Keep stack proportions when resizing

[Sean Cole (Pi)]

on resizeStack
   send "ratioSet" to me in 0.01 sec
end resizeStack

on ratioSet
   lock screen
   put the topleft of this stack into tTL
   set the width of this stack to the height of me * 1.78 -- Ratio 16:9
   set the topleft of this stack to tTL
   unlock screen
end ratioSet