From mboxrd@z Thu Jan  1 00:00:00 1970
X-Msuck: nntp://news.gmane.io/gmane.comp.tex.context/107450
Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail
From: Rik Kabel <ConTeXt@rik.users.panix.com>
Newsgroups: gmane.comp.tex.context
Subject: Re: Getting width of text to be typeset
Date: Fri, 22 May 2020 19:49:34 -0400
Message-ID: <357d26e1-2571-b30c-2eb6-c787ed3bbf18@rik.users.panix.com>
References: <1217e4fe7a813a0e714d342b9efec0c4@vivaldi.net>
 <e7ebbe94-0dbf-5113-8dc2-9af6cc6a8d82@xs4all.nl>
 <639ff2c9-65f6-b818-1d8f-9249331a9b8a@xs4all.nl>
Reply-To: mailing list for ConTeXt users <ntg-context@ntg.nl>
Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="===============0206756930610573056=="
Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202";
	logging-data="63619"; mail-complaints-to="usenet@ciao.gmane.io"
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Firefox/68.0 Thunderbird/68.8.0
To: ntg-context@ntg.nl
Original-X-From: ntg-context-bounces@ntg.nl Sat May 23 01:50:01 2020
Return-path: <ntg-context-bounces@ntg.nl>
Envelope-to: gctc-ntg-context-518@m.gmane-mx.org
Original-Received: from zapf.boekplan.nl ([5.39.185.232] helo=zapf.ntg.nl)
	by ciao.gmane.io with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <ntg-context-bounces@ntg.nl>)
	id 1jcHQP-000GQZ-5z
	for gctc-ntg-context-518@m.gmane-mx.org; Sat, 23 May 2020 01:50:01 +0200
Original-Received: from localhost (localhost [127.0.0.1])
	by zapf.ntg.nl (Postfix) with ESMTP id BA00B184422;
	Sat, 23 May 2020 01:49:42 +0200 (CEST)
X-Virus-Scanned: Debian amavisd-new at zapf.boekplan.nl
Original-Received: from zapf.ntg.nl ([127.0.0.1])
	by localhost (zapf.ntg.nl [127.0.0.1]) (amavisd-new, port 10024)
	with ESMTP id 4DspAa41ELHo; Sat, 23 May 2020 01:49:40 +0200 (CEST)
Original-Received: from zapf.ntg.nl (localhost [127.0.0.1])
	by zapf.ntg.nl (Postfix) with ESMTP id 6877B184428;
	Sat, 23 May 2020 01:49:40 +0200 (CEST)
Original-Received: from localhost (localhost [127.0.0.1])
 by zapf.ntg.nl (Postfix) with ESMTP id C8E901843FC
 for <ntg-context@ntg.nl>; Sat, 23 May 2020 01:49:38 +0200 (CEST)
X-Virus-Scanned: Debian amavisd-new at zapf.boekplan.nl
Original-Received: from zapf.ntg.nl ([127.0.0.1])
 by localhost (zapf.ntg.nl [127.0.0.1]) (amavisd-new, port 10024)
 with ESMTP id TgzPnNJby3qU for <ntg-context@ntg.nl>;
 Sat, 23 May 2020 01:49:37 +0200 (CEST)
Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=166.84.1.89;
 helo=mailbackend.panix.com; envelope-from=context@rik.users.panix.com;
 receiver=<UNKNOWN> 
Original-Received: from mailbackend.panix.com (mailbackend.panix.com [166.84.1.89])
 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits))
 (No client certificate requested)
 by zapf.ntg.nl (Postfix) with ESMTPS id 4A2B9183EC0
 for <ntg-context@ntg.nl>; Sat, 23 May 2020 01:49:37 +0200 (CEST)
Original-Received: from [192.168.201.21] (cpe-72-228-11-252.nycap.res.rr.com
 [72.228.11.252])
 by mailbackend.panix.com (Postfix) with ESMTPSA id 49TNWM2k1JzsXs
 for <ntg-context@ntg.nl>; Fri, 22 May 2020 19:49:35 -0400 (EDT)
In-Reply-To: <639ff2c9-65f6-b818-1d8f-9249331a9b8a@xs4all.nl>
Content-Language: en-US
X-BeenThere: ntg-context@ntg.nl
X-Mailman-Version: 2.1.26
Precedence: list
List-Id: mailing list for ConTeXt users <ntg-context.ntg.nl>
List-Unsubscribe: <https://mailman.ntg.nl/mailman/options/ntg-context>,
 <mailto:ntg-context-request@ntg.nl?subject=unsubscribe>
List-Archive: <http://mailman.ntg.nl/pipermail/ntg-context/>
List-Post: <mailto:ntg-context@ntg.nl>
List-Help: <mailto:ntg-context-request@ntg.nl?subject=help>
List-Subscribe: <https://mailman.ntg.nl/mailman/listinfo/ntg-context>,
 <mailto:ntg-context-request@ntg.nl?subject=subscribe>
Errors-To: ntg-context-bounces@ntg.nl
Original-Sender: "ntg-context" <ntg-context-bounces@ntg.nl>
Xref: news.gmane.io gmane.comp.tex.context:107450
Archived-At: <http://permalink.gmane.org/gmane.comp.tex.context/107450>

