示例#1
0
        public IPoint2D GetCentroid(bool envelope)
        {
            if (envelope)
            {
                var env = _geom.Envelope();
                var ll  = env.GetLowerLeftCoordinate();
                var ur  = env.GetUpperRightCoordinate();

                return(ObjectFactory.CreatePoint2D((ll.X + ur.X) / 2.0, (ll.Y + ur.Y) / 2.0));
            }
            else
            {
                var cnt   = _geom.GetCentroid();
                var coord = cnt.GetCoordinate();

                return(ObjectFactory.CreatePoint2D(coord.GetX(), coord.GetY()));
            }
        }
示例#2
0
        private void btnFindFeaturesInBuffer_Click(object sender, EventArgs e)
        {
            MgSelectionBase           selection      = _viewer.GetSelection();
            MgReadOnlyLayerCollection selectedLayers = selection.GetLayers();

            if (selectedLayers == null)
            {
                MessageBox.Show("Select a parcel");
                return;
            }
            MgLayerBase parcels = null;

            for (int i = 0; i < selectedLayers.GetCount(); i++)
            {
                MgLayerBase layer = selectedLayers.GetItem(i);
                if (layer.Name == "Parcels")
                {
                    parcels = layer;
                    break;
                }
            }
            if (parcels == null)
            {
                MessageBox.Show("Select a parcel");
                return;
            }

            int bufferRingSize = 500; // measured in metres

            // Set up some objects for coordinate conversion

            MgMapBase           map             = _viewer.GetMap();
            MgLayerCollection   mapLayers       = map.GetLayers();
            MgMapViewerProvider provider        = _viewer.GetProvider();
            MgResourceService   resourceService = (MgResourceService)provider.CreateService(MgServiceType.ResourceService);
            //Casting to MgdFeatureService because we want to use convenience APIs
            MgFeatureService featureService = (MgdFeatureService)provider.CreateService(MgServiceType.FeatureService);
            string           sessionId      = Guid.NewGuid().ToString();

            String                    mapWktSrs               = map.GetMapSRS();
            MgAgfReaderWriter         agfReaderWriter         = new MgAgfReaderWriter();
            MgWktReaderWriter         wktReaderWriter         = new MgWktReaderWriter();
            MgCoordinateSystemFactory coordinateSystemFactory = new MgCoordinateSystemFactory();
            MgCoordinateSystem        srs        = coordinateSystemFactory.Create(mapWktSrs);
            MgMeasure                 srsMeasure = srs.GetMeasure();

            // Check for a buffer layer. If it exists, delete
            // the current features.
            // If it does not exist, create a feature source and
            // a layer to hold the buffer.

            BufferHelper helper      = new BufferHelper();
            MgdLayer     bufferLayer = null;
            int          layerIndex  = map.GetLayers().IndexOf("Buffer");

            if (layerIndex < 0)
            {
                // The layer does not exist and must be created.

                MgResourceIdentifier bufferFeatureResId = new MgResourceIdentifier("Session:" + sessionId + "//Buffer.FeatureSource");
                helper.CreateBufferFeatureSource(featureService, mapWktSrs, bufferFeatureResId);
                bufferLayer = helper.CreateBufferLayer(resourceService, bufferFeatureResId, sessionId);
                map.GetLayers().Insert(0, bufferLayer);
            }
            else
            {
                bufferLayer = (MgdLayer)map.GetLayers().GetItem(layerIndex);
                bufferLayer.DeleteFeatures("ID like '%'");
            }

            // Check for a parcel marker layer. If it exists, delete
            // the current features.
            // If it does not exist, create a feature source and
            // a layer to hold the parcel markers.

            MgdLayer parcelMarkerLayer = null;

            layerIndex = map.GetLayers().IndexOf("ParcelMarker");
            if (layerIndex < 0)
            {
                MgResourceIdentifier parcelFeatureResId = new MgResourceIdentifier("Session:" + sessionId + "//ParcelMarker.FeatureSource");
                helper.CreateParcelMarkerFeatureSource(featureService, mapWktSrs, parcelFeatureResId);
                parcelMarkerLayer = helper.CreateParcelMarkerLayer(resourceService, parcelFeatureResId, sessionId);
                map.GetLayers().Insert(0, parcelMarkerLayer);
            }
            else
            {
                parcelMarkerLayer = (MgdLayer)map.GetLayers().GetItem(layerIndex);
                parcelMarkerLayer.DeleteFeatures("ID like '%'");
            }

            // Check each layer in the selection.

            for (int i = 0; i < selectedLayers.GetCount(); i++)
            {
                // Only check selected features in the Parcels layer.

