Class Name: Conformal Behavior

Superclass - SEDRIS Abstract Base

Definition

The Geometry Hierarchy to which a Conformal Behavior is attached conforms to the terrain skin automatically, either "parallel to gravity" (e.g., ensuring that the base of a building touches the ground without warping the walls) or orthogonally to the terrain skin (e.g. a fence).

Primary Page in DRM Diagram:

• 3

Secondary Pages in DRM Diagram:

• 5
• 18

Example

1. A Model instanced to terrain. A Geometry Model Instance may specify that the location component of its Transformation is Conformal Behavior to the terrain skin. The terrain skin may use a Classification Related Geometry aggregation to separate the surface that Model conforms to from the rest of the Geometry. If so, the Conformal Behavior object can associate with the terrain skin. This would help the consumer resolve ambiguities when deriving the actual 3D location. The surface to be conformed to can be further qualified by the Property Value that has been extended.
2. A tree canopy that conforms to multiple, or continuous LOD terrain. The entire collection of tree canopy Polygons and the tree wall Polygons around the canopy is aggregated into a Classification Related Geometry, which is associated with an Areal Feature.

   Each Vertex of the Polygons representing the tree wall around the canopy uses Conformal Behavior. The Conformal Behavior of each Vertex on the ground has parallel_gravity = SE_FALSE and offset_distance = 0, while the Conformal Behavior of the Vertices at the top has parallel_gravity = SE_TRUE and a positive offset_distance indicating the height of the tree wall. Each Vertex of the Polygons representing the tree canopy would have a Conformal Behavior with parallel_gravity = SE_TRUE and offset_distance indicating the height of the tree canopy.

3. An airplane Model might have Geometry that represents the projected shadow. The Geometry Hierarchy containing the shadow could be given Conformal Behavior so that it will hug the nominal terrain surface.

FAQs

Why has Conformal Behavior been made into a class of its own and not implemented as a kind of Control Link?

Conformal Behavior could be achieved via a Translation Control Link with a Variable that represents a Zenith (HAT) test. We have chosen to represent this kind of behavior as a class of its own because it is a well-understood (abstracted) self-contained behavior. This is also the case with Stamp Behavior and Level of Detail. SEDRIS has generally been designed to allow for high-level abstraction as well as lower-level descriptions to exist in the same Model.

Constraints

Component of (one-way)

• optionally, some Aggregate Geometries
• optionally, some Base Vertices
• optionally, some Geometry Model Instances (notes)
• optionally, some Point Geometries

Field Elements

Notes

Component of Notes

Geometry_Model_Instance

 to allow instances (or any transformation) to be conformal
 The <Conformal Behavior> is applied after a transformation

Fields Notes

parallel_gravity

 if SE_TRUE, the direction of conformance is parallel
 to gravity; otherwise, the direction of conformance
 is orthogonal to the terrain skin

offset_distance

 distance above surface in meters