Exploratory analysis in 3D is a way of performing various forms of quick investigation by interactively creating graphics and editing analysis parameters on-the-fly. The interactive tools create analytical objects by clicking in the scene or using input source layers. You can manipulate analysis parameters and receive real-time visual feedback in the scene.
There are three exploratory tools:
- Line of sight, which creates sight lines to determine if one or more targets are visible from a given observer location.
- View dome, which determines the parts of a sphere that are visible from an observer located at the center.
- Viewshed, which determines the visible surface area from a given observer location through a defined viewing angle.
Each tool uses a different method to achieve visibility analysis and has customizable creation methods and parameter values. The analysis feedback in the view is color-coded to distinguish what is obstructed, unobstructed, and out of range.
The analysis determines the visible sight lines, field of view, or spherical visibility coverage. The results are temporary and must be saved as point feature classes if you want to reload the interactive objects again.
The 3D exploratory analysis tools operate on the terrain and data layers in a scene view. The accuracy of their calculations is based on the 3D objects in the scene and their level of detail. The level of detail can vary based on the scene's camera position and graphics hardware specifications.
For 2D analysis, or for high precision needs, the analogous geoprocessing tools are recommended for the task, such as:
Specific solutions also exist to answer visibility questions by using files created with ArcGIS Solutions for Visibility Assessment.
Access the 3D exploratory tools
On the Analysis tab, in the 3D Exploratory Analysis group, click Interactive Analysis to access the tools. Any customized template you save is added to the gallery list.
Once you select a tool, the Exploratory Analysis pane appears to review and set creation properties. The tool is immediately active to begin adding analysis objects in the view. Any selected analysis object can be updated in the view using interactive handles or using the Properties tab on the Exploratory Analysis pane.
Creation methods and tips
One of the main differentiations for the interactive 3D exploratory tools over other visibility tools is that you click in the view to create graphics and manually make updates on-the-fly. Each tool offers many creation methods specific to the tool. These options include:
- Use clicks to place observers and targets.
- Choose to orient placement interactively instead of using defined values.
- Use the current camera location as the observer and only click to add targets.
- Provide line layers to use for creating targets at set intervals.
- Use a layer file to generate the analysis from. These can be converted exploratory analysis points from a previous pass.
Keyboard shortcuts can be used with your exploratory analysis workflow to navigate the viewing perspective and update observer and or target positions.
You can use snapping to help you place analysis objects in the view, like on the corner of a building for example.
Update and manage analysis objects
Selection is an important part of updating an analysis object. You can use the Exploratory Analysis pane's Property tab to browse through analysis objects and select one or all. Alternatively use the edit handles that appear over a selected object and drag to reposition or resize.
Since all analysis results are temporary, you can save templatesto keep a tool with the current settings. Or, if you work with a design regularly, you can convert your observer points or sight lines to feature classes to reuse or share with others.
The interactive exploratory tools consume part of your computer's display capabilities when they render in the 3D view. In order to not overwhelm the scene's ability to draw, there is a limit to the number and complexity of concurrent analysis objects that you can create. When this limit is reached, a notification appears in the top corner of the application. You must clear one or more existing analysis objects before you can add more. Click Clear All on the Analysis tab to clear all analysis objects.
There are many scenarios for analyzing visibility in 3D space. For example, you may be interested in where security camera coverage is lacking or duplicated. Perhaps you want to know the outward impact of an incident from a central source location. Follow the common workflows to get started using these tools and discover your own use cases.