Saving Canvas as TeX

(16 August 2013)

Being able to generate TeX graphics can be useful for several reasons:

  • To have an easy to modify the image, in particular the labels and titles (ASCII file).
  • To have the same font in all labels, legends, plot titles etc. as in the text body of a document.
  • Render Math formulae using TeX.

The TeX text engine is powerful and can render any complex math formulae. But more tricky is the graphics rendering: lines, polygons, markers etc … One possibility is to render them using PDF or PostScript and render the text using TeX. But that’s not very practical as two files are needed to render one picture. A better way is to use a dedicated environment like PGF/TikZ.

“ PGF (A Portable Graphic Format for TeX) is a macro package for creating graphics. It is platform- and format-independent and works together with the most important TeX backend drivers, including pdftex and dvips. It comes with a user-friendly syntax layer called TikZ. “

The new class TTeXDump allows to generate PGF/TikZ files. To generate a such file in ROOT it is enough to do:


Then, the generated file (hpx.tex) can be included in a LaTeX document (simple.tex) in the following way:

\title{A simple LaTeX example}
\date{July 2013}
The following image as been generated using the TTeXDump class.
To include it in a LaTeX document it is enough to specify the following
three directives at the top of the LaTex document:
Then to include the picture ({\tt hpx.tex} in this case) in a LateX
 document it is done the usual way:
\caption{Image ({\tt hpx.tex}) generated thanks to {\tt TTeXDump}}