SoListener: The solistener class defines listener attributes used when rendering sound. when rendering geometry, one needs to have a camera defining certain attributes related to vieweing. the solistener plays a similar role when it comes to rendering audio.

SYNOPSIS

#include <Inventor/nodes/SoListener.h>

Inherits SoNode.

Public Member Functions

virtual SoType getTypeId (void) const

Returns the type identification of an object derived from a class inheriting SoBase. This is used for run-time type checking and 'downward' casting. SoListener ()

Static Public Member Functions

static SoType getClassTypeId (void)

static void initClass ()

Public Attributes

SoSFVec3f position

SoSFRotation orientation

SoSFFloat gain

SoSFVec3f dopplerVelocity

SoSFFloat dopplerFactor

Protected Member Functions

virtual const SoFieldData * getFieldData (void) const

virtual void audioRender (class SoAudioRenderAction *action)

virtual ~SoListener ()

Static Protected Member Functions

static const SoFieldData ** getFieldDataPtr (void)

Additional Inherited Members

Detailed Description

The SoListener class defines listener attributes used when rendering sound.

When rendering geometry, one needs to have a camera defining certain attributes related to vieweing. The SoListener plays a similar role when it comes to rendering audio.

If no SoListener has been encountered when a SoVRMLSound node renders itself, it will use the position and the orientation of the current camera. In this case, a gain of 1, a dopplerVelocity of 0 and a dopplerFactor of 0 will be assumed.

Coin does not currently support doppler effects, so the dopplerVelocity and dopplerFactor fields are currently ignored.

FILE FORMAT/DEFAULTS:

Listener {
    position 0 0 0
    orientation 0 0 1  0
    dopplerVelocity 0 0 0
    dopplerFactor 0
    gain 1
}

See also:

SoVRMLSound

Constructor & Destructor Documentation

SoListener::SoListener ()

Contructor.

SoListener::~SoListener ()\fC [protected]\fP, \fC [virtual]\fP

Destructor.

Member Function Documentation

\fBSoType\fP SoListener::getTypeId (void) const\fC [virtual]\fP

Returns the type identification of an object derived from a class inheriting SoBase. This is used for run-time type checking and 'downward' casting. Usage example:

void foo(SoNode * node)
{
  if (node->getTypeId() == SoFile::getClassTypeId()) {
    SoFile * filenode = (SoFile *)node;  // safe downward cast, knows the type
  }
}

For application programmers wanting to extend the library with new nodes, engines, nodekits, draggers or others: this method needs to be overridden in all subclasses. This is typically done as part of setting up the full type system for extension classes, which is usually accomplished by using the pre-defined macros available through for instance Inventor/nodes/SoSubNode.h (SO_NODE_INIT_CLASS and SO_NODE_CONSTRUCTOR for node classes), Inventor/engines/SoSubEngine.h (for engine classes) and so on.

For more information on writing Coin extensions, see the class documentation of the toplevel superclasses for the various class groups.

Implements SoBase.

const \fBSoFieldData\fP * SoListener::getFieldData (void) const\fC [protected]\fP, \fC [virtual]\fP

Returns a pointer to the class-wide field data storage object for this instance. If no fields are present, returns NULL.

Reimplemented from SoFieldContainer.

void SoListener::audioRender (class \fBSoAudioRenderAction\fP *action)\fC [protected]\fP, \fC [virtual]\fP

Action method for SoAudioRenderAction.

Does common processing for SoAudioRenderAction action instances.

Reimplemented from SoNode.

Member Data Documentation

\fBSoSFVec3f\fP SoListener::position

Listener position. Defaults to (0.0f, 0.0f, 0.0f).

\fBSoSFVec3f\fP SoListener::orientation

Listener orientation specified as a rotation value from the default orientation where the listener is looking pointing along the negative z-axis, with 'up' along the positive y-axis. Defaults to SbRotation(SbVec3f(0.0f, 0.0f, 1.0f), 0.0f).

\fBSoSFVec3f\fP SoListener::gain

The gain is a scalar amplitude multiplier that attenuates all sounds in the scene. The legal range is [0.0f, any), however a gain value > 1.0f might be clamped to 1.0f by the audio device. Defaults to 1.0f, meaning that the sound is un-attenuated. A gain value of 0.5f would be equivalent to a 6dB attenuation. If gain is set to 0.0f, no sound can be heard.

\fBSoSFVec3f\fP SoListener::dopplerVelocity

The doppler velocity of the sound. It is the application programmer's responsibility to set this value. Coin does not update this value automatically based on changes in a sound's position. The default value is (0.0f, 0.0f, 0.0f).

Coin does not yet support doppler effects.

\fBSoSFFloat\fP SoListener::dopplerFactor

The amount of doppler effect applied to the sound. The legal range is [0.0f, any>, where 0.0f is default and disable all doppler effects, 1.0f would be a typical value for this field if doppler effects are required.