Producing TikZ-made .pdfs and using /includegraphics on them?

Question

I'm helping TeX a professor's handwritten notes for publishing/pre-print purposes, and for producing certain graphics, I use PGF/TikZ. However, it seems he is having trouble compiling the code whenever TikZ is involved, so he wants me to compile the TikZ images separately, and then \includegraphics on all of them instead. (Seems a bit of a crime, but boss' orders I guess.)

However, trying to make the TikZ images standalone (i.e. including the TikZ code, some article document class, then compiling to .pdf), I am left with a huge amount of whitespace coming from the rest of the single page document. This leads to a lot of problems trying to \includegraphics with it, as the image itself is miniscule compared to all the blank space.

Is there a way to shorten the produced pages to fit exactly the dimensions of the TikZ-images? Or aside from dropping TikZ and going with a third party software, is there perhaps a better solution overall?

Answer 1

As mentioned you can use a package which mimics the internals of a tikzpicture but requiring that the images created by the external library are included.

This is very well explained in the manual of pgf, but I will explain how to use it.

First of, your regular local document will be having regular tikzset commands etc.

So:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{external}
\tikzexternalize
\begin{document}

Text ... 

\tikzsetnextfilename{arrow}
\begin{tikzpicture}
  \draw [->] (0,0) -- (2,3);
\end{tikzpicture}

\end{document}

This will create the document with the externalized picture creating a picture named arrow.pdf.

Now lets imagine you are done and wish to collaborate with a non-TikZian. This will probably also mean that he does not have any pgf/tikz packages installed.

1. First thing is to find the file tikzexternal.sty, it should be located in your TeX-tree under:

    latex/pgf/utilities/tikzexternal.sty
   

2. Copy this file to your main-TeX file folder.

3. Comment out your \usepackage{tikz,pgf,pgfplots}.

4. Comment out any \usetikzlibrary, \usepgfplotslibrary, etc.

5. Add the usage of the package \usepackage{tikzexternal}.

6. You do not need to comment out any \tikzset commands as that will be emulated away

The above things which should be commented out, can be performed by local \iffalse ... \fi statements, but the explicit comment out is more rigorous when distributing it to others.

This should give you a document like so:

\documentclass{article}
\usepackage{tikzexternal}
\tikzexternalize
\begin{document}

Text ... 

\tikzsetnextfilename{arrow}
\begin{tikzpicture}
  \draw [->] (0,0) -- (2,3);
\end{tikzpicture}

\end{document}

And compile to find that TikZ is not used, but loading of the image is correct.

However, there are some caveats in using this method. First off, the entire key-value system in keys are not present. Hence, all references to external settings should be performed using the designated commands:

1. Use \tikzsetexternalprefix instead of the key prefix
2. Use \tikzsetfigurename instead of the key figure name
3. Not even the content in \tikzexternalize[<content>] will be recognized.

Also, the package tikzexternal gobbles the tikzpicture environment, hence the full environment should be visible (don't do any fancy things here :) ).