                MgdLayer layer = (MgdLayer)selectedLayers.GetItem(i);

                if (layer.GetName() == "Parcels")
                {
                    string geomName = layer.GetFeatureGeometryName();
                    System.Diagnostics.Trace.TraceInformation("Marking all parcels inside the buffer that are of type 'MFG'");

                    MgFeatureReader featureReader = selection.GetSelectedFeatures(layer, layer.GetFeatureClassName(), false);


                    // Process each item in the MgFeatureReader. Get the
                    // geometries from all the selected features and
                    // merge them into a single geometry.

                    MgGeometryCollection inputGeometries = new MgGeometryCollection();
                    while (featureReader.ReadNext())
                    {
                        MgByteReader featureGeometryData = featureReader.GetGeometry(geomName);
                        MgGeometry   featureGeometry     = agfReaderWriter.Read(featureGeometryData);

                        inputGeometries.Add(featureGeometry);
                    }

                    MgGeometryFactory geometryFactory  = new MgGeometryFactory();
                    MgGeometry        mergedGeometries = geometryFactory.CreateMultiGeometry(inputGeometries);

                    // Create a buffer from the merged geometries

                    double     bufferDist     = srs.ConvertMetersToCoordinateSystemUnits(bufferRingSize);
                    MgGeometry bufferGeometry = mergedGeometries.Buffer(bufferDist, srsMeasure);

                    // Create a filter to select parcels within the buffer. Combine
                    // a basic filter and a spatial filter to select all parcels
                    // within the buffer that are of type "MFG".

                    MgFeatureQueryOptions queryOptions = new MgFeatureQueryOptions();
                    queryOptions.SetFilter("RTYPE = 'MFG'");
                    queryOptions.SetSpatialFilter(geomName, bufferGeometry, MgFeatureSpatialOperations.Inside);

                    featureReader = layer.SelectFeatures(queryOptions);

                    // Get the features from the feature source,
                    // determine the centroid of each selected feature, and
                    // add a point to the ParcelMarker layer to mark the
                    // centroid.
                    // Collect all the points into an MgFeatureCommandCollection,
                    // so they can all be added in one operation.

                    MgFeatureCommandCollection parcelMarkerCommands = new MgFeatureCommandCollection();
                    int inserted = 0;
                    while (featureReader.ReadNext())
                    {
                        MgByteReader byteReader = featureReader.GetGeometry(geomName);
                        MgGeometry   geometry   = agfReaderWriter.Read(byteReader);
                        MgPoint      point      = geometry.GetCentroid();

                        // Create an insert command for this parcel.
                        MgPropertyCollection properties = new MgPropertyCollection();
                        properties.Add(new MgGeometryProperty("ParcelLocation", agfReaderWriter.Write(point)));
                        //parcelMarkerCommands.Add(new MgInsertFeatures("ParcelMarkerClass", properties));
                        MgFeatureReader fr = parcelMarkerLayer.InsertFeatures(properties);
                        fr.Close();
                        inserted++;
                    }
                    featureReader.Close();

                    if (inserted == 0)
                    {
                        MessageBox.Show("No parcels within the buffer area match.");
                        return;
                    }

                    // Create a feature in the buffer feature source to show the area covered by the buffer.

                    MgPropertyCollection props = new MgPropertyCollection();
                    props.Add(new MgGeometryProperty("BufferGeometry", agfReaderWriter.Write(bufferGeometry)));
                    bufferLayer.InsertFeatures(props);

                    // Ensure that the buffer layer is visible and in the legend.

                    bufferLayer.SetVisible(true);
                    bufferLayer.ForceRefresh();
                    bufferLayer.SetDisplayInLegend(true);
                    parcelMarkerLayer.SetVisible(true);
                    parcelMarkerLayer.ForceRefresh();

                    MessageBox.Show("Done");
                    _viewer.RefreshMap();
                    IMapLegend legend = Shell.Instance.Legend;
                    if (legend != null)
                    {
                        legend.RefreshLegend();
                    }
                }
            }
        }