Re: [Groff] question about .rs and .nop

[Peter Schaffter]

On Wed, Sep 04, 2013, Tadziu Hoffmann wrote:
> 
> > Some years ago, I wrote about the annoyance of absolute .sp
> > requests, which do not, contrary to intuition and logic,
> > take the top of the page as their starting point but rather
> > the top of the page plus 1v.  Classic example:
> >
> >  .vs 12p
> >  .sp |6P
> >  foo
> >
> > "foo" is printed 6 picas plus an additional 12 points
> > below the top of the page, requiring .sp |6P-1v to place
> > it correctly at 6 picas.
> 
> > There'd be no need for complications like @TOP if groff had
> > an absolute spacing request that spaced sensibly to the
> > requested absolute position on the page; in other words,
> > "|6P" means "6P from the top of the page", end of story.
> 
> I guess you're annoyed because you're thinking in terms of
> baselines (which, to be fair, is how practically all low-level
> printer languages are actually designed these days).

Precisely. groff doesn't understand the notion of "baseline 0" (top
edge of the page).  As you pointed out, in the lead era, groff's
behaviour would make sense.  But as you also point out, current
thinking and conceptualization see things differently. groff's
long history means that there are a few unavoidable conceptual
anachronisms; the handling of absolute .sp requests is one of them.

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