Re: Length range control of the last line of paragraph

[Hans Hagen <pragma@wxs.nl>]

On 3/22/2016 9:57 PM, Jan Tosovsky wrote:
> On 2016-03-22 Hans Hagen wrote:
>> On 3/21/2016 8:14 PM, Jan Tosovsky wrote:
>>> Dear All,
>>>
>>> when paragraphs are separated by indenting the first line (instead of
>> an
>>> empty line), these rules should be followed:
>>>
>>> (1) the last line lenght is greater than the left indent
>>>       xxxxxxxxxxxxxxxx
>>>       xxxx
>>>         xxxxxxxxxxxxxx
>>>       xxxxxxxxxxxxxxxx
>>>
>>> (2) the last line is shorter than block width
>>>       xxxxxxxxxxxxxxxx
>>>       xxxxxxxxxxxxxx
>>>         xxxxxxxxxxxxxx
>>>       xxxxxxxxxxxxxxxx
>>>
>>
>> you need to keep in mind that what would work out well for one specific
>> case will not look nice in general as the last line filling is just one
>> of the aspects ... so, your last line + following first line might look
>> okay (according to whatever rules and criteria) but then, as you also
>> need to increase the tolerance and enable stretch to permit that
>> solution to be found, the rest might look like crap
>
> I (naively) thought the last line can be somehow isolated in the engine so the parfillskip settings doesn't influence the rest (too much).

well, in order to determine what the last line is tex has to construct 
the paragraph so

x x xxxxxxxx

becoming

x              x
xxxxxxxx

would be real bad

> I understand your point.
>
>>> (ad 2) This can be done using \parfillskip XXpt plus 1fil (where
>>> XX is required gap)
>>
>> setting the XXpt is tricky as it might lead to underful or overful
>> cases when that amount start interfering with an optimal solution (as it's
>> seen as acceptable overflow in some direction)
>>
>
> underful or overful where? in previous lines? I am quite lost here :-)

\starttext

\setupalign[tolerant,stretch]
\dorecurse{100}{
     \hsize\dimexpr\textwidth-#1pt\relax
     \parfillskip -4em plus 1 fill
     \input tufte
     \page
}

\stoptext

page 43

>> it's hard to envision an interface, maybe some extra key in setupalign
>>
>> \setupindenting[big] \indenting[yes]
>>
>> \edef\ward{\cldloadfile{ward}}
>>
>> \setupalign[verytolerant,stretch]
>>
>> \dorecurse{100}{
>>       \hsize\dimexpr\textwidth-#1mm\relax
>>       \parfillskip \zeropoint plus 1fil\relax
>>       \ward  \par
>>       \parfillskip \zeropoint plus \dimexpr\availablehsize-
>> 3\parindent\relax
>>       \ward  \par
>>       \startnarrower[left]
>>           \parfillskip \zeropoint plus 1fil\relax
>>           \ward \par
>>       \stopnarrower
>>       \startnarrower[left]
>>           \parfillskip \zeropoint plus
>> \dimexpr\availablehsize-3\parindent\relax
>>           \ward \par
>>       \stopnarrower
>>       \page
>> }
>
> Wow, this is cool visualization!
>
> When \zeropoint is replaced by e.g. 2em, I have what wanted originally.
>
> Could anybody explain drawbacks of such approach? I mean especially that overful magic above. I'd like to summarize this topic on Wiki.
>
> Jan
>
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to the Wiki!
>
> maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
> webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
> archive  : http://foundry.supelec.fr/projects/contextrev/
> wiki     : http://contextgarden.net
> ___________________________________________________________________________________
>


-- 

-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
       tel: 038 477 53 69 | www.pragma-ade.com | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________