Python QgsVectorLayer.extent方法代码示例

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def testReadExtentOnTable(self):
        # vector layer based on a standard table
        vl0 = QgsVectorLayer(self.dbconn + ' sslmode=disable key=\'pk\' srid=4326 type=POLYGON table="qgis_test"."some_poly_data" (geom) sql=', 'test', 'postgres')
        self.assertTrue(vl0.isValid())
        self.assertTrue(vl0.dataProvider().hasMetadata())

        # set a custom extent
        originalExtent = vl0.extent()

        customExtent = QgsRectangle(-80, 80, -70, 90)
        vl0.setExtent(customExtent)

        # write xml
        doc = QDomDocument("testdoc")
        elem = doc.createElement("maplayer")
        self.assertTrue(vl0.writeLayerXml(elem, doc, QgsReadWriteContext()))

        # read xml with the custom extent. It should not be used by default
        vl1 = QgsVectorLayer()
        vl1.readLayerXml(elem, QgsReadWriteContext())
        self.assertTrue(vl1.isValid())

        self.assertEqual(vl1.extent(), originalExtent)

        # read xml with custom extent with readExtent option. Extent read from
        # xml document should NOT be used because we don't have a view or a
        # materialized view
        vl2 = QgsVectorLayer()
        vl2.setReadExtentFromXml(True)
        vl2.readLayerXml(elem, QgsReadWriteContext())
        self.assertTrue(vl2.isValid())

        self.assertEqual(vl2.extent(), originalExtent)

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
def render_layers(layer_paths):
    """

    :param layer_paths: A list of layer paths.
    :return: Buffer containing output. Note caller is responsible for closing
        the buffer with buffer.close()
    :rtype: QBuffer
    """
    layers = []
    extent = None


    crs = QgsCoordinateReferenceSystem()
    crs.createFromSrid(3857)

    for layer_path in layer_paths:
        map_layer = QgsVectorLayer(layer_path, None, 'ogr')
        QgsMapLayerRegistry.instance().addMapLayer(map_layer)
        transform = QgsCoordinateTransform(map_layer.crs(), crs)
        print map_layer.extent().toString()
        layer_extent = transform.transform(map_layer.extent())
        if extent is None:
            extent = layer_extent
        else:
            extent.combineExtentWith(layer_extent)
        print extent.toString()
        # set layer set
        layers.append(map_layer.id())  # add ID of every layer

    map_settings = QgsMapSettings()

    map_settings.setDestinationCrs(crs)
    map_settings.setCrsTransformEnabled(True)
    map_settings.setExtent(extent)
    map_settings.setOutputSize(QSize(1000, 1000))

    map_settings.setLayers(layers)

    # job = QgsMapRendererParallelJob(settings)
    job = QgsMapRendererSequentialJob(map_settings)
    job.start()
    job.waitForFinished()
    image = job.renderedImage()
    # Save teh image to a buffer
    map_buffer = QBuffer()
    map_buffer.open(QIODevice.ReadWrite)
    image.save(map_buffer, "PNG")
    image.save('/tmp/test.png', 'png')

    # clean up
    QgsMapLayerRegistry.instance().removeAllMapLayers()

    return map_buffer

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def loadLayerTable(self, carhabLayer, tableName):

        # Retrieve layer from provider.
        uri = QgsDataSourceURI()
        uri.setDatabase(carhabLayer.dbPath)

        schema = ''
        geom_column = 'the_geom'
        uri.setDataSource(schema, tableName, geom_column)

        display_name = carhabLayer.getName()+'_'+tableName

        layer = QgsVectorLayer(uri.uri(), display_name, 'spatialite')
        crsType = QgsCoordinateReferenceSystem.EpsgCrsId
        crsVal = 2154
        crs = QgsCoordinateReferenceSystem(crsVal, crsType)
        layer.setCrs(crs)

        # "Bind" layer to carhab layer.
        if self.getCarhabLayerByDbPath(carhabLayer.dbPath):
            layer.setCustomProperty('carhabLayer', carhabLayer.id)

