\pdfstringdef turns accented characters into octal escape sequence

Question

The Question : How to make a glowing text?

@'Symbol 1', interesting, I encapsulated your script into a new command (named '\glow') so I could highlight text just like with '\hl{}'. However the result of '\glow{This is a \hl{test}}' was not satisfactory due to the fact that the yellow box was rewritten multiple time above the glowing effect, hiding it.

So I tried to modify your solution, print the original string first (say with '\hl{}'), use \pdfstringdef to remove the formatting and get a clean/plain string for the glowing string, then display it one last time above to get a clean text.

Yet \pdfstringdef turns accented characters into octal sequences as seen here :

How to strip a string of all formatting

Here's a little tweaked version with transparency to "respect" highlight or other background effects. Yet the problem remains for accented characters or even parenthesis and alike :

\documentclass{article}
\usepackage{tikz}               % Graphique
\usepackage{transparent}        % Transparence
%\usepackage[outline]{contour}  % Contour
\usepackage{xcolor}             % Couleurs par nom
\usepackage{soul}               % \hl{}
\usepackage{hyperref}           % \pdfstringdef
% =============================================================================
\makeatletter   % Autorise la modification des macros système
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
% /!\ UTILISATION DE 'PDFSTRINGDEF' POUR 'NETTOYER' LE TEXTE
\newcommand{\glow}[2]{
        % Début liste de 'nettoyage' (rajouter les commandes à 'nettoyer')
        \pdfstringdefDisableCommands{\def\hl{}} % Nettoyage de '\hl{#1}'
        % Fin liste de 'nettoyage'
        \pdfstringdef\plainstr{#2}  % Extraction chaine 'nettoyée'
%       #2%i                        % Texte avec mise en forme (fond) NOK
        \leavevmode                 % Mode horizontal (pas de passage à la ligne implicite)
        \pgfsys@beginscope          % = pdfliteral{q}
            \rlap{#2}%i             % Texte avec mise en forme (fond) 1x
            \pgfsetroundjoin        % = pdfliteral{1 j}
            \pgfsetroundcap         % = pdfliteral{1 J}
            \pdfliteral{1 Tr}%i     % no pgf alternative
            \foreach\ind in {10, ..., 1}{%i
                    \pgfmathsetmacro\per{(11-\ind)*5}%i
\iffalse
                        % Couleur décroissante
                        \color{#1!\per}%
\else
                        % Transparence cumulée
                        \color{#1}%
                        \transparent{0.1}%              % 10% max
\fi
\iftrue
                        % Contour 'léger'
                        \pgfsetlinewidth{\ind/2}        % light
\else
                        % Contour 'épais'
                        \pgfsetlinewidth{(\ind/2)+1}    % heavy
\fi
%                   \rlap{#2}%i                         % x fois COULEUR avec mise en forme NOK
                    \rlap{\plainstr}%i                  % x fois COULEUR sans mise en forme
                }%i
        \pgfsys@endscope            % = pdfliteral{Q}
        \plainstr                   % Texte sans mise en forme (dessus) NOIR
%       #2%i                        % Texte avec mise en forme (dessus) NOIR
    }
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
\makeatother    % Bloque la modification des macros système
% =============================================================================
\begin{document}
COMPILE AT LEAST TWICE !!!
This is a test.
This is another \hl{test}.
\glow{green}{This one is supposed to glow without highlight.}
\glow{cyan}{This one is also supposed to \hl{glow} preserving the highlight.}
pdfstringdefDisableCommands and pdfstringdef removes the formatting.
Then I overwrite the glowing string with a clean black string without hl{}.
\glow{orange}{But accented characters are a hell to deal with.}
\glow{red}{Bùt àccéntèd charaçters are a hell to deal wïth.}
Even parenthesis gets "destroyed" in the process...
\end{document}

Btw I'm trying to mimic Word's text glowing function :

Any solution ?

PS : I cannot add the tags 'latex', or 'glow' or 'pdfstringdef' unless I have 300 "reputation"

EDIT : with the solution provided, which work in general (accented characters are rendered correctly) I get a "feedback" effect now. I should investigate. "Not that elementary, my dear Watson".

Answer 1

Try with \text_purify:n (requires a rather current text system!)

