle, joinStyle, miterLimit))

            current += 1
            feedback.setProgress(int(current * total))

        final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
        outFeat.setGeometry(final_geometry)
        outFeat.setAttributes(attrs)
        sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
    else:

        features = source.getFeatures()

        # Without dissolve
        for inFeat in features:
            if feedback.isCanceled():
                break
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance
            inGeom = inFeat.geometry()
            outFeat = QgsFeature()
            outGeom = inGeom.buffer(float(value), segments, endCapStyle, joinStyle, miterLimit)
            outFeat.setGeometry(outGeom)
            outFeat.setAttributes(attrs)
            sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
            current += 1
            feedback.setProgress(int(current * total))
Example #8
0
    def processAlgorithm(self, progress):
        useField = not self.getParameterValue(Dissolve.DISSOLVE_ALL)
        fieldname = self.getParameterValue(Dissolve.FIELD)
        vlayerA = dataobjects.getObjectFromUri(
            self.getParameterValue(Dissolve.INPUT))
        vproviderA = vlayerA.dataProvider()
        fields = vlayerA.fields()
        writer = self.getOutputFromName(
            Dissolve.OUTPUT).getVectorWriter(fields,
                                             vproviderA.geometryType(),
                                             vproviderA.crs())
        outFeat = QgsFeature()
        features = vector.features(vlayerA)
        total = 100.0 / len(features)

        if not useField:
            first = True
            for current, inFeat in enumerate(features):
                progress.setPercentage(int(current * total))
                if first:
                    attrs = inFeat.attributes()
                    tmpInGeom = inFeat.geometry()
                    if tmpInGeom.isEmpty() or tmpInGeom.isGeosEmpty():
                        continue
                    errors = tmpInGeom.validateGeometry()
                    if len(errors) != 0:
                        for error in errors:
                            ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                                   self.tr('ValidateGeometry()'
                                                           'error: One or more '
                                                           'input features have '
                                                           'invalid geometry: ')
                                                   + error.what())
                        continue
                    outFeat.setGeometry(tmpInGeom)
                    first = False
                else:
                    tmpInGeom = inFeat.geometry()
                    if tmpInGeom.isEmpty() or tmpInGeom.isGeosEmpty():
                        continue
                    tmpOutGeom = outFeat.geometry()
                    errors = tmpInGeom.validateGeometry()
                    if len(errors) != 0:
                        for error in errors:
                            ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                                   self.tr('ValidateGeometry()'
                                                           'error:One or more input'
                                                           'features have invalid '
                                                           'geometry: ')
                                                   + error.what())
                        continue
                    try:
                        tmpOutGeom = QgsGeometry(tmpOutGeom.combine(tmpInGeom))
                        outFeat.setGeometry(tmpOutGeom)
                    except:
                        raise GeoAlgorithmExecutionException(
                            self.tr('Geometry exception while dissolving'))
            outFeat.setAttributes(attrs)
            writer.addFeature(outFeat)
        else:
            fieldIdx = vlayerA.fieldNameIndex(fieldname)
            unique = vector.getUniqueValues(vlayerA, int(fieldIdx))
            nFeat = len(unique)
            myDict = {}
            attrDict = {}
            for item in unique:
                myDict[unicode(item).strip()] = []
                attrDict[unicode(item).strip()] = None

            unique = None

            for inFeat in features:
                attrs = inFeat.attributes()
                tempItem = attrs[fieldIdx]
                tmpInGeom = QgsGeometry(inFeat.geometry())
                if tmpInGeom.isGeosEmpty():
                    continue
                errors = tmpInGeom.validateGeometry()
                if len(errors) != 0:
                    for error in errors:
                        ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                               self.tr('ValidateGeometry() '
                                                       'error: One or more input'
                                                       'features have invalid '
                                                       'geometry: ')
                                               + error.what())

                if attrDict[unicode(tempItem).strip()] is None:
                    # keep attributes of first feature
                    attrDict[unicode(tempItem).strip()] = attrs

                myDict[unicode(tempItem).strip()].append(tmpInGeom)

            features = None

            nElement = 0
            for key, value in myDict.items():
                nElement += 1
                progress.setPercentage(int(nElement * 100 / nFeat))
                try:
                    tmpOutGeom = QgsGeometry.unaryUnion(value)
                except:
                    raise GeoAlgorithmExecutionException(
                        self.tr('Geometry exception while dissolving'))
                outFeat.setGeometry(tmpOutGeom)
                outFeat.setAttributes(attrDict[key])
                writer.addFeature(outFeat)

        del writer
Example #9
0
def buffering(feedback,
              writer,
              distance,
              field,
              useField,
              layer,
              dissolve,
              segments,
              endCapStyle=1,
              joinStyle=1,
              mitreLimit=2):

    if useField:
        field = layer.fields().lookupField(field)

    outFeat = QgsFeature()

    current = 0
    features = vector.features(layer)
    total = 100.0 / float(len(features))

    # With dissolve
    if dissolve:
        buffered_geometries = []
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance

            inGeom = inFeat.geometry()

            buffered_geometries.append(
                inGeom.buffer(float(value), segments, endCapStyle, joinStyle,
                              mitreLimit))

            current += 1
            feedback.setProgress(int(current * total))

        final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
        outFeat.setGeometry(final_geometry)
        outFeat.setAttributes(attrs)
        writer.addFeature(outFeat)
    else:
        # Without dissolve
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance
            inGeom = inFeat.geometry()
            outFeat = QgsFeature()
            outGeom = inGeom.buffer(float(value), segments, endCapStyle,
                                    joinStyle, mitreLimit)
            outFeat.setGeometry(outGeom)
            outFeat.setAttributes(attrs)
            writer.addFeature(outFeat)
            current += 1
            feedback.setProgress(int(current * total))

    del writer
Example #10
0
File: Clip.py Project: hyperLx/QGIS
    def processAlgorithm(self, context, feedback):
        source_layer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(Clip.INPUT), context)
        mask_layer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(Clip.OVERLAY), context)

        writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(source_layer.fields(),
                                                                     QgsWkbTypes.multiType(source_layer.wkbType()),
                                                                     source_layer.crs(), context)

        # first build up a list of clip geometries
        clip_geoms = []
        for maskFeat in QgsProcessingUtils.getFeatures(mask_layer, context, QgsFeatureRequest().setSubsetOfAttributes([])):
            clip_geoms.append(maskFeat.geometry())

        # are we clipping against a single feature? if so, we can show finer progress reports
        if len(clip_geoms) > 1:
            combined_clip_geom = QgsGeometry.unaryUnion(clip_geoms)
            single_clip_feature = False
        else:
            combined_clip_geom = clip_geoms[0]
            single_clip_feature = True

        # use prepared geometries for faster intersection tests
        engine = QgsGeometry.createGeometryEngine(combined_clip_geom.geometry())
        engine.prepareGeometry()

        tested_feature_ids = set()

        for i, clip_geom in enumerate(clip_geoms):
            input_features = [f for f in QgsProcessingUtils.getFeatures(source_layer, context,
                                                                        QgsFeatureRequest().setFilterRect(clip_geom.boundingBox()))]

            if not input_features:
                continue

            if single_clip_feature:
                total = 100.0 / len(input_features)
            else:
                total = 0

            for current, in_feat in enumerate(input_features):
                if not in_feat.geometry():
                    continue

                if in_feat.id() in tested_feature_ids:
                    # don't retest a feature we have already checked
                    continue

                tested_feature_ids.add(in_feat.id())

                if not engine.intersects(in_feat.geometry().geometry()):
                    continue

                if not engine.contains(in_feat.geometry().geometry()):
                    cur_geom = in_feat.geometry()
                    new_geom = combined_clip_geom.intersection(cur_geom)
                    if new_geom.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(new_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                        int_com = in_feat.geometry().combine(new_geom)
                        int_sym = in_feat.geometry().symDifference(new_geom)
                        new_geom = int_com.difference(int_sym)
                else:
                    # clip geometry totally contains feature geometry, so no need to perform intersection
                    new_geom = in_feat.geometry()

                try:
                    out_feat = QgsFeature()
                    out_feat.setGeometry(new_geom)
                    out_feat.setAttributes(in_feat.attributes())
                    writer.addFeature(out_feat)
                except:
                    QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more '
                                                     'output features ignored due to '
                                                     'invalid geometry.'), self.tr('Processing'), QgsMessageLog.CRITICAL)
                    continue

                if single_clip_feature:
                    feedback.setProgress(int(current * total))

            if not single_clip_feature:
                # coarse progress report for multiple clip geometries
                feedback.setProgress(100.0 * i / len(clip_geoms))

        del writer
Example #11
0
def union(union_a, union_b, callback=None):
    """Union of two vector layers.

    Issue https://github.com/inasafe/inasafe/issues/3186

    Note : This algorithm is copied from :
    https://github.com/qgis/QGIS/blob/master/python/plugins/processing/algs/
    qgis/Union.py

    :param union_a: The vector layer for the union.
    :type union_a: QgsVectorLayer

    :param union_b: The vector layer for the union.
    :type union_b: QgsVectorLayer

    :param callback: A function to all to indicate progress. The function
        should accept params 'current' (int), 'maximum' (int) and 'step' (str).
        Defaults to None.
    :type callback: function

    :return: The clip vector layer.
    :rtype: QgsVectorLayer

    .. versionadded:: 4.0
    """
    output_layer_name = union_steps['output_layer_name']
    processing_step = union_steps['step_name']
    output_layer_name = output_layer_name % (
        union_a.keywords['layer_purpose'],
        union_b.keywords['layer_purpose']
    )

    fields = union_a.fields()
    fields.extend(union_b.fields())

    writer = create_memory_layer(
        output_layer_name,
        union_a.geometryType(),
        union_a.crs(),
        fields
    )
    keywords_union_1 = union_a.keywords
    keywords_union_2 = union_b.keywords
    inasafe_fields_union_1 = keywords_union_1['inasafe_fields']
    inasafe_fields_union_2 = keywords_union_2['inasafe_fields']
    inasafe_fields = inasafe_fields_union_1
    inasafe_fields.update(inasafe_fields_union_2)

    # use to avoid modifying original source
    writer.keywords = dict(union_a.keywords)
    writer.keywords['inasafe_fields'] = inasafe_fields
    writer.keywords['title'] = output_layer_name
    writer.keywords['layer_purpose'] = 'aggregate_hazard'
    writer.keywords['hazard_keywords'] = keywords_union_1.copy()
    writer.keywords['aggregation_keywords'] = keywords_union_2.copy()
    skip_field = inasafe_fields_union_2[aggregation_id_field['key']]
    not_null_field_index = writer.fieldNameIndex(skip_field)

    writer.startEditing()

    # Begin copy/paste from Processing plugin.
    # Please follow their code as their code is optimized.
    # The code below is not following our coding standards because we want to
    # be able to track any diffs from QGIS easily.

