Plays audio with positional sound effects, based on the relative position of the audio listener. Positional effects include distance attenuation, directionality, and the Doppler effect. For greater realism, a low-pass filter is applied to distant sounds. This can be disabled by setting [member attenuation_filter_cutoff_hz] to [code]20500[/code].
By default, audio is heard from the camera position. This can be changed by adding an [AudioListener3D] node to the scene and enabling it by calling [method AudioListener3D.make_current] on it.
[b]Note:[/b] Hiding an [AudioStreamPlayer3D] node does not disable its audio output. To temporarily disable an [AudioStreamPlayer3D]'s audio output, set [member volume_db] to a very low value like [code]-100[/code] (which isn't audible to human hearing).
Determines which [Area3D] layers affect the sound for reverb and audio bus effects. Areas can be used to redirect [AudioStream]s so that they play in a certain audio bus. An example of how you might use this is making a "water" area so that sounds played in the water are redirected through an audio bus to make them sound like they are being played underwater.
The cutoff frequency of the attenuation low-pass filter, in Hz. A sound above this frequency is attenuated more than a sound below this frequency. To disable this effect, set this to [code]20500[/code] as this frequency is above the human hearing limit.
Decides if audio should get quieter with distance linearly, quadratically, logarithmically, or not be affected by distance, effectively disabling attenuation.
[b]Note:[/b] When setting this property, keep in mind that no validation is performed to see if the given name matches an existing bus. This is because audio bus layouts might be loaded after this property is set. If this given name can't be resolved at runtime, it will fall back to [code]"Master"[/code].
The distance past which the sound can no longer be heard at all. Only has an effect if set to a value greater than [code]0.0[/code]. [member max_distance] works in tandem with [member unit_size]. However, unlike [member unit_size] whose behavior depends on the [member attenuation_model], [member max_distance] always works in a linear fashion. This can be used to prevent the [AudioStreamPlayer3D] from requiring audio mixing when the listener is far away, which saves CPU resources.
The maximum number of sounds this node can play at the same time. Playing additional sounds after this value is reached will cut off the oldest sounds.
Scales the panning strength for this node by multiplying the base [member ProjectSettings.audio/general/3d_panning_strength] by this factor. If the product is [code]0.0[/code] then stereo panning is disabled and the volume is the same for all channels. If the product is [code]1.0[/code] then one of the channels will be muted when the sound is located exactly to the left (or right) of the listener.
Two speaker stereo arrangements implement the [url=https://webaudio.github.io/web-audio-api/#stereopanner-algorithm]WebAudio standard for StereoPannerNode Panning[/url] where the volume is cosine of half the azimuth angle to the ear.
For other speaker arrangements such as the 5.1 and 7.1 the SPCAP (Speaker-Placement Correction Amplitude) algorithm is implemented.
The base sound level before attenuation, as a linear value.
[b]Note:[/b] This member modifies [member volume_db] for convenience. The returned value is equivalent to the result of [method @GlobalScope.db_to_linear] on [member volume_db]. Setting this member is equivalent to setting [member volume_db] to the result of [method @GlobalScope.linear_to_db] on a value.
No attenuation of loudness according to distance. The sound will still be heard positionally, unlike an [AudioStreamPlayer]. [constant ATTENUATION_DISABLED] can be combined with a [member max_distance] value greater than [code]0.0[/code] to achieve linear attenuation clamped to a sphere of a defined size.
