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Fog VRML97 Helper 649
Avatar Size—
Specifies the user’s physical
dimensions in the world, to detect collision
distance and follow terr ain.
Collision—Specifies the allowable distance between
the user’s position and any collision geometry
before a collision is detected. For example, yo u
cansetthissothatacollisionisdetectedoneunit
in front of a wall.
Terrain—Specifies the height above t he surface to
maintain when following terrain.
Step Height—Specifies the highest object that can
be "stepped over ." If an object like a staircase has
steps that are lower than this va lue, the user can
go up.
Icon Size—Adjusts the size of the helper object in
the viewpor ts.
Fog VRML97 H elp e r
Create panel > Helpers > VRML97 > Object Type rollout
>Fog
The Fog helper lets you specify the color and range
of fog in y our VRML97 world. You can simulate
atmospheric effects by blending objects with a
color based on the objects’ distances from the
viewer. For the best visual results, the background
(which is unaffected by the fog) should be the
same color as the fog.
Pr ocedur es
To crea te a V R ML 97 Fog helper :
1.
AddaFoghelperbypressingtheFogbutton,
then click-drag in the Top viewport to create
its icon.
2. Usethecontrolstoadjustthetypeoffoginyour
VRML environment.
Interfa ce
The Fog rollout contains the following options:
Ty pe—Specifies the fog type (linear or
exponential). Linear means that the amount
of blending is a linear funct ion of t he distance,
resultinginadepth-cueingeffect.Exponential
uses an exponent ia l increase in blending, resulting
in a m ore natural fog appearance.
Co lor—Lets you select the fog color from the Color
Selector dialog.
V isibility R ange—Specifies the distance from the
viewer at which objects are totally obscured by the
fog.Thesmallerthisvalueis,thecloserthefogis
to the camera, and the less your scene is visible.
The larger this value is, the more of your scene is
visible to the camera. A value of 0 turns off the
effect, making everything in the scene visible. A
value of 0 means that there is no fog effect.
Icon Size—Adjusts the size of the helper object in
the viewpor ts.
Sound VRML97 Helper
Create panel > H elpers > VRML97 > Object Type rollout
>Sound
The Sound helper lets you place 3D (spatial) or
ambient sounds in a scene. The sound may be
locatedatapointandemitsoundinaspherical
or ellipsoid pattern. The ellipsoid is pointed in a
particular direction and may be shaped to provide