    index_a = create_spatial_index(union_b)
    index_b = create_spatial_index(union_a)

    count = 0
    n_element = 0
    # Todo fix callback
    # nFeat = len(union_a.getFeatures())
    for in_feat_a in union_a.getFeatures():
        # progress.setPercentage(nElement / float(nFeat) * 50)
        n_element += 1
        list_intersecting_b = []
        geom = geometry_checker(in_feat_a.geometry())
        at_map_a = in_feat_a.attributes()
        intersects = index_a.intersects(geom.boundingBox())
        if len(intersects) < 1:
            try:
                _write_feature(at_map_a, geom, writer, not_null_field_index)
            except:
                # This really shouldn't happen, as we haven't
                # edited the input geom at all
                LOGGER.debug(
                    tr('Feature geometry error: One or more output features '
                       'ignored due to invalid geometry.'))
        else:
            request = QgsFeatureRequest().setFilterFids(intersects)

            engine = QgsGeometry.createGeometryEngine(geom.geometry())
            engine.prepareGeometry()

            for in_feat_b in union_b.getFeatures(request):
                count += 1

                at_map_b = in_feat_b.attributes()
                tmp_geom = geometry_checker(in_feat_b.geometry())

                if engine.intersects(tmp_geom.geometry()):
                    int_geom = geometry_checker(geom.intersection(tmp_geom))
                    list_intersecting_b.append(QgsGeometry(tmp_geom))

                    if not int_geom:
                        # There was a problem creating the intersection
                        # LOGGER.debug(
                        #     tr('GEOS geoprocessing error: One or more input '
                        #        'features have invalid geometry.'))
                        pass
                        int_geom = QgsGeometry()
                    else:
                        int_geom = QgsGeometry(int_geom)

                    if int_geom.wkbType() == QgsWKBTypes.Unknown\
                            or QgsWKBTypes.flatType(
                            int_geom.geometry().wkbType()) == \
                                    QgsWKBTypes.GeometryCollection:
                        # Intersection produced different geometry types
                        temp_list = int_geom.asGeometryCollection()
                        for i in temp_list:
                            if i.type() == geom.type():
                                int_geom = QgsGeometry(geometry_checker(i))
                                try:
                                    _write_feature(
                                        at_map_a + at_map_b,
                                        int_geom,
                                        writer,
                                        not_null_field_index,
                                    )
                                except:
                                    LOGGER.debug(
                                        tr('Feature geometry error: One or '
                                           'more output features ignored due '
                                           'to invalid geometry.'))
                    else:
                        # Geometry list: prevents writing error
                        # in geometries of different types
                        # produced by the intersection
                        # fix #3549
                        if int_geom.wkbType() in wkb_type_groups[
                            wkb_type_groups[int_geom.wkbType()]]:
                            try:
                                _write_feature(
                                    at_map_a + at_map_b,
                                    int_geom,
                                    writer,
                                    not_null_field_index)
                            except:
                                LOGGER.debug(
                                    tr('Feature geometry error: One or more '
                                       'output features ignored due to '
                                       'invalid geometry.'))

            # the remaining bit of inFeatA's geometry
            # if there is nothing left, this will just silently fail and we
            # are good
            diff_geom = QgsGeometry(geom)
            if len(list_intersecting_b) != 0:
                int_b = QgsGeometry.unaryUnion(list_intersecting_b)
                diff_geom = geometry_checker(diff_geom.difference(int_b))
                if diff_geom is None or \
                    diff_geom.isGeosEmpty() or not diff_geom.isGeosValid():
                    # LOGGER.debug(
                    #     tr('GEOS geoprocessing error: One or more input '
                    #        'features have invalid geometry.'))
                    pass

            if diff_geom is not None and (
                            diff_geom.wkbType() == 0 or QgsWKBTypes.flatType(
                    diff_geom.geometry().wkbType()) ==
                    QgsWKBTypes.GeometryCollection):
                temp_list = diff_geom.asGeometryCollection()
                for i in temp_list:
                    if i.type() == geom.type():
                        diff_geom = QgsGeometry(geometry_checker(i))
            try:
                _write_feature(
                    at_map_a,
                    diff_geom,
                    writer,
                    not_null_field_index)
            except:
                LOGGER.debug(
                    tr('Feature geometry error: One or more output features '
                       'ignored due to invalid geometry.'))

    length = len(union_a.fields())
    at_map_a = [None] * length

    # nFeat = len(union_b.getFeatures())
    for in_feat_a in union_b.getFeatures():
        # progress.setPercentage(nElement / float(nFeat) * 100)
        add = False
        geom = geometry_checker(in_feat_a.geometry())
        atMap = [None] * length
        atMap.extend(in_feat_a.attributes())
        intersects = index_b.intersects(geom.boundingBox())
        lstIntersectingA = []

        for id in intersects:
            request = QgsFeatureRequest().setFilterFid(id)
            inFeatB = union_a.getFeatures(request).next()
            atMapB = inFeatB.attributes()
            tmpGeom = QgsGeometry(geometry_checker(inFeatB.geometry()))

            if geom.intersects(tmpGeom):
                lstIntersectingA.append(tmpGeom)

        if len(lstIntersectingA) == 0:
            res_geom = geom
        else:
            intA = QgsGeometry.unaryUnion(lstIntersectingA)
            res_geom = geom.difference(intA)
            if res_geom is None:
                # LOGGER.debug(
                #    tr('GEOS geoprocessing error: One or more input features '
                #        'have null geometry.'))
                pass
                continue  # maybe it is better to fail like @gustry
                # does below ....
            if res_geom.isGeosEmpty() or not res_geom.isGeosValid():
                # LOGGER.debug(
                #    tr('GEOS geoprocessing error: One or more input features '
                #        'have invalid geometry.'))
                pass

        try:
            _write_feature(atMap, res_geom, writer, not_null_field_index)
        except:
            # LOGGER.debug(
            #     tr('Feature geometry error: One or more output features '
            #        'ignored due to invalid geometry.'))
            pass

        n_element += 1

    # End of copy/paste from processing

    writer.commitChanges()

    fill_hazard_class(writer)

    check_layer(writer)
    return writer
Example #12
0
    def processAlgorithm(self, parameters, context, feedback):
        expr_context = self.createExpressionContext(parameters, context, self.source)
        self.group_by_expr.prepare(expr_context)

        # Group features in memory layers
        source = self.source
        count = self.source.featureCount()
        if count:
            progress_step = 50.0 / count
        current = 0
        groups = {}
        keys = []  # We need deterministic order for the tests
        feature = QgsFeature()
        for feature in self.source.getFeatures():
            expr_context.setFeature(feature)
            group_by_value = self.evaluateExpression(self.group_by_expr, expr_context)

            # Get an hashable key for the dict
            key = group_by_value
            if isinstance(key, list):
                key = tuple(key)

            group = groups.get(key, None)
            if group is None:
                sink, id = QgsProcessingUtils.createFeatureSink(
                    'memory:',
                    context,
                    source.fields(),
                    source.wkbType(),
                    source.sourceCrs())
                layer = QgsProcessingUtils.mapLayerFromString(id, context)
                group = {
                    'sink': sink,
                    'layer': layer,
                    'feature': feature
                }
                groups[key] = group
                keys.append(key)

            group['sink'].addFeature(feature, QgsFeatureSink.FastInsert)

            current += 1
            feedback.setProgress(int(current * progress_step))
            if feedback.isCanceled():
                return

        (sink, dest_id) = self.parameterAsSink(parameters,
                                               self.OUTPUT,
                                               context,
                                               self.fields,
                                               QgsWkbTypes.multiType(source.wkbType()),
                                               source.sourceCrs())
        if sink is None:
            raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))

        # Calculate aggregates on memory layers
        if len(keys):
            progress_step = 50.0 / len(keys)
        for current, key in enumerate(keys):
            group = groups[key]
            expr_context = self.createExpressionContext(parameters, context)
            expr_context.appendScope(QgsExpressionContextUtils.layerScope(group['layer']))
            expr_context.setFeature(group['feature'])

            geometry = self.evaluateExpression(self.geometry_expr, expr_context)
            if geometry is not None and not geometry.isEmpty():
                geometry = QgsGeometry.unaryUnion(geometry.asGeometryCollection())
                if geometry.isEmpty():
                    raise QgsProcessingException(
                        'Impossible to combine geometries for {} = {}'
                        .format(self.group_by, group_by_value))

            attrs = []
            for fields_expr in self.fields_expr:
                attrs.append(self.evaluateExpression(fields_expr, expr_context))

            # Write output feature
            outFeat = QgsFeature()
            if geometry is not None:
                outFeat.setGeometry(geometry)
            outFeat.setAttributes(attrs)
            sink.addFeature(outFeat, QgsFeatureSink.FastInsert)

            feedback.setProgress(50 + int(current * progress_step))
            if feedback.isCanceled():
                return

        return {self.OUTPUT: dest_id}
Example #13
0
def buffering(feedback,
              context,
              sink,
              distance,
              field,
              useField,
              source,
              dissolve,
              segments,
              endCapStyle=1,
              joinStyle=1,
              miterLimit=2):

    if useField:
        field = source.fields().lookupField(field)

    outFeat = QgsFeature()

    current = 0
    total = 100.0 / source.featureCount() if source.featureCount() else 0

    # With dissolve
    if dissolve:
        attributes_to_fetch = []
        if useField:
            attributes_to_fetch.append(field)

        features = source.getFeatures(
            QgsFeatureRequest().setSubsetOfAttributes(attributes_to_fetch))
        buffered_geometries = []
        for inFeat in features:
            if feedback.isCanceled():
                break

            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance

            inGeom = inFeat.geometry()

            buffered_geometries.append(
                inGeom.buffer(float(value), segments, endCapStyle, joinStyle,
                              miterLimit))

            current += 1
            feedback.setProgress(int(current * total))

        final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
        outFeat.setGeometry(final_geometry)
        outFeat.setAttributes(attrs)
        sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
    else:

        features = source.getFeatures()

        # Without dissolve
        for inFeat in features:
            if feedback.isCanceled():
                break
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance
            inGeom = inFeat.geometry()
            outFeat = QgsFeature()
            outGeom = inGeom.buffer(float(value), segments, endCapStyle,
                                    joinStyle, miterLimit)
            outFeat.setGeometry(outGeom)
            outFeat.setAttributes(attrs)
            sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
            current += 1
            feedback.setProgress(int(current * total))
Example #14
0
    def linearMatrix(self, parameters, context, source, inField, target_source,
                     targetField, same_source_and_target, matType, nPoints,
                     feedback):

        if same_source_and_target:
            # need to fetch an extra point from the index, since the closest match will always be the same
            # as the input feature
            nPoints += 1

        inIdx = source.fields().lookupField(inField)
        outIdx = target_source.fields().lookupField(targetField)

        fields = QgsFields()
        input_id_field = source.fields()[inIdx]
        input_id_field.setName('InputID')
        fields.append(input_id_field)
        if matType == 0:
            target_id_field = target_source.fields()[outIdx]
            target_id_field.setName('TargetID')
            fields.append(target_id_field)
            fields.append(QgsField('Distance', QVariant.Double))
        else:
            fields.append(QgsField('MEAN', QVariant.Double))
            fields.append(QgsField('STDDEV', QVariant.Double))
            fields.append(QgsField('MIN', QVariant.Double))
            fields.append(QgsField('MAX', QVariant.Double))

        out_wkb = QgsWkbTypes.multiType(
            source.wkbType()) if matType == 0 else source.wkbType()
        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT,
                                               context, fields, out_wkb,
                                               source.sourceCrs())
        if sink is None:
            raise QgsProcessingException(
                self.invalidSinkError(parameters, self.OUTPUT))

        index = QgsSpatialIndex(
            target_source.getFeatures(
                QgsFeatureRequest().setSubsetOfAttributes(
                    []).setDestinationCrs(source.sourceCrs(),
                                          context.transformContext())),
            feedback)

        distArea = QgsDistanceArea()
        distArea.setSourceCrs(source.sourceCrs(), context.transformContext())
        distArea.setEllipsoid(context.project().ellipsoid())

        features = source.getFeatures(
            QgsFeatureRequest().setSubsetOfAttributes([inIdx]))
        total = 100.0 / source.featureCount() if source.featureCount() else 0
        for current, inFeat in enumerate(features):
            if feedback.isCanceled():
                break

            inGeom = inFeat.geometry()
            inID = str(inFeat[inIdx])
            featList = index.nearestNeighbor(inGeom.asPoint(), nPoints)
            distList = []
            vari = 0.0
            request = QgsFeatureRequest().setFilterFids(
                featList).setSubsetOfAttributes([outIdx]).setDestinationCrs(
                    source.sourceCrs(), context.transformContext())
            for outFeat in target_source.getFeatures(request):
                if feedback.isCanceled():
                    break

                if same_source_and_target and inFeat.id() == outFeat.id():
                    continue

                outID = outFeat[outIdx]
                outGeom = outFeat.geometry()
                dist = distArea.measureLine(inGeom.asPoint(),
                                            outGeom.asPoint())

