jMonkeyEngine.org

I’ve read a previous post where someone had problems with 3D audio (http://jmonkeyengine.org/groups/sound/forum/topic/hello-audio-without-3d-effect/). I’m trying it now with the latest nightly release, on two separate computers, and I’m not having a lot of luck. Even if I don’t get a full 3D effect, I assume I should at least be hearing a difference between left and right ear… (I’m on Windows 7, 64 bit.)

I’ve written a reusable test caseA small, self-contained application class that shows the effects of a problem. It should use only default assets so that it can be posted in the forum in code tags and run as-is by the developers., below, where the sound should spin round the camera. Have I made any mistakes?

Cheers,
Peter.

package mygame;

import com.jme3.app.SimpleApplication;
import com.jme3.audio.AudioNode;
import com.jme3.audio.Environment;
import com.jme3.material.Material;
import com.jme3.math.ColorRGBA;
import com.jme3.math.Vector3f;
import com.jme3.renderer.RenderManager;
import com.jme3.scene.Geometry;
import com.jme3.scene.shape.Box;
import org.lwjgl.openal.AL10;
import org.lwjgl.openal.AL11;

public class Main extends SimpleApplication {

    // Cube geometry
    Geometry geom;
    // Point on the circle to spin the cube
    int radius = 20;
    int numPoints = 10000;
    int point = 0;
    float alpha;

    // Audio node
    private AudioNode cubeAudio;    

    public static void main(String[] args) {
        Main app = new Main();
        app.start();
    }

    @Override
    public void simpleInitApp() {
        // Create spinning cube
        Box b = new Box(Vector3f.ZERO, 1, 1, 1);
        geom = new Geometry("Box", b);
        Material mat = new Material(assetManager, "Common/MatDefs/Misc/Unshaded.j3md");
        mat.setColor("Color", ColorRGBA.Blue);
        geom.setMaterial(mat);
        rootNode.attachChild(geom);

        // Set up audio
        audioRenderer.setEnvironment(Environment.Dungeon);
        AL10.alDistanceModel(AL11.AL_EXPONENT_DISTANCE);
        cubeAudio  = new AudioNode(assetManager, "Sound/Effects/Beep.ogg", false);
        cubeAudio.setPositional(true);
        cubeAudio.setLooping(true);
        cubeAudio.setReverbEnabled(true);
        cubeAudio.setRefDistance(100000000);
        cubeAudio.setMaxDistance(100000000);
        cubeAudio.play(); 

        alpha = (float)Math.PI*2/numPoints;
    }

    @Override
    public void simpleUpdate(float tpf) {
        // Move the cube to a new location
        float theta = alpha * point;
        float x = (float) Math.cos( theta ) * radius;
        float z = (float) Math.sin( theta ) * radius;
        geom.setLocalTranslation(x, 0, z);
        point = point + 1;
        if (point > numPoints) point = 0;

        // Update sound source location
        cubeAudio.setLocalTranslation(x, 0, z);
        cubeAudio.updateGeometricState();    

        // Update listener location
        listener.setLocation(cam.getLocation());
        listener.setRotation(cam.getRotation());
    }

    @Override
    public void simpleRender(RenderManager rm) {  }
}

Thanks,
Reducing refDistance and maxDistance to sensible values makes the effect work, albeit subtle. (My thinking was that by setting them to high values, only direction rather than distance would have an effect.)

If anyone knows any tricks to boost the illusion – to give a seriously strong effect similar to http://gprime.net/flash.php/soundimmersion – I’d be delighted to hear

@pspeed said:Also… this:
AL10.alDistanceModel(AL11.AL_EXPONENT_DISTANCE);

Is probably not a great idea.

According to the AL10 documentation, the only legal arguments are the constants provided for in AL10.

In any event, you shouldn’t be needing to call GL or AL functionality directly when using jME!

BTW, I checked out Mythruna’s code and apparently I just leave ref distance and max distance at the default values and get a pretty good positional audio.

…I do turn off reverb though as it can confuse the sound I hear. At least when I was testing it.