Create radial line of sight

Available with 3D Analyst license.

The Radial Line Of Sight tool shows terrain visibility from a location using given observer information. Using a surface and one or more observer locations, the tool shows areas that are visible to one or more of the observers or not visible to any.

Open Radial Line of Sight

To open the Radial Line of Sight tool, complete the following steps:

1. On the ribbon, click the Analysis tab.
2. In the Workflows group, click Visibility Analysis .
3. In the Visibility Analysis pane, click the Radial Line Of Sight tab .

Add surface information

The Radial Line Of Sight tool requires surface information to perform calculations.

1. Click the Input Surface drop-down list and select an elevation surface from the table of contents.

   Note:

   The input surface data must be in a projected coordinate system.

   Caution:

   The use of a global or large area extent image service results in excessive processing time. It is recommended that you use a local dataset or a small area extent image service.

Input observer points

You can create radial line of sight information by specifying one or more observer locations.

Input points manually

You can create radial line of sight information by manually entering known coordinates or selecting them from the map.

1. Select Enter Manually from the Observer Points drop-down list.
2. In the Observer Points text box, enter a coordinate and press Enter to add it to the list. To add points to the list, click Observer Map Point Tool and click the map.

   Observer points are marked with blue circles.

Input points from a list

You can create radial line of sight information by copying and pasting a list of coordinates or importing a .csv file.

Input points by copying and pasting

Use copy and paste functionality to add points to the Radial Line Of Sight tool.

1. Copy a list of observer points in which each point is listed on a separate line.
2. Select Enter Manually from the Observer Points drop-down list.
3. Right-click in the Observer Points list and click Paste.

   Observer points are marked with blue circles.

Input points by importing from a .csv file

Import a .csv file to add points to the Radial Line Of Sight tool.

1. Select Enter Manually from the Observer Points drop-down list.
2. Right-click in the Observer Points list and click Import.
3. Browse to the .csv file that stores the observer points, and click Open.
4. On the Select Fields dialog box, specify which fields in the .csv file store the coordinates.
5. Click OK.

   Observer points are marked with blue circles.

Input points from a feature class

You can generate radial line of sight information by selecting a feature class from the table of contents. Select the observer locations layer from the Observer Points drop-down list.

Symbology options

You can change the way the Radial Line Of Sight tool outputs are symbolized. Check the Symbolize Non-Visible Data in Output check box to symbolize nonvisible areas in red; otherwise the output only shows areas that are visible.

Enter observer information.

You can specify the observer information.

1. Expand Observer Options.
2. Change the observer information or accept the defaults.
   1. For Height Above Surface, enter values in the Observer and Surface text boxes. Click the drop-down list to select the unit of measure for observer height and surface height.
   2. For Distance, enter values in the text boxes for the minimum and maximum linear distances. Click the drop-down list to select the unit of measure for distance.
   3. For Field of View, enter values in the Horizontal and Vertical text boxes. Click the drop-down list to select the angular units for field of view.
3. Click OK to calculate visibility around the observers.

   Areas visible to an observer are shown in green. If an area is visible to more than one observer, it is shown with a unique value indicating the number of observers that can see it.

Note:

You can refine your analysis by changing the observer offset heights or fields of view.

Click Cancel to remove the observer coordinates from the tool.