                if matType == 0:
                    out_feature = QgsFeature()
                    out_geom = QgsGeometry.unaryUnion(
                        [inFeat.geometry(),
                         outFeat.geometry()])
                    out_feature.setGeometry(out_geom)
                    out_feature.setAttributes([inID, outID, dist])
                    sink.addFeature(out_feature, QgsFeatureSink.FastInsert)
                else:
                    distList.append(float(dist))

            if matType != 0:
                mean = sum(distList) / len(distList)
                for i in distList:
                    vari += (i - mean) * (i - mean)
                vari = math.sqrt(vari / len(distList))

                out_feature = QgsFeature()
                out_feature.setGeometry(inFeat.geometry())
                out_feature.setAttributes(
                    [inID, mean, vari,
                     min(distList),
                     max(distList)])
                sink.addFeature(out_feature, QgsFeatureSink.FastInsert)

            feedback.setProgress(int(current * total))

        return {self.OUTPUT: dest_id}
Example #15
0
    def processAlgorithm(self, progress):
        useField = not self.getParameterValue(Dissolve.DISSOLVE_ALL)
        field_names = self.getParameterValue(Dissolve.FIELD)
        vlayerA = dataobjects.getObjectFromUri(
            self.getParameterValue(Dissolve.INPUT))

        writer = self.getOutputFromName(Dissolve.OUTPUT).getVectorWriter(
            vlayerA.fields().toList(), vlayerA.wkbType(), vlayerA.crs())

        outFeat = QgsFeature()
        features = vector.features(vlayerA)
        total = 100.0 / len(features)

        if not useField:
            first = True
            # we dissolve geometries in blocks using unaryUnion
            geom_queue = []
            for current, inFeat in enumerate(features):
                progress.setPercentage(int(current * total))
                if first:
                    outFeat.setAttributes(inFeat.attributes())
                    first = False

                tmpInGeom = inFeat.geometry()
                if tmpInGeom.isEmpty() or tmpInGeom.isGeosEmpty():
                    continue

                errors = tmpInGeom.validateGeometry()
                if len(errors) != 0:
                    for error in errors:
                        ProcessingLog.addToLog(
                            ProcessingLog.LOG_ERROR,
                            self.tr('ValidateGeometry()'
                                    'error: One or more '
                                    'input features have '
                                    'invalid geometry: ') + error.what())
                    continue

                geom_queue.append(tmpInGeom)

                if len(geom_queue) > 10000:
                    # queue too long, combine it
                    try:
                        temp_output_geometry = QgsGeometry.unaryUnion(
                            geom_queue)
                        geom_queue = [temp_output_geometry]
                    except:
                        raise GeoAlgorithmExecutionException(
                            self.tr('Geometry exception while dissolving'))

            try:
                outFeat.setGeometry(QgsGeometry.unaryUnion(geom_queue))
            except:
                raise GeoAlgorithmExecutionException(
                    self.tr('Geometry exception while dissolving'))

            writer.addFeature(outFeat)
        else:
            field_indexes = [
                vlayerA.fields().lookupField(f) for f in field_names.split(';')
            ]

            attribute_dict = {}
            geometry_dict = defaultdict(lambda: [])

            for inFeat in features:
                attrs = inFeat.attributes()

                index_attrs = tuple([attrs[i] for i in field_indexes])

                tmpInGeom = QgsGeometry(inFeat.geometry())
                if tmpInGeom.isGeosEmpty():
                    continue
                errors = tmpInGeom.validateGeometry()
                if len(errors) != 0:
                    for error in errors:
                        ProcessingLog.addToLog(
                            ProcessingLog.LOG_ERROR,
                            self.tr('ValidateGeometry() '
                                    'error: One or more input'
                                    'features have invalid '
                                    'geometry: ') + error.what())

                if not index_attrs in attribute_dict:
                    # keep attributes of first feature
                    attribute_dict[index_attrs] = attrs

                geometry_dict[index_attrs].append(tmpInGeom)

            nFeat = len(attribute_dict)

            nElement = 0
            for key, value in list(geometry_dict.items()):
                outFeat = QgsFeature()
                nElement += 1
                progress.setPercentage(int(nElement * 100 / nFeat))
                try:
                    tmpOutGeom = QgsGeometry.unaryUnion(value)
                except:
                    raise GeoAlgorithmExecutionException(
                        self.tr('Geometry exception while dissolving'))
                outFeat.setGeometry(tmpOutGeom)
                outFeat.setAttributes(attribute_dict[key])
                writer.addFeature(outFeat)

        del writer
Example #16
0
    def processAlgorithm(self, progress):
        vlayerA = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT))
        vlayerB = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT2))

        geomType = vlayerA.wkbType()
        fields = vector.combineVectorFields(vlayerA, vlayerB)
        writer = self.getOutputFromName(Union.OUTPUT).getVectorWriter(fields,
                                                                      geomType, vlayerA.crs())
        inFeatA = QgsFeature()
        inFeatB = QgsFeature()
        outFeat = QgsFeature()
        indexA = vector.spatialindex(vlayerB)
        indexB = vector.spatialindex(vlayerA)

        count = 0
        nElement = 0
        featuresA = vector.features(vlayerA)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 50)
            nElement += 1
            lstIntersectingB = []
            geom = inFeatA.geometry()
            atMapA = inFeatA.attributes()
            intersects = indexA.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            else:
                request = QgsFeatureRequest().setFilterFids(intersects)

                engine = QgsGeometry.createGeometryEngine(geom.geometry())
                engine.prepareGeometry()

                for inFeatB in vlayerB.getFeatures(request):
                    count += 1

                    atMapB = inFeatB.attributes()
                    tmpGeom = inFeatB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if not int_geom:
                            # There was a problem creating the intersection
                            ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                   self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))
                            int_geom = QgsGeometry()
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if int_geom.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(int_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                                    try:
                                        outFeat.setGeometry(int_geom)
                                        outFeat.setAttributes(atMapA + atMapB)
                                        writer.addFeature(outFeat)
                                    except:
                                        ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                               self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
                        else:
                            # Geometry list: prevents writing error
                            # in geometries of different types
                            # produced by the intersection
                            # fix #3549
                            if int_geom.wkbType() in wkbTypeGroups[wkbTypeGroups[int_geom.wkbType()]]:
                                try:
                                    outFeat.setGeometry(int_geom)
                                    outFeat.setAttributes(atMapA + atMapB)
                                    writer.addFeature(outFeat)
                                except:
                                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

                # the remaining bit of inFeatA's geometry
                # if there is nothing left, this will just silently fail and we're good
                diff_geom = QgsGeometry(geom)
                if len(lstIntersectingB) != 0:
                    intB = QgsGeometry.unaryUnion(lstIntersectingB)
                    diff_geom = diff_geom.difference(intB)
                    if diff_geom.isGeosEmpty() or not diff_geom.isGeosValid():
                        ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                               self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))

                if diff_geom.wkbType() == 0 or QgsWkbTypes.flatType(diff_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                    temp_list = diff_geom.asGeometryCollection()
                    for i in temp_list:
                        if i.type() == geom.type():
                            diff_geom = QgsGeometry(i)
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

        length = len(vlayerA.fields())
        atMapA = [None] * length

        featuresA = vector.features(vlayerB)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 100)
            add = False
            geom = inFeatA.geometry()
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(inFeatA.attributes())
            intersects = indexB.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            else:
                request = QgsFeatureRequest().setFilterFids(intersects)

                # use prepared geometries for faster intersection tests
                engine = QgsGeometry.createGeometryEngine(diff_geom.geometry())
                engine.prepareGeometry()

                for inFeatB in vlayerA.getFeatures(request):
                    atMapB = inFeatB.attributes()
                    tmpGeom = inFeatB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        add = True
                        diff_geom = QgsGeometry(diff_geom.difference(tmpGeom))
                        if diff_geom.isGeosEmpty() or not diff_geom.isGeosValid():
                            ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                                   self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))
                    else:
                        try:
                            # Ihis only happends if the bounding box
                            # intersects, but the geometry doesn't
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            writer.addFeature(outFeat)
                        except:
                            ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                   self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

            if add:
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            nElement += 1

        del writer
Example #17
0
    def get_access_isochrones(self):
        """
        Making the accessibility isochrones in few steps:
        - make a grid of points aroung the origin point,
        - snap each point (using OSRM locate function) on the road network,
        - get the time-distance between the origin point and each of these pts
            (using OSRM table function),
        - make an interpolation grid to extract polygons corresponding to the
            desired time intervals (using matplotlib library),
        - render the polygon.
        """
        try:
            self.host = check_host(self.lineEdit_host.text())
            self.profile = check_profile_name(self.lineEdit_profileName.text())
        except (ValueError, AssertionError) as err:
            self.iface.messageBar().pushMessage(
                "Error", "Please provide a valid non-empty URL", duration=10)
            return

        if 'clicking' in self.comboBox_method.currentText():
            pts = self.get_points_from_canvas()
        elif 'selecting' in self.comboBox_method.currentText():
            layer = self.comboBox_pointlayer.currentLayer()
            pts, _ = get_coords_ids(
                layer, '', on_selected=self.checkBox_selectedFt.isChecked())
            pts = tuple(pts)

        if not pts:
            return

        max_time = self.spinBox_max.value()
        interval_time = self.spinBox_intervall.value()
        nb_inter = int(round(max_time / interval_time)) + 1
        levels = tuple([nb for nb in xrange(0, int(
            max_time + 1) + interval_time, interval_time)][:nb_inter])

        self.make_prog_bar()
        self.max_points = 750 if len(pts) == 1 else 250
        self.polygons = []

        pts = [{"point": pt, "max": max_time, "levels": levels,
                "host": self.host, "profile": self.profile, "max_points": self.max_points}
                for pt in pts]

        pool = ThreadPool(processes=4 if len(pts) >= 4 else len(pts))

        try:
            self.polygons = [i for i in pool.map(prep_access, pts)]
        except Exception as err:
            self.display_error(err, 1)
            return

        if len(self.polygons) == 1:
            self.polygons = self.polygons[0]
        else:
            self.polygons = np.array(self.polygons).transpose().tolist()
            self.polygons = [QgsGeometry.unaryUnion(polys) for polys in self.polygons]

        isochrone_layer = QgsVectorLayer(
            "MultiPolygon?crs=epsg:4326&field=id:integer"
            "&field=min:integer(10)"
            "&field=max:integer(10)",
            "isochrone_osrm_{}".format(self.nb_isocr), "memory")
        data_provider = isochrone_layer.dataProvider()
        # Add the features to the layer to display :
        features = []
        levels = levels[1:]
        self.progress.setValue(8.5)
        for i, poly in enumerate(self.polygons):
            if not poly: continue
            ft = QgsFeature()
            ft.setGeometry(poly)
            ft.setAttributes(
                [i, levels[i] - interval_time, levels[i]])
            features.append(ft)
        data_provider.addFeatures(features[::-1])
        self.nb_isocr += 1
        self.progress.setValue(9.5)

        # Render the value :
        renderer = self.prepare_renderer(
            levels, interval_time, len(self.polygons))
        isochrone_layer.setRendererV2(renderer)
        isochrone_layer.setLayerTransparency(25)
        self.iface.messageBar().clearWidgets()
        QgsMapLayerRegistry.instance().addMapLayer(isochrone_layer)

        self.add_final_pts(pts)
        self.iface.setActiveLayer(isochrone_layer)
Example #18
0
    def processAlgorithm(self, parameters, context, feedback):
        sourceA = self.parameterAsSource(parameters, self.INPUT, context)
        sourceB = self.parameterAsSource(parameters, self.OVERLAY, context)

        geomType = QgsWkbTypes.multiType(sourceA.wkbType())
        fields = QgsProcessingUtils.combineFields(sourceA.fields(),
                                                  sourceB.fields())

