[vtkusers] 6 clipplanes reverse ?

[c.kleinhuis]

Hi,

if have a

vtkBoxWidget

which gives me 6 clipplanes ,

if i add then to a datamapper, i get the requested result, and only the 
area INSIDE
of the box is visible, but i want to get everything OUTSIDE of the box,
when inverting all the normals i just get NOTHING, is it because in reverse
mode the clipfunction does not re-activate the visibility ?

i am just wondering how to solve this problem, do i have to include a 2 
step way ?

cliping x-y-z planes first which point to the background, and then 
re-clip with the
remaining 3 planes ?

please help !

thanks in advance,
c.Kleinhuis