How restrict display to 1024x768 on larger screens

[Kresten Bjerg]

We have developed a stack size 3072 x 2304, thus having 9 different full screens
 available on a card, when using a 1024 x 768 screen. This works fine on such a screen.

But how can we limit the appearance on larger screens, so precisely a given of the 9 
windows, and only that, can be seen ?
Our approach suceeded with the upper left window:

on tomainwindow
  global phenowindow
  if the platform is "MacOS" then
    set the rect of this window to "0,20,1024,768"

but for the remaing 8 windows 
e.g.

on toworkplacewindow
  global phenowindow
  if the platform is "MacOS" then
    set the rect of this window to "-2047,-1520,1025,760"

it does not work:  parts of the card lying outside the specified rect  (parts of neighboring 
windows) remain visible.
We might of course camouflage those parts with an empty field, but it would  be ugly and awkward.
How can a solution be constructed, which does not imply splitting up in 9 parallel substacks?
It shall be cross-platform, for standalones.

Kresten

kresten.bjerg at psy.ku.dk          www.psy.ku.dk/bjerg