Remove color of acronyms used in an equation

Question

I use the acronyms package to define mathematic symbols like this:

\begin{acronym}[long]
\acro{v}[$\vec{v}$]{View direction vector}
\end{acronym}

I do this with lots of others where it is faster to type \acs{<short>} instead of the long math mode expression.

When I use this, the hyperref package makes the output be formatted in a certain color. I like that for acronyms like GPS where I want the reader to see that the short version is clickable. For those I use a different list of acronyms similar to the one above.

But I don't want the mathematical expressions be colored in equations, because it disturbs readability if some are defined as acronyms and others are written manually.

My question is now: Can I make hyperref remove the color of the links from a specific list of acronyms? Or can I turn off the link coloring for math mode?

This is my first question here, I hope I made my problem clear :-)

---

Added example: (I'm using classicthesis and arsclassica which make the links colored but it should not matter where the colors come from)

\documentclass{scrreprt}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% REQUIRED FOR ARSCLASSICA
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage{subfig}
\usepackage[strict]{changepage}
\usepackage[parts,dottedtoc,eulerchapternumbers,subfig,beramono,pdfspacing] {classicthesis}
\usepackage{arsclassica}

% hyperref and acronym
\usepackage{hyperref}
\usepackage{acronym}

\begin{document}
    \chapter{Text}
    Some text where I want to have \ac{BRDF} as a visibly colored link and in 
    an equation would not want the symbol to be a colored link.

    \begin{equation}
        \acs{fBRDF} = \dots
    \end{equation}

    However it would be nice if it still was a link. It just should not have 
    any color.

    % Two acronym lists
    \chapter{List of Abbreviations}
    \begin{acronym}[GPS]
        \acro{BRDF}{Bidirectional Reflectance Distribution Function}
        \acro{RGB}{Red, Green, Blue}
    \end{acronym}

    \chapter{List of Symbols}
    \begin{acronym}[$f(\vec{l},\vec{v})$]
        \acro{fBRDF}[$f(\vec{l},\vec{v})$]{\acf{BRDF}}
    \end{acronym}

\end{document}

Answer 1

It's possible to set the link color inside of an environment temporarily to another value (other than specified before) and to restore it to the original one afterwards.

I used the xpatch package to append the color change code after the start of the equation environment (macro \equation) and to switch back after \endequation (which is \end{equation} effectively).

For better convenience I defined the commands \DefaultDocumentLinkColor and \DefaultDocumentEquationLinkColor to hold the color names.

However, the equation link is not recognizable as such using the normal text color.

\documentclass{scrreprt}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% REQUIRED FOR ARSCLASSICA
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage{subfig}
\usepackage[strict]{changepage}
\usepackage[parts,dottedtoc,eulerchapternumbers,subfig,beramono,pdfspacing]{classicthesis}
\usepackage{arsclassica}

% hyperref and acronym

\usepackage{xpatch}

\newcommand{\DocumentDefaultLinkColor}{blue}
\newcommand{\DocumentDefaultEquationLinkColor}{black}


\usepackage{hyperref}
\usepackage{acronym}

\hypersetup{linkcolor={\DocumentDefaultLinkColor}}


\xapptocmd{\equation}{\hypersetup{linkcolor={\DocumentDefaultEquationLinkColor}}}{}{}%
\xapptocmd{\endequation}{\hypersetup{linkcolor={\DocumentDefaultLinkColor}}}{}{}%

\begin{document}
    \chapter{Text}
    Some text where I want to have \ac{BRDF} as a visibly colored link and in 
    an equation would not want the symbol to be a colored link. See \ref{listofsymbols}

    \begin{equation}
        \acs{fBRDF} = \dots
    \end{equation}

    However it would be nice if it still was a link. It just should not have 
    any color.

    % Two acronym lists
    \chapter{List of Abbreviations}
    \begin{acronym}[GPS]
        \acro{BRDF}{Bidirectional Reflectance Distribution Function}
        \acro{RGB}{Red, Green, Blue}
    \end{acronym}

    \chapter{List of Symbols} \label{listofsymbols}
    \begin{acronym}[$f(\vec{l},\vec{v})$]
        \acro{fBRDF}[$f(\vec{l},\vec{v})$]{\acf{BRDF}}
    \end{acronym}

\end{document}