bug#25583: 26.0.50; :width/:max-width and vice versa in images

[Lars Ingebrigtsen <larsi@gnus.org>]

As far as I can tell, it isn't documented what should happen if you have
both :width and :max-height set in image specification, or vice versa.

Currently :width wins in this situation, but I think that's probably
just a coincidence.  (I mean, I implemented this, and I can't remember
considering that case...)

Here's the use case: I want to display images that are mostly square,
but can sometimes be rectangular, and I want them to be displayed in max
width if possible, even if they are smaller than that width originally,
but not exceeding a certain height.

So I thought ":width 400 :max-height 500" should do the trick, but
apparently compute_image_size just ignores :max-height in this case.

I think :max-height should "win" here... (That is, the width will end up
smaller than 400 if making it 400 wide will make height exceed 500.)

I'll implement this sometimes soon unless somebody objects or I think of
a reason why not...


In GNU Emacs 26.0.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.14.5)
 of 2017-01-30 built on stories
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-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no