function swefBody(body:Body, ?zeroVelocities:Bool=true):void {
   if(body.space!=null && body.space.zpp_inner.midstep) throw "Error: Cannot swef body during space.step()";

   if(body.isStatic()) return;
   var b = body.zpp_inner;

   if(zeroVelocities) {
      b.velx = b.vely = b.angvel = 0;
      b.forcex = b.forcey = b.torque = 0;
   }

   if(b.component.sleeping) return;
   b.component.sleeping = true;

   if(b.space==null) return;

   if(body.isDynamic()) b.space.live.remove(b);
   else {
      b.space.kinematics.remove(b);
      b.space.staticsleep.remove(b);
   }

   var arbi = b.arbiters.begin();
   while(arbi!=null) {
      var arb = arbi.elem();
      if(!arb.cleared) {
         arb.sleeping = true;
         arb.sleep_stamp = b.space.stamp;
         if(arb.type == ZPP_Arbiter.COL) {
            var carb = arb.colarb;
            if(carb.stat) b.space.c_arbiters_true.remove(carb);
            else          b.space.c_arbiters_false.remove(carb);
         }else if(arb.type == ZPP_Arbiter.FLUID)
              b.space.f_arbiters.remove(arb.fluidarb);
         else b.space.s_arbiters.remove(arb.sensorarb);
      }
      arbi = arbi.next;
   }

   if(!b.space.bphase.is_sweep) {
      for(shape in body.shapes) {
         var s = shape.zpp_inner;
         b.space.bphase.sync(s);
      }
   }
}