The design of a two-page spread for chapter openings involves a shaded background which runs across both pages. I have constructed this with:
\documentclass{article}
\usepackage[a3paper,landscape,margin=0pt,nohead,nofoot]{geometry}
\pagestyle{empty}
\usepackage[svgnames]{xcolor}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[remember picture,overlay]
\node [shading = axis,
rectangle,
left color=Red,
right color=Red,
middle color=Blue,
shading angle=45,
anchor=north,
minimum width=\paperwidth,
minimum height=\paperheight] (box) at (current page.north){};
\end{tikzpicture}
\end{document}
I need to use this in two halves, one for the left-hand page and one for the right-hand page (both will get other material superimposed).
Can I use this overlay twice, once for the left-hand half and once for the right? Perhaps by clipping or viewporting differently for each one? I can't see from the TikZ manual anything to do that (clip seems to do something completely different).
Or is there a way to construct two separate overlays which will join up to resemble thw full double-page spread? (My trig isn't good enough to work that out).
