todonotes and tikzexternalize

Question

In my document I use todonotes and TikZ/pgfplots. After activating the externalization in TikZ I realized that todonotes are all exported as well (because they are based on TikZ).

This behaviour is inconvenient, it would be much better for me to tell tikz-external to ignore all \todo.

I know I can generally disable the externalization with \tikzset{external/export=false} and turn it on only for selected plots, but the inverse would be more convenient.

Answer 1

I had this very problem a while ago, just for the \todo command (I never use \missingfigure). Here's how I fixed it (place this in your preamble, somewhere after todonotes and tikz/pgfplots is called):

\makeatletter
\renewcommand{\todo}[2][]{\tikzexternaldisable\@todo[#1]{#2}\tikzexternalenable}
\makeatother

Now, \todo will be ignored by the externalization process.

Hence, for the \missingfigure command you need

\makeatletter
\renewcommand{\missingfigure}[2][]{\tikzexternaldisable\@missingfigure[#1]{#2}\tikzexternalenable}
\makeatother

Answer 2

For me neither of the proposed solutions worked. Maybe it is platform-dependent, taking into consideration the significant number of up-votes in favor of the accepted answer.

However, mSSM's approach with \let was close. The reason for it not to work properly with \missingfigure is that the latter consumes an optional argument. The simple \let fails to copy all required information to a new macro. According to this piece, one should use the letltxmacro package. Eventually, my working version is:

\usepackage{letltxmacro}

\LetLtxMacro{\oldmissingfigure}{\missingfigure}
\renewcommand{\missingfigure}[2][]{\tikzexternaldisable\oldmissingfigure[{#1}]{#2}\tikzexternalenable}

\LetLtxMacro{\oldtodo}{\todo}
\renewcommand{\todo}[2][]{\tikzexternaldisable\oldtodo[#1]{#2}\tikzexternalenable}

Answer 3

I have played around with \missingfigure, but a simple \renewcommand{\missingfigure}... will not work, as given in the answer by @Frits.

The only solution I found was defining a new command:

\newcommand{\extmissingfigure}[2][]{\tikzexternaldisable\missingfigure[#1]{#2}\tikzexternalenable}

Working with \let, i.e.:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{external}
\usepackage{todonotes}

\tikzexternalize

\let\oldmissingfigure\missingfigure
\renewcommand{\missingfigure}[2][]{\tikzexternaldisable\oldmissingfigure[#1]{#2}\tikzexternalenable}

\begin{document}

\missingfigure{Ah!}

\end{document}

unfortunately raises an error:

! TeX capacity exceeded, sorry [input stack size=5000].
<to be read again> 
\tikzexternal@orig@tikzfadingfrompicture 
l.18 \missingfigure{Ah!}