Release Notes MicroImages, Inc. TNT-Products V. 6.8

RELEASE OF RV6.8 TNT PRODUCTS
overhead. These effects for a variety of different symbols and symbol layers are illus-
trated in the attac hed color plate entitled Billboard Overlays in TNTsim3D.
Floating Symbols and Stalks.
Some kinds of symbol designs are not easy to observe if they are positioned directly on
the texture surface. Thus, each billboard symbol can be offset to float above or below
the associated terrain layer by a height field in the symbol tables. Offset billboard symbols
are automatically connected to their map position on the surface by a vertical line
called a stalk. Since symbols can be offset either above or below the surface, the stalk
can lead downward to the surface (like a flag pole) or upward to the surface (like a
shaft). Stalks are managed in the symbol tables like lines in TNTmips and can have
line styles such as
color, width, and so on.
Vertical
Exaggeration.
If you apply vertical exaggeration to the terrain relief in your geosim, the Options/Terrain
panel provides a toggle button that lets you choose whether or not to apply the same
exaggeration factor to Billboard and Stalk layers. If you turn this toggle on, the lengths
of the stalks are exaggerated, but the billboard symbols themselves retain their original
proportions.
Vo lumes-of-Interest.
Spherical Volumes.
You can display layers in your geosim that show spherical Volumes-of-Interest that have
been created from 2D or 3D vector points. Solid or transparent spherical shapes are
rendered around each point location in each frame. These shapes might represent the
range of a cell phone or wireless network transponder, the flight danger zone for a hospital
helicopter pad, the safe glide path for an airport approach, a radar’s sweep area,
and so on. Examples of the kinds of spherical VOIs that can make up a layer in
TNTsim3D RV6.8 are illustrated in the attached color plate entitled Volume-of-Interest
Overlays in TNTsim3D.
Tabular Structure.
Each spherical VOI is defined in a relational table structure that is used to draw its VOIs
in each geosim frame. VOIs are stored in the same database as the Billboard and Stalk
symbol layers. Each individual VOI is defined in this structure as a point in space together
with all the other parameters needed to define how it will be rendered by DirectX
or OpenGL. These include many optional parameters such as its color and transparency,
a surface grid including its spacing and color, inner/outer radius, max/min azimuth
angles for sectors,
and others. You can view (but not edit) the parameters of each VOI
using the View Table option on the Layer menu in the TNTsim3D main view.
Transparency.
The color and default transparency for each VOI is determined by the color and transparency
set for its individual parent point symbol in TNTmips. The color for VOI surface
grids is determined by the default (All Same) color for all point symbols in the parent
vector object. The preset VOI transparency can be overridden and changed during the
geosim using a control on the Options/Extras tabbed panel. The texture and other layers
can be seen inside of a transparent VOI, though colored by the intervening VOI sur-
MICROIMAGES MEMO 32
5 MAY 2003