public void setPositional(boolean positional) {
        this.positional = positional;
        if (channel >= 0) {
            getRenderer().updateSourceParam(this, AudioParam.IsPositional);
        }
    }
Set the audio node as positional.
The position, velocity, and distance parameters affect positional
audio nodes. Set to false if the audio node should play in "headspace".

@param positional True if the audio node should be positional, otherwise
false if it should be headspace.
jme3-core/src/main/java/com/jme3/audio/AudioNode.java