Fw: A question about layers

[Marcin Borkowski <mbork@wmi.amu.edu.pl>]

And the second message accidentally sent to Hans:

Dnia 2011-07-14, czw o godzinie 16:29 +0200, Hans Hagen pisze:
> On 14-7-2011 4:25, Marcin Borkowski wrote:
> > OK,
> >
> > after a pm from Mojca concerning my previous question I decided to
> > look into the "layers" mechanism.
> >
> > It won't work for me - just nothing shows up.
> >
> > What am I doing wrong?
> >
> > Here's a minimal example:
> >
> > \starttext
> > \definelayer[title][x=105mm,y=20mm]
> > \setlayer[title]{This is the title.}
> > \stoptext
> >
> > (I'd also like to be able to "anchor" the title so that
> > (105mm,20mm) are the coordinates of the center, not the lower-left
> > corner etc.  How to do that?)
> 
> \flushlayer[title]
> 
> etc (some styles in the distributions have examples)

I think that the general problem is that I have a wrong conceptual model
of layers in ConTeXt.  You know, when I hear the word "layer", I have
some ideas about how it should/could/might work, and probably these
ideas are different than Hans'.  So I'm going to briefly describe my
idea (already modified by the answers) and please tell me what's wrong
with it.

So I imagine that \definelayer / \setuplayer defines a rectangular shape
on the page, possibly framed/colored/etc., which is going to appear on
all pages (default) or on selected ones.  The contents of layers are set
with \setlayer, (with some - mysterious for me - "setups" trickery if
they are going to change from page to page), and they are actually put
on the page by \setupbackgrounds.  (And I have no idea what \flushlayer
does in this conceptual framework.)  So layers are actually kind of
"beneath" ordinary page contents.

Some of these commands (which ones?) should moreover be placed before
\startext.

OK, so where am I right and where am I wrong now?


-- 
Marcin Borkowski
http://mbork.pl


-- 
Marcin Borkowski
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