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

[Hans Hagen <pragma@wxs.nl>]

At 11:54 AM 11/13/00 -0500, Ed L Cashin wrote:

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

No, a spread is something that crosses a page, so a figure or title that
spans a left and right page. I'll send you a sample. 

>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.  

That's called snapping. 

\starttext

\setuplayout[grid=yes] \showgrid

\setupbodyfont[9pt]

\def\myText
  {\strut 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.\strut}

\startcolumns[n=2]
  \dorecurse{7}{\snaptogrid\vbox{\myText}\blank}
\stopcolumns

\blank[2*big]

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

\stoptext

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

Actually it's not that hard, but since context tries hard to snap, it is
hard to convince it to do otherwise. What i'm currently doing is isolating
the otr code into modules. There will be a series of basic otr's like:
single column, mixed single multi, and multi, plus a mechanism to implement
your own as well as communicate with the otr. The new multi routine will
give quite some control over float placement and other trickery. It is a
combination of all kind of code snippets and ideas I collected over the
past years, so i can finally clean up my machine -) 

Hans
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                                                  Hans Hagen | PRAGMA ADE
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