        # Add layer to map (False to add to group)
        QgsMapLayerRegistry.instance().addMapLayer(layer, False)

        iface.mapCanvas().setExtent(layer.extent())

        return layer

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def test_run(self):
        function = FloodPolygonBuildingFunction.instance()

        hazard_path = test_data_path('hazard', 'flood_multipart_polygons.shp')
        exposure_path = test_data_path('exposure', 'buildings.shp')
        # noinspection PyCallingNonCallable
        hazard_layer = QgsVectorLayer(hazard_path, 'Flood', 'ogr')
        # noinspection PyCallingNonCallable
        exposure_layer = QgsVectorLayer(exposure_path, 'Buildings', 'ogr')

        # Let's set the extent to the hazard extent
        extent = hazard_layer.extent()
        rect_extent = [
            extent.xMinimum(), extent.yMaximum(),
            extent.xMaximum(), extent.yMinimum()]

        function.hazard = QgisWrapper(hazard_layer)
        function.exposure = QgisWrapper(exposure_layer)
        function.requested_extent = rect_extent
        function.parameters['building_type_field'] = 'TYPE'
        function.parameters['affected_field'] = 'FLOODPRONE'
        function.parameters['affected_value'] = 'YES'
        function.run()
        impact = function.impact

        # Count of flooded objects is calculated "by the hands"
        # total flooded = 27, total buildings = 129
        count = sum(impact.get_data(attribute='INUNDATED'))
        self.assertEquals(count, 33)
        count = len(impact.get_data())
        self.assertEquals(count, 176)

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def testApproxFeatureCountAndExtent(self):
        """ Test perf improvement for for https://issues.qgis.org/issues/18402 """

        tmpfile = os.path.join(self.basetestpath, 'testApproxFeatureCountAndExtent.gpkg')
        ds = ogr.GetDriverByName('GPKG').CreateDataSource(tmpfile)
        lyr = ds.CreateLayer('test', geom_type=ogr.wkbPoint)
        f = ogr.Feature(lyr.GetLayerDefn())
        f.SetGeometry(ogr.CreateGeometryFromWkt('POINT(0 1)'))
        lyr.CreateFeature(f)
        f = ogr.Feature(lyr.GetLayerDefn())
        f.SetGeometry(ogr.CreateGeometryFromWkt('POINT(2 3)'))
        lyr.CreateFeature(f)
        fid = f.GetFID()
        f = ogr.Feature(lyr.GetLayerDefn())
        f.SetGeometry(ogr.CreateGeometryFromWkt('POINT(4 5)'))
        lyr.CreateFeature(f)
        lyr.DeleteFeature(fid)
        ds = None
        ds = ogr.Open(tmpfile, update=1)
        ds.ExecuteSQL('DROP TABLE gpkg_ogr_contents')
        ds = None

        os.environ['QGIS_GPKG_FC_THRESHOLD'] = '1'
        vl = QgsVectorLayer(u'{}'.format(tmpfile) + "|layername=" + "test", 'test', u'ogr')
        self.assertTrue(vl.isValid())
        fc = vl.featureCount()
        del os.environ['QGIS_GPKG_FC_THRESHOLD']
        self.assertEqual(fc, 3) # didn't notice the hole

        reference = QgsGeometry.fromRect(QgsRectangle(0, 1, 4, 5))
        provider_extent = QgsGeometry.fromRect(vl.extent())
        self.assertTrue(QgsGeometry.compare(provider_extent.asPolygon()[0], reference.asPolygon()[0], 0.00001),
                        provider_extent.asPolygon()[0])

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def test_run(self):
        function = FloodPolygonBuildingFunction.instance()

        hazard_path = test_data_path('hazard', 'flood_multipart_polygons.shp')
        # exposure_path = test_data_path('exposure', 'buildings.shp')
        # noinspection PyCallingNonCallable
        hazard_layer = QgsVectorLayer(hazard_path, 'Flood', 'ogr')
        # noinspection PyCallingNonCallable
        # exposure_layer = QgsVectorLayer(exposure_path, 'Buildings', 'ogr')

        exposure_layer = clone_shp_layer(
            name='buildings',
            include_keywords=True,
            source_directory=test_data_path('exposure'))
        # Let's set the extent to the hazard extent
        extent = hazard_layer.extent()
        rect_extent = [
            extent.xMinimum(), extent.yMaximum(),
            extent.xMaximum(), extent.yMinimum()]

        function.hazard = SafeLayer(hazard_layer)
        function.exposure = SafeLayer(exposure_layer)
        function.requested_extent = rect_extent
        function.run()
        impact = function.impact

