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2. Surface emissivity: This coefficient reflects the degree of IR radiation emitted by the surface.
3. Thermal conductivity 4. Thermal inertia: This coefficient describes the material ability to gainlose
its heat to a still-air environment.
6.4.6.4 Night Vision Goggles Image Generation
Included in the coding is the material attribution exclusive of any properties used by NVG simulation models.
6.4.6.5 Ownship-Centric Mission Functions
Visual subsystems typically provide a set of ownship-centric Mission Functions MIF for use in determining:
1. The Height Above Terrain HAT, Height Above Culture HAC, and Height Above Ocean HAO. This function may report the material type of the texel or the polygon,
and the normal of the surface immediately beneath the point. 2. Own-ship Collision Detection CD with terrain, 3D culture and moving models.
This may include long thin objects such as power lines. 3. Line Of Sight LOS and Laser Ranging Function LRF originating from the
ownship. This function may return the range, the material type and the normal of the nearest encountered element in the database. The maximum length of a requested
vector is typically limited to the paged-in database.
The mission functions provided by an IG base their computations on data that has LOD representations equivalent to those used by OTW IGs. Since the visual subsystem scene
management mechanisms are essentially slaved to the own-ship’s position, the terrain accuracy e.g., its LOD, the cultural densityLOD and the texture resolution decrease
with distance from the own-ship. As a result, the IG-based mission functions computations are best suited for own-ship functions. In cases where the data store needs
to be interrogated randomly anywhere in the gaming area, simulator client-devices such as Computer Generated Forces via a terrain server are best suited because their
architecture is not own-ship-centric.
6.4.6.6 Computer Generated Forces CGF
CGF provides a synthetic tactical environment for simulation-based training. A CGF application simulates behaviors and offers interactions between different entities within
the simulation. It models dynamics, behavior doctrines, weather conditions, communications, intelligence, weapons and sensor interactions, as well as terrain
interactions. CGF offers modeling of physics-based models in a real-time natural and electronic warfare environment for air, land and sea simulations.
Typically, CGF is able to create a realistic simulated multi-threat, time-stressed environment comprising items such as:
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1. Friendly, enemy and neutral entities operating within the gaming area 2. Interaction with weather conditions currently in the simulation
3. Entities with representative dynamics velocity, acceleration, etc., signatures, vulnerabilities, equipment, communications, sensors, and
weapons 4. CGF uses time invariant information held in CDB such as:
a. Terrain altimetry and raster imagery b. Cultural features
c. Linear vector and areal information d. Sensor signatures
e. Moving Models
6.4.6.7 Weather Simulation
