LateXdiff

To get an old revision (e.g 9fgvx...) saved as fileold.tex from a Git repository use:

$git log #to list revisions
$ git show 9fgvx:./file.tex > fileold.tex

Now, in order to get a nice PDF with the differences between two revisions, after install the corresponding program if necessary:

$ sudo apt-get install latexdiff

use the following:

$ cd latexdir
latexdir~$ latexdiff --flatten fileold.tex file.tex > file-diff.tex
latexdir~$ pdflatex file-diff.tex

option --flatten replace \input or \include by LaTeX content.

To install the magic script latexbatchdiff

and in order to compare with some old revision (e.g 9fgvx...)

latexdiff-git 9fgvx file.tex

If latexdiff fails, we could use the standard difftool: to compare two revision with(e.g fff68.. and a0d4d...) from a Git repository use:

$ git difftool fff68 a0d4d file