Cut a geometry along a polyline.
Use case
You might cut a polygon representing a large parcel to subdivide it into smaller parcels.
How to use the sample
Tap the "Cut" button to cut the polygon with the polyline and see the resulting parts (shaded in different colors).
How it works
- Pass the geometry and polyline to
GeometryEngine.cutto cut the geometry along the polyline. - Loop through the returned list of part geometries. Some of these geometries may be multi-part.
Relevant API
- GeometryEngine
- Polygon
- Polyline
Additional information
This sample uses the GeoView-Compose Toolkit module to be able to implement a composable MapView.
Tags
cut, geometry, geoview-compose, split, toolkit
Sample Code
/* Copyright 2025 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.
*
*/
package com.esri.arcgismaps.sample.cutgeometry.components
import android.app.Application
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.viewModelScope
import com.arcgismaps.Color
import com.arcgismaps.geometry.GeometryEngine
import com.arcgismaps.geometry.Point
import com.arcgismaps.geometry.Polygon
import com.arcgismaps.geometry.PolygonBuilder
import com.arcgismaps.geometry.Polyline
import com.arcgismaps.geometry.PolylineBuilder
import com.arcgismaps.geometry.SpatialReference
import com.arcgismaps.mapping.ArcGISMap
import com.arcgismaps.mapping.BasemapStyle
import com.arcgismaps.mapping.Viewpoint
import com.arcgismaps.mapping.symbology.SimpleFillSymbol
import com.arcgismaps.mapping.symbology.SimpleFillSymbolStyle
import com.arcgismaps.mapping.symbology.SimpleLineSymbol
import com.arcgismaps.mapping.symbology.SimpleLineSymbolStyle
import com.arcgismaps.mapping.view.Graphic
import com.arcgismaps.mapping.view.GraphicsOverlay
import com.arcgismaps.toolkit.geoviewcompose.MapViewProxy
import com.esri.arcgismaps.sample.cutgeometry.R
import com.esri.arcgismaps.sample.sampleslib.components.MessageDialogViewModel
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.asStateFlow
import kotlinx.coroutines.launch
class CutGeometryViewModel(application: Application) : AndroidViewModel(application) {
// create a map with the topographic basemap style
val arcGISMap by mutableStateOf(
ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
initialViewpoint = Viewpoint(
latitude = 39.8,
longitude = -98.6,
scale = 10e7
)
}
)
// create a MapViewProxy to interact with the MapView
val mapViewProxy = MapViewProxy()
// get a polygon corresponding to Lake Superior
private val lakeSuperiorPolygon = makeLakeSuperior()
// get a polyline that divides Lake Superior into a Canada side and US side
private val borderPolyline = makeBorderPolyline()
// create a graphic for the polygon representing Lake Superior
private val polygonGraphic = Graphic(
geometry = lakeSuperiorPolygon,
symbol = SimpleFillSymbol(
style = SimpleFillSymbolStyle.Solid,
color = Color(R.color.transparentBlue),
outline = SimpleLineSymbol(
style = SimpleLineSymbolStyle.Solid,
color = Color.blue,
width = 2F
)
)
)
// create a graphic for the cut line
private val polylineGraphic = Graphic(
geometry = borderPolyline,
symbol = SimpleLineSymbol(
style = SimpleLineSymbolStyle.Dot,
color = Color.red,
width = 3F
)
)
// create a state flow to handle the reset button
private val _isResetButtonEnabled = MutableStateFlow(false)
val isResetButtonEnabled = _isResetButtonEnabled.asStateFlow()
// create a state flow to handle the cut button
private val _isCutButtonEnabled = MutableStateFlow(false)
val isCutButtonEnabled = _isCutButtonEnabled.asStateFlow()
// create a graphic overlay
val graphicsOverlay = GraphicsOverlay()
// create a message dialog view model for handling error messages
val messageDialogVM = MessageDialogViewModel()
init {
viewModelScope.launch {
arcGISMap.load().onFailure { error ->
messageDialogVM.showMessageDialog(
title = "Failed to load map",
description = error.message.toString()
)
}.onSuccess {
graphicsOverlay.graphics.add(polygonGraphic)
graphicsOverlay.graphics.add(polylineGraphic)
polygonGraphic.geometry?.let { polygonToCut ->
mapViewProxy.setViewpoint(Viewpoint(polygonToCut))
}
_isCutButtonEnabled.value = true
}
}
}
/**
* Clear the current graphics, then re-add the graphics for Lake Superior and the cut polyline.
