Interactive viewshed creation methods

An exploratory analysis viewshed can be created in a variety of ways based on your workflow.

The creation methods are as follows:

• Interactive Placement
• Interactive Orientation
• Observer From Camera
• Along a Line
• From Layer

To create a viewshed, click the Analysis tab and choose a viewshed template from the Exploratory 3D Analysis gallery in the Workflows group. This opens the Exploratory Analysis pane and activates the viewshed tool.

Each method generates one or more viewsheds using the creation parameters displayed in the Exploratory Analysis pane. Changes to the default parameters only affect subsequently created viewsheds.

A selected viewshed can be edited anytime using the anchors that appear on the selection, or using the Properties tab in the Exploratory Analysis pane. Additionally, you can add a configuration of the viewshed to the template gallery.

Note:

Each scene has a display budget for the number of interactive analysis objects it can contain at one time. A warning message appears when you have exceeded that limit. You must remove one or more analysis objects, or click Clear All in the Exploratory 3D Analysis gallery on the Analysis tab, before you can create more.

Interactive Placement

Place one or more viewsheds in the scene by interactively clicking to specify the placement. The viewshed is generated according to the specifications outlined in the Exploratory Analysis pane. This creation method is well suited for general exploratory investigation of visibility within a scene.

1. Click the Interactive Placement button in the Exploratory Analysis pane. Optionally, activate the pane by choosing a Viewshed tool from the template gallery on the Analysis tab.
2. Review and optionally update the creation parameters on the Create tab.
3. Click in the scene to place the viewshed observer.

   Note:

   Interactive Placement is compatible with snapping. Enable snapping in the scene view for more precise placement. For example, vertex or edge snapping allows you to snap to the edge or corner of a building.

   The observer and analysis graphics are added to the scene.

The Interactive Placement creation tool remains active to continue adding more viewsheds. Click the observer to select and edit a viewshed.

Interactive Orientation

Place one or more viewsheds within the scene by clicking both the observer (origin) location and its view direction. This creation method is well suited for interactively orienting a viewshed toward a feature or point of interest.

1. Click the Interactive Orientation button in the Exploratory Analysis pane. Optionally, activate the pane by choosing a Viewshed tool from the template gallery on the Analysis tab.
2. Review and optionally update the creation parameters.
3. Click in the scene to place the viewshed observer.

   Note:

   Interactive Orientation is compatible with snapping. Enable snapping in the scene view for more precise placement. For example, vertex or edge snapping allows you to snap to the edge or corner of a building.

4. Click again to define the camera orientation.

   The observer and analysis graphics are added to the scene.

The Interactive Orientation creation tool remains active to continue adding more viewsheds. Select a viewshed for editing by hovering over the observer and clicking it.

Observer From Camera

Place one or more viewsheds in the scene by clicking the Apply button to use the view's current camera position. This method is well suited for storing viewshed results from important viewpoints, such as bookmarks, and zooming out to identify what regions cannot be seen.

1. Click the Observer From Camera button in the Exploratory Analysis pane. Optionally, activate the pane by choosing a Viewshed tool from the template gallery on the Analysis tab.
2. Review the creation parameters and update as needed.
3. Orient the camera by repositioning the scene view as needed. Press the C key as a shortcut to activate the Explore tool or use the Navigator control in the lower left of the scene.
4. Click Apply to create the viewshed from the current camera position.

   The observer and analysis graphics are added to the scene.

The Observer From Camera creation tool remains active to continue adding more viewsheds. Click the observer to select and edit a viewshed.

Along a Line

Place one or more viewsheds along a selected feature either using percentages along the line or at specific intervals. This method is well suited for determining visibility along a route.

1. Click the Along a Line button in the Exploratory Analysis pane. Optionally, activate the pane by choosing a Viewshed tool from the template gallery on the Analysis tab.
2. Review the creation parameters and update as needed.
3. Select a methodology, either Number of Viewsheds or Segment Length, and enter the interval value.
4. Select a Facing Direction for the viewshed. You can choose from the following:
   • Forward
   • Backward
   • Left
   • Right
   • Toward a feature—Select a feature of interest to face.
   • Click—Define the point of interest interactively.
5. Select the Line Layer containing the feature you want to analyze.

   Note:

   If a single feature is not already selected, you will be prompted to make a selection.

6. Click Apply.

   The observer and analysis graphics are added to the scene.

The Along a Line creation tool remains active to continue adding more viewsheds. Select a viewshed for editing by hovering over the observer and clicking it.

From Layer

Interactive viewsheds can be generated from point layers where feature attributes set view distance, field-of-view angles, and direction parameters. This method is well suited for saving and reloading designs. Viewsheds can be saved as a stand-alone point layer and reimported so you can pick up where you left off.

1. Click the From Layer button in the Exploratory Analysis pane. Optionally, activate the pane by choosing a Viewshed tool from the template gallery on the Analysis tab.
2. Choose the layer containing the point features against which you want to perform the viewshed analysis. The menu lists all point layers present in the current map view.

   Tip:

   The scene has a display budget for the number of viewsheds it can contain at one time. A warning message appears when you have exceeded that limit, and no more viewsheds will be created.

3. Optionally, connect tool parameters to attribute fields within the point layer.

   If this is a previously saved viewshed, these are automatically connected for you. Expressions are supported.

4. Click Apply.

   The observer and analysis graphics are added to the scene according to the values defined in the attributes of the point layer. If no values are present, the default creation parameters are used.

The From Layer creation tool remains active to continue adding more viewsheds. Select a viewshed for editing by hovering over the observer and clicking it.