On Tue, 07 Aug 2012 00:22:08 +0200, Peter Muenster wrote:

The distance is not 0pt here (MKIV):

--8<---------------cut here---------------start------------->8--- \starttext \startcolumns[distance=0pt] \input tufte \stopcolumns \stoptext --8<---------------cut here---------------end--------------->8---

It would appear that this problem is still the case, as of the following version:

$ context --version | sed -n 2p;5p mtx-context | ConTeXt Process Management 0.63 mtx-context | current version: 2016.09.24 12:40

In particular, Peter's example produces something like the following: (I'm assuming these 90-character-plus-CRLF lines made it through the Internet; if they did not make it, then someone's email-processing software is non-conformant, so shame on him!)

We thrive in information-thick worlds screen, pigeonhole, pick over, sort, inte- because of our marvelous and every- grate, blend, inspect, filter, lump, skip, day capacity to select, edit, single smooth, chunk, average, approximate, out, structure, highlight, group, pair, cluster, aggregate, outline, summarize, merge, harmonize, synthesize, focus, or- itemize, review, dip into, flip through, ganize, condense, reduce, boil down, browse, glance into, leaf through, skim, choose, categorize, catalog, classify, refine, enumerate, glean, synopsize, list, abstract, scan, look into, ideal- winnow the wheat from the chaff and ize, isolate, discriminate, distinguish, separate the sheep from the goats.

However, a person whose thoughts are governed by reasonable logic might instead expect the result to look more like this:

We thrive in information-thick worldsscreen, pigeonhole, pick over, sort, inte- because of our marvelous and every-grate, blend, inspect, filter, lump, skip, day capacity to select, edit, singlesmooth, chunk, average, approximate, out, structure, highlight, group, pair,cluster, aggregate, outline, summarize, merge, harmonize, synthesize, focus, or-itemize, review, dip into, flip through, ganize, condense, reduce, boil down,browse, glance into, leaf through, skim, choose, categorize, catalog, classify,refine, enumerate, glean, synopsize, list, abstract, scan, look into, ideal-winnow the wheat from the chaff and ize, isolate, discriminate, distinguish,separate the sheep from the goats.

The ConTeXt facilities in question are [mostly] defined here:

"$TEXROOT"/texmf-context/tex/context/base/mkiv/page-mul.mkiv

After a not-so-cursory review, it seems to me that the problem is a result of [probably erroneous] references [in various calculations] to the `offset' parameter, which is presumably a vestigial growth inherited from `\setupframed'.

Fortunately, meddling by this `offset' parameter can be explicitly nullfied via including `offset=0pt' in the setup parameters for the `\startcolumns' command; that is, in order to get the results that Peter expected, modify Peter's example to be this:

--8<---------------cut here---------------start------------->8--- \starttext \startcolumns[offset=0pt,distance=0pt] \input tufte \stopcolumns \stoptext --8<---------------cut here---------------end--------------->8---

If you now include `rule=on', then you get:

We thrive in information-thick worlds|screen, pigeonhole, pick over, sort, inte- because of our marvelous and every-|grate, blend, inspect, filter, lump, skip, day capacity to select, edit, single|smooth, chunk, average, approximate, out, structure, highlight, group, pair,|cluster, aggregate, outline, summarize, merge, harmonize, synthesize, focus, or-|itemize, review, dip into, flip through, ganize, condense, reduce, boil down,|browse, glance into, leaf through, skim, choose, categorize, catalog, classify,|refine, enumerate, glean, synopsize, list, abstract, scan, look into, ideal-|winnow the wheat from the chaff and ize, isolate, discriminate, distinguish,|separate the sheep from the goats.

If you now replace `distance=0pt' with `distance=2ex', then you get the following (I chose `2ex', so as to be able to represent the results more accurately in plain text):

We thrive in information-thick worlds | screen, pigeonhole, pick over, sort, inte- because of our marvelous and every- | grate, blend, inspect, filter, lump, skip, day capacity to select, edit, single | smooth, chunk, average, approximate, out, structure, highlight, group, pair, | cluster, aggregate, outline, summarize, merge, harmonize, synthesize, focus, or- | itemize, review, dip into, flip through, ganize, condense, reduce, boil down, | browse, glance into, leaf through, skim, choose, categorize, catalog, classify, | refine, enumerate, glean, synopsize, list, abstract, scan, look into, ideal- | winnow the wheat from the chaff and ize, isolate, discriminate, distinguish, | separate the sheep from the goats.

While setting `offset=0pt' will work for existing distributions, I suggest removing the `offset' cruft from MKIV altogether, especially as it doesn't seem to be useful. That way, at least one thing in the world of TeX will work without requiring some abstruse incantation.

At the end of this email, there is included a patch that makes the changes I propose; to apply it, just save this email as:

/path/to/patch

and then do the following:

$ cd "$TEXROOT" $ patch -p0 < /path/to/patch

Note that `\setupmixedcolumns[distance=0pt]' works as expected for those facilities to which it applies; it should be documented more obviously (a sentiment that is unfortunately relevant to much of ConTeXt, let alone TeX itself).

Sincerely, Michael Witten

--- texmf-context/tex/context/base/mkiv/page-mul.mkiv +++ texmf-context/tex/context/base/mkiv/page-mul.mkiv @@ -149,7 +149,6 @@ \newdimen \d_page_mul_distance \newdimen \d_page_mul_leftskip \newdimen \d_page_mul_rightskip -\newdimen \d_page_mul_offset \newdimen \d_page_mul_forced_height \newdimen \d_page_mul_used_width \newdimen \d_page_mul_temp @@ -193,7 +192,6 @@ \relax \d_page_mul_used_width\dimexpr \d_page_mul_available_width/\nofcolumns - -\d_page_mul_offset*\plustwo \relax \textwidth\d_page_mul_used_width % needs thinking ... grouping etc \hsize\d_page_mul_used_width} @@ -274,7 +272,6 @@ \unexpanded\def\page_mul_set_n_of_lines {\settotalinsertionheight \d_page_mul_temp\dimexpr - -\d_page_mul_offset*\plustwo +\textheight \ifdim\d_page_mul_preceding_height>\zeropoint -\d_page_mul_preceding_height \fi -\totalinsertionheight @@ -1608,7 +1605,6 @@ \ifx\p_option\v!background \let\finishcolumnbox\backgroundfinishcolumnbox \fi - \d_page_mul_offset\columnsparameter\c!offset\relax \edef\p_command{\columnsparameter\c!command}% \ifx\p_command\empty \else \let\postprocesscolumnline\p_command @@ -1690,8 +1686,7 @@ \c!align=\v!text, \c!blank={\v!line,\v!fixed}, \c!option=, - \c!rulethickness=\linewidth, - \c!offset=.5\bodyfontsize] + \c!rulethickness=\linewidth]

%D New: only at start of columns; may change ! Rather interwoven and therefore %D to be integrated when the multi column modules are merged. @@ -1704,7 +1699,6 @@

\setupcolumnspan [\c!n=2, - \c!offset=\v!overlay, \c!frame=\v!off]

\newbox\b_page_columns_span \let\page_mul_postprocess_spanbox\gobbleoneargument ---