*/
fun resetGeometry() {
graphicsOverlay.graphics.clear()
graphicsOverlay.graphics.add(polygonGraphic)
graphicsOverlay.graphics.add(polylineGraphic)
polygonGraphic.geometry?.let { polygonToCut ->
mapViewProxy.setViewpoint(Viewpoint(polygonToCut))
}
_isResetButtonEnabled.value = false
_isCutButtonEnabled.value = true
}
/**
* Cut the Lake Superior graphic into a US side and Canada side using the cut polyline
* and then add the resulting graphics to the graphics overlay.
*/
fun cutGeometry() {
polygonGraphic.geometry?.let { graphicGeometry ->
val parts = GeometryEngine.tryCut(
geometry = graphicGeometry,
cutter = polylineGraphic.geometry as Polyline
)
// create graphics for the US and Canada sides
val canadaSide = Graphic(
geometry = parts[0],
symbol = SimpleFillSymbol(
style = SimpleFillSymbolStyle.BackwardDiagonal,
color = Color.green,
outline = SimpleLineSymbol(
style = SimpleLineSymbolStyle.Null,
color = Color.blue,
width = 0F
)
)
)
val usSide = Graphic(
geometry = parts[1],
symbol = SimpleFillSymbol(
style = SimpleFillSymbolStyle.ForwardDiagonal,
color = Color.yellow,
outline = SimpleLineSymbol(
style = SimpleLineSymbolStyle.Null,
color = Color.blue,
width = 0F
)
)
)
// add the graphics to the graphics overlay
graphicsOverlay.graphics.addAll(listOf(canadaSide, usSide))
// update button state
_isCutButtonEnabled.value = false
_isResetButtonEnabled.value = true
}
}
/**
* Define a blue color for polygon boundary.
*/
private val Color.Companion.blue: Color
get() {
return fromRgba(
r = 0,
g = 0,
b = 255,
a = 255
)
}
/**
* Create a polygon corresponding to Lake Superior.
*/
private fun makeLakeSuperior() : Polygon {
return PolygonBuilder(SpatialReference.webMercator()) {
addPoint(Point(x = -10254374.668616, y = 5908345.076380))
addPoint(Point(x = -10178382.525314, y = 5971402.386779))
addPoint(Point(x = -10118558.923141, y = 6034459.697178))
addPoint(Point(x = -9993252.729399, y = 6093474.872295))
addPoint(Point(x = -9882498.222673, y = 6209888.368416))
addPoint(Point(x = -9821057.766387, y = 6274562.532928))
addPoint(Point(x = -9690092.583250, y = 6241417.023616))
addPoint(Point(x = -9605207.742329, y = 6206654.660191))
addPoint(Point(x = -9564786.389509, y = 6108834.986367))
addPoint(Point(x = -9449989.747500, y = 6095091.726408))
addPoint(Point(x = -9462116.153346, y = 6044160.821855))
addPoint(Point(x = -9417652.665244, y = 5985145.646738))
addPoint(Point(x = -9438671.768711, y = 5946341.148031))
addPoint(Point(x = -9398250.415891, y = 5922088.336339))
addPoint(Point(x = -9419269.519357, y = 5855797.317714))
addPoint(Point(x = -9467775.142741, y = 5858222.598884))
addPoint(Point(x = -9462924.580403, y = 5902686.086985))
addPoint(Point(x = -9598740.325877, y = 5884092.264688))
addPoint(Point(x = -9643203.813979, y = 5845287.765981))
addPoint(Point(x = -9739406.633691, y = 5879241.702350))
addPoint(Point(x = -9783061.694736, y = 5922896.763395))
addPoint(Point(x = -9844502.151022, y = 5936640.023354))
addPoint(Point(x = -9773360.570059, y = 6019099.583107))
addPoint(Point(x = -9883306.649729, y = 5968977.105610))
addPoint(Point(x = -9957681.938918, y = 5912387.211662))
addPoint(Point(x = -10055501.612742, y = 5871965.858842))
addPoint(Point(x = -10116942.069028, y = 5884092.264688))
addPoint(Point(x = -10111283.079633, y = 5933406.315128))
addPoint(Point(x = -10214761.742852, y = 5888134.399970))
addPoint(Point(x = -10254374.668616, y = 5901877.659929))
}.toGeometry()
}
/**
* Create a polyline corresponding to the US/Canada border over Lake Superior.
*/
private fun makeBorderPolyline() : Polyline {
return PolylineBuilder(SpatialReference.webMercator()) {
addPoint(Point(x = -9981328.687124, y = 6111053.281447))
addPoint(Point(x = -9946518.044066, y = 6102350.620682))
addPoint(Point(x = -9872545.427566, y = 6152390.920079))
addPoint(Point(x = -9838822.617103, y = 6157830.083057))
addPoint(Point(x = -9446115.050097, y = 5927209.572793))
addPoint(Point(x = -9430885.393759, y = 5876081.440801))
addPoint(Point(x = -9415655.737420, y = 5860851.784463))
}.toGeometry()
}
}