multi-column spread control (was Re: beginner's questions)

[Ed L Cashin <ecashin@coe.uga.edu>]

Hans Hagen <pragma@wxs.nl> writes:

...
> As an example, i just implemented, willy egger may like that, multi
> column spread control, with page imposition support for figures or
> whatever spanning a page and so. Now this is no easy topic and will
> never be, even if i write 500 pages about it. -)

By multi-column spread control do you mean the ability to have
balanced columns?

There is an issue in one of the documents that my employer wants me to
do (but they keep pulling me off the job) where there is a series of
vboxes in a two-column page.

In order for the columns to balance (i.e. have the baselines of their
bottom lines line up perfectly) the glue between the vboxes has to be
balanced in a sophisticated way.  

It's been a while since I've worked on it, but here's an example:

\setupbodyfont	[9pt]
\setupcolumns	[balance=yes]
\showmakeup

\def\myText{Maggie comes fleet foot
   	    face full of black soot
   	    talkin' that the heat put
   	    plants in the bed but
   	    the phone's tapped anyway
   	    Maggie says that many say
   	    they must bust in early May ---
   	    orders from the D. A.}
% plenty of stretch
\def\interGlue{\vskip 1ex plus 4cm minus .1ex}

\starttext
\startcolumns[n=2]
\dorecurse{7}{\vbox{\myText}\interGlue}
\stopcolumns

\blank[2*big]

\startcolumns[n=3]
\dorecurse{7}{\vbox{\myText}\interGlue}
\stopcolumns

\stoptext

... since there's lots of stretchability in the interGlue, and the
columns are set to balance, I'd expect the glue between the boxes to
stretch such that the columns were balanced.  

I know that this is a hard problem, and so I'm just wondering if
that's what you meant by spread control.

-- 
--Ed Cashin                     PGP public key:
  ecashin@coe.uga.edu           http://www.coe.uga.edu/~ecashin/pgp/