JME 3.8.0-beta1

capdevon · April 24, 2025, 8:32pm

Hi guys,
I’m looking into the AudioNode.updateGeometricState() method. I noticed that the !Float.isNaN() check for the previousWorldTranslation seems to only examine the x component. Is there a specific reason why the y and z components aren’t also checked for NaN?

github.com/jMonkeyEngine/jmonkeyengine

jme3-core/src/main/java/com/jme3/audio/AudioNode.java

master


      
          }
          
          @Override
          public void updateGeometricState() {
              super.updateGeometricState();
              if (channel < 0)
                  return;
              Vector3f currentWorldTranslation = worldTransform.getTranslation();
              if (!previousWorldTranslation.equals(currentWorldTranslation)) {
                  getRenderer().updateSourceParam(this, AudioParam.Position);
                  if (velocityFromTranslation && !Float.isNaN(previousWorldTranslation.x)) {
                      velocity.set(currentWorldTranslation)
                              .subtractLocal(previousWorldTranslation).multLocal(1f / lastTpf);
                      getRenderer().updateSourceParam(this, AudioParam.Velocity);
                  }
                  previousWorldTranslation.set(currentWorldTranslation);
              }
          }
          
          @Override
          public AudioNode clone() {

yaRnMcDonuts · April 24, 2025, 10:03pm

My best guess is that they only checked the X component for being NaN because usually a bug causing a NaN vector makes the whole vector NaN. Especially if you are just using a vector normally and are not modifying the x/y/z components individually. But depending on the use case it certainly would be possible for y or z to end up NaN while x is valid.

There is a static Vector3f.isValid() method that checks the whole vector for any NaN floats: jmonkeyengine/jme3-core/src/main/java/com/jme3/math/Vector3f.java at master · jMonkeyEngine/jmonkeyengine

So I’d say this Vector3f.isValid() check should probably be used here instead of Float.isNan(x)