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT,
                                               context, fields, geomType,
                                               sourceA.sourceCrs())

        featA = QgsFeature()
        featB = QgsFeature()
        outFeat = QgsFeature()

        indexA = QgsSpatialIndex(sourceA, feedback)
        indexB = QgsSpatialIndex(
            sourceB.getFeatures(QgsFeatureRequest().setSubsetOfAttributes(
                []).setDestinationCrs(sourceA.sourceCrs(),
                                      context.transformContext())), feedback)

        total = 100.0 / (sourceA.featureCount() *
                         sourceB.featureCount()) if sourceA.featureCount(
                         ) and sourceB.featureCount() else 1
        count = 0

        for featA in sourceA.getFeatures():
            if feedback.isCanceled():
                break

            lstIntersectingB = []
            geom = featA.geometry()
            atMapA = featA.attributes()
            intersects = indexB.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    geom.convertToMultiType()
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    feedback.pushInfo(
                        self.
                        tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                           ))
            else:
                request = QgsFeatureRequest().setFilterFids(
                    intersects).setSubsetOfAttributes([])
                request.setDestinationCrs(sourceA.sourceCrs(),
                                          context.transformContext())

                engine = QgsGeometry.createGeometryEngine(geom.constGet())
                engine.prepareGeometry()

                for featB in sourceB.getFeatures(request):
                    atMapB = featB.attributes()
                    tmpGeom = featB.geometry()

                    if engine.intersects(tmpGeom.constGet()):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if not int_geom:
                            # There was a problem creating the intersection
                            feedback.pushInfo(
                                self.
                                tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                                   ))
                            int_geom = QgsGeometry()
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if int_geom.wkbType(
                        ) == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(
                                int_geom.wkbType(
                                )) == QgsWkbTypes.GeometryCollection:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                                    try:
                                        int_geom.convertToMultiType()
                                        outFeat.setGeometry(int_geom)
                                        outFeat.setAttributes(atMapA + atMapB)
                                        sink.addFeature(
                                            outFeat, QgsFeatureSink.FastInsert)
                                    except:
                                        feedback.pushInfo(
                                            self.
                                            tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                                               ))
                        else:
                            # Geometry list: prevents writing error
                            # in geometries of different types
                            # produced by the intersection
                            # fix #3549
                            if QgsWkbTypes.geometryType(int_geom.wkbType(
                            )) == QgsWkbTypes.geometryType(geomType):
                                try:
                                    int_geom.convertToMultiType()
                                    outFeat.setGeometry(int_geom)
                                    outFeat.setAttributes(atMapA + atMapB)
                                    sink.addFeature(outFeat,
                                                    QgsFeatureSink.FastInsert)
                                except:
                                    feedback.pushInfo(
                                        self.
                                        tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                                           ))

                # the remaining bit of featA's geometry
                # if there is nothing left, this will just silently fail and we're good
                diff_geom = QgsGeometry(geom)
                if len(lstIntersectingB) != 0:
                    intB = QgsGeometry.unaryUnion(lstIntersectingB)
                    diff_geom = diff_geom.difference(intB)

                if diff_geom.wkbType(
                ) == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(
                        diff_geom.wkbType()) == QgsWkbTypes.GeometryCollection:
                    temp_list = diff_geom.asGeometryCollection()
                    for i in temp_list:
                        if i.type() == geom.type():
                            diff_geom = QgsGeometry(i)
                try:
                    diff_geom.convertToMultiType()
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    feedback.pushInfo(
                        self.
                        tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                           ))

            count += 1
            feedback.setProgress(int(count * total))

        length = len(sourceA.fields())
        atMapA = [None] * length

        for featA in sourceB.getFeatures(QgsFeatureRequest().setDestinationCrs(
                sourceA.sourceCrs(), context.transformContext())):
            if feedback.isCanceled():
                break

            add = False
            geom = featA.geometry()
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(featA.attributes())
            intersects = indexA.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    geom.convertToMultiType()
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    feedback.pushInfo(
                        self.
                        tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                           ))
            else:
                request = QgsFeatureRequest().setFilterFids(
                    intersects).setSubsetOfAttributes([])
                request.setDestinationCrs(sourceA.sourceCrs(),
                                          context.transformContext())

                # use prepared geometries for faster intersection tests
                engine = QgsGeometry.createGeometryEngine(diff_geom.constGet())
                engine.prepareGeometry()

                for featB in sourceA.getFeatures(request):
                    atMapB = featB.attributes()
                    tmpGeom = featB.geometry()

                    if engine.intersects(tmpGeom.constGet()):
                        add = True
                        diff_geom = QgsGeometry(diff_geom.difference(tmpGeom))
                    else:
                        try:
                            # Ihis only happens if the bounding box
                            # intersects, but the geometry doesn't
                            diff_geom.convertToMultiType()
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                        except:
                            feedback.pushInfo(
                                self.
                                tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                                   ))

            if add:
                try:
                    diff_geom.convertToMultiType()
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    feedback.pushInfo(
                        self.
                        tr('Feature geometry error: One or more output features ignored due to invalid geometry.'
                           ))

            count += 1
            feedback.setProgress(int(count * total))

        return {self.OUTPUT: dest_id}
Example #19
0
File: Union.py Project: wsyscu/QGIS
    def processAlgorithm(self, progress):
        vlayerA = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT))
        vlayerB = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT2))
        GEOS_EXCEPT = True
        FEATURE_EXCEPT = True
        vproviderA = vlayerA.dataProvider()

        fields = vector.combineVectorFields(vlayerA, vlayerB)
        names = [field.name() for field in fields]
        ProcessingLog.addToLog(ProcessingLog.LOG_INFO, unicode(names))
        writer = self.getOutputFromName(Union.OUTPUT).getVectorWriter(fields,
                                                                      vproviderA.geometryType(), vproviderA.crs())
        inFeatA = QgsFeature()
        inFeatB = QgsFeature()
        outFeat = QgsFeature()
        indexA = vector.spatialindex(vlayerB)
        indexB = vector.spatialindex(vlayerA)

        count = 0
        nElement = 0
        featuresA = vector.features(vlayerA)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 50)
            nElement += 1
            lstIntersectingB = []
            geom = QgsGeometry(inFeatA.geometry())
            atMapA = inFeatA.attributes()
            intersects = indexA.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    raise GeoAlgorithmExecutionException(
                        self.tr('Feature exception while computing union'))
            else:
                for id in intersects:
                    count += 1
                    request = QgsFeatureRequest().setFilterFid(id)
                    inFeatB = vlayerB.getFeatures(request).next()
                    atMapB = inFeatB.attributes()
                    tmpGeom = QgsGeometry(inFeatB.geometry())

                    if geom.intersects(tmpGeom):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if int_geom is None:
                           # There was a problem creating the intersection
                            raise GeoAlgorithmExecutionException(
                                self.tr('Geometry exception while computing '
                                        'intersection'))
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if int_geom.wkbType() == 0:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                        try:
                            outFeat.setGeometry(int_geom)
                            attrs = []
                            attrs.extend(atMapA)
                            attrs.extend(atMapB)
                            outFeat.setAttributes(attrs)
                            writer.addFeature(outFeat)
                        except Exception as err:
                            raise GeoAlgorithmExecutionException(
                                self.tr('Feature exception while computing union'))

                try:
                        # the remaining bit of inFeatA's geometry
                        # if there is nothing left, this will just silently fail and we're good
                        diff_geom = QgsGeometry(geom)
                        if len(lstIntersectingB) != 0:
                            intB = QgsGeometry.unaryUnion(lstIntersectingB)
                            diff_geom = diff_geom.difference(intB)

                        if diff_geom.wkbType() == 0:
                            temp_list = diff_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    diff_geom = QgsGeometry(i)
                        outFeat.setGeometry(diff_geom)
                        outFeat.setAttributes(atMapA)
                        writer.addFeature(outFeat)
                except Exception as err:
                        raise GeoAlgorithmExecutionException(
                            self.tr('Feature exception while computing union'))

        length = len(vproviderA.fields())

        featuresA = vector.features(vlayerB)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 100)
            add = False
            geom = QgsGeometry(inFeatA.geometry())
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(inFeatA.attributes())
            intersects = indexB.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except Exception as err:
                    raise GeoAlgorithmExecutionException(
                        self.tr('Feature exception while computing union'))
            else:
                for id in intersects:
                    request = QgsFeatureRequest().setFilterFid(id)
                    inFeatB = vlayerA.getFeatures(request).next()
                    atMapB = inFeatB.attributes()
                    tmpGeom = QgsGeometry(inFeatB.geometry())
                    try:
                        if diff_geom.intersects(tmpGeom):
                            add = True
                            diff_geom = QgsGeometry(
                                diff_geom.difference(tmpGeom))
                        else:
                            # Ihis only happends if the bounding box
                            # intersects, but the geometry doesn't
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            writer.addFeature(outFeat)
                    except Exception as err:
                        raise GeoAlgorithmExecutionException(
                            self.tr('Geometry exception while computing intersection'))

            if add:
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except Exception as err:
                    raise err
                    FEATURE_EXCEPT = False
            nElement += 1

        del writer
        if not GEOS_EXCEPT:
            ProcessingLog.addToLog(ProcessingLog.LOG_WARNING,
                                   self.tr('Geometry exception while computing intersection'))
        if not FEATURE_EXCEPT:
            ProcessingLog.addToLog(ProcessingLog.LOG_WARNING,
                                   self.tr('Feature exception while computing intersection'))
Example #20
0
    def processAlgorithm(self, parameters, context, feedback):
        expr_context = self.createExpressionContext(parameters, context, self.source)
        self.group_by_expr.prepare(expr_context)

        # Group features in memory layers
        source = self.source
        count = self.source.featureCount()
        if count:
            progress_step = 50.0 / count
        current = 0
        groups = {}
        keys = []  # We need deterministic order for the tests
        feature = QgsFeature()
        for feature in self.source.getFeatures():
            expr_context.setFeature(feature)
            group_by_value = self.evaluateExpression(self.group_by_expr, expr_context)

            # Get an hashable key for the dict
            key = group_by_value
            if isinstance(key, list):
                key = tuple(key)

            group = groups.get(key, None)
            if group is None:
                sink, id = QgsProcessingUtils.createFeatureSink(
                    'memory:',
                    context,
                    source.fields(),
                    source.wkbType(),
                    source.sourceCrs())
                layer = QgsProcessingUtils.mapLayerFromString(id, context)
                group = {
                    'sink': sink,
                    'layer': layer,
                    'feature': feature
                }
                groups[key] = group
                keys.append(key)

            group['sink'].addFeature(feature, QgsFeatureSink.FastInsert)

            current += 1
            feedback.setProgress(int(current * progress_step))
            if feedback.isCanceled():
                return

        (sink, dest_id) = self.parameterAsSink(parameters,
                                               self.OUTPUT,
                                               context,
                                               self.fields,
                                               QgsWkbTypes.multiType(source.wkbType()),
                                               source.sourceCrs())
        if sink is None:
            raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))

        # Calculate aggregates on memory layers
        if len(keys):
            progress_step = 50.0 / len(keys)
        for current, key in enumerate(keys):
            group = groups[key]
            expr_context = self.createExpressionContext(parameters, context)
            expr_context.appendScope(QgsExpressionContextUtils.layerScope(group['layer']))
            expr_context.setFeature(group['feature'])

            geometry = self.evaluateExpression(self.geometry_expr, expr_context)
            if geometry is not None and not geometry.isEmpty():
                geometry = QgsGeometry.unaryUnion(geometry.asGeometryCollection())
                if geometry.isEmpty():
                    raise QgsProcessingException(
                        'Impossible to combine geometries for {} = {}'
                        .format(self.group_by, group_by_value))

            attrs = []
            for fields_expr in self.fields_expr:
                attrs.append(self.evaluateExpression(fields_expr, expr_context))

