Cut geometry

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage x:Class="ArcGIS.Samples.CutGeometry.CutGeometry"
             xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:esriUI="clr-namespace:Esri.ArcGISRuntime.Maui;assembly=Esri.ArcGISRuntime.Maui">
    <Grid>
        <esriUI:MapView x:Name="MyMapView" />
        <Button x:Name="CutButton"
                Margin="10"
                Clicked="CutButton_Clicked"
                HorizontalOptions="End"
                Text="Cut"
                VerticalOptions="Start" />
    </Grid>
</ContentPage>

// Copyright 2022 Esri.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
// You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific
// language governing permissions and limitations under the License.

using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Symbology;
using Esri.ArcGISRuntime.UI;
using Color = System.Drawing.Color;
using PointCollection = Esri.ArcGISRuntime.Geometry.PointCollection;

namespace ArcGIS.Samples.CutGeometry
{
    [ArcGIS.Samples.Shared.Attributes.Sample(
        name: "Cut geometry",
        category: "Geometry",
        description: "Cut a geometry along a polyline.",
        instructions: "Tap the \"Cut\" button to cut the polygon with the polyline and see the resulting parts (shaded in different colors).",
        tags: new[] { "cut", "geometry", "split" })]
    public partial class CutGeometry
    {
        // Graphics overlay to display the graphics.
        private GraphicsOverlay _graphicsOverlay;

        // Graphic that represents the polygon of Lake Superior.
        private Graphic _lakeSuperiorPolygonGraphic;

        // Graphic that represents the Canada and USA border (polyline) of Lake Superior.
        private Graphic _countryBorderPolylineGraphic;

        private bool _cut;

        public CutGeometry()
        {
            InitializeComponent();

            // Create a map with a topographic basemap.
            Map newMap = new Map(BasemapStyle.ArcGISTopographic);

            // Assign the map to the MapView.
            MyMapView.Map = newMap;

            // Create a graphics overlay to hold the various graphics.
            _graphicsOverlay = new GraphicsOverlay();

            // Add the created graphics overlay to the MapView.
            MyMapView.GraphicsOverlays.Add(_graphicsOverlay);

            // Create a simple line symbol for the outline of the Lake Superior graphic.
            SimpleLineSymbol lakeSuperiorSimpleLineSymbol = new SimpleLineSymbol(SimpleLineSymbolStyle.Solid, Color.Blue, 4);

            // Create the color that will be used for the fill the Lake Superior graphic. It will be a semi-transparent, blue color.
            Color lakeSuperiorFillColor = Color.FromArgb(34, 0, 0, 255);

            // Create the simple fill symbol for the Lake Superior graphic - comprised of a fill style, fill color and outline.
            SimpleFillSymbol lakeSuperiorSimpleFillSymbol = new SimpleFillSymbol(SimpleFillSymbolStyle.Solid, lakeSuperiorFillColor, lakeSuperiorSimpleLineSymbol);

            // Create the graphic for Lake Superior - comprised of a polygon shape and fill symbol.
            _lakeSuperiorPolygonGraphic = new Graphic(CreateLakeSuperiorPolygon(), lakeSuperiorSimpleFillSymbol);

            // Add the Lake Superior graphic to the graphics overlay collection.
            _graphicsOverlay.Graphics.Add(_lakeSuperiorPolygonGraphic);

            // Create a simple line symbol for the Canada and USA border (polyline) of Lake Superior.
            SimpleLineSymbol countryBorderSimpleLineSymbol = new SimpleLineSymbol(SimpleLineSymbolStyle.Dot, Color.Red, 5);

            // Create the graphic for Canada and USA border (polyline) of Lake Superior - comprised of a polyline shape and line symbol.
            _countryBorderPolylineGraphic = new Graphic(CreateBorder(), countryBorderSimpleLineSymbol);

            // Add the Canada and USA border graphic to the graphics overlay collection.
            _graphicsOverlay.Graphics.Add(_countryBorderPolylineGraphic);

            // Set the initial visual extent of the map view to that of Lake Superior.
            MyMapView.SetViewpointGeometryAsync(_lakeSuperiorPolygonGraphic.Geometry);
        }

        private void CutButton_Clicked(object sender, EventArgs e)
        {
            if (!_cut)
            {
                Cut();
                _cut = true;
            }
            else
            {
                Reset();
                _cut = false;
            }

            CutButton.Text = _cut ? "Reset" : "Cut";
        }

        private void Cut()
        {
            // Cut the polygon geometry with the polyline, expect two geometries.
            Geometry[] cutGeometries = _lakeSuperiorPolygonGraphic.Geometry.Cut((Polyline)_countryBorderPolylineGraphic.Geometry);

            // Create a simple line symbol for the outline of the Canada side of Lake Superior.
            SimpleLineSymbol canadaSideSimpleLineSymbol = new SimpleLineSymbol(SimpleLineSymbolStyle.Null, System.Drawing.Color.Blue, 0);

            // Create the simple fill symbol for the Canada side of Lake Superior graphic - comprised of a fill style, fill color and outline.
            SimpleFillSymbol canadaSideSimpleFillSymbol = new SimpleFillSymbol(SimpleFillSymbolStyle.ForwardDiagonal, System.Drawing.Color.Green, canadaSideSimpleLineSymbol);

