I don't understand why the string "shadowsize" is not already in the file because when I convert from format 474 to 489 it is added. So why is it not there when I convert from format 474 to 491.
We also get a consistent look with amsmath, so require esint or amsmath.
When resolving alternatives, do also take into account whether the package
is available. For this to work, we also need to test for amsmath.sty (which
was surprisingly not yet done).
The "save-as" part of the bug is fixed by extending the \textclass tag
such that, if a local layout file is used, its path relative to the
document directory is now stored together with the name. If a relative
path cannot be used, an absolute one is used but, in this case, the
document is not usable on a different platform.
The "copy" part is fixed by introducing a new \origin tag, which is
written when the file is saved. This tag stores the absolute path of
the document directory. If the document is manually copied to a
different location, the local layout file is retrivied by using
\origin (which is only updated on save).
This new tag may prove useful also for locating other files when the
document is manually moved to a different directory.
As in the original implementation the files needed for the layout
(for example, a latex class) had to be in the same directory as the
layout file, this directory has also to be added to TEXINPUTS.
Avoid that \newcommand[x] definitions of math macros are pushed multiple
times to the preview loader.
Redefinitions (via \renewcommand[x]) are properly handled.
If use of hyperref is detected, the postscript route is not attempted
(because we know it will fail) and the PDF route is directly chosen.
Also account for all upper case extensions for pdflatex image files.
Was forgetting this last bit from 64e0c558. Also give a message such
that the user is informed that not everything is lost if latex fails.
With this, the previews are generated also when the document directly
specifies a specific pdf output format.
This is a followup commit to 691fdea3 and restores the behavior of the
script as it was intended before 64e0c558, other than taking into account
possible inclusion of files that only pdflatex can process and the
possibility of multiple defined math macros.
The instant previews in the math manual now work again.
