The KDE Breeze icon set (that was mentioned recently on emacs-devel as a
potential for the toolbar) also does this.

~Chad

On Thu, Apr 23, 2020 at 12:59 PM Yuan Fu <casouri@gmail.com> wrote:

>
>
> > On Apr 23, 2020, at 3:40 PM, Eli Zaretskii <eliz@gnu.org> wrote:
> >
> >> From: Yuan Fu <casouri@gmail.com>
> >> Date: Thu, 23 Apr 2020 15:35:19 -0400
> >> Cc: Werner LEMBERG <wl@gnu.org>,
> >> Juri Linkov <juri@linkov.net>,
> >> Yuri Khan <yuri.v.khan@gmail.com>,
> >> Clément Pit-Claudel <cpitclaudel@gmail.com>,
> >> yandros@gmail.com,
> >> emacs-devel@gnu.org
> >>
> >> Apart from the font vs image discussion, what about the idea to add @2x
> images support to Emacs?
> >> WDYT? Basically, we add name@2x.xpm images along side the existing
> name.xpm images. And find-image
> >> would prefer those @2x images if, say, image-prefer-hidpi is non-nil.
> >
> > I don't think I understand what is meant by @2x images, but the
> > general idea of preferring certain variants of images given some
> > aspect of the environment is sound.
>
> On HiDPI monitors you can essentially display 200x200 pixels on the same
> area where normal monitors can display 100x100 pixels, hence the @2x.
> Application icons nowadays normally comes with @2x and @3x variants. So a
> 32x32 icon also comes with 64x64 and 96x96 size. At least that’s how is
> goes for iOS and macOS apps.
>
> Yuan