Opened 7 years ago
Last modified 7 years ago
#16249 new defect
Qt frontend doesn't set HiDPI attributes
| Reported by: | Andreas Schneider | Owned by: | |
|---|---|---|---|
| Component: | GUI | Version: | VirtualBox 5.1.10 |
| Keywords: | hidpi | Cc: | |
| Guest type: | all | Host type: | other |
Description
The VirtualBox Qt Frontend doesn't set HiDPI Qt attributes, so the the rendering on HiDPI display is horrible.
See the attached patch fixes the rendering of the management GUI. More details are at:
However the guest window still doesn't not render correctly. I think it uses images for that and needs to be adapted for that.
https://doc.qt.io/qt-5/qpainter.html#drawing-high-resolution-versions-of-pixmaps-and-images
So the attached patch is only half of the story.
Attachments (2)
Change History (9)
by , 7 years ago
| Attachment: | vbox_hidpi_support.patch added |
|---|
comment:1 by , 7 years ago
Well, the patch enables scaling for the Qt Frontend correctly. We do not want any scaling to the area where the guest is rendered. That's the missing part.
comment:2 by , 7 years ago
Hello,
Thanks for your report about this issue. It requires a bit of analysis first.
Which host (OS type and screen model, if that is separate monitor) are you using where you observe poor HiDPI scaling quality?
And where this quality is particularly poor? Application elements, icons or VM guest screen itself?
Is it the default HiDPI scaling ratio for your host or you had selected some advanced option?
comment:3 by , 7 years ago
Hi,
this happens on openSUSE 42.2 or openSUSE Tumbleweed (Linux). The desktop environment is latest stable KDE. I have a Eizo EV3237 with 3180x2160 resolution. Fonts DPI is set to 144. I use a scaling factor of 1.4.
The issue is the Guest window. I'm not able to click on the Guest window menu bar. It is also hard to click something in a guest itself. Often I need a double click where a normal click would be enough. The guest OS doesn't matter.
I will attach a screenshot. You can see that the Windows guest has steps in the fonts. The smaller the font the harder to read it. The attached screenshot shows a Windows Server screen before log in.
by , 7 years ago
| Attachment: | virtualbox.png added |
|---|
Screenshot showing the scaling issue in a Windows guest
comment:6 by , 7 years ago
The issue still exists in VirtualBox 5.1.14 but that's probably expected. The workaround I'm using for now is to unscale the UI so that it's rendered at native resolution and then use the guest OS features, such as UI scaling in Windows or DPI in Ubuntu, to make it larger. Technically I add an export to the launcher script but it's the same idea.
env QT_SCALE_FACTOR=0.5 VirtualBox
I'm running Fedora 25, Xorg, NVIDIA, GNOME 3, with a 28" Samsung UHD monitor. I run both an Ubuntu 14.04.5 guest and a Windows 10 RS1 guest.
comment:7 by , 7 years ago
A similar issue was just fixed in VLC. See https://trac.videolan.org/vlc/ticket/17484
Enable HiDPI support for the frontent