        # Count of flooded objects is calculated "by the hands"
        # total flooded = 27, total buildings = 129
        count = sum(impact.get_data(attribute=function.target_field))
        self.assertEquals(count, 33)
        count = len(impact.get_data())
        self.assertEquals(count, 176)

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def runTestForLayer(self, layer, testname):
        tempdir = tempfile.mkdtemp()

        layer = QgsVectorLayer(layer, 'Layer', 'ogr')
        QgsProject.instance().addMapLayer(layer)
        self.iface.mapCanvas().setExtent(layer.extent())

        geom = next(layer.getFeatures()).geometry()

        highlight = QgsHighlight(self.iface.mapCanvas(), geom, layer)
        color = QColor(Qt.red)
        highlight.setColor(color)
        highlight.setWidth(2)
        color.setAlpha(50)
        highlight.setFillColor(color)
        highlight.show()

        image = QImage(QSize(400, 400), QImage.Format_ARGB32)
        image.fill(Qt.white)
        painter = QPainter()
        painter.begin(image)
        self.iface.mapCanvas().render(painter)
        painter.end()
        control_image = os.path.join(tempdir, 'highlight_{}.png'.format(testname))
        image.save(control_image)
        checker = QgsRenderChecker()
        checker.setControlPathPrefix("highlight")
        checker.setControlName("expected_highlight_{}".format(testname))
        checker.setRenderedImage(control_image)
        self.assertTrue(checker.compareImages("highlight_{}".format(testname)))
        shutil.rmtree(tempdir)

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def test_run(self):
        function = FloodPolygonRoadsFunction.instance()

        hazard_path = test_data_path('hazard', 'flood_multipart_polygons.shp')
        exposure_path = test_data_path('exposure', 'roads.shp')
        # noinspection PyCallingNonCallable
        hazard_layer = QgsVectorLayer(hazard_path, 'Flood', 'ogr')
        # noinspection PyCallingNonCallable
        exposure_layer = QgsVectorLayer(exposure_path, 'Roads', 'ogr')

        # Let's set the extent to the hazard extent
        extent = hazard_layer.extent()
        rect_extent = [
            extent.xMinimum(), extent.yMaximum(),
            extent.xMaximum(), extent.yMinimum()]
        function.hazard = SafeLayer(hazard_layer)
        function.exposure = SafeLayer(exposure_layer)
        function.requested_extent = rect_extent
        function.run()
        impact = function.impact

        # Count of flooded objects is calculated "by the hands"
        # the count = 69
        expected_feature_total = 69
        count = sum(impact.get_data(attribute=function.target_field))
        message = 'Expecting %s, but it returns %s' % (
            expected_feature_total, count)
        self.assertEquals(count, expected_feature_total, message)

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
 def aoiExtent(cls):
     """Area of interest extent, which matches output aspect ratio"""
     uri = QgsDataSourceUri()
     uri.setDatabase(cls._PalFeaturesDb)
     uri.setDataSource('', 'aoi', 'geometry')
     aoilayer = QgsVectorLayer(uri.uri(), 'aoi', 'spatialite')
     return aoilayer.extent()

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def create_layer(self, data):
        display_name = 'some-layer'
        uri = 'Point?crs=epsg:4326&index=yes&uuid=%s' % uuid.uuid4()
        vlayer = QgsVectorLayer(uri, display_name, 'memory')
        QgsMapLayerRegistry.instance().addMapLayer(vlayer)

        provider = vlayer.dataProvider()
        vlayer.startEditing()
        provider.addAttributes([
            QgsField('population_density', QtCore.QVariant.Double),
        ])
        features = []
        for x, y, density in data:
            feat = QgsFeature()
            geom = QgsGeometry.fromPoint(QgsPoint(x, y))
            feat.setGeometry(geom)
            feat.setAttributes([density])
            features.append(feat)
        provider.addFeatures(features)
        vlayer.commitChanges()

        vlayer.updateExtents()
        self.canvas.setExtent(vlayer.extent())
        cl = QgsMapCanvasLayer(vlayer)
        self.canvas.setLayerSet([cl])
        vlayer.triggerRepaint()

