[scribus-dev] Support for high DPI screens

[Khaled Hosny]

Hi,

I’m a bit interested in improving support for high DPI screens (such my
main machine has one). I recently sent a couple of patches to help
improve things:

* https://bugs.scribus.net/view.php?id=14004
  This improves the canvas rendering so that it does not very blurry on
  hi-DPI screens. AFAICT this should compile on any Qt 5 version (at
  least the used APIs has no version-specific annotations).

* https://bugs.scribus.net/view.php?id=13204
  This enables hi-DPI support without needing to set an env variable on
  X11 (my understanding that Qt on Windows, Mac OS X and Wayland enables
  hi-DPI automatically if the system supports it). This works only with
  Qt 5.6, and the code is #if’d as such, for older systems one has to
  manually set QT_DEVICE_PIXEL_RATIO env variable.

The most prominent hi-DPI issue remaining is the icons, currently Qt wil
just scslae them so they appear blurry. There are two ways to fix this,
use SVG icons or have two set of the icons (normal and hi-DPI) and the
code automatically selects between them. Either way if someone is
welling to work on the icon part, I can look into the code part of
loading the icon appropriately.

Regards,
Khaled