Re: placefigure feature request ?

[Hans Hagen <pragma@wxs.nl>]

Sanjoy Mahajan wrote:
>>> It would be nice if placefigure can be able to detect if the best
>>> place is the top or the bottom of the page accordingly to its call,
>>>       
>
> A related point, which I didn't fiugre out how for my own TeX
> figure-placement macros, is correct sequential numbering when some
> figures are at the top of the page.  Some pseudocode on one page:
>
> =============== snip ===================
> \ref{figure:narrow} is a narrow figure.
>
> \figuremacro{figure:narrow}{narrowfig.1}{A narrow figure.}
>
> \ref{figure:wide} is a wide figure.
>
> \figuremacro{figure:wide}{widefig.1}{A wide figure}
> =============== snip ===================
>
> Here \figuremacro figures out (sorry) that narrow figures go in the
> margin and wide figures go at the top of the page.  But the page will
> look funny: The narrow figure will be numbered, say, Figure 10, and
> the wide figure will be Figure 11, but Figure 11 will appear before
> Figure 10 on the page.  Which is disconcerting to the reader.  
>   
this 'choose between locations' feature is kind of present but only with 
'here' as fallback but it's trivial to make that configurable:

% first a new key

\startconstants            dutch                     english
                           german                    czech
                           italian                   romanian
                           french

                 fallback: terugval                  fallback
                           fallback                  fallback
                           fallback                  fallback
                           fallback
\stopconstants

% use that key

\long\def\dofloat#1#2#3#4%
  {\dosetfloatbox{#1}{#2}{#3}{#4}%
   \doifelsevaluenothing{\??fl#4\c!criterium}
     {\dogetfloatbox{#1}\empty}
     {\ifdim\wd\floatbox>\getvalue{\??fl#4\c!criterium}\relax
        \postcenterfloatbox{\wd\floatbox}% else we get left aligned
        %dogetfloatbox{#1}\v!here        % see details/pascal
        
\dogetfloatbox{#1}{\executeifdefined{\??fl#4\c!fallback}\v!here}% PATCHED
      \else
        \dogetfloatbox{#1}\empty
      \fi}}

% pass the new location (will be done differently, hack

\def\dogetfloatbox#1#2%
  {\ifvisible
     \doifelsenothing{#2}
       {\getfromcommalist[#1][1]%
        \@EA\beforesplitstring\commalistelement\at:\to\floatmethod
        \@EA\aftersplitstring \commalistelement\at:\to\floatcolumn
        \@EA\aftersplitstring \floatcolumn\at*\to\floatrow
        \@EA\beforesplitstring\floatcolumn\at*\to\floatcolumn
        % todo: nog algemeen otr
        \ifx\OTRSETsetpreferedcolumnslot\undefined\else
          \OTRSETsetpreferedcolumnslot\floatcolumn\floatrow
        \fi}
       {\let\floatcolumn\empty
        \let\floatrow\empty
        \edef\floatmethod{#2}}%
     \doifundefined{\string\floatmethod\floatmethod}
       {\let\floatmethod\v!here}%
     \getvalue{\string\floatmethod\floatmethod}[\floatmethod,#1]% PATCHED
   \fi}

\setupfloats[numbering=nocheck]

% we use the marginwidth as criterium

\setupfloat[figure][criterium=\marginwidth,fallback=bottom]

\starttext

\placefigure[bottom]{}{} \input tufte
\placefigure[left]{}{} \input tufte
\placefigure[left]{}{\framed[width=.8\marginwidth]{}} \input tufte

\stoptext

(we needed that feature a  couple of years ago in a project -)

Hans

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                                          Hans Hagen | PRAGMA ADE
              Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
                                             | www.pragma-pod.nl
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