This is a multi-part message in MIME format.
--===============0206756930610573056==
Content-Type: multipart/alternative;
 boundary="------------B81E20CA6A18F246D3D50780"
Content-Language: en-US

This is a multi-part message in MIME format.
--------------B81E20CA6A18F246D3D50780
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit


On 5/22/2020 18:18, Hans Hagen wrote:
> On 5/23/2020 12:03 AM, Hans Hagen wrote:
>> On 5/22/2020 11:22 AM, context@vivaldi.net wrote:
>>> Hello,
>>>
>>> is it possible to get somehow the width of the "material" (box?) of 
>>> the current line which is "ready" to be typeset?
>>>
>>> See the case:
>>>
>>> ----
>>> \starttext
>>>
>>>    some text
>>>
>>>    pqrs % Here I need to get width (or content) of the text from the 
>>> begin of the current line,
>>>         % i.e. width of the text "pqrs".
>>>         % (Depending of the width I will decide what to do later.)
>>>
>>> \stoptext
>>> ----
>>>
>>> I am too laical to know how to "inject" TeX workflow or whether to 
>>> access LuaTeX internals (nodes?) to get the desired information.
>>>
>>> - Is it possible somehow?
>> Too easy ...
>>
>> \startluacode
>>      function document.whatever()
>>          context(nodes.hpack(tex.getnest().head.next).width)
>>      end
>> \stopluacode
>>
>> \unexpanded\def\widthuptohere{\dimexpr\ctxlua{document.whatever()}sp\relax} 
>>
>>
>> \starttext
>>
>>      \dorecurse {10} {
>>          snippet #1\scratchdimen\widthuptohere\ has 
>> \the\scratchdimen\ width\par
>>      }
>>
>> \stoptext
>>
>> but still you have to wikify it ... maybe i'll make it a low level 
>> helper (but than you also need to wikify that because i have no clue 
>> where to explain it)
> Actually, one needs to flush a bit
>
> \startluacode
>     function document.whatever()
>         local h = nodes.hpack(tex.getnest().head.next)
>         local w = h.width
>         h.list = nil
>         nodes.free(h)
>         context(w)
>     end
> \stopluacode
>
> \unexpanded\def\widthuptohere{\dimexpr\ctxlua{document.whatever()}sp\relax} 
>
>
> \starttext
>
>     \dorecurse {10} {
>         snippet #1\scratchdimen\widthuptohere\ has \the\scratchdimen\ 
> width\par
>     }
>
> \stoptext
>
> not that it matters much, because it's unlikely that you leak more 
> than a dozen nodes in a run.
>
> Hans
>
If the OP simply wants the width of a string, one can use 
\setwidthof#1\to#2.

    \define\String{pqrs}
    \setwidthof{\String}\to\Wdth
    \String\ is \Wdth\ wide.

    \setwidthof{{\tfb\em\String}}\to\Wdth
    {\tfb\em\String} is \Wdth\ wide.

I do not know if that is different from the width of the same string 
unboxed from the paragraph. There may be some adjustments made in 
justification, expansion, and such that are not treated.