            # Write output feature
            outFeat = QgsFeature()
            if geometry is not None:
                outFeat.setGeometry(geometry)
            outFeat.setAttributes(attrs)
            sink.addFeature(outFeat, QgsFeatureSink.FastInsert)

            feedback.setProgress(50 + int(current * progress_step))
            if feedback.isCanceled():
                return

        return {self.OUTPUT: dest_id}
Example #21
0
    def processAlgorithm(self, progress):
        vlayerA = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT))
        vlayerB = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT2))

        geomType = vlayerA.wkbType()
        fields = vector.combineVectorFields(vlayerA, vlayerB)
        writer = self.getOutputFromName(Union.OUTPUT).getVectorWriter(fields, geomType, vlayerA.crs())
        inFeatA = QgsFeature()
        inFeatB = QgsFeature()
        outFeat = QgsFeature()
        indexA = vector.spatialindex(vlayerB)
        indexB = vector.spatialindex(vlayerA)

        count = 0
        nElement = 0
        featuresA = vector.features(vlayerA)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 50)
            nElement += 1
            lstIntersectingB = []
            geom = inFeatA.geometry()
            atMapA = inFeatA.attributes()
            intersects = indexA.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    ProcessingLog.addToLog(
                        ProcessingLog.LOG_INFO,
                        self.tr("Feature geometry error: One or more output features ignored due to invalid geometry."),
                    )
            else:
                request = QgsFeatureRequest().setFilterFids(intersects)

                engine = QgsGeometry.createGeometryEngine(geom.geometry())
                engine.prepareGeometry()

                for inFeatB in vlayerB.getFeatures(request):
                    count += 1

                    atMapB = inFeatB.attributes()
                    tmpGeom = inFeatB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if not int_geom:
                            # There was a problem creating the intersection
                            ProcessingLog.addToLog(
                                ProcessingLog.LOG_INFO,
                                self.tr("GEOS geoprocessing error: One or more input features have invalid geometry."),
                            )
                            int_geom = QgsGeometry()
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if (
                            int_geom.wkbType() == QgsWkbTypes.Unknown
                            or QgsWkbTypes.flatType(int_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection
                        ):
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                                    try:
                                        outFeat.setGeometry(int_geom)
                                        outFeat.setAttributes(atMapA + atMapB)
                                        writer.addFeature(outFeat)
                                    except:
                                        ProcessingLog.addToLog(
                                            ProcessingLog.LOG_INFO,
                                            self.tr(
                                                "Feature geometry error: One or more output features ignored due to invalid geometry."
                                            ),
                                        )
                        else:
                            # Geometry list: prevents writing error
                            # in geometries of different types
                            # produced by the intersection
                            # fix #3549
                            if int_geom.wkbType() in wkbTypeGroups[wkbTypeGroups[int_geom.wkbType()]]:
                                try:
                                    outFeat.setGeometry(int_geom)
                                    outFeat.setAttributes(atMapA + atMapB)
                                    writer.addFeature(outFeat)
                                except:
                                    ProcessingLog.addToLog(
                                        ProcessingLog.LOG_INFO,
                                        self.tr(
                                            "Feature geometry error: One or more output features ignored due to invalid geometry."
                                        ),
                                    )

                # the remaining bit of inFeatA's geometry
                # if there is nothing left, this will just silently fail and we're good
                diff_geom = QgsGeometry(geom)
                if len(lstIntersectingB) != 0:
                    intB = QgsGeometry.unaryUnion(lstIntersectingB)
                    diff_geom = diff_geom.difference(intB)
                    if diff_geom.isGeosEmpty() or not diff_geom.isGeosValid():
                        ProcessingLog.addToLog(
                            ProcessingLog.LOG_ERROR,
                            self.tr("GEOS geoprocessing error: One or more input features have invalid geometry."),
                        )

                if (
                    diff_geom.wkbType() == 0
                    or QgsWkbTypes.flatType(diff_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection
                ):
                    temp_list = diff_geom.asGeometryCollection()
                    for i in temp_list:
                        if i.type() == geom.type():
                            diff_geom = QgsGeometry(i)
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(
                        ProcessingLog.LOG_INFO,
                        self.tr("Feature geometry error: One or more output features ignored due to invalid geometry."),
                    )

        length = len(vlayerA.fields())
        atMapA = [None] * length

        featuresA = vector.features(vlayerB)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 100)
            add = False
            geom = inFeatA.geometry()
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(inFeatA.attributes())
            intersects = indexB.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(
                        ProcessingLog.LOG_INFO,
                        self.tr("Feature geometry error: One or more output features ignored due to invalid geometry."),
                    )
            else:
                request = QgsFeatureRequest().setFilterFids(intersects)

                # use prepared geometries for faster intersection tests
                engine = QgsGeometry.createGeometryEngine(diff_geom.geometry())
                engine.prepareGeometry()

                for inFeatB in vlayerA.getFeatures(request):
                    atMapB = inFeatB.attributes()
                    tmpGeom = inFeatB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        add = True
                        diff_geom = QgsGeometry(diff_geom.difference(tmpGeom))
                        if diff_geom.isGeosEmpty() or not diff_geom.isGeosValid():
                            ProcessingLog.addToLog(
                                ProcessingLog.LOG_ERROR,
                                self.tr("GEOS geoprocessing error: One or more input features have invalid geometry."),
                            )
                    else:
                        try:
                            # Ihis only happends if the bounding box
                            # intersects, but the geometry doesn't
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            writer.addFeature(outFeat)
                        except:
                            ProcessingLog.addToLog(
                                ProcessingLog.LOG_INFO,
                                self.tr(
                                    "Feature geometry error: One or more output features ignored due to invalid geometry."
                                ),
                            )

            if add:
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(
                        ProcessingLog.LOG_INFO,
                        self.tr("Feature geometry error: One or more output features ignored due to invalid geometry."),
                    )
            nElement += 1

        del writer
Example #22
0
def clip(layer_to_clip, mask_layer, callback=None):
    """Clip a vector layer with another.

    Issue https://github.com/inasafe/inasafe/issues/3186

    Note : This algorithm is copied from :
    https://github.com/qgis/QGIS/blob/master/python/plugins/processing/algs/
    qgis/Clip.py

    :param layer_to_clip: The vector layer to clip.
    :type layer_to_clip: QgsVectorLayer

    :param mask_layer: The vector layer to use for clipping.
    :type mask_layer: QgsVectorLayer

    :param callback: A function to all to indicate progress. The function
        should accept params 'current' (int), 'maximum' (int) and 'step' (str).
        Defaults to None.
    :type callback: function

    :return: The clip vector layer.
    :rtype: QgsVectorLayer

    .. versionadded:: 4.0
    """
    output_layer_name = clip_steps['output_layer_name']
    output_layer_name = output_layer_name % (
        layer_to_clip.keywords['layer_purpose'])
    processing_step = clip_steps['step_name']

    writer = create_memory_layer(
        output_layer_name,
        layer_to_clip.geometryType(),
        layer_to_clip.crs(),
        layer_to_clip.fields()
    )
    writer.startEditing()

    # Begin copy/paste from Processing plugin.
    # Please follow their code as their code is optimized.
    # The code below is not following our coding standards because we want to
    # be able to track any diffs from QGIS easily.

    # first build up a list of clip geometries
    clip_geometries = []
    request = QgsFeatureRequest().setSubsetOfAttributes([])
    for mask_feature in mask_layer.getFeatures(request):
        clip_geometries.append(QgsGeometry(mask_feature.geometry()))

    # are we clipping against a single feature? if so,
    # we can show finer progress reports
    if len(clip_geometries) > 1:
        # noinspection PyTypeChecker,PyCallByClass,PyArgumentList
        combined_clip_geom = QgsGeometry.unaryUnion(clip_geometries)
        single_clip_feature = False
    else:
        combined_clip_geom = clip_geometries[0]
        single_clip_feature = True

    # use prepared geometries for faster intersection tests
    # noinspection PyArgumentList
    engine = QgsGeometry.createGeometryEngine(combined_clip_geom.geometry())
    engine.prepareGeometry()

    tested_feature_ids = set()

    for i, clip_geom in enumerate(clip_geometries):
        request = QgsFeatureRequest().setFilterRect(clip_geom.boundingBox())
        input_features = [f for f in layer_to_clip.getFeatures(request)]

        if not input_features:
            continue

        if single_clip_feature:
            total = 100.0 / len(input_features)
        else:
            total = 0

        for current, in_feat in enumerate(input_features):
            if not in_feat.geometry():
                continue

            if in_feat.id() in tested_feature_ids:
                # don't retest a feature we have already checked
                continue

            tested_feature_ids.add(in_feat.id())

            if not engine.intersects(in_feat.geometry().geometry()):
                continue

            if not engine.contains(in_feat.geometry().geometry()):
                cur_geom = in_feat.geometry()
                new_geom = combined_clip_geom.intersection(cur_geom)
                if new_geom.wkbType() == QgsWKBTypes.Unknown \
                        or QgsWKBTypes.flatType(
                            new_geom.geometry().wkbType()) == \
                                QgsWKBTypes.GeometryCollection:
                    int_com = in_feat.geometry().combine(new_geom)
                    int_sym = in_feat.geometry().symDifference(new_geom)
                    if not int_com or not int_sym:
                        # LOGGER.debug(
                        #     tr('GEOS geoprocessing error: One or more input '
                        #        'features have invalid geometry.'))
                        pass
                    else:
                        new_geom = int_com.difference(int_sym)
                        if new_geom.isGeosEmpty()\
                                or not new_geom.isGeosValid():
                            # LOGGER.debug(
                            #     tr('GEOS geoprocessing error: One or more '
                            #        'input features have invalid geometry.'))
                            pass
            else:
                # clip geometry totally contains feature geometry,
                # so no need to perform intersection
                new_geom = in_feat.geometry()

            try:
                out_feat = QgsFeature()
                out_feat.setGeometry(new_geom)
                out_feat.setAttributes(in_feat.attributes())
                if new_geom.type() == layer_to_clip.geometryType():
                    writer.addFeature(out_feat)
            except:
                LOGGER.debug(
                    tr('Feature geometry error: One or more output features '
                       'ignored due to invalid geometry.'))
                continue

            # TODO implement callback
            if single_clip_feature:
                # progress.setPercentage(int(current * total))
                pass

        if not single_clip_feature:
            # coarse progress report for multiple clip geometries
            # progress.setPercentage(100.0 * i / len(clip_geoms))
            pass

    # End copy/paste from Processing plugin.
    writer.commitChanges()

    writer.keywords = layer_to_clip.keywords.copy()
    writer.keywords['title'] = output_layer_name
    check_layer(writer)
    return writer
Example #23
0
    def processAlgorithm(self, parameters, context, feedback):
        source = self.parameterAsSource(parameters, self.INPUT, context)
        if source is None:
            raise QgsProcessingException(
                self.invalidSourceError(parameters, self.INPUT))

        if self.parameterAsBool(parameters, self.KEEP_FIELDS, context):
            fields = source.fields()
        else:
            fields = QgsFields()

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT,
                                               context, fields,
                                               QgsWkbTypes.Polygon,
                                               source.sourceCrs())
        if sink is None:
            raise QgsProcessingException(
                self.invalidSinkError(parameters, self.OUTPUT))

        allLinesList = []
        features = source.getFeatures(
            QgsFeatureRequest().setSubsetOfAttributes([]))
        feedback.pushInfo(
            QCoreApplication.translate('Polygonize', 'Processing lines…'))
        total = (40.0 / source.featureCount()) if source.featureCount() else 1
        for current, inFeat in enumerate(features):
            if feedback.isCanceled():
                break

            if inFeat.geometry():
                allLinesList.append(inFeat.geometry())
            feedback.setProgress(int(current * total))

        feedback.setProgress(40)

        feedback.pushInfo(
            QCoreApplication.translate('Polygonize', 'Noding lines…'))
        allLines = QgsGeometry.unaryUnion(allLinesList)
        if feedback.isCanceled():
            return {}

        feedback.setProgress(45)
        feedback.pushInfo(
            QCoreApplication.translate('Polygonize', 'Polygonizing…'))
        polygons = QgsGeometry.polygonize([allLines])
        if polygons.isEmpty():
            feedback.reportError(self.tr('No polygons were created!'))
        feedback.setProgress(50)

        if not polygons.isEmpty():
            feedback.pushInfo(
                QCoreApplication.translate('Polygonize', 'Saving polygons…'))
            total = 50.0 / polygons.constGet().numGeometries()
            for i in range(polygons.constGet().numGeometries()):
                if feedback.isCanceled():
                    break

                outFeat = QgsFeature()
                geom = QgsGeometry(polygons.constGet().geometryN(i).clone())
                outFeat.setGeometry(geom)
                sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                feedback.setProgress(50 + int(current * total))

        return {self.OUTPUT: dest_id}
    def get_gaps_in_polygon_layer(self, layer, include_roads):
        """
        Find gaps in a continuous layer in space.

