On 2015-09-20 at 22:24:33 -0400, Boris Veytsman wrote:

 > RK> Date:         Mon, 21 Sep 2015 03:51:44 +0200
 > RK> From: Reinhard Kotucha <[log in to unmask]>
 > 
 > 
 > RK> The viewport is specified in terms of pixels.  After downsampling the
 > RK> photos I had to change the viewport arguments (divide them by the
 > RK> downsampling factor).  This had to be done manually and thus was quite
 > RK> inconvenient.
 > 
 > RK> It would be quite handy to have an option which behaves similar to
 > RK> viewport but accepts arguments relative to the size of the original
 > RK> graphic, for instance [0.15 0.2 0.87 0.98].
 > 
 > I am sorry if this is an offtopic here, but the package rviewport in
 > LaTeX2e (full disclosure: written by me and paid for by the Food and
 > Agriculture Organization of the United Nations) does exactly this:
 > 
 >      \includegraphics[rviewport=0.15 0.2 0.87 0.98, clip]{image}
 > 
 > is the syntax of the package.
 > 
 > I have no objection, of course, if L3 uses this in the core graphics
 > instead of a contributed code.

Thanks, Boris.  This looks good.  It's a pity that I wasn't aware of
it a few weeks ago.

However, I asked for the feature on this list because I hope that
LaTeX~3 will have more functionality in its core packages so that the
number of required packages can be reduced.

Regards,
  Reinhard

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