-- 
Rik


--------------B81E20CA6A18F246D3D50780
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: 8bit

<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body>
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 5/22/2020 18:18, Hans Hagen wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:639ff2c9-65f6-b818-1d8f-9249331a9b8a@xs4all.nl">On
      5/23/2020 12:03 AM, Hans Hagen wrote:
      <br>
      <blockquote type="cite">On 5/22/2020 11:22 AM, <a class="moz-txt-link-abbreviated" href="mailto:context@vivaldi.net">context@vivaldi.net</a>
        wrote:
        <br>
        <blockquote type="cite">Hello,
          <br>
          <br>
          is it possible to get somehow the width of the "material"
          (box?) of the current line which is "ready" to be typeset?
          <br>
          <br>
          See the case:
          <br>
          <br>
          ----
          <br>
          \starttext
          <br>
          <br>
             some text
          <br>
          <br>
             pqrs % Here I need to get width (or content) of the text
          from the begin of the current line,
          <br>
                  % i.e. width of the text "pqrs".
          <br>
                  % (Depending of the width I will decide what to do
          later.)
          <br>
          <br>
          \stoptext
          <br>
          ----
          <br>
          <br>
          I am too laical to know how to "inject" TeX workflow or
          whether to access LuaTeX internals (nodes?) to get the desired
          information.
          <br>
          <br>
          - Is it possible somehow?
          <br>
        </blockquote>
        Too easy ...
        <br>
        <br>
        \startluacode
        <br>
             function document.whatever()
        <br>
                 context(nodes.hpack(tex.getnest().head.next).width)
        <br>
             end
        <br>
        \stopluacode
        <br>
        <br>
\unexpanded\def\widthuptohere{\dimexpr\ctxlua{document.whatever()}sp\relax}
        <br>
        <br>
        \starttext
        <br>
        <br>
             \dorecurse {10} {
        <br>
                 snippet #1\scratchdimen\widthuptohere\ has
        \the\scratchdimen\ width\par
        <br>
             }
        <br>
        <br>
        \stoptext
        <br>
        <br>
        but still you have to wikify it ... maybe i'll make it a low
        level helper (but than you also need to wikify that because i
        have no clue where to explain it)
        <br>
      </blockquote>
      Actually, one needs to flush a bit
      <br>
      <br>
      \startluacode
      <br>
          function document.whatever()
      <br>
              local h = nodes.hpack(tex.getnest().head.next)
      <br>
              local w = h.width
      <br>
              h.list = nil
      <br>
              nodes.free(h)
      <br>
              context(w)
      <br>
          end
      <br>
      \stopluacode
      <br>
      <br>
\unexpanded\def\widthuptohere{\dimexpr\ctxlua{document.whatever()}sp\relax}
      <br>
      <br>
      \starttext
      <br>
      <br>
          \dorecurse {10} {
      <br>
              snippet #1\scratchdimen\widthuptohere\ has
      \the\scratchdimen\ width\par
      <br>
          }
      <br>
      <br>
      \stoptext
      <br>
      <br>
      not that it matters much, because it's unlikely that you leak more
      than a dozen nodes in a run.
      <br>
      <br>
      Hans
      <br>
      <br>
    </blockquote>
    <p>If the OP simply wants the width of a string, one can use <font
        size="+1"><tt>\setwidthof#1\to#2</tt></font>.</p>
    <blockquote><font size="+1"><tt>\define\String{pqrs}<br>
          \setwidthof{\String}\to\Wdth<br>
          \String\ is \Wdth\ wide.<br>
          <br>
          \setwidthof{{\tfb\em\String}}\to\Wdth<br>
          {\tfb\em\String} is \Wdth\ wide.<br>
        </tt><br>
      </font></blockquote>
    I do not know if that is different from the width of the same string
    unboxed from the paragraph. There may be some adjustments made in
    justification, expansion, and such that are not treated.<br>
    <br>
    -- <br>
    Rik<br>
    <br>
  </body>
</html>

--------------B81E20CA6A18F246D3D50780--

--===============0206756930610573056==
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: base64
Content-Disposition: inline
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--===============0206756930610573056==--