[Dev-luatex] LuaTex pagination

[Frank Mittelbach]

Am 04.08.18 um 19:44 schrieb Thomas de Vivo:
> dear dev-luatex list,
>       I'm an estimator of (La)Tex and the
> work done Donald Knuth -- as well as the work that
> you all are doing -- and I'm following this list
> since a while.
> Few time ago I have been in touch with
> Patrick Gundlach of https://www.speedata.de/en/
> a publishing system based on LuateX.
> My concern and goal would be to be able
> to control the looseness of paragraphs while
> paging a text, so to minimize widows and orphans
> in the resulting document.
> In practical terms, when the system finds that
> a widow is being produced, then it tries to make
> the relevant paragraph more dense, or even
> more than one, in order to fit all the text
> in the page. (This is not currently possible using Speedata)
> I would like to know whether LuaTex offers such
> control, on in other terms whether the pagination
> algorithm is as sophisticated as the famous
> linebreak algorithm of Tex/Latex. (thing in
> my opinion highly desirable)
> Alternatively, I would like to know what files
> I have to check in the distribution of Lua
> to reach such a result.
> Thank you and kind regards
> (Thomas)

as Hans said, there is no production code in that space, largely due to 
the fact that the problems in that space are very difficult to solve 
(often NP) and managing the real-life conflicting requirements is 
challenging. And if you restrict yourself then the class of documents 
that can be handled gets very limited.

I have done some research on that in the last couple of years and the 
result can be found at:

   https://www.latex-project.org/publications/indexbytopic/pagination/

Basically this proves that suitable results can be produced in adequate 
time spans (under reasonable conditions) but so far I have only 
published the research not any code --- doing the latter would mean 
further work that I estimate at several hundreds of hours so I'm not 
sure when that can be undertaken (unless I find sponsors for it)

frank