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def testGeopackageExtentUpdate(self):
        """ test http://hub.qgis.org/issues/15273 """
        tmpfile = os.path.join(self.basetestpath, "testGeopackageExtentUpdate.gpkg")
        ds = ogr.GetDriverByName("GPKG").CreateDataSource(tmpfile)
        lyr = ds.CreateLayer("test", geom_type=ogr.wkbPoint)
        f = ogr.Feature(lyr.GetLayerDefn())
        f.SetGeometry(ogr.CreateGeometryFromWkt("POINT(0 0)"))
        lyr.CreateFeature(f)
        f = ogr.Feature(lyr.GetLayerDefn())
        f.SetGeometry(ogr.CreateGeometryFromWkt("POINT(1 1)"))
        lyr.CreateFeature(f)
        f = None
        f = ogr.Feature(lyr.GetLayerDefn())
        f.SetGeometry(ogr.CreateGeometryFromWkt("POINT(1 0.5)"))
        lyr.CreateFeature(f)
        f = None
        gdal.ErrorReset()
        ds.ExecuteSQL("RECOMPUTE EXTENT ON test")
        has_error = gdal.GetLastErrorMsg() != ""
        ds = None
        if has_error:
            print("Too old GDAL trunk version. Please update")
            return

        vl = QgsVectorLayer(u"{}".format(tmpfile), u"test", u"ogr")

        # Test moving a geometry that touches the bbox
        self.assertTrue(vl.startEditing())
        self.assertTrue(vl.changeGeometry(1, QgsGeometry.fromWkt("Point (0.5 0)")))
        self.assertTrue(vl.commitChanges())
        reference = QgsGeometry.fromRect(QgsRectangle(0.5, 0.0, 1.0, 1.0))
        provider_extent = QgsGeometry.fromRect(vl.extent())
        self.assertTrue(
            QgsGeometry.compare(provider_extent.asPolygon()[0], reference.asPolygon()[0], 0.00001),
            provider_extent.asPolygon()[0],
        )

        # Test deleting a geometry that touches the bbox
        self.assertTrue(vl.startEditing())
        self.assertTrue(vl.deleteFeature(2))
        self.assertTrue(vl.commitChanges())
        reference = QgsGeometry.fromRect(QgsRectangle(0.5, 0.0, 1.0, 0.5))
        provider_extent = QgsGeometry.fromRect(vl.extent())
        self.assertTrue(
            QgsGeometry.compare(provider_extent.asPolygon()[0], reference.asPolygon()[0], 0.00001),
            provider_extent.asPolygon()[0],
        )

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
def add_resource_as_geojson(resource, return_extent=False):
    if not isinstance(resource, NGWVectorLayer):
        raise NGWError('Resource type is not VectorLayer!')

    qgs_geojson_layer = QgsVectorLayer(resource.get_geojson_url(), resource.common.display_name, 'ogr')

    if not qgs_geojson_layer.isValid():
        raise NGWError('Layer %s can\'t be added to the map!' % resource.alias)

    qgs_geojson_layer.dataProvider().setEncoding('UTF-8')

    QgsMapLayerRegistry.instance().addMapLayer(qgs_geojson_layer)

    if return_extent:
        if qgs_geojson_layer.extent().isEmpty() and qgs_geojson_layer.type() == QgsMapLayer.VectorLayer:
            qgs_geojson_layer.updateExtents()
            return qgs_geojson_layer.extent()

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def test_split_by_polygon(self):
        """Test split_by_polygon work"""
        line_before = QgsVectorLayer(
            self.line_before + '.shp', 'test', 'ogr')
        expected_lines = QgsVectorLayer(
            self.line_after + '.shp', 'test', 'ogr')
        polygon_layer = QgsVectorLayer(
            self.polygon_base + '.shp', 'test', 'ogr')

        # Only one polygon is stored in the layer
        for feature in polygon_layer.getFeatures():
            polygon = feature.geometry()

        split_lines = split_by_polygon(
            line_before,
            polygon,
            mark_value=('flooded', 1))

        # Test the lines is not multipart
        for feature in split_lines.getFeatures():
            self.assertFalse(feature.geometry().isMultipart())

        self.assertEqual(expected_lines.featureCount(),
                         split_lines.featureCount())
        # Assert for every line from split_lines
        # we can find the same line
        for feature in split_lines.getFeatures():
            found = False
            for expected in expected_lines.getFeatures():
                if (feature.attributes() == expected.attributes()) and \
                   (feature.geometry().isGeosEqual(expected.geometry())):
                    found = True
                    break
            self.assertTrue(found)

