Re: drawing commands have no impact on diversion height

[Steve Izma]

On Thu, Jun 08, 2023 at 02:29:04PM -0400, Steve Izma wrote:
> Subject: Re: drawing commands have no impact on diversion height
> 
> On Fri, Jun 02, 2023 at 01:35:22PM -0500, G. Branden Robinson wrote:
> > Subject: drawing commands have no impact on diversion height
> > 
> > I find myself offended by the fact that \D drawing commands update the
> > diversion width register `dl`, but have no impact on the diversion
> > height register `dn`.

When I first tested this with the following modified script:
> ------------------------------------------------------------
> .sp 1i
> Hello, world.
> .sp
> Pardon me a moment while I create a diversion.
> .br
> .di DD
> ' \" \D'c 1i'
> .nf
> \H'72'This is a test.\H'0'
> Line 2 of this test.
> .sp -2v
> Line 3 of this test.
> .br
> .di
> .fi
> Okay, I'm back.
> .sp
> Now, let's have a look at that diversion;
> it's \n(dn tall by \n(dl wide. \" 12000, 72000 in PostScript
> .sp 0.5i-0.5v
> .DD
> This line starts after the output of the diversion.
> .sp 0.5i
> All done.
> ------------------------------------------------------------

I didn't get increased clarity on the \n[dn] problem (still
working on it in my copious spare time), but I was perplexed by
this:

> *But* the ending of the diversion seemed to swallow the EOL of
> the diversion's last output line, or the .br, or something. As a
> result, the first line after the diversion acts as if it's a
> continuation of the input to the diversion (see attached PS
> file). If I add a .br immediately after the .DD, I get the
> expected results, but that seems unnecessary and unpredictable to
> me, almost as if a .chop got silently applied by .di

I've now realized that this problem resulted from the diversion
being re-processed due to the lack of a .nf during it's output in
both Branden's and my script. In other words, when the diversion
is output in fill mode, all line endings are removed and line
justification is redone.

Still experimenting with \n[.h] and \n[dn].

        -- Steve

-- 
Steve Izma
-
Home: 35 Locust St., Kitchener, Ontario, Canada  N2H 1W6
E-mail: sizma@golden.net  phone: 519-745-1313
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==
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