            // Create the graphic for the Canada side of Lake Superior - comprised of a polygon shape and fill symbol.
            Graphic canadaSideGraphic = new Graphic(cutGeometries[0], canadaSideSimpleFillSymbol);

            // Add the Canada side of the Lake Superior graphic to the graphics overlay collection.
            _graphicsOverlay.Graphics.Add(canadaSideGraphic);

            // Create a simple line symbol for the outline of the USA side of Lake Superior.
            SimpleLineSymbol usaSideSimpleLineSymbol = new SimpleLineSymbol(SimpleLineSymbolStyle.Null, System.Drawing.Color.Blue, 0);

            // Create the simple fill symbol for the USA side of Lake Superior graphic - comprised of a fill style, fill color and outline.
            SimpleFillSymbol usaSideSimpleFillSymbol = new SimpleFillSymbol(SimpleFillSymbolStyle.ForwardDiagonal, System.Drawing.Color.Yellow, usaSideSimpleLineSymbol);

            // Create the graphic for the USA side of Lake Superior - comprised of a polygon shape and fill symbol.
            Graphic usaSideGraphic = new Graphic(cutGeometries[1], usaSideSimpleFillSymbol);

            // Add the USA side of the Lake Superior graphic to the graphics overlay collection.
            _graphicsOverlay.Graphics.Add(usaSideGraphic);
        }

        private void Reset()
        {
            // Reset the graphics.
            _graphicsOverlay.Graphics.Clear();
            _graphicsOverlay.Graphics.Add(_lakeSuperiorPolygonGraphic);
            _graphicsOverlay.Graphics.Add(_countryBorderPolylineGraphic);
        }

        private Polyline CreateBorder()
        {
            // Create a point collection that represents the Canada and USA border (polyline) of Lake Superior. Use the same spatial reference as the underlying base map.
            PointCollection borderCountryPointCollection = new PointCollection(SpatialReferences.WebMercator)
            {
                // Add all of the border map points to the point collection.
                new MapPoint(-9981328.687124, 6111053.281447),
                new MapPoint(-9946518.044066, 6102350.620682),
                new MapPoint(-9872545.427566, 6152390.920079),
                new MapPoint(-9838822.617103, 6157830.083057),
                new MapPoint(-9446115.050097, 5927209.572793),
                new MapPoint(-9430885.393759, 5876081.440801),
                new MapPoint(-9415655.737420, 5860851.784463)
            };

            // Create a polyline geometry from the point collection.
            Polyline borderCountryPolyline = new Polyline(borderCountryPointCollection);

            // Return the polyline.
            return borderCountryPolyline;
        }

        private Polygon CreateLakeSuperiorPolygon()
        {
            // Create a point collection that represents Lake Superior (polygon). Use the same spatial reference as the underlying base map.
            PointCollection lakeSuperiorPointCollection = new PointCollection(SpatialReferences.WebMercator)
            {
                // Add all of the lake Superior boundary map points to the point collection.
                new MapPoint(-10254374.668616, 5908345.076380),
                new MapPoint(-10178382.525314, 5971402.386779),
                new MapPoint(-10118558.923141, 6034459.697178),
                new MapPoint(-9993252.729399, 6093474.872295),
                new MapPoint(-9882498.222673, 6209888.368416),
                new MapPoint(-9821057.766387, 6274562.532928),
                new MapPoint(-9690092.583250, 6241417.023616),
                new MapPoint(-9605207.742329, 6206654.660191),
                new MapPoint(-9564786.389509, 6108834.986367),
                new MapPoint(-9449989.747500, 6095091.726408),
                new MapPoint(-9462116.153346, 6044160.821855),
                new MapPoint(-9417652.665244, 5985145.646738),
                new MapPoint(-9438671.768711, 5946341.148031),
                new MapPoint(-9398250.415891, 5922088.336339),
                new MapPoint(-9419269.519357, 5855797.317714),
                new MapPoint(-9467775.142741, 5858222.598884),
                new MapPoint(-9462924.580403, 5902686.086985),
                new MapPoint(-9598740.325877, 5884092.264688),
                new MapPoint(-9643203.813979, 5845287.765981),
                new MapPoint(-9739406.633691, 5879241.702350),
                new MapPoint(-9783061.694736, 5922896.763395),
                new MapPoint(-9844502.151022, 5936640.023354),
                new MapPoint(-9773360.570059, 6019099.583107),
                new MapPoint(-9883306.649729, 5968977.105610),
                new MapPoint(-9957681.938918, 5912387.211662),
                new MapPoint(-10055501.612742, 5871965.858842),
                new MapPoint(-10116942.069028, 5884092.264688),
                new MapPoint(-10111283.079633, 5933406.315128),
                new MapPoint(-10214761.742852, 5888134.399970),
                new MapPoint(-10254374.668616, 5901877.659929)
            };

            // Create a polyline geometry from the point collection.
            Polygon lakeSuperiorPolygon = new Polygon(lakeSuperiorPointCollection);

            // Return the polygon.
            return lakeSuperiorPolygon;
        }
    }
}