\documentclass{article}
\usepackage{tikz}               % Graphique
\usepackage{transparent}        % Transparence
%\usepackage[outline]{contour}  % Contour
\usepackage{xcolor}             % Couleurs par nom
\usepackage{soul}               % \hl{}
\usepackage{hyperref}           % \pdfstringdef
% =============================================================================
\makeatletter   % Autorise la modification des macros système
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
\ExplSyntaxOn
\cs_set_eq:NN\textpurify\text_purify:n
\ExplSyntaxOff
% /!\ UTILISATION DE 'PDFSTRINGDEF' POUR 'NETTOYER' LE TEXTE
\newcommand{\glow}[2]{
        % Début liste de 'nettoyage' (rajouter les commandes à 'nettoyer')
        %\pdfstringdefDisableCommands{\def\hl{}} % Nettoyage de '\hl{#1}'
        % Fin liste de 'nettoyage'
        \edef\plainstr{\textpurify{#2}}  % Extraction chaine 'nettoyée'
%       #2%i                        % Texte avec mise en forme (fond) NOK
        \leavevmode                 % Mode horizontal (pas de passage à la ligne implicite)
        \pgfsys@beginscope          % = pdfliteral{q}
            \rlap{#2}%i             % Texte avec mise en forme (fond) 1x
            \pgfsetroundjoin        % = pdfliteral{1 j}
            \pgfsetroundcap         % = pdfliteral{1 J}
            \pdfliteral{1 Tr}%i     % no pgf alternative
            \foreach\ind in {10, ..., 1}{%i
                    \pgfmathsetmacro\per{(11-\ind)*5}%i
\iffalse
                        % Couleur décroissante
                        \color{#1!\per}%
\else
                        % Transparence cumulée
                        \color{#1}%
                        \transparent{0.1}%              % 10% max
\fi
\iftrue
                        % Contour 'léger'
                        \pgfsetlinewidth{\ind/2}        % light
\else
                        % Contour 'épais'
                        \pgfsetlinewidth{(\ind/2)+1}    % heavy
\fi
%                   \rlap{#2}%i                         % x fois COULEUR avec mise en forme NOK
                    \rlap{\plainstr}%i                  % x fois COULEUR sans mise en forme
                }%i
        \pgfsys@endscope            % = pdfliteral{Q}
        \plainstr                   % Texte sans mise en forme (dessus) NOIR
%       #2%i                        % Texte avec mise en forme (dessus) NOIR
    }
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
\makeatother    % Bloque la modification des macros système
% =============================================================================
\begin{document}
COMPILE AT LEAST TWICE !!!
This is a test.
This is another \hl{test}.
\glow{green}{This one is supposed to glow without highlight.}
\glow{cyan}{This one is also supposed to \hl{glow} preserving the highlight.}
pdfstringdefDisableCommands and pdfstringdef removes the formatting.
Then I overwrite the glowing string with a clean black string without hl{}.
\glow{orange}{But accented characters are a hell to deal with.}
\glow{red}{Bùt àccéntèd charaçters are a hell to deal wïth.}
Even parenthesis gets "destroyed" in the process...
\end{document}

Answer 2

Just a quick note about 'xspace', despite I know it's a "necessary evil" in many cases, just like in my own. The project name is embedded in a macro so that the changing the project name is straightforward (replace the macro content and voilà). But being a macro, the spaces following gets nuked into oblivion. While not a problem before a punctuation, it gets confusing inside a sentence when two adjacent words gets glued together without reason (even though we can always find a valid reason somehow, like planetary alignment and so on).

Anyway, I created a little MWE that demonstrate it really was the stripping of the 'xspace' that caused the "strange feedback effect". And now, another giant leap forward for mankind...

(Btw, I also tweaked the color/transparency settings and I think I nailed it, looks a lot more like Word's glowing, and no more color bleeding : "Yeah Baby, Yeah!")

\documentclass{article}
\usepackage{tikz}               % Graphique
\usepackage{transparent}        % Transparence
\usepackage{xcolor}             % Couleurs par nom
\usepackage{soul}               % \hl{}
\usepackage{xspace}             % Gestion des espaces
\def\test{\hl{test}\xspace}     % <<--- THE MACRO !!!
% =============================================================================
\makeatletter   % Autorise la modification des macros système
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
\ExplSyntaxOn
\cs_set_eq:NN\textpurify\text_purify:n
\ExplSyntaxOff
% /!\ UTILISATION DE 'TEXT_PURIFY' POUR 'NETTOYER' LE TEXTE
\newcommand{\glow}[2]{
        \edef\plainstr{\textpurify{#2}}  % Extraction chaine 'nettoyée'
%       #2%i                        % Texte AVEC mise en forme (fond) (NOK)
        \leavevmode                 % Mode horizontal (pas de passage à la ligne implicite)
        \pgfsys@beginscope          % = pdfliteral{q}
            \rlap{#2}%i             % Texte AVEC mise en forme (fond) 1x
            \pgfsetroundjoin        % = pdfliteral{1 j}
            \pgfsetroundcap         % = pdfliteral{1 J}
            \pdfliteral{1 Tr}%i     % no pgf alternative
            \foreach\ind in {10, ..., 1}{%i
                    \pgfmathsetmacro\per{(11-\ind)*5}%i
                    \color{#1!\per}%                % Couleur décroissante
                    \transparent{0.2}%              % Transparence cumulée
\iftrue
                    \pgfsetlinewidth{\ind/2}        % Contour 'léger'
\else
                    \pgfsetlinewidth{(\ind/2)+1}    % Contour 'épais'
\fi
%                   \rlap{#2}%i                     % x fois COULEUR AVEC mise en forme (NOK)
                    \rlap{\plainstr}%i              % x fois COULEUR sans mise en forme
                }%i
        \pgfsys@endscope            % = pdfliteral{Q}
%       #2%i                        % Texte AVEC mise en forme (dessus) NOIR
        \plainstr                   % Texte sans mise en forme (dessus) NOIR
    }
% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
\makeatother    % Bloque la modification des macros système
% =============================================================================
\begin{document}
COMPILE AT LEAST TWICE !!!
This is a \hl{test}.
This is another \test with a macro instead.
\glow{green}{This test is sùpposed to glow without highlight.}
\glow{cyan}{This \hl{test} is sûpposed to glow preserving the highlight.}
\glow{cyan}{This \test macro featüres a xspace that is context dependant.}
However text_purify seems to be overzealous and "purify" it.
\end{document}