Class Name: GC Location 3D

Superclass - Location 3D

Definition

A coordinate within the Geocentric (GC) 3D Spatial Reference Frame.

The GC SRF is based on a Cartesian coordinate system with 3 orthogonal axes and an origin at the center of mass of the Object Reference Model/Earth Reference Model (ORM/ERM) as defined by the World Geodetic System (WGS) 1984 ellipsoid. The X axis is defined as pointing to the Prime (Greenwich) Meridian in the Equatorial plane. The Z axis is defined as the semi-minor (polar) axis (coincident with the ORM/ERM rotational axis) and pointing north. The Y axis is defined as orthogonal to he other two (and in the ORM/ERM equatorial plane) so as to form a right-handed orthogonal set. Locations are defined as {x, y, z} triplets in meters from the origin (Earth mass-center).

See the SEDRIS Spatial Reference Model (SRM) for additional details.

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Example

1. GC is used in Distributed Interactive Simulation (DIS) to define the position of all simulated entities.
2. GC provides a convenient system for relating the spatial reference frame of a rotating Earth to a variety of Earth mass-centered inertial spatial reference frames.

FAQs

Constraints

• Environment Root Spatial Reference Frame
• Locations Under Model

Component of (one-way)(inherited)

• optionally, some Arcs
• optionally, some Base Perimeter Data
• optionally, some Base Reference Vectors
• optionally, some Directional Light Behaviors
• optionally, a Distance Level of Detail Data (notes)
• optionally, some Ellipses
• optionally, some Elliptic Cylinders
• optionally, some Feature Edges
• optionally, a Feature Node
• optionally, some Image Anchors
• optionally, some Labels
• optionally, a Location Table
• optionally, some Morph Points
• optionally, some Point Geometries
• optionally, some Property Grid Hook Points
• optionally, a Reference Origin
• optionally, some Spatial Domains
• optionally, some Spatial Index Related Feature Topologies
• optionally, some Spatial Index Related Features
• optionally, some Spatial Index Related Geometries
• optionally, some Tack Points
• optionally, some Vertices
• optionally, some Vertex with Component Indices
• optionally, some World 3X3s
• optionally, some World Transformations
• optionally, an Attachment Point
• optionally, some Center of Buoyancies
• optionally, some Center of Mass
• optionally, some Center of Pressures
• optionally, a Contact Point
• optionally, some Positional Lights
• optionally, some Separating Planes
• optionally, some Sound Instances
• optionally, some Stamp Behaviors
• optionally, some Volumes
• optionally, some Volume Level of Detail Data
• optionally, some Volume Light Behaviors

Field Elements

Notes

Component of Notes

Distance_Level_of_Detail_Data

 the center point for the LOD test

Fields Notes

x

 in meters; positive towards Prime Meridian in equatorial
 plane; origin at mass-center

y

 in meters; positive towards 90 degrees east of Prime Meridian
 in equatorial plane; origin at mass-center

z

 in meters; positive northwards along rotational axis origin
 at mass-center