// Distance Equation
// this will make the rigid body solver activve when Effector is
//  within 3 grid units of the solver's center of mass (pivot point)

float $dx = abs(Effector.translateX-rigidBody50.centerOfMassX);
float $dy = abs(Effector.translateY-rigidBody50.centerOfMassY);
float $dz = abs(Effector.translateZ-rigidBody50.centerOfMassZ);

rigidBody50.distance = sqrt(($dx*$dx)+($dy*$dy)+($dz*$dz));

// Reset the rigid body on the first frame

if(`currentTime -q` == `playbackOptions -q -min`)
   rigidBody50.active = 0;
else
{
// Make the rigid body solver active when Effector is
// close enough to the solver’s center of mass

   if (rigidBody50.distance <= rigidBody50.activeDist)
   {
      rigidBody50.active = 1;
      rigidBody50.ignore = 0;
   }

// Factor this solver out when Effector is too far away
   if (rigidBody50.distance >= rigidBody50.maxDist)
      rigidBody50.ignore = 1;
}