LaTeX Beamer callouts

beamer_fukidashi.tex

\documentclass[dvipdfmx]{beamer}

\usepackage{tikz}
\usetikzlibrary{shapes.callouts,tikzmark,calc}
% Usage: \COLabel{name#1}{text#2}
% e.g.:  \COLabel{psi1}{$\psi_1$}
\newcommand{\COLabel}[2]{%
	\tikz[%
		remember picture,%
		baseline=(#1.base),%
		every node/.style={inner sep=0,outer sep=0}%
	]{%
		\node (#1){#2};%
	}}
% Usage: \CO<page#1>{target name#2}{++(x,y)#3}[opt#4]{text#5}
% e.g.:  \CO<2>{psi1}{++(-4,1.5)}[text width=3cm]{hogehoge fugafuga piyopiyo}
\NewDocumentCommand\CO{d<> m m O{} m}{%
	\begin{tikzpicture}[remember picture, overlay]
		\IfValueTF{#1}{\path<#1>}{\path} (#2.center) #3 node[%
			anchor=center,%
			rectangle callout,%
			fill=red!50,%
			callout absolute pointer={(#2.mid)},%
			font=\bfseries\footnotesize,
			rounded corners,
			#4
		]{#5};
	\end{tikzpicture}}

\begin{document}
\begin{frame}\frametitle{}
	\begin{center}
		\COLabel{hogel}{}\COLabel{hoge}{ほげほげ}\COLabel{hoger}{}
	\end{center}
	\CO{hogel}{++(-1,-1)}{left}
	\CO{hoge}{++(0,-1)}{middle}
	\CO{hoger}{++(1,-1)}{right}
\end{frame}

\end{document}