beamer > beamercolorbox > Text with Shadow or Glow

Question

• This is a "fun" project.
• I want to create a beamer presentation with a fancy title frame.
• The goal is to have a black title frame with "bight colorful" text on it that looks like neon text (glowing).
• It's a bit inspired by the intro of the TV show "Stranger Things".
• Ideally, I want to stick to beamer's beamercolorbox approach to build the title frame template.
• I found some (partly older) related questions but I was hoping that by now there is a simple solution available. There seems to be solutions available to generate this effect for boxes but not for text.
• Question: Any idea how to generate a "neon glow" for normal text on the title frame with tikz and friends?

---

\documentclass{beamer}
\usepackage{tikz}
% Potentially Useful Libraries
\usetikzlibrary{
    shadows.blur, % "pgf-blur" package
    }
% Title of Presentation
\title{Presentation Title}
% Definition of Title Frame
\setbeamertemplate{title page}
    {
    \begin{beamercolorbox}[center]{title}
        \usebeamerfont{title}\inserttitle
    \end{beamercolorbox}
    }
% Definition of Font Color of Title (Used in "\setbeamertemplate{title page}")

\setbeamercolor{title}{fg=pink}
% Related
% https://tex.stackexchange.com/questions/315989
% https://tex.stackexchange.com/questions/401032
% https://tex.stackexchange.com/questions/493401
% https://tex.stackexchange.com/questions/315989
% https://tex.stackexchange.com/questions/446841
\begin{document}
% Title Frame
\setbeamercolor{background canvas}{bg=black}
\begin{frame}
\maketitle
\end{frame}
\setbeamercolor{background canvas}{bg=}
% Normal Frame
\begin{frame}{Frame Title}
Text
\end{frame}
\end{document}

Related

• Adding shadow to font in beamer title
• Can Gaussian (or similar) blur be applied to Tikz text?
• How to apply the "glow" effect to a rectangle with tcolorbox?
• Adding shadow to font in beamer title
• overlapping shadow with tikz

Answer 1

This is not a complete answer but a simple trick to get something that resembles the neon text. One can use the contour package and superimpose several contours of different widths and low opacities to get such an effect. As pointed out here, transparency groups are important when combining contour with nontrivial opacities.

\documentclass[tikz,border=3mm]{standalone}
\usepackage{contour}
\begin{document}
\begin{tikzpicture}
\fill (-1,-1) rectangle (1,1);
 \foreach \xyz in {0.05,0.1,...,1.5}
 {\begin{scope}[transparency group,opacity=.05]
 \contourlength{\xyz pt}
 \path[font=\Huge]
 node{\contour{red}{Test}};
 \end{scope}};
\end{tikzpicture}
\end{document}

Some quick and simpleminded implementation in beamer (i.e. there are almost certainly better ways).

\documentclass{beamer}
\usepackage{tikz}
\usepackage{contour}
\title{Presentation Title}
% Definition of Title Frame
\setbeamertemplate{title page}
    {
    \begin{beamercolorbox}[center]{title}
    \begin{tikzpicture}
\fill (-1,-1) rectangle (1,1);
 \foreach \xyz in {0.05,0.1,...,1.5}
 {\begin{scope}[transparency group,opacity=.05]
 \contourlength{\xyz pt}
 \path
 node{\contour{red}{\usebeamerfont{title}\Huge\inserttitle}};
 \end{scope}};
\end{tikzpicture}
    \end{beamercolorbox}
    }
% Definition of Font Color of Title (Used in "\setbeamertemplate{title page}")

\setbeamercolor{title}{fg=black}
\begin{document}
% Title Frame
\setbeamercolor{background canvas}{bg=black}
\begin{frame}
\maketitle
\end{frame}
\setbeamercolor{background canvas}{bg=}
% Normal Frame
\begin{frame}{Frame Title}
Text
\end{frame}
\end{document}