> Am 30.04.2020 um 02:05 schrieb jbf <roma83...@gmail.com>:
>
> Hi list,
>
> With 99% of work complete on a book, including single page images, I now find
> myself confronted with a final problem: how to run one image across facing
> pages or in other words, one image (plus its caption) across a two-page
> spread, such that there is no gap.
You need to use \clip and calculate the sections.
Thangalin already gave you an example. Here’s a convoluted one that I use:
% full double page image
% usage:
% \startpostponing[pagenumber]
% \doublepagefig[reference][left/right/width/height*]{caption}{filename}
% \stoppostponing
% * lw,lh,rw,rh - place as left/right page, adapt image to width/height
% default is lw
% postponing is important, otherwise the page numbering gets wrong
\newdimen\Bleed
\newdimen\maxWidth
\newdimen\maxHeight
\newdimen\doubleWidth
\newdimen\topOffset
\newdimen\bottomOffset
\Bleed=3mm
\setupbleeding[offset=\Bleed]
\maxWidth=\dimexpr\paperwidth + \Bleed\relax
\maxHeight=\dimexpr\paperheight + 2\Bleed\relax
\doubleWidth=\dimexpr2\maxWidth\relax
\topOffset=\dimexpr\topspace + \headerheight + \Bleed\relax
\bottomOffset=\dimexpr\bottomheight + \footerheight + \Bleed\relax
\definelayer[bgpicleft][x=-\Bleed,y=-\Bleed,width=\maxWidth,height=\maxHeight]
% inkl. Beschnitt
\definelayer[bgpicright][x=0mm,y=-\Bleed,width=\maxWidth,height=\maxHeight] %
inkl. Beschnitt
\definemakeup[fullpage][
page=no,
doublesided=no,
headerstate=empty,
footerstate=empty,
pagestate=start,
]
\def\doublepagefig{\dodoubleempty\doDoublePagefig}
\def\doDoublePagefig[#1][#2]#3#4{
\startfullpagemakeup
\setlayer[bgpicleft]{\textreference[#1]{}%
\clip[
hoffset=0mm, voffset=0mm,
width=\maxWidth,
height=\maxHeight,
]{%
\doifinstringelse{h}{#2}{%
\externalfigure[#4][height=\maxHeight]%
}{%
\externalfigure[#4][width=\doubleWidth]%
}%
}%
}
% set caption into footer (left page)
\doiftext{#3}{\doifinstring{l}{#2}{%
\setlayer[bgpicleft][
x=\backspace,
y=\dimexpr\makeupheight + \footerheight\relax,
]{%
\doifmodeelse{blackcaption}{%
\tfx\vbox{#3}%
}{%
\inframed[
frame=off,background=shadow,
foregroundcolor=captioncolor,]{%
\bfx{#3}%\vbox{#3}%
}%
}%
}%
}}
% debugging information
\setlayer[bgpicleft][x=0mm,y=-\Bleed]{%
\color[debugcolor]{~\tt\bfx #1 / #2 / #4}
}
\stopfullpagemakeup
\startfullpagemakeup
\setlayer[bgpicright]{%
\clip[
hoffset=\maxWidth,
voffset=0mm,
width=\maxWidth,
height=\maxHeight,
]{%
\doifinstringelse{h}{#2}{%
\externalfigure[#4][height=\maxHeight]%
}{%
\externalfigure[#4][width=\doubleWidth]%
}%
}%
}
% set caption into footer (right page)
\doiftext{#3}{\doifinstring{r}{#2}{%
\setlayer[bgpicright][
x=\backspace,
y=\dimexpr\makeupheight + \footerheight\relax,
]{%
\doifmodeelse{blackcaption}{%
\tfx\vbox{#3}%
}{%
\inframed[
frame=off,background=shadow,foregroundcolor=captioncolor]{%
\bfx{#3}%\vbox{#3}%
}%
}%
}%
}}%
% debugging information
\setlayer[bgpicright][x=0mm,y=-\Bleed]{%
\color[captioncolor]{~\tt\bfx #1 / #2 / #4}
}
\stopfullpagemakeup
} % doublepagefig
You can see the outcome here:
https://www.dreiviertelhaus.de/architekturfuehrer/hicog/
Have fun,
Hraban
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