[Development] Qt High-dpi QtCS report and patch status (on hold)

[Mark Gaiser]

On Wed, Jul 2, 2014 at 2:33 PM, Sorvig Morten <Morten.Sorvig at digia.com> wrote:
> A quick report from the contributors summit (I apologize for the delay and sketchy notes):
>
> * I went though the general approach:
>
> - Setting the scale factor:
>         - platform plugin: QWindow::devicePixelRatio, QScreen::devicePixelRatio
>         - the user: QT_HIGHDPI_SCALE_FACTOR=2
>         - per-screen config file?
>
> - Layering
>         - QtWidgets / QtQuick / Application : device-independent pixels
>         - QPA: QWindow/QWindowSystemInterface :    scaling layer
>         - Platform plugins:  device pixels
>
> - QWindow and platform plugins
>         - setGemetry()/geometry() is in device-independent pixels
>         - platform plugins must scale when using QWindow API
>
> * There was discussion on several points:
>         - There are font kerning issues on Linux (and probably Windows) due to the scaling. How can we resolve this?
>         - Do we really want to add scaling to QtGui? The alternative is to wait until there is OS support.
>         - Windows and its three high-dpi modes.
>
> On to the patch status: (https://codereview.qt-project.org/#/c/86107/)
>
> Based on the patch reviews on gerrit and some discussion on irc I’ve decided that we don’t have a good enough consensus to merge the patches. I’m putting them on hold until after the summer break at least.
>
> Morten

Just a slight note of concern with this along with the idea to make Qt
5.4 or 5.5 an LTS version. Whatever you folks decide, please consider
including highdpi support in the version of Qt that is going to be the
LTS version. I ask because company's already tent to lag a couple
releases behind (or are still in 4.8.x). If a company updates they
prefer an upgrade to an LTS version. It's very much possible that this
upcoming LTS version is going to be used for years to come. Not having
highdpi support in there would be a missed opportunity imho.

Cheers,
Mark