A Java3D application running on a particular machine could have one of
several options available to it for playing the audio image created by the
sound renderer. Perhaps the machine Java3D is executing on has more than
one sound card (e.g., one that is a Wave Table Synthesis card and the other
with accelerated sound spatialization hardware). Furthermore, suppose there
are Java3D audio device drivers that execute Java3D audio methods on each of
these specific cards. In such a case the application would have at least two
audio device drivers through which the audio could be produced. For such a
case the Java3D application must choose the audio device driver with which
sound rendering is to be performed. Once this audio device is chosen, the
application can additionally select the type of audio playback type the
rendered sound image is to be output on. The playback device (headphones or
speaker(s)) is physically connected to the port the selected device driver
The AudioDevice object interface specifies an abstract input device
that creators of Java3D class libraries would implement for a particular
device. Java3D's uses several methods to interact with specific devices.
Since all audio devices implement this consistent interface, the user
could have a portable means of initialize, set particular audio device
elements and query generic characteristics for any audio device.
Audio Playback Type
Distance to Speaker
Angular Offset of Speakers
Device Driver Specific Data
Instantiating and Registering a New Device
The API for instantiating devices is site-specific, but it consists of
a device object with a constructor and at least all of the methods
specified in the AudioDevice interface.
Once instantiated, the browser or application must register the device
with the Java3D sound scheduler by associating this device with a
PhysicalEnvironment. The setAudioDevice method introduces new devices
to the Java3D environment and the allAudioDevices method produces an
enumeration that allows examining all available devices within a Java3D
environment. See PhysicalEnvironment class for more details.
General Rules for calling AudioDevice methods:
It is illegal for an application to call any non-query AudioDevice method
if the AudioDevice is created then explicitly assigned to a
PhysicalEnvironment using PhysicalEnvironment.setAudioDevice();
When either PhysicalEnvironment.setAudioDevice() is called - including
when implicitly called by SimpleUniverse.getViewer().createAudioDevice()
- the Core creates a SoundScheduler thread which makes calls to
If an application creates it's own instance of an AudioDevice and
initializes it directly, rather than using PhysicalEnvironment.
setAudioDevice(), that application may make any AudioDevice3D methods calls
without fear of the Java 3D Core also trying to control the AudioDevice.
Under this condition it is safe to call AudioDevice non-query methods.