Text boxes have to be printed in window 1 (because window 0 does not
allow direct character positioning). I imagine that the `box' command
generates something similar to the following assembly code:
(calculate <x> and <y>)
@set_window 1;
@set_cursor <x> <y>;
@set_text_style 1;
@print_table <address> <width> <height>;
@set_text_style 0;
@set_window 0;
But in fact that isn't quite true; if you use the -a command-line option
to see the actual assembler for a short program you'll see that it's
implemented a bit differently (partly to correctly print the text to the
transcript file, if any). But it does have a `@set_window 0;' near the
end.
-- Gareth Rees