Analyze viewshed (geoprocessing)

Calculate a viewshed using a geoprocessing service, in this case showing what parts of a landscape are visible from points on mountainous terrain.

Use case

A viewshed is used to highlight what is visible from a given point. A viewshed could be created to show what a hiker might be able to see from a given point at the top of a mountain. Equally, a viewshed could also be created from a point representing the maximum height of a proposed wind turbine to see from what areas the turbine would be visible.

How to use the sample

Click the map to see all areas visible from that point within a 15km radius. Clicking on an elevated area will highlight a larger part of the surrounding landscape. It may take a few seconds for the task to run and send back the results.

How it works

1. Create a GeoprocessingTask object with the URL set to a geoprocessing service endpoint.
2. Create a FeatureCollectionTable object and add a new Feature object whose geometry is the viewshed's observer Point.
3. Make a GeoprocessingParameters object passing in the observer point.
4. Use the geoprocessing task to create a GeoprocessingJob object with the parameters.
5. Start the job and wait for it to complete and return a GeoprocessingResult object.
6. Get the resulting GeoprocessingFeatures object.
7. Iterate through the viewshed features to use their geometry or display the geometry in a new Graphic object.

Relevant API

• FeatureCollectionTable
• GeoprocessingFeatures
• GeoprocessingJob
• GeoprocessingParameters
• GeoprocessingResult
• GeoprocessingTask

Tags

geoprocessing, heat map, heatmap, viewshed

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<UserControl
    x:Class="ArcGIS.UWP.Samples.AnalyzeViewshed.AnalyzeViewshed"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:esriUI="using:Esri.ArcGISRuntime.UI.Controls"
    mc:Ignorable="d"
    d:DesignHeight="300"
    d:DesignWidth="400">

    <Grid>
        <esriUI:MapView x:Name="MyMapView" />
        <Border Style="{StaticResource BorderStyle}">
            <Grid>
                <TextBlock Text="Click map to execute viewshed analysis."
                           HorizontalAlignment="Center" VerticalAlignment="Center" />

                <Grid x:Name="busyOverlay" Margin="-20" Visibility="Collapsed" Background="#8C000000" Grid.RowSpan="4">
                    <Border HorizontalAlignment="Center" VerticalAlignment="Center" Padding="10" Background="#FFC6C4C4">
                        <Grid>
                            <ProgressBar IsIndeterminate="True" x:Name="progress" Height="20" />
                            <TextBlock Text="Executing analysis..." HorizontalAlignment="Center" Margin="5" Height="20" />
                        </Grid>
                    </Border>
                </Grid>
            </Grid>
        </Border>
    </Grid>
</UserControl>