Re: [Groff] Letterspacing

[Peter Schaffter]

On Thu, Mar 27, 2014, James K. Lowden wrote:
> On Thu, 27 Mar 2014 19:29:13 -0400
> Peter Schaffter <address@hidden> wrote:
> 
> > Would it not make more sense to have groff, more or less as-is,
> > shoulder more of the burden of what we do manually, *using the same
> > strategies*, to achieve better *lines*, rather than focussing on
> > the whole paragraph?
> 
> This is an excellent idea.  Your key insight is that what you do by hand
> could be automated with very little impact on the overall system, to
> useful effect.  I doubt it's been fully explore  because the problem of
> "how to set a paragraph" is considered solved, by TeX.  
> 
> It occurs to me that an algorithm that aims only at a better line -- for
> some value of "better" -- is at a disadvantage versus the
> paragraph-at-once approach.  In considering a line, a per-line
> algorithm cannot steal letters from the previous line, the one already
> set.  The best it can do is pack more letters on the current line.  
> 
> That might be OK.  It's what you do (IIUC) manually, because too much
> whitespace is the major bugaboo.  
> 
> It also might be improved by a lookahead rule: rather than looking
> strictly at the current line, consider the potential impact on the next
> one, and perhaps "donate" a character or two to the line yet to come.  

You seem to see where I'm headed with this.  After a line is
output, groff has a buffer holding the next partially-filled line,
and the way I'm thinking, this could be put to use.

It's going to take a day or two to work out a fuller description
what I'm thinking.

-- 
Peter Schaffter
http://www.schaffter.ca