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600 Chapter 20: Managing Scenes and Projects
Headlight—
Places a directional light at the
viewpoint. The light always points in the direction
the user is looking.
Tip: Don’t use this option if you have lights in the
scene.
V isibility Limit—Sets the far clipping plane. Any
geometry beyond this point is invisible. The
smaller this value is, the closer the clipping plane
is to the camera. The larger this value is, the more
ofyoursceneisvisibletothecamera.Avalueof0
turns off the effect, making everything in the scene
visible. Use this option to show just part of large
scenes.
Speed—Determines the speed of navigation in
units per second. Use this option to a l low the user
to travel faster, if you’re building a large world (like
acityscape),andslower,ifyou’rebuildingasmall
world (like a room).
Avatar Size—Specifies the user’s physical
dimensions in the world, to detect collision
distance and follow terrain.
Collision—Specifies the allowable distance between
the user’s position and any collision geometry
before a collision is detected. For example, you
cansetthissothatacollisionisdetectedoneunit
in front of a wall.
Terrain—Specifies t he height above the 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 value, the user can
go up.
Icon Size—Adjusts the size of the helper object in
the viewports.
Fog VR ML97 H e lp e r
Create panel > Helper s > VR ML97 > Ob ject Type rollout
>Fog
The Fog helper lets you sp e cify the color and range
of fog in your 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.
Procedures
To crea te a VR M L 97 Fog hel per:
1.
AddaFoghelperbyclickingtheFogbutton,
then click-drag in the Top viewpor t to create
its icon.
2. Usethecontrolstoadjustthetypeoffoginyour
VRML environment.
Interfa ce
The Fog rollout contains the follow ing options:
Ty pe—Specifies the fog type (linear or
exponential). Linear means that the amount
of blending is a linear funct ion of the distance,
resultinginadepth-cueingeffect.Exponential
uses an exponent ia l increase in blending, resulting
in a more natural fog appearance.
Co lor—Lets you select the fog color from the Color
Selector dialog.