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Billboard VRML97 Helper 607
2.
Enter the location of the sound file (.wav or
.mid)youwanttouseintheURLtextbox.
Inter face
The rollout contains the following options:
URL—Specifies the location/file name of the sound
to use. Either.wav (wa veform) or .mid (MIDI)
files can be used, but MIDI sound files may not be
spatialized. Some browsers do not support MIDI.
Description—Lets you enter a text description of
the sound, which is displayed by some browsers.
Pitch—Setstherelativepitchofthesound.1.0is
normal pitch, and 0.5 is one octave lower than
normal.
Loop—Repeats the sound.
Start on Wor ld Load—Starts playing the sound as
soon as the world is loaded into the browser.
Icon Size—Determines the size of the AudioClip
helper in the scene.
Billboard V RML97 Helper
Create panel > Helpers > VRML97 > Object Type rollout >
Billboard
The Billboard helper lets you create geometry
that is camera-aligned in the VRML97 browser.
The objects always align to the view point in the
VRML97 browser.
AnygeometrylinkedtotheBillboardhelperwill
rotate about the local Z axis of the helper object to
face the viewer. Since it rotates about the location
of the Billboard, it is best to center the Billboard on
the object that you will link to it.
ThedirectionofthenegativeYaxisoftheobject,
which will be its front, is aligned with the negative
Y axis of the helper, and will be the Billboard
surface that always faces the viewer. This is the side
usually seen from the default c amera p osition.
Procedures
To create a B illboard helper object:
1.
Press the Billboard button and click-drag in the
Top viewport to create the helper.
2. Link object(s) to the billboard to k eep them
aligned with the camera.
Interfa ce
The Billboard rollout contains the following
option:
Screen Al ignment—Keeps the geometry linked to
the Billboard helper alig ned, even when the v iewer
elevates, pitches, and rolls.