        Ported/adapted to Python from:
        https://github.com/qgis/QGIS/blob/2c536307476e205b83d86863b903d7ea9d628f0d/src/plugins/topology/topolTest.cpp#L579-L726
        """
        request = QgsFeatureRequest().setSubsetOfAttributes([])
        features = layer.getFeatures(request)
        featureCollection = list()

        for feature in features:
            if feature.geometry().isEmpty():
                continue

            if not feature.geometry().isGeosValid():
                continue

            if feature.geometry().isMultipart() and feature.geometry().type(
            ) == QgsWkbTypes.PolygonGeometry:
                for polygon in feature.geometry().asMultiPolygon():
                    featureCollection.append(
                        QgsGeometry.fromPolygonXY(polygon))
                continue

            featureCollection.append(feature.geometry())

        union_geom = QgsGeometry.unaryUnion(featureCollection)
        aux_convex_hull = union_geom.convexHull()
        buffer_extent = QgsGeometry.fromRect(union_geom.boundingBox()).buffer(
            2, 3)
        buffer_diff = buffer_extent.difference(
            QgsGeometry.fromRect(union_geom.boundingBox()))
        diff_geoms = buffer_extent.difference(union_geom).difference(
            buffer_diff)

        if not diff_geoms:
            return None

        feature_error = list()
        if not diff_geoms.isMultipart():
            if include_roads and diff_geoms.touches(
                    union_geom) and diff_geoms.intersects(buffer_diff):
                print("Unique value and no error")
                return None

        for geometry in diff_geoms.asMultiPolygon():
            conflict_geom = QgsGeometry.fromPolygonXY(geometry)
            if not include_roads and conflict_geom.touches(
                    union_geom) and conflict_geom.intersects(buffer_diff):
                continue

            if not union_geom.isMultipart() and conflict_geom.touches(
                    union_geom) and conflict_geom.intersects(buffer_diff):
                continue

            feature_error.append(conflict_geom)

        unified_error = QgsGeometry.collectGeometry(feature_error)
        feature_error.clear()
        clean_errors = unified_error.intersection(aux_convex_hull)

        return self.extract_geoms_by_type(clean_errors,
                                          [QgsWkbTypes.PolygonGeometry])
Example #25
0
def buffering(progress, writer, distance, field, useField, layer, dissolve,
              segments, endCapStyle=1, joinStyle=1, mitreLimit=2):

    if useField:
        field = layer.fieldNameIndex(field)

    outFeat = QgsFeature()

    current = 0
    features = vector.features(layer)
    total = 100.0 / float(len(features))

    # With dissolve
    if dissolve:
        first = True
        buffered_geometries = []
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance

            inGeom = inFeat.geometry()
            if not inGeom:
                ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, 'Feature {} has empty geometry. Skipping...'.format(inFeat.id()))
                continue
            if not inGeom.isGeosValid():
                ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, 'Feature {} has invalid geometry. Skipping...'.format(inFeat.id()))
                continue
            buffered_geometries.append(inGeom.buffer(float(value), segments, endCapStyle, joinStyle, mitreLimit))

            current += 1
            progress.setPercentage(int(current * total))

        final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
        outFeat.setGeometry(final_geometry)
        outFeat.setAttributes(attrs)
        writer.addFeature(outFeat)
    else:
        # Without dissolve
        for inFeat in features:
            attrs = inFeat.attributes()
            if useField:
                value = attrs[field]
            else:
                value = distance
            inGeom = inFeat.geometry()
            outFeat = QgsFeature()
            if inGeom.isEmpty() or inGeom.isGeosEmpty():
                pass
            elif not inGeom.isGeosValid():
                ProcessingLog.addToLog(ProcessingLog.LOG_WARNING, 'Feature {} has invalid geometry. Skipping...'.format(inFeat.id()))
                continue
            else:
                outGeom = inGeom.buffer(float(value), segments, endCapStyle, joinStyle, mitreLimit)
                outFeat.setGeometry(outGeom)
            outFeat.setAttributes(attrs)
            writer.addFeature(outFeat)
            current += 1
            progress.setPercentage(int(current * total))

    del writer
Example #26
0
File: Union.py Project: cjmayo/QGIS
    def processAlgorithm(self, progress):
        vlayerA = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT))
        vlayerB = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT2))
        GEOS_EXCEPT = True
        FEATURE_EXCEPT = True
        vproviderA = vlayerA.dataProvider()

        fields = vector.combineVectorFields(vlayerA, vlayerB)
        names = [field.name() for field in fields]
        ProcessingLog.addToLog(ProcessingLog.LOG_INFO, unicode(names))
        writer = self.getOutputFromName(Union.OUTPUT).getVectorWriter(fields,
                                                                      vproviderA.geometryType(), vproviderA.crs())
        inFeatA = QgsFeature()
        inFeatB = QgsFeature()
        outFeat = QgsFeature()
        indexA = vector.spatialindex(vlayerB)
        indexB = vector.spatialindex(vlayerA)

        count = 0
        nElement = 0
        featuresA = vector.features(vlayerA)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 50)
            nElement += 1
            lstIntersectingB = []
            geom = QgsGeometry(inFeatA.geometry())
            atMapA = inFeatA.attributes()
            intersects = indexA.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    raise GeoAlgorithmExecutionException(
                        self.tr('Feature exception while computing union'))
            else:
                for id in intersects:
                    count += 1
                    request = QgsFeatureRequest().setFilterFid(id)
                    inFeatB = vlayerB.getFeatures(request).next()
                    atMapB = inFeatB.attributes()
                    tmpGeom = QgsGeometry(inFeatB.geometry())

                    if geom.intersects(tmpGeom):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if int_geom is None:
                           # There was a problem creating the intersection
                            raise GeoAlgorithmExecutionException(
                                self.tr('Geometry exception while computing '
                                        'intersection'))
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if int_geom.wkbType() == QGis.WKBUnknown or QgsWKBTypes.flatType(int_geom.geometry().wkbType()) == QgsWKBTypes.GeometryCollection:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                        try:
                            outFeat.setGeometry(int_geom)
                            attrs = []
                            attrs.extend(atMapA)
                            attrs.extend(atMapB)
                            outFeat.setAttributes(attrs)
                            writer.addFeature(outFeat)
                        except Exception as err:
                            raise GeoAlgorithmExecutionException(
                                self.tr('Feature exception while computing union'))

                try:
                    # the remaining bit of inFeatA's geometry
                    # if there is nothing left, this will just silently fail and we're good
                    diff_geom = QgsGeometry(geom)
                    if len(lstIntersectingB) != 0:
                        intB = QgsGeometry.unaryUnion(lstIntersectingB)
                        diff_geom = diff_geom.difference(intB)

                    if diff_geom.wkbType() == 0 or QgsWKBTypes.flatType(int_geom.geometry().wkbType()) == QgsWKBTypes.GeometryCollection:
                        temp_list = diff_geom.asGeometryCollection()
                        for i in temp_list:
                            if i.type() == geom.type():
                                diff_geom = QgsGeometry(i)
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except Exception as err:
                    raise GeoAlgorithmExecutionException(
                        self.tr('Feature exception while computing union'))

        length = len(vproviderA.fields())

        featuresA = vector.features(vlayerB)
        nFeat = len(featuresA)
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 100)
            add = False
            geom = QgsGeometry(inFeatA.geometry())
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(inFeatA.attributes())
            intersects = indexB.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except Exception as err:
                    raise GeoAlgorithmExecutionException(
                        self.tr('Feature exception while computing union'))
            else:
                for id in intersects:
                    request = QgsFeatureRequest().setFilterFid(id)
                    inFeatB = vlayerA.getFeatures(request).next()
                    atMapB = inFeatB.attributes()
                    tmpGeom = QgsGeometry(inFeatB.geometry())
                    try:
                        if diff_geom.intersects(tmpGeom):
                            add = True
                            diff_geom = QgsGeometry(
                                diff_geom.difference(tmpGeom))
                        else:
                            # Ihis only happends if the bounding box
                            # intersects, but the geometry doesn't
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            writer.addFeature(outFeat)
                    except Exception as err:
                        raise GeoAlgorithmExecutionException(
                            self.tr('Geometry exception while computing intersection'))

            if add:
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat)
                except Exception as err:
                    raise err
                    FEATURE_EXCEPT = False
            nElement += 1

        del writer
        if not GEOS_EXCEPT:
            ProcessingLog.addToLog(ProcessingLog.LOG_WARNING,
                                   self.tr('Geometry exception while computing intersection'))
        if not FEATURE_EXCEPT:
            ProcessingLog.addToLog(ProcessingLog.LOG_WARNING,
                                   self.tr('Feature exception while computing intersection'))
Example #27
0
    def processAlgorithm(self, progress):
        source_layer = dataobjects.getObjectFromUri(
            self.getParameterValue(Clip.INPUT))
        mask_layer = dataobjects.getObjectFromUri(
            self.getParameterValue(Clip.OVERLAY))

        writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
            source_layer.fields(),
            QgsWkbTypes.multiType(source_layer.wkbType()),
            source_layer.crs())

        # first build up a list of clip geometries
        clip_geoms = []
        for maskFeat in vector.features(mask_layer, QgsFeatureRequest().setSubsetOfAttributes([])):
            clip_geoms.append(maskFeat.geometry())

        # are we clipping against a single feature? if so, we can show finer progress reports
        if len(clip_geoms) > 1:
            combined_clip_geom = QgsGeometry.unaryUnion(clip_geoms)
            single_clip_feature = False
        else:
            combined_clip_geom = clip_geoms[0]
            single_clip_feature = True

