Hi everyone,
I’ve recently been working on enhancing the sound system within the demo I am currently developing. I’ve found that the current jME API appears to lack support for implementing custom AudioRenderer solutions beyond the existing lwjgl and joal implementations. This presents a significant limitation. Furthermore, extending the functionality of the current AudioRenderer seems to require modifications to the engine’s core codebase, which is challenging given the complexity of the existing source.
JmeDesktopSystem.newAudioRenderer()
// API doesn't really allow for writing custom AudioRenderer
// implementations using AppSettings.
@Override
public AudioRenderer newAudioRenderer(AppSettings settings) {
initialize(settings);
AL al;
ALC alc;
EFX efx;
if (settings.getAudioRenderer().startsWith("LWJGL")) {
al = newObject("com.jme3.audio.lwjgl.LwjglAL");
alc = newObject("com.jme3.audio.lwjgl.LwjglALC");
efx = newObject("com.jme3.audio.lwjgl.LwjglEFX");
} else if (settings.getAudioRenderer().startsWith("JOAL")) {
al = newObject("com.jme3.audio.joal.JoalAL");
alc = newObject("com.jme3.audio.joal.JoalALC");
efx = newObject("com.jme3.audio.joal.JoalEFX");
} else {
throw new UnsupportedOperationException(
"Unrecognizable audio renderer specified: "
+ settings.getAudioRenderer());
}
if (al == null || alc == null || efx == null) {
return null;
}
return new ALAudioRenderer(al, alc, efx);
}
// why put a Listener object in the LegacyApplication class?
// why does the Listener class have such a generic, non-specialized name?
// why not AudioListener?
private void initAudio() {
if (settings.getAudioRenderer() != null && context.getType() != Type.Headless) {
audioRenderer = JmeSystem.newAudioRenderer(settings);
audioRenderer.initialize();
AudioContext.setAudioRenderer(audioRenderer);
listener = new Listener();
audioRenderer.setListener(listener);
}
}
It also became apparent that many capabilities of the OpenAL library, such as Effects and Sound Filters, have not been fully utilized in the current jme integration.
ALAudioRenderer.setEnvironment()
// ALAudioRenderer only supports ReverbEffect (alias Environment)
@Override
public void setEnvironment(Environment env) {
checkDead();
synchronized (threadLock) {
if (audioDisabled || !supportEfx) {
return;
}
efx.alEffectf(reverbFx, EFX.AL_REVERB_DENSITY, env.getDensity());
efx.alEffectf(reverbFx, EFX.AL_REVERB_DIFFUSION, env.getDiffusion());
efx.alEffectf(reverbFx, EFX.AL_REVERB_GAIN, env.getGain());
efx.alEffectf(reverbFx, EFX.AL_REVERB_GAINHF, env.getGainHf());
efx.alEffectf(reverbFx, EFX.AL_REVERB_DECAY_TIME, env.getDecayTime());
efx.alEffectf(reverbFx, EFX.AL_REVERB_DECAY_HFRATIO, env.getDecayHFRatio());
efx.alEffectf(reverbFx, EFX.AL_REVERB_REFLECTIONS_GAIN, env.getReflectGain());
efx.alEffectf(reverbFx, EFX.AL_REVERB_REFLECTIONS_DELAY, env.getReflectDelay());
efx.alEffectf(reverbFx, EFX.AL_REVERB_LATE_REVERB_GAIN, env.getLateReverbGain());
efx.alEffectf(reverbFx, EFX.AL_REVERB_LATE_REVERB_DELAY, env.getLateReverbDelay());
efx.alEffectf(reverbFx, EFX.AL_REVERB_AIR_ABSORPTION_GAINHF, env.getAirAbsorbGainHf());
efx.alEffectf(reverbFx, EFX.AL_REVERB_ROOM_ROLLOFF_FACTOR, env.getRoomRolloffFactor());
// attach effect to slot
efx.alAuxiliaryEffectSloti(reverbFxSlot, EFX.AL_EFFECTSLOT_EFFECT, reverbFx);
}
}
ALAudioRenderer.updateFilter()
// ALAudioRenderer only supports LowPassFilter
private void updateFilter(Filter f) {
int id = f.getId();
if (id == -1) {
ib.position(0).limit(1);
efx.alGenFilters(1, ib);
id = ib.get(0);
f.setId(id);
objManager.registerObject(f);
}
if (f instanceof LowPassFilter) {
LowPassFilter lpf = (LowPassFilter) f;
efx.alFilteri(id, EFX.AL_FILTER_TYPE, EFX.AL_FILTER_LOWPASS);
efx.alFilterf(id, EFX.AL_LOWPASS_GAIN, lpf.getVolume());
efx.alFilterf(id, EFX.AL_LOWPASS_GAINHF, lpf.getHighFreqVolume());
} else {
throw new UnsupportedOperationException("Filter type unsupported: "
+ f.getClass().getName());
}
f.clearUpdateNeeded();
}
I temporarily paused development on the demo to thoroughly review the OpenAL documentation and identify untapped potential.
Based on my findings, I discovered a method to bypass the standard AudioRenderer initialization process and integrate my own custom SoundManager, offering a significantly simpler and more modular API. Attached is a screenshot showcasing the functionality I have currently implemented:
public static void main(String[] args) {
AppSettings settings = new AppSettings(true);
settings.setResolution(640, 480);
settings.setAudioRenderer(null); // disable jME AudioRenderer
Test_SoundManager app = new Test_SoundManager();
app.setSettings(settings);
app.setShowSettings(false);
app.setPauseOnLostFocus(false);
app.start();
}
At this stage, I am still working on integrating multichannel audio management, audio streams, and a dedicated WAV loader. However, I have successfully implemented:
SoundManagerSoundSourceSoundBufferSoundListenerAudioEffects: Chorus, Compressor, Distortion, Echo, Flanger, PitchShift, ReverbAudioFilters: LowPassFilter & HighPassFilter- the capability to modify the distance attenuation model equation.
OGGLoader
I am eager to explore the extent to which I can improve the audio system and integrate advanced features, drawing inspiration from concepts found in engines like Unity, specifically the AudioMixer and AudioMixerGroup.
Edit:
Maybe something to think about for jme4
In the meantime, here is the new look of my editor for the current jme AudioNodes:
