Re: Adjusting column width dynamically to get rid of orphans and widows

[Thomas Widmann <thomas@complexli.com>]

On 23 June 2017 at 14:21, Thomas Widmann <thomas@complexli.com> wrote:
> On 20 June 2017 at 20:33, Hans Hagen <pragma@wxs.nl> wrote:
>> On 6/20/2017 11:53 AM, Thomas Widmann wrote:
>>>
>>> On 20 June 2017 at 10:41, Henri Menke <henrimenke@gmail.com> wrote:
>>>>
>>>>
>>>> On Tue, 2017-06-20 at 09:22 +0100, Thomas Widmann wrote:
>>>>>
>>>>>
>>>>> I recently started experimenting with using ConTeXt (mkiv) for
>>>>> dictionary typesetting. It's a much
>>>>> more attractive option than plain TeX or LaTeX because of the support
>>>>> for typesetting on a grid.
>>>>>
>>>>> However, grid typesetting can easily result in a large number of orphans
>>>>> and widows, which really
>>>>> doesn't look good in a dictionary.
>>>>>
>>>>> In an ideal world, I'd want to alter the column width slightly to
>>>>> prevent them (because most
>>>>> dictionaries aren't justified, this wouldn't be very noticeable).
>>>>>
>>>>> Would it be possible to use LuaTeX to achieve this?  I.e., could one
>>>>> write some code that gets
>>>>> triggered by orphans and widows and then alters the current column width
>>>>> slightly until the
>>>>> problem disappears?  Has somebody already done this?  Or have the
>>>>> relevant TeX internals not been
>>>>> Luafied yet?
>>>>>
>>>>> I'd also be interested in other ways to solve this issue – for instance
>>>>> changing the looseness
>>>>> dynamically instead of the column width.
>>>>
>>>>
>>>> Have a look at \widowpenalty and \clubpenalty.  Also use margin kerning
>>>> and font expansion.
>>>
>>>
>>> \widowpenalty and \clubpenalty are almost useless in this context –
>>> believe me, I've tried! (I'm typesetting on a grid, with a fixed
>>> number of lines per page.) Which is why I'm looking for alternatives.
>>>
>>> Margin kerning and font expansion are definitely options, but again,
>>> my real query would be how to trigger them dynamically to avoid a
>>> widow or an orphan.
>>
>> can you make a small example showing the problem
>
> Sorry about the delay – here you go!
>
> On my computer, the first column goes on for two lines more than the
> following column, and it still produces a widow:
>
> %%% document starts here
> [...]
> %%% document ends here
>
> The thing is that there simply isn't a good way to break up a
> three-line dictionary entry, and it would be much better to play
> around with the column width, the looseness, margin kerning or other
> tools rather than having to do so.  Doing it manually is easy enough,
> but it would be much nicer if the one or more of these tools could get
> triggered automatically.

Oops, those lines didn't get wrapped very neatly.  Here's a better version:

\mainlanguage[en]

\definefontfeature
  [default][default]
  [
    protrusion=quality,
    expansion=quality,
    onum=yes,
  ]

\definestartstop [negindent] [
  before={%
    \startnarrower[left]%
    \setupindenting[-.5em,yes,first]%
    \setuphead[subject][indentnext=yes]%
  },
  after=\stopnarrower,
]

\setupbodyfont[palatino]

\setupalign[hz,hanging,tolerant]

\startsetups[grid][mypenalties]
    \setdefaultpenalties
    \setpenalties\widowpenalties{2}{10000}
    \setpenalties\clubpenalties {2}{10000}
\stopsetups

\setuplayout[grid=yes, setups=mypenalties]

\righthyphenmin=60
\lefthyphenmin=60

\def\Sblackbold#1{{\bf #1}}
\def\Sdef#1{{#1}}
\def\Sdefrf#1{{\bf #1}}
\def\ShwJNR#1{{\blue\bf #1}}
\def\Spospsmallcaps#1{{\sc #1}}
\def\Spunctuation#1{{#1}}
\def\Sxrefxrhw#1{{\bf #1}}
\def\Sgroupintro#1{{\it #1}}

\def\threeentries{\ShwJNR{headphones}\page[no]\par\-\hskip .5em%
\Spospsmallcaps{noun}\Spunctuation{ }\Sdef{a pair of small speakers
that you wear over your ears}\par\ShwJNR{heard}\page[no]\par\-\hskip.5em%
\Spospsmallcaps{verb}\Spunctuation{ }\Sgroupintro{the past tense and past
part.\ of}\Spunctuation{ }\Sxrefxrhw{hear}\par\ShwJNR{hearing}\page[no]%
\par\-\hskip .5em\Spospsmallcaps{noun}\Spunctuation{ }\Sblackbold{2}
\Spunctuation{ }\Sdef{If someone gives you a }\Sdefrf{hearing}\Sdef{,
they let you give your point of view and listen to you\par}}

\def\thirtyentries{\threeentries\threeentries\threeentries\threeentries\threeentries%
\threeentries\threeentries\threeentries\threeentries\threeentries}

\startdocument

\startmixedcolumns[balance=yes]
\raggedright
\startnegindent

\thirtyentries

\stopnegindent
\stopmixedcolumns
\placefloats
\stopdocument

Thomas
-- 
Thomas Widmann
Director
Complexli Limited
+44 789 444 3009
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