[JAVA3D] How long is a pickray?

[Chad Zalkin]

I created my application to implement gravity.  I'm sending a pickray directly down from the viewplatform.  If the ray hits the ground, and the ground is below the "feet" you "fall" down the y axis.    The problem is that when the avatar is far from any pickable objects, the ray fails to pick anything and I'm left floating in midair.  When I float over an object that is closer, the whole thing works and I fall with proper acceleration and everything.   I thought a pickray was infinite, why doesn't it work?  Is this a bounds issue?  What node would need a bigger bounding box?   Thanks Chad Zalkin