Qt 5.14 Is Bringing Significantly Better HiDPI Support

[phoronix]

Phoronix: Qt 5.14 Is Bringing Significantly Better HiDPI Support

Besides KDE seeing its own HiDPI improvements like fractional scaling on Wayland recently landing, the Qt5 tool-kit is seeing more HiDPI improvements on its end too...

http://www.phoronix.com/scan.php?page=news_item&px=Qt-5.14-Better-HiDPI-Support

[aufkrawall]

I hope it will be helpful for the remaining fractional scaling issues of Plasma (thinking mostly of the terrible line artifacts).

[tildearrow]

Typo:

Wayland improvements, updatd Qt WebEngine, and much more

My scheme for world domination has faild!

By the way, that new Qt logo needs to not be stretched...

[tildearrow]

Also I have a question. Is it true that Qt renders the main widgets entirely on the CPU? If I remember GTK uses GPU assistance but apparently Qt doesn't...

[zanny]

Also I have a question. Is it true that Qt renders the main widgets entirely on the CPU? If I remember GTK uses GPU assistance but apparently Qt doesn't...

QWidgets are CPU rasterized, QML is GPU accelerated. Any new UI built on Qt should be using QML anyway instead of the old .ui widget files.

[tildearrow]

QWidgets are CPU rasterized, QML is GPU accelerated. Any new UI built on Qt should be using QML anyway instead of the old .ui widget files.

Does QML support the KDE themes and/or the ability to create normal desktop widgets? (e.g. Breeze)

[ssokolow]

Does QML support the KDE themes and/or the ability to create normal desktop widgets? (e.g. Breeze)

No. "Normal desktop widgets" are QWidget widgets and KDE themes are QWidget themes.

It's the #1 reason I've had no interest in learning QML. (The #2 reason being that Qt Quick 2's selection of widgets is still not as rich and featureful as the QWidget API's and I have no interest in doing extra work to bend yet another "all the world is a tablet/smartphone" widget set to the needs of proper desktop apps.)

[tildearrow]

No. "Normal desktop widgets" are QWidget widgets and KDE themes are QWidget themes.

It's the #1 reason I've had no interest in learning QML. (The #2 reason being that Qt Quick 2's selection of widgets is still not as rich and featureful as the QWidget API's and I have no interest in doing extra work to bend yet another "all the world is a tablet/smartphone" widget set to the needs of proper desktop apps.)

Dang.
I wish QWidgets could get some sort of GPU assistance... GTK3 already does so to some extent, and GTK4 will almost fully use the GPU for GUI rendering.

[carewolf]

QWidgets are CPU rasterized, QML is GPU accelerated. Any new UI built on Qt should be using QML anyway instead of the old .ui widget files.

Usually. You can render widgets using OpenGL as well, but unless you are transforming large images, it won't be any faster. It is up to platform backend to pick a default QPainter implementation, but most use the CPU one as it is quite fast and the most feature full. You can however get both an X11 backed one, a Direct2D one and an OpenGL one if you like. And you can override the defaults but using non default QWindows.

[RealNC]

Does QML support the KDE themes and/or the ability to create normal desktop widgets? (e.g. Breeze)

QML itself doesn't. But KDE Frameworks has a QtQuicControls2 style that does it. It's portable too, doesn't depend on KDE and can be used in stand-alone Qt applications:

https://api.kde.org/frameworks/qqc2-...tml/index.html

This is why QML UIs in KDE still use Breeze (or whatever theme you selected.) Also works for Windows and macOS where it will look native there too.