Re: The Gnus logo in the modeline is displayed with a non-transparent background

[Robert Pluim <rpluim@gmail.com>]

asjo@koldfront.dk (Adam Sjøgren) writes:

> The advice I am using on find/create-image¹ is fixing the opposite
> problem: images being too small on HiDPI screens.

Too small and too big are symptoms of the same problem: not applying
the scaling factor correctly :-)

> The only problem with it was the tiny Gnus-logo in the modeline, which
> has its transparent background turned white, when the :type is changed
> from 'xpm to 'imagemagick (by the advice).
>
>> Iʼve fixed a number of scaling issues in Emacs, but more always seem
>> to pop up (Which version of Emacs is this, BTW?)
>
> Cool, thanks! What kind of issues should I keep an eye out for? (I'm
> currently running master at a140513acb).

That commit has all the current fixes.  Frame positioning, menu
positioning and font scaling should all be ok, except there are known
issues with the interaction between menus and scaling.

> ¹ This is the current incarnation I use to get images scaled up on HiDPI
> displays:
>
>   (defadvice find-image (after scale-image-size activate)
>     "Scale the image size."
>     (condition-case nil
>         (let* ((magnitude (frame-parameter nil 'image-dpi-scale-magnitude))
>                (image (copy-sequence ad-return-value))
>                (size (image-size image t))
>                (spec (cdr image))
>                (image-width (or (plist-get spec :width) (car size)))
>                (image-height (or (plist-get spec :height) (cdr size))))
>           (plist-put spec :width (round (* image-width magnitude)))
>           (plist-put spec :height (round (* image-height magnitude)))
>           (when (not (string= (plist-get spec :type) "xpm")) ; skip xpm files, such as emacs/etc/images/gnus/gnus-pointer.xpm
>             (plist-put spec :type 'imagemagick))
>           (setq ad-return-value image))
>       (error nil)))
>
> where image-dpi-scale-magnitude is set to 150 on HiDPI displays and 100
> on non-HiDPI.

150?! That seems very high. Iʼd expect values like 1.5 or 2.

Perhaps image-size is not scaling correctly, Iʼll see if I can find anything.

Robert