Playback instance for [AudioStreamPolyphonic]. After setting the [code]stream[/code] property of [AudioStreamPlayer], [AudioStreamPlayer2D], or [AudioStreamPlayer3D], the playback instance can be obtained by calling [method AudioStreamPlayer.get_stream_playback], [method AudioStreamPlayer2D.get_stream_playback] or [method AudioStreamPlayer3D.get_stream_playback] methods.
Return true whether the stream associated with an integer ID is still playing. Check [method play_stream] for information on when this ID becomes invalid.
This ID becomes invalid when the stream ends (if it does not loop), when the [AudioStreamPlaybackPolyphonic] is stopped, or when [method stop_stream] is called.
This function returns [constant INVALID_ID] if the amount of streams currently playing equals [member AudioStreamPolyphonic.polyphony]. If you need a higher amount of maximum polyphony, raise this value.
</description>
</method>
<methodname="set_stream_pitch_scale">
<returntype="void"/>
<paramindex="0"name="stream"type="int"/>
<paramindex="1"name="pitch_scale"type="float"/>
<description>
Change the stream pitch scale. The [param stream] argument is an integer ID returned by [method play_stream].
</description>
</method>
<methodname="set_stream_volume">
<returntype="void"/>
<paramindex="0"name="stream"type="int"/>
<paramindex="1"name="volume_db"type="float"/>
<description>
Change the stream volume (in db). The [param stream] argument is an integer ID returned by [method play_stream].
</description>
</method>
<methodname="stop_stream">
<returntype="void"/>
<paramindex="0"name="stream"type="int"/>
<description>
Stop a stream. The [param stream] argument is an integer ID returned by [method play_stream], which becomes invalid after calling this function.
</description>
</method>
</methods>
<constants>
<constantname="INVALID_ID"value="-1">
Returned by [method play_stream] in case it could not allocate a stream for playback.