        # use prepared geometries for faster intersection tests
        engine = QgsGeometry.createGeometryEngine(combined_clip_geom.geometry())
        engine.prepareGeometry()

        tested_feature_ids = set()

        for i, clip_geom in enumerate(clip_geoms):
            input_features = [f for f in vector.features(source_layer, QgsFeatureRequest().setFilterRect(clip_geom.boundingBox()))]

            if not input_features:
                continue

            if single_clip_feature:
                total = 100.0 / len(input_features)
            else:
                total = 0

            for current, in_feat in enumerate(input_features):
                if not in_feat.geometry():
                    continue

                if in_feat.id() in tested_feature_ids:
                    # don't retest a feature we have already checked
                    continue

                tested_feature_ids.add(in_feat.id())

                if not engine.intersects(in_feat.geometry().geometry()):
                    continue

                if not engine.contains(in_feat.geometry().geometry()):
                    cur_geom = in_feat.geometry()
                    new_geom = combined_clip_geom.intersection(cur_geom)
                    if new_geom.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(new_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                        int_com = in_feat.geometry().combine(new_geom)
                        int_sym = in_feat.geometry().symDifference(new_geom)
                        if not int_com or not int_sym:
                            ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                                   self.tr('GEOS geoprocessing error: One or more '
                                                           'input features have invalid geometry.'))
                        else:
                            new_geom = int_com.difference(int_sym)
                            if new_geom.isGeosEmpty() or not new_geom.isGeosValid():
                                ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                                       self.tr('GEOS geoprocessing error: One or more '
                                                               'input features have invalid geometry.'))
                else:
                    # clip geometry totally contains feature geometry, so no need to perform intersection
                    new_geom = in_feat.geometry()

                try:
                    out_feat = QgsFeature()
                    out_feat.setGeometry(new_geom)
                    out_feat.setAttributes(in_feat.attributes())
                    writer.addFeature(out_feat)
                except:
                    ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                           self.tr('Feature geometry error: One or more '
                                                   'output features ignored due to '
                                                   'invalid geometry.'))
                    continue

                if single_clip_feature:
                    progress.setPercentage(int(current * total))

            if not single_clip_feature:
                # coarse progress report for multiple clip geometries
                progress.setPercentage(100.0 * i / len(clip_geoms))

        del writer
Example #28
0
    def processAlgorithm(self, progress):
        vlayerA = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT))
        vlayerB = dataobjects.getObjectFromUri(self.getParameterValue(Union.INPUT2))

        geomType = vlayerA.wkbType()
        fields = vector.combineVectorFields(vlayerA, vlayerB)
        writer = self.getOutputFromName(Union.OUTPUT).getVectorWriter(fields,
                                                                      geomType,
                                                                      vlayerA.crs())
        inFeatA = QgsFeature()
        inFeatB = QgsFeature()
        outFeat = QgsFeature()
        indexA = vector.spatialindex(vlayerB)
        indexB = vector.spatialindex(vlayerA)

        count = 0
        nElement = 0
        featuresA = vector.features(vlayerA)
        nFeat = len(featuresA) if len(featuresA) > 0 else 1
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 50)
            nElement += 1
            lstIntersectingB = []
            geom = QgsGeometry(inFeatA.geometry())
            atMapA = inFeatA.attributes()
            intersects = indexA.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            else:
                for id in intersects:
                    count += 1
                    request = QgsFeatureRequest().setFilterFid(id)
                    inFeatB = vlayerB.getFeatures(request).next()
                    atMapB = inFeatB.attributes()
                    tmpGeom = QgsGeometry(inFeatB.geometry())

                    if geom.intersects(tmpGeom):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if int_geom is None:
                            # There was a problem creating the intersection
                            ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                   self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))
                            int_geom = QgsGeometry()
                        else:
                            int_geom = QgsGeometry(int_geom)

                        # TODO: the result may have a different dimension (e.g. intersection of two polygons may result in a single point)
                        # or the result may be a collection of geometries (e.g. intersection of two polygons results in three polygons and one linestring).
                        # We need to filter out all acceptable geometries into a single (possibly multi-part) geometry - and we need
                        # to do it consistently also in the code further below

                        if int_geom.wkbType() == QGis.WKBUnknown or QgsWKBTypes.flatType(int_geom.geometry().wkbType()) == QgsWKBTypes.GeometryCollection:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                                    try:
                                        outFeat.setGeometry(int_geom)
                                        outFeat.setAttributes(atMapA + atMapB)
                                        writer.addFeature(outFeat)
                                    except:
                                        ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                               self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
                        else:
                            # Geometry list: prevents writing error
                            # in geometries of different types
                            # produced by the intersection
                            # fix #3549
                            if int_geom.wkbType() in wkbTypeGroups[wkbTypeGroups[int_geom.wkbType()]]:
                                try:
                                    outFeat.setGeometry(int_geom)
                                    outFeat.setAttributes(atMapA + atMapB)
                                    writer.addFeature(outFeat)
                                except:
                                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

                # the remaining bit of inFeatA's geometry
                # if there is nothing left, this will just silently fail and we're good
                diff_geom = QgsGeometry(geom)
                if len(lstIntersectingB) != 0:
                    intB = QgsGeometry.unaryUnion(lstIntersectingB)
                    diff_geom = diff_geom.difference(intB)
                    if diff_geom is None:
                        ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                               self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))
                        diff_geom = QgsGeometry()
                    if diff_geom.isGeosEmpty() or not diff_geom.isGeosValid():
                        ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                               self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))

                # TODO: correctly handly different output geometry types (see todo above)
                if diff_geom.wkbType() == 0 or QgsWKBTypes.flatType(diff_geom.geometry().wkbType()) == QgsWKBTypes.GeometryCollection:
                    temp_list = diff_geom.asGeometryCollection()
                    for i in temp_list:
                        if i.type() == geom.type():
                            diff_geom = QgsGeometry(i)
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat)
                except:
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

        length = len(vlayerA.fields())
        atMapA = [None] * length

        featuresA = vector.features(vlayerB)
        nFeat = len(featuresA) if len(featuresA) else 1
        for inFeatA in featuresA:
            progress.setPercentage(nElement / float(nFeat) * 100)
            add = False
            geom = QgsGeometry(inFeatA.geometry())
            atMap = [None] * length
            atMap.extend(inFeatA.attributes())
            intersects = indexB.intersects(geom.boundingBox())
            lstIntersectingA = []

            for id in intersects:
                request = QgsFeatureRequest().setFilterFid(id)
                inFeatB = vlayerA.getFeatures(request).next()
                atMapB = inFeatB.attributes()
                tmpGeom = QgsGeometry(inFeatB.geometry())

                if geom.intersects(tmpGeom):
                    lstIntersectingA.append(tmpGeom)

            if len(lstIntersectingA) == 0:
                res_geom = geom
            else:
                intA = QgsGeometry.unaryUnion(lstIntersectingA)
                res_geom = geom.difference(intA)
                if res_geom is None:
                    ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                           self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))
                    res_geom = QgsGeometry()
                if res_geom.isGeosEmpty() or not res_geom.isGeosValid():
                    ProcessingLog.addToLog(ProcessingLog.LOG_ERROR,
                                           self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'))

            # TODO: correctly handly different output geometry types (see todo above)

            try:
                outFeat.setGeometry(res_geom)
                outFeat.setAttributes(atMap)
                writer.addFeature(outFeat)
            except:
                ProcessingLog.addToLog(ProcessingLog.LOG_INFO,
                                       self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            nElement += 1

        del writer
Example #29
0
    def linearMatrix(self, parameters, context, source, inField, target_source, targetField, same_source_and_target,
                     matType, nPoints, feedback):

        if same_source_and_target:
            # need to fetch an extra point from the index, since the closest match will always be the same
            # as the input feature
            nPoints += 1

        inIdx = source.fields().lookupField(inField)
        outIdx = target_source.fields().lookupField(targetField)

        fields = QgsFields()
        input_id_field = source.fields()[inIdx]
        input_id_field.setName('InputID')
        fields.append(input_id_field)
        if matType == 0:
            target_id_field = target_source.fields()[outIdx]
            target_id_field.setName('TargetID')
            fields.append(target_id_field)
            fields.append(QgsField('Distance', QVariant.Double))
        else:
            fields.append(QgsField('MEAN', QVariant.Double))
            fields.append(QgsField('STDDEV', QVariant.Double))
            fields.append(QgsField('MIN', QVariant.Double))
            fields.append(QgsField('MAX', QVariant.Double))

        out_wkb = QgsWkbTypes.multiType(source.wkbType()) if matType == 0 else source.wkbType()
        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
                                               fields, out_wkb, source.sourceCrs())
        if sink is None:
            raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))

        index = QgsSpatialIndex(target_source.getFeatures(QgsFeatureRequest().setSubsetOfAttributes([]).setDestinationCrs(source.sourceCrs(), context.transformContext())), feedback)

        distArea = QgsDistanceArea()
        distArea.setSourceCrs(source.sourceCrs(), context.transformContext())
        distArea.setEllipsoid(context.project().ellipsoid())

        features = source.getFeatures(QgsFeatureRequest().setSubsetOfAttributes([inIdx]))
        total = 100.0 / source.featureCount() if source.featureCount() else 0
        for current, inFeat in enumerate(features):
            if feedback.isCanceled():
                break

            inGeom = inFeat.geometry()
            inID = str(inFeat.attributes()[inIdx])
            featList = index.nearestNeighbor(inGeom.asPoint(), nPoints)
            distList = []
            vari = 0.0
            request = QgsFeatureRequest().setFilterFids(featList).setSubsetOfAttributes([outIdx]).setDestinationCrs(source.sourceCrs(), context.transformContext())
            for outFeat in target_source.getFeatures(request):
                if feedback.isCanceled():
                    break

                if same_source_and_target and inFeat.id() == outFeat.id():
                    continue

                outID = outFeat.attributes()[outIdx]
                outGeom = outFeat.geometry()
                dist = distArea.measureLine(inGeom.asPoint(),
                                            outGeom.asPoint())

                if matType == 0:
                    out_feature = QgsFeature()
                    out_geom = QgsGeometry.unaryUnion([inFeat.geometry(), outFeat.geometry()])
                    out_feature.setGeometry(out_geom)
                    out_feature.setAttributes([inID, outID, dist])
                    sink.addFeature(out_feature, QgsFeatureSink.FastInsert)
                else:
                    distList.append(float(dist))

            if matType != 0:
                mean = sum(distList) / len(distList)
                for i in distList:
                    vari += (i - mean) * (i - mean)
                vari = math.sqrt(vari / len(distList))

                out_feature = QgsFeature()
                out_feature.setGeometry(inFeat.geometry())
                out_feature.setAttributes([inID, mean, vari, min(distList), max(distList)])
                sink.addFeature(out_feature, QgsFeatureSink.FastInsert)

            feedback.setProgress(int(current * total))

        return {self.OUTPUT: dest_id}
Example #30
0
File: Union.py Project: ndavid/QGIS
    def processAlgorithm(self, parameters, context, feedback):
        vlayerA = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(Union.INPUT), context)
        vlayerB = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(Union.INPUT2), context)

        geomType = vlayerA.wkbType()
        fields = vector.combineFields(vlayerA.fields(), vlayerB.fields())
        writer = self.getOutputFromName(Union.OUTPUT).getVectorWriter(fields, geomType, vlayerA.crs(), context)
        inFeatA = QgsFeature()
        inFeatB = QgsFeature()
        outFeat = QgsFeature()
        indexA = QgsProcessingUtils.createSpatialIndex(vlayerB, context)
        indexB = QgsProcessingUtils.createSpatialIndex(vlayerA, context)

        count = 0
        nElement = 0
        featuresA = QgsProcessingUtils.getFeatures(vlayerA, context)
        nFeat = QgsProcessingUtils.featureCount(vlayerA, context)
        for inFeatA in featuresA:
            feedback.setProgress(nElement / float(nFeat) * 50)
            nElement += 1
            lstIntersectingB = []
            geom = inFeatA.geometry()
            atMapA = inFeatA.attributes()
            intersects = indexA.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                             self.tr('Processing'), QgsMessageLog.INFO)
            else:
                request = QgsFeatureRequest().setFilterFids(intersects)

                engine = QgsGeometry.createGeometryEngine(geom.geometry())
                engine.prepareGeometry()

                for inFeatB in vlayerB.getFeatures(request):
                    count += 1

                    atMapB = inFeatB.attributes()
                    tmpGeom = inFeatB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if not int_geom:
                            # There was a problem creating the intersection
                            QgsMessageLog.logMessage(self.tr('GEOS geoprocessing error: One or more input features have invalid geometry.'),
                                                     self.tr('Processing'), QgsMessageLog.INFO)
                            int_geom = QgsGeometry()
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if int_geom.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(int_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                                    try:
                                        outFeat.setGeometry(int_geom)
                                        outFeat.setAttributes(atMapA + atMapB)
                                        writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                                    except:
                                        QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                                                 self.tr('Processing'), QgsMessageLog.INFO)
                        else:
                            # Geometry list: prevents writing error
                            # in geometries of different types
                            # produced by the intersection
                            # fix #3549
                            if int_geom.wkbType() in wkbTypeGroups[wkbTypeGroups[int_geom.wkbType()]]:
                                try:
                                    outFeat.setGeometry(int_geom)
                                    outFeat.setAttributes(atMapA + atMapB)
                                    writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                                except:
                                    QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                                             self.tr('Processing'), QgsMessageLog.INFO)

