[NTG-context] \setuplayout --- what do parameters mean?

[David Arnold]

All,

When I see something like this:

\setuplayout
  [topspace=10pt,
   header=40pt,
   headerdistance=20pt,
   height=middle,
   footerdistance=20pt,
   footer=0pt,
   bottomdistance=10pt,
   bottom=20pt,
   bottomspace=40pt,
   backspace=30pt,
   width=middle]

I have a hard time working out what it means. I know I can do \showframe,
but that doesn't indicate everything I need to see. Does anyone have a
macro that shows ALL of these parameters in a visual way, similar to that
on page 182 of the Latex User Guide, 2nd ed., Lamport?