GeoElementViewshed

Creates a viewshed analysis object whose observer is defined using a GeoElement. Visible and obstructed areas are determined for an area defined by the location and orientation of a GeoElement, field of view angles, and the min/max distance range. These parameters define the frustum over which visibility is calculated from the observer element. The horizontal and vertical angles must be greater than zero and less than or equal to 120 degrees. Terrain and other obstacles between the observer and the minimum distance are excluded from the analysis, as are areas beyond the maximum distance.

The GeoElement that represents the observer for the viewshed analysis. The observer's location, heading, and pitch are determined by the location and orientation of this GeoElement. Supported GeoElement types are Graphic, Feature, DynamicEntity, and DynamicEntityObservation.

The offset angle applied to the heading of the GeoElement. The observer heading is determined by the GeoElement heading plus the heading offset.

The location offset in the X direction that defines the observer relative to the GeoElement. The observer location is determined by the GeoElement location plus the offset X,Y,Z values. Any rotations applied to the GeoElement will also be applied to the X,Y,Z offsets. This allows the observer to be positioned relative to the GeoElement and maintain the relative position even when the GeoElement moves and rotates.

The location offset in the Y direction that defines the observer relative to the GeoElement. The observer location is determined by the GeoElement location plus the offset X,Y,Z values. Any rotations applied to the GeoElement will also be applied to the X,Y,Z offsets. This allows the observer to be positioned relative to the GeoElement and maintain the relative position even when the GeoElement moves and rotates.

The location offset in the Z direction that defines the observer relative to the GeoElement. The observer location is determined by the GeoElement location plus the offset X,Y,Z values. Any rotations applied to the GeoElement will also be applied to the X,Y,Z offsets. This allows the observer to be positioned relative to the GeoElement and maintain the relative position even when the GeoElement moves and rotates.

The offset angle applied to the pitch of the GeoElement. The observer pitch is determined by the GeoElement pitch plus the pitch offset. The valid range of values for the observer pitch is from 0 to 180 degrees.

Whether or not the Viewshed frustum is visible. The frustum visibility can be controlled for individual Viewsheds.

The horizontal angle of the observer's field of vision. Visible and non-visible areas are determined for an area defined by an observer location, horizontal and vertical view angles, and a minimum/maximum distance range. These properties define a frustum (3D solid) inside of which visibility is calculated. The horizontal angle must be greater than zero to define a valid frustum and is constrained to a maximum of 360 degrees.

Whether or not an Analysis is visible. Visibility can be controlled for individual Analyses as well as for the AnalysisOverlay that contains them. Will return false if an error occurs.

The maximum distance from the observer at which visibility will be evaluated. Visibility is not evaluated beyond the maximum distance specified. This can be used to model factors that restrict the visible distance.

The minimum distance from the observer at which visibility will be evaluated. The minimum distance allows you to exclude obstacles close to the observer (the corner of a building, for example). Since terrain and other obstacles between the observer and the specified minimum distance are completely excluded from the analysis, this value should be relatively small.

The vertical angle of the observer's field of vision. Visible and non-visible areas are determined for an area defined by an observer location, horizontal and vertical view angles, and a minimum/maximum distance range. These properties define a frustum (3D solid) inside of which visibility is calculated. The vertical angle must be greater than zero to define a valid frustum and is constrained to a maximum of 360 degrees.