                # the remaining bit of inFeatA's geometry
                # if there is nothing left, this will just silently fail and we're good
                diff_geom = QgsGeometry(geom)
                if len(lstIntersectingB) != 0:
                    intB = QgsGeometry.unaryUnion(lstIntersectingB)
                    diff_geom = diff_geom.difference(intB)

                if diff_geom.wkbType() == 0 or QgsWkbTypes.flatType(diff_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                    temp_list = diff_geom.asGeometryCollection()
                    for i in temp_list:
                        if i.type() == geom.type():
                            diff_geom = QgsGeometry(i)
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                             self.tr('Processing'), QgsMessageLog.INFO)

        length = len(vlayerA.fields())
        atMapA = [None] * length

        featuresA = QgsProcessingUtils.getFeatures(vlayerB, context)
        nFeat = QgsProcessingUtils.featureCount(vlayerB, context)
        for inFeatA in featuresA:
            feedback.setProgress(nElement / float(nFeat) * 100)
            add = False
            geom = inFeatA.geometry()
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(inFeatA.attributes())
            intersects = indexB.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                             self.tr('Processing'), QgsMessageLog.INFO)
            else:
                request = QgsFeatureRequest().setFilterFids(intersects)

                # use prepared geometries for faster intersection tests
                engine = QgsGeometry.createGeometryEngine(diff_geom.geometry())
                engine.prepareGeometry()

                for inFeatB in vlayerA.getFeatures(request):
                    atMapB = inFeatB.attributes()
                    tmpGeom = inFeatB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        add = True
                        diff_geom = QgsGeometry(diff_geom.difference(tmpGeom))
                    else:
                        try:
                            # Ihis only happens if the bounding box
                            # intersects, but the geometry doesn't
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                        except:
                            QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                                     self.tr('Processing'), QgsMessageLog.INFO)

            if add:
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    writer.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    QgsMessageLog.logMessage(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'),
                                             self.tr('Processing'), QgsMessageLog.INFO)
            nElement += 1

        del writer
Example #31
0
    def processAlgorithm(self, parameters, context, feedback):
        sourceA = self.parameterAsSource(parameters, self.INPUT, context)
        sourceB = self.parameterAsSource(parameters, self.OVERLAY, context)

        geomType = QgsWkbTypes.multiType(sourceA.wkbType())
        fields = vector.combineFields(sourceA.fields(), sourceB.fields())

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
                                               fields, geomType, sourceA.sourceCrs())

        featA = QgsFeature()
        featB = QgsFeature()
        outFeat = QgsFeature()

        indexA = QgsSpatialIndex(sourceA, feedback)
        indexB = QgsSpatialIndex(sourceB.getFeatures(QgsFeatureRequest().setSubsetOfAttributes([]).setDestinationCrs(sourceA.sourceCrs())), feedback)

        total = 100.0 / (sourceA.featureCount() * sourceB.featureCount()) if sourceA.featureCount() and sourceB.featureCount() else 1
        count = 0

        for featA in sourceA.getFeatures():
            if feedback.isCanceled():
                break

            lstIntersectingB = []
            geom = featA.geometry()
            atMapA = featA.attributes()
            intersects = indexB.intersects(geom.boundingBox())
            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMapA)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    # This really shouldn't happen, as we haven't
                    # edited the input geom at all
                    feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            else:
                request = QgsFeatureRequest().setFilterFids(intersects).setSubsetOfAttributes([])
                request.setDestinationCrs(sourceA.sourceCrs())

                engine = QgsGeometry.createGeometryEngine(geom.geometry())
                engine.prepareGeometry()

                for featB in sourceB.getFeatures(request):
                    atMapB = featB.attributes()
                    tmpGeom = featB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        int_geom = geom.intersection(tmpGeom)
                        lstIntersectingB.append(tmpGeom)

                        if not int_geom:
                            # There was a problem creating the intersection
                            feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
                            int_geom = QgsGeometry()
                        else:
                            int_geom = QgsGeometry(int_geom)

                        if int_geom.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(int_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                            # Intersection produced different geomety types
                            temp_list = int_geom.asGeometryCollection()
                            for i in temp_list:
                                if i.type() == geom.type():
                                    int_geom = QgsGeometry(i)
                                    try:
                                        outFeat.setGeometry(int_geom)
                                        outFeat.setAttributes(atMapA + atMapB)
                                        sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                                    except:
                                        feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
                        else:
                            # Geometry list: prevents writing error
                            # in geometries of different types
                            # produced by the intersection
                            # fix #3549
                            if int_geom.wkbType() in wkbTypeGroups[wkbTypeGroups[int_geom.wkbType()]]:
                                try:
                                    outFeat.setGeometry(int_geom)
                                    outFeat.setAttributes(atMapA + atMapB)
                                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                                except:
                                    feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

                # the remaining bit of featA's geometry
                # if there is nothing left, this will just silently fail and we're good
                diff_geom = QgsGeometry(geom)
                if len(lstIntersectingB) != 0:
                    intB = QgsGeometry.unaryUnion(lstIntersectingB)
                    diff_geom = diff_geom.difference(intB)

                if diff_geom.wkbType() == QgsWkbTypes.Unknown or QgsWkbTypes.flatType(diff_geom.geometry().wkbType()) == QgsWkbTypes.GeometryCollection:
                    temp_list = diff_geom.asGeometryCollection()
                    for i in temp_list:
                        if i.type() == geom.type():
                            diff_geom = QgsGeometry(i)
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMapA)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

            count += 1
            feedback.setProgress(int(count * total))

        length = len(sourceA.fields())
        atMapA = [None] * length

        for featA in sourceB.getFeatures(QgsFeatureRequest().setDestinationCrs(sourceA.sourceCrs())):
            if feedback.isCanceled():
                break

            add = False
            geom = featA.geometry()
            diff_geom = QgsGeometry(geom)
            atMap = [None] * length
            atMap.extend(featA.attributes())
            intersects = indexA.intersects(geom.boundingBox())

            if len(intersects) < 1:
                try:
                    outFeat.setGeometry(geom)
                    outFeat.setAttributes(atMap)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))
            else:
                request = QgsFeatureRequest().setFilterFids(intersects).setSubsetOfAttributes([])
                request.setDestinationCrs(sourceA.sourceCrs())

                # use prepared geometries for faster intersection tests
                engine = QgsGeometry.createGeometryEngine(diff_geom.geometry())
                engine.prepareGeometry()

                for featB in sourceA.getFeatures(request):
                    atMapB = featB.attributes()
                    tmpGeom = featB.geometry()

                    if engine.intersects(tmpGeom.geometry()):
                        add = True
                        diff_geom = QgsGeometry(diff_geom.difference(tmpGeom))
                    else:
                        try:
                            # Ihis only happens if the bounding box
                            # intersects, but the geometry doesn't
                            outFeat.setGeometry(diff_geom)
                            outFeat.setAttributes(atMap)
                            sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                        except:
                            feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

            if add:
                try:
                    outFeat.setGeometry(diff_geom)
                    outFeat.setAttributes(atMap)
                    sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                except:
                    feedback.pushInfo(self.tr('Feature geometry error: One or more output features ignored due to invalid geometry.'))

            count += 1
            feedback.setProgress(int(count * total))

        return {self.OUTPUT: dest_id}
Example #32
0
def clip(layer_to_clip, mask_layer, callback=None):
    """Clip a vector layer with another.

    Issue https://github.com/inasafe/inasafe/issues/3186

    Note : This algorithm is copied from :
    https://github.com/qgis/QGIS/blob/master/python/plugins/processing/algs/
    qgis/Clip.py

    :param layer_to_clip: The vector layer to clip.
    :type layer_to_clip: QgsVectorLayer

    :param mask_layer: The vector layer to use for clipping.
    :type mask_layer: QgsVectorLayer

    :param callback: A function to all to indicate progress. The function
        should accept params 'current' (int), 'maximum' (int) and 'step' (str).
        Defaults to None.
    :type callback: function

    :return: The clip vector layer.
    :rtype: QgsVectorLayer

    .. versionadded:: 4.0
    """
    output_layer_name = clip_steps['output_layer_name']
    output_layer_name = output_layer_name % (
        layer_to_clip.keywords['layer_purpose'])
    processing_step = clip_steps['step_name']

    writer = create_memory_layer(output_layer_name,
                                 layer_to_clip.geometryType(),
                                 layer_to_clip.crs(), layer_to_clip.fields())
    writer.startEditing()

    # Begin copy/paste from Processing plugin.
    # Please follow their code as their code is optimized.
    # The code below is not following our coding standards because we want to
    # be able to track any diffs from QGIS easily.

    # first build up a list of clip geometries
    clip_geometries = []
    request = QgsFeatureRequest().setSubsetOfAttributes([])
    for mask_feature in mask_layer.getFeatures(request):
        clip_geometries.append(QgsGeometry(mask_feature.geometry()))

    # are we clipping against a single feature? if so,
    # we can show finer progress reports
    if len(clip_geometries) > 1:
        # noinspection PyTypeChecker,PyCallByClass,PyArgumentList
        combined_clip_geom = QgsGeometry.unaryUnion(clip_geometries)
        single_clip_feature = False
    else:
        combined_clip_geom = clip_geometries[0]
        single_clip_feature = True

    # use prepared geometries for faster intersection tests
    # noinspection PyArgumentList
    engine = QgsGeometry.createGeometryEngine(combined_clip_geom.geometry())
    engine.prepareGeometry()

    tested_feature_ids = set()

    for i, clip_geom in enumerate(clip_geometries):
        request = QgsFeatureRequest().setFilterRect(clip_geom.boundingBox())
        input_features = [f for f in layer_to_clip.getFeatures(request)]

        if not input_features:
            continue

        if single_clip_feature:
            total = 100.0 / len(input_features)
        else:
            total = 0

        for current, in_feat in enumerate(input_features):
            if not in_feat.geometry():
                continue

            if in_feat.id() in tested_feature_ids:
                # don't retest a feature we have already checked
                continue

            tested_feature_ids.add(in_feat.id())

            if not engine.intersects(in_feat.geometry().geometry()):
                continue

            if not engine.contains(in_feat.geometry().geometry()):
                cur_geom = in_feat.geometry()
                new_geom = combined_clip_geom.intersection(cur_geom)
                if new_geom.wkbType() == QgsWKBTypes.Unknown \
                        or QgsWKBTypes.flatType(
                            new_geom.geometry().wkbType()) == \
                                QgsWKBTypes.GeometryCollection:
                    int_com = in_feat.geometry().combine(new_geom)
                    int_sym = in_feat.geometry().symDifference(new_geom)
                    if not int_com or not int_sym:
                        # LOGGER.debug(
                        #     tr('GEOS geoprocessing error: One or more input '
                        #        'features have invalid geometry.'))
                        pass
                    else:
                        new_geom = int_com.difference(int_sym)
                        if new_geom.isGeosEmpty()\
                                or not new_geom.isGeosValid():
                            # LOGGER.debug(
                            #     tr('GEOS geoprocessing error: One or more '
                            #        'input features have invalid geometry.'))
                            pass
            else:
                # clip geometry totally contains feature geometry,
                # so no need to perform intersection
                new_geom = in_feat.geometry()

            try:
                out_feat = QgsFeature()
                out_feat.setGeometry(new_geom)
                out_feat.setAttributes(in_feat.attributes())
                if new_geom.type() == layer_to_clip.geometryType():
                    writer.addFeature(out_feat)
            except:
                LOGGER.debug(
                    tr('Feature geometry error: One or more output features '
                       'ignored due to invalid geometry.'))
                continue

            # TODO implement callback
            if single_clip_feature:
                # progress.setPercentage(int(current * total))
                pass

        if not single_clip_feature:
            # coarse progress report for multiple clip geometries
            # progress.setPercentage(100.0 * i / len(clip_geoms))
            pass

    # End copy/paste from Processing plugin.
    writer.commitChanges()

    writer.keywords = layer_to_clip.keywords.copy()
    writer.keywords['title'] = output_layer_name
    check_layer(writer)
    return writer