better fix for previous commit

There is no short-circuit logic in Python and division by zero gets
raised when abs(rr)==0.

modules/gui/pymod/init_spacenav.py

@@ -23,7 +23,9 @@ class SpacenavControl(QtCore.QObject):
       if r==0.0:
         return 0.0
       rr=r/abs(r)*max(0.0,abs(r)-0.9)
-      return abs(rr)>0 and rr/abs(rr)*(math.pow(1.01,abs(rr))-1.0)*40.0/self.speed or 0.0
+      if abs(rr)>0:
+        return rr/abs(rr)*(math.pow(1.01,abs(rr))-1.0)*40.0/self.speed
+      return 0.0
     if(self.trans):
       tf.ApplyXAxisTranslation(d(tx))
       tf.ApplyYAxisTranslation(d(ty))