Beamer: control logo horizontal position in the header

Question

I'm dealing with a presentation, and I need to put the logo at the top right of the header. This a MWE from which my code is inspired:

\documentclass{beamer}

\usetheme{metropolis}

\makeatletter
\setbeamertemplate{frametitle}{%
  \nointerlineskip%
  \begin{beamercolorbox}[%
      wd=\paperwidth,%
      sep=0pt,%
      leftskip=\metropolis@frametitle@padding,%
      rightskip=\metropolis@frametitle@padding,%
    ]{frametitle}%
  \metropolis@frametitlestrut@start%
  \insertframetitle%
  \nolinebreak%
  \metropolis@frametitlestrut@end%
  \hfill
  \raisebox{-0.6ex}{\includegraphics[height=3ex,keepaspectratio]{example-image-duck}}
  \end{beamercolorbox}%
}
\makeatother

\begin{document}

\begin{frame}{My frame title}
 \begin{block}{Some itemize}
  \begin{itemize}
   \item \alert{Item 1}
   \item Item 2
  \end{itemize}
 \end{block}
 \begin{block}{Some maths}
 \[\sum_{n=1}^{\infty}\frac{1}{n^2}=\frac{\pi^2}{6}=\zeta(2)\]
\end{block}
\end{frame}

\end{document}

I would like to know how I could control the horizontal position of the logo in the header. I mean, \raisebox allows to control the vertical position, so which command should I use to achieve horizontal control? I need to move slightly on the left the logo, because my actual code places the logo too much close to the right edge.

Answer 1

UPDATED

In your MWE replace \hfill with a (negative) horizontal space.

In the code set \rightgap to move the logo to the left side of the frame.

\documentclass{beamer}      

\newlength{\rightgap}
\setlength{\rightgap}{30pt} % adjust to move the logo to the left<<<<<<<

\usetheme{metropolis}

\makeatletter
\setbeamertemplate{frametitle}{%
    \nointerlineskip%
    \begin{beamercolorbox}[%
        wd=\paperwidth,%
        sep=0pt,%
        leftskip=\metropolis@frametitle@padding,%
%       rightskip=\metropolis@frametitle@padding,%
        ]{frametitle}%
        \metropolis@frametitlestrut@start%
        \parbox{0.85\paperwidth}{\insertframetitle}% changed <<<<<
        \nolinebreak%
        \metropolis@frametitlestrut@end%
%       \hfill
        \hspace*{-\rightgap} % move the logo to the left<<<<<<<     
        \raisebox{-0.8ex}{\includegraphics[height=3ex,keepaspectratio]{example-image-duck}}
    \end{beamercolorbox}%
}
\makeatother

\begin{document}        

    \begin{frame}{My frame title}
        \begin{block}{Some itemize}
            \begin{itemize}
                \item \alert{Item 1}
                \item Item 2
            \end{itemize}
        \end{block}
        \begin{block}{Some maths}
            \[\sum_{n=1}^{\infty}\frac{1}{n^2}=\frac{\pi^2}{6}=\zeta(2)\]
        \end{block}
    \end{frame}

    \begin{frame}{My frame long long long long long long long title}
    \begin{block}{Some itemize}
        \begin{itemize}
            \item \alert{Item 1}
            \item Item 2
        \end{itemize}
    \end{block}
    \begin{block}{Some maths}
        \[\sum_{n=1}^{\infty}\frac{1}{n^2}=\frac{\pi^2}{6}=\zeta(2)\]
    \end{block}
\end{frame} 
    
\end{document}