# [NTG-context] xpos.sty

Hans Hagen pragma at wxs.nl
Wed Aug 30 01:32:35 CEST 2006

Paul Jones wrote:
>
> Thank you again for very timely and great answers to my question
> yesterday.  I am finding that implementing things in Context is
> usually easier than I expect.  This is very nice.  Our company decided
> to switch to context from latex recently.  It seems to have been a
> very good decision.  Thanks for all the work you do to make context so
> fun to use.
>
> We have one last thing to get translated from latex to context.  David
> Kastrup wrote a bit of latex for us (included below) that magically
> writes out the absolute xy position of each paragraph and image to a
> log file for us.  We pass some extra information to the commands that
> get put in the log file for us, but in the end we mainly need a way to
> get the absolute xy coordinates of the bounding boxes for each
> paragraph, each section title, each image and each image caption.  Is
> there a way to get this information with context already? Or do I need
> to get a new module written?
i dunno about that code but context has support for positions for years now, in your case you probably need something

\starttext

\let\CurrentPos\empty

\def\StartPos#1%
{\pushmacro\CurrentPos
\edef\CurrentPos{mypos:#1}%
\dontleavehmode\bpos\CurrentPos
\ignorespaces}

\def\StopPos
{\removeunwantedspaces
\epos\CurrentPos
\popmacro\CurrentPos}

\def\BoxPos#1%
{\dowithnextbox{\hbox{\hpos{mypos:#1}{\box\nextbox}}}\vbox}

\StartPos{x}\input tufte \StopPos

\StartPos{y}\input zapf \StopPos

\placefigure
{}
{\BoxPos{q}{\framed[width=3cm,height=4cm]{}}}

\stoptext

in the *.tui/tuo file you can grep for mypos

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