I provide \earmark
in the manner requested.
To elaborate, I use the atbegshi
package to allow things to be added at page shipout. I create the \atxy{<x>}{<y>}{<content>}
macro for placing these shipout items in the foreground at the specified (x,y) location. Finally, I define \earmark
to place a transparent triangle at (x,y) = (0pt
, \paperheight
) using \atxy
.
I apologize that my brute force tikz
transparent triangle is a result of my poor tikz
knowledge.
\documentclass{beamer}
\usepackage{atbegshi}
\usepackage{lipsum,tikz}
\def\PageTopMargin{1in}
\def\PageLeftMargin{1in}
\newcommand\atxy[3]{%
\AtBeginShipoutNext{\AtBeginShipoutAddToBoxForeground{%
\smash{\hspace*{\dimexpr-\PageLeftMargin-\hoffset+#1\relax}%
\raisebox{\dimexpr\PageTopMargin+\voffset-#2\relax}{#3}}}}}
\def\earmark{%
\atxy{0pt}{\paperheight}{\begin{tikzpicture}
\node[outer sep=0.46in] (earmark) {};
\draw[blue!40, fill, opacity=0.25] (earmark.south west) -- (earmark.south east) --
(earmark.north west)-- (earmark.south west);
\end{tikzpicture}}
}
\begin{document}
\begin{frame}{title of the slide}
\earmark
\lipsum[3]
blah blah\par
blah blah\par
And here we test opacity
\end{frame}
\begin{frame}{next slide}
There is no earmark here
\end{frame}
\end{document}
