Show viewshed from point in scene

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Sample viewer app

Perform a viewshed analysis from a defined vantage point.

Image of viewshed location

Use case

A 3D viewshed analysis is a type of visual analysis you can perform on a scene. The viewshed shows what can be seen from a given location. The output is an overlay with two different colors - one representing the visible areas (green) and the other representing the obstructed areas (red). Viewshed analysis is a form of "exploratory analysis", which means the results are calculated on the current scale of the data, and the results are generated very quickly. If more "conclusive" results are required, consider using a GeoprocessingTask to perform a viewshed instead.

How to use the sample

Use the sliders to change the properties (heading, pitch, etc.), of the viewshed and see them updated in real time.

How it works

Create a LocationViewshed passing in the observer location, heading, pitch, horizontal/vertical angles, and min/max distances.
Set the property values on the viewshed instance for location, direction, range, and visibility properties.

Relevant API

AnalysisOverlay
ArcGISSceneLayer
ArcGISTiledElevationSource
LocationViewshed
Viewshed

About the data

The scene shows a buildings layer in Brest, France hosted on ArcGIS Online.

Additional information

This sample uses the GeoViewCompose Toolkit module to be able to implement a Composable SceneView.

Sample Code

MainActivity.kt

SceneViewModel.kt

MainScreen.kt

ViewshedOptionsScreen.kt

ViewshedSlider.kt

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/* Copyright 2023 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.showviewshedfrompointinscene

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.runtime.Composable
import com.arcgismaps.ApiKey
import com.arcgismaps.ArcGISEnvironment
import com.esri.arcgismaps.sample.sampleslib.theme.SampleAppTheme
import com.esri.arcgismaps.sample.showviewshedfrompointinscene.screens.MainScreen

class MainActivity : ComponentActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        // authentication with an API key or named user is
        // required to access basemaps and other location services
        ArcGISEnvironment.apiKey = ApiKey.create(BuildConfig.ACCESS_TOKEN)

        setContent {
            SampleAppTheme {
                ViewshedLocationApp()
            }
        }
    }

    @Composable
    private fun ViewshedLocationApp() {
        Surface(color = MaterialTheme.colorScheme.background) {
            MainScreen(sampleName = getString(R.string.show_viewshed_from_point_in_scene_app_name))
        }
    }
}