# Transparent background spanning several tikzpictures

I am trying to display a "forbidden sign" in the background of two tikzpictures (much like some kind of watermark). However, in the following MWE the "forbidden sign" is cut-off at some seemingly arbitrary horizontal line.

\documentclass{scrartcl}

\usepackage{tikz}
\usetikzlibrary{backgrounds,shapes}

\begin{document}
\noindent
\begin{tikzpicture}
\draw[green] (0.0, -5.0) rectangle (10.0, 0.0);
\end{tikzpicture}\\
\begin{tikzpicture}
\draw[blue] (0.0, -5.0) rectangle (10.0, 0.0);
\begin{pgfonlayer}{background}
\begin{scope}[opacity=0.5,transparency group,overlay]
\draw node[forbidden sign,
minimum size=5cm,
line width=2ex,
draw=red,
fill=white] at (5.0,0.0) {Test};
\end{scope}
\end{pgfonlayer}
\end{tikzpicture}
\end{document}


Do you have any idea how I can fix this behaviour?

-
You need to remove overlay – Alain Matthes Jun 19 '12 at 16:32
@Altermundus: I think it is not sufficient in this case simply removing overlay. That was my first attempt, but then the pictures were not more near. – Claudio Fiandrino Jun 19 '12 at 16:36
When I remove overlay, the "forbidden sign" does not span the first tikzpicture. – Aton Jun 19 '12 at 16:41
I would like to say : remove from the node option but I don't know exactly what result is desired. – Alain Matthes Jun 19 '12 at 16:47
Why don't you use directly a watermark as given in the manual? It's much more simpler. – percusse Jun 19 '12 at 16:52
show 1 more comment

It seems difficult to use overlay with transparency group

\documentclass{scrartcl}
\usepackage{tikz}
\usetikzlibrary{backgrounds,shapes}
\pgfdeclarelayer{myback}
\pgfsetlayers{myback,main}
\newsavebox{\mybox}
\begin{document}
\parindent=0pt

\savebox{\mybox}{%
\begin{tikzpicture}[transparency group,opacity=.5]
\node[forbidden sign,
minimum size=5cm,
line width=2ex,
draw=red,
fill=white]  {};
\end{tikzpicture}}

\begin{tikzpicture}
\draw[green] (0.0, -5.0) rectangle (10.0, 0.0);
\end{tikzpicture}\\ \baselineskip=0pt
\begin{tikzpicture}[remember picture,overlay]
\draw[blue] (0.0, -5.0) rectangle (10.0, 0.0);
\begin{pgfonlayer}{myback}
\node[inner sep=0pt] (s) at (5,0){\usebox\mybox};
\end{pgfonlayer}
\end{tikzpicture}

\end{document}


-
 but there is other ways to get this. – Alain Matthes Jun 19 '12 at 16:50 That is almost the result I would like to achieve. However I would like the two intersections of the line and the circle to have the same color. That is why I tried using "transparency group" in the first place. See pgfmanual, section 20.4 "Transparency Groups". – Aton Jun 19 '12 at 16:54 A list of requests at the beginning of the first question is a better way to get a good answer :) Do you need two pictures ? – Alain Matthes Jun 19 '12 at 16:59 Thanks for your answer! That seems to work. You mentioned that there are other ways to get this''. Could you elaborate on that? For clarification: in general I would like to be able to place watermark-like tikzpictures anywhere on the page relative to an existing-node. Btw, I searched the pgfmanual for 'watermark' but did not find a solution. – Aton Jun 19 '12 at 18:58 There are some packages to place a picture on a page (eso-pic,watermark etc.) Here the problem seems to be a conflict between remember picture, overlay and transparency group. Finally it's difficult to avoid this problem because you need remember picture and overlay to place a picture in a page. Perhaps you need to wait another solution. – Alain Matthes Jun 19 '12 at 19:24