[twg-tds] Question: how to include an image file in a document class?

[Reinhard Kotucha]

Ulrike, if I understand Lei's problem correctly, MiKTeX doesn't find
tex/latex/uowthesis/UoWlogo.png for some reason.  I can't believe it.
Can you reproduce the problem?


On 2015-09-13 at 04:08:32 +0000, Lei Ye wrote:

 > In the document "A Directory Structure for TEX Files" version 1.1, June
 > 23 2004, it defines the TDS texmf directory tree and use "texmf" to
 > refer to its root.
 > 
 > e.g.     texmf/doc

The TDS tells you where to *put* your files.  If you put them into the
right directories they will be found by your TeX system automatically.

 > Are there generic, platform-independent TEX variables like @TEXMF and
 > @TEXMFLOCAL to resolve the directory tree defined in TDS for both Tex
 > Live and MikTeX?
 > 
 > e.g. To allow any of the following to work:
 > 
 > \IfFileExists{\@TEXMFLOCAL /doc/latex/uowthesis/UoWlogo.png}
 > \includegraphics{\@TEXMFLOCAL /doc/latex/uowthesis/UoWlogo.png}

There is neither a need to specify a path nor is it desired.  Use

  \IfFileExists{UoWlogo.png}{}{}

and

  \includegraphics{UoWlogo.png}

instead and rely on your TeX system.  You can check it on the command
line.  On TeX Live I get

  $ kpsewhich UoWthesis.cls
  /xopt/texlive/2015/texmf-dist/tex/latex/uowthesis/UoWthesis.cls

and

  $ kpsewhich UoWlogo.png
  /xopt/texlive/2015/texmf-dist/tex/latex/uowthesis/UoWlogo.png

I suppose that on MiKTeX the first command works for you.  If the
second doesn't, please note that there are already 61 PNG files under
TEXMF/tex/latex.  I can't imagine that MiKTeX is unable to find any
of them.  Did you install the PNG file manually and forgot to update
the filename database?


 > \graphicspath{  {\@TEXMF /tex/latex/uowthesis/}  {\@TEXMFLOCAL
 > /tex/latex/uowthesis/}  {\@TEXMFLOCAL /doc/latex/uowthesis/} {\@TEXMF
 > /doc/latex/uowthesis/} }

I assume that you tried \graphicspath because something else went
wrong.  The short answer is "hands off!".

First of all, ***never*** use absolute paths.  

\graphicspath is supposed to contain a list of paths relative to the
location of a particular document.  It should never be used in .cls or
.sty files.

The original idea was to allow you to write

  \graphicspath{{photos/}{drawings/}}
  \includegraphics{my_dog.jpg}
  \includegraphics{my_house.pdf}

instead of

  \includegraphics{photos/my_dog.jpg}
  \includegraphics{drawings/my_house.pdf}

but the latter solution is much more efficient wrt TeX's memory
consumption.  Therefore \graphicspath is deprecated nowadays.  It
unnecessarily adds things to TeX's string pool without providing a
significant benefit to the user.

Regards,
  Reinhard

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