        # Split by the extent (The result is the copy of the layer)
        line_before.updateExtents()
        # Expand extent to cover the lines (add epsilon to bounds)
        epsilon = 0.0001    # A small number
        extent = line_before.extent()
        new_extent = QgsRectangle(
            extent.xMinimum() - epsilon,
            extent.yMinimum() - epsilon,
            extent.xMaximum() + epsilon,
            extent.yMaximum() + epsilon
        )
        new_extent = QgsGeometry().fromRect(new_extent)
        split_lines = split_by_polygon(
            line_before,
            new_extent)
        for feature in split_lines.getFeatures():
            found = False
            for expected in line_before.getFeatures():
                if (feature.attributes() == expected.attributes()) and \
                   (feature.geometry().isGeosEqual(expected.geometry())):
                    found = True
                    break
            self.assertTrue(found)

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
    def testInitialSizeSymbolMapUnits(self):
        """Test initial size of legend with a symbol size in map units"""

        point_path = os.path.join(TEST_DATA_DIR, 'points.shp')
        point_layer = QgsVectorLayer(point_path, 'points', 'ogr')
        QgsProject.instance().addMapLayers([point_layer])

        marker_symbol = QgsMarkerSymbol.createSimple({'color': '#ff0000', 'outline_style': 'no', 'size': '5', 'size_unit': 'MapUnit'})

        point_layer.setRenderer(QgsSingleSymbolRenderer(marker_symbol))

        s = QgsMapSettings()
        s.setLayers([point_layer])
        layout = QgsLayout(QgsProject.instance())
        layout.initializeDefaults()

        map = QgsLayoutItemMap(layout)
        map.attemptSetSceneRect(QRectF(20, 20, 80, 80))
        map.setFrameEnabled(True)
        map.setLayers([point_layer])
        layout.addLayoutItem(map)
        map.setExtent(point_layer.extent())

        legend = QgsLayoutItemLegend(layout)
        legend.setTitle("Legend")
        legend.attemptSetSceneRect(QRectF(120, 20, 80, 80))
        legend.setFrameEnabled(True)
        legend.setFrameStrokeWidth(QgsLayoutMeasurement(2))
        legend.setBackgroundColor(QColor(200, 200, 200))
        legend.setTitle('')
        layout.addLayoutItem(legend)
        legend.setLinkedMap(map)

        checker = QgsLayoutChecker(
            'composer_legend_mapunits', layout)
        checker.setControlPathPrefix("composer_legend")
        result, message = checker.testLayout()
        self.assertTrue(result, message)

        # resize with non-top-left reference point
        legend.setResizeToContents(False)
        legend.setReferencePoint(QgsLayoutItem.LowerRight)
        legend.attemptMove(QgsLayoutPoint(120, 90))
        legend.attemptResize(QgsLayoutSize(50, 60))

        self.assertEqual(legend.positionWithUnits().x(), 120.0)
        self.assertEqual(legend.positionWithUnits().y(), 90.0)
        self.assertAlmostEqual(legend.pos().x(), 70, -1)
        self.assertAlmostEqual(legend.pos().y(), 30, -1)

        legend.setResizeToContents(True)
        legend.updateLegend()
        self.assertEqual(legend.positionWithUnits().x(), 120.0)
        self.assertEqual(legend.positionWithUnits().y(), 90.0)
        self.assertAlmostEqual(legend.pos().x(), 91, -1)
        self.assertAlmostEqual(legend.pos().y(), 71, -1)

        QgsProject.instance().removeMapLayers([point_layer.id()])

# 需要导入模块: from qgis.core import QgsVectorLayer [as 别名]
# 或者: from qgis.core.QgsVectorLayer import extent [as 别名]
 def loadLayer(self, path, name):
     layer = QgsVectorLayer(path, name, "ogr")
     if not layer.isValid():
         raise IOError, "Failed to open the layer"
     self.canvas.setExtent(layer.extent())
     QgsMapLayerRegistry.instance().addMapLayer(layer)
     layers = self.canvas.mapRenderer().layerSet()
     layers.append(layer.id())
     self.canvas.mapRenderer().setLayerSet(layers)