How to disable the Qt automatic HiDPI scaling?

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

How to disable the Qt automatic HiDPI scaling?

Frederic Muller
Hi!

I run GNOME on a 2560x1440 resolution display where I disabled the "double scaling" (not sure how it's called). So one pixel is one dot. Unfortunately when running Qt applications such as VLC for example they autoscale to 1 dot for 4 pixels making those huge and taking most of my display area. When on dual screen they even recognize which screen is HiDPI and therefore automatically scale back on the non HiDPI screen kind of forcing me to run all my Qt apps on that external screen. Unfortunately I do not always have an external screen to save me...

So is there a way (like with GNOME) to disable this feature and have Qt apps display "normally"?

Thank you.

Fred

_______________________________________________
users mailing list -- [hidden email]
To unsubscribe send an email to [hidden email]
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: How to disable the Qt automatic HiDPI scaling?

Ed Greshko
On 08/09/2017 11:03 AM, Frederic Muller wrote:

> Hi!
>
> I run GNOME on a 2560x1440 resolution display where I disabled the "double scaling"
> (not sure how it's called). So one pixel is one dot. Unfortunately when running Qt
> applications such as VLC for example they autoscale to 1 dot for 4 pixels making
> those huge and taking most of my display area. When on dual screen they even
> recognize which screen is HiDPI and therefore automatically scale back on the non
> HiDPI screen kind of forcing me to run all my Qt apps on that external screen.
> Unfortunately I do not always have an external screen to save me...
>
> So is there a way (like with GNOME) to disable this feature and have Qt apps
> display "normally"?
FYI, this is a guess on my part since I've not had to deal with this issue.

I think I would look to http://doc.qt.io/qt-5/highdpi.html and see how these
environment variables may be help...

QT_AUTO_SCREEN_SCALE_FACTOR [boolean] enables automatic scaling, based on the pixel
density of the monitor. This will not change the size of point sized fonts, since
point is a physical unit of measure. Multiple screens may get different scale factors.
QT_SCALE_FACTOR [numeric] defines a global scale factor for the whole application,
including point sized fonts.
QT_SCREEN_SCALE_FACTORS [list] specifies scale factors for each screen. This will not
change the size of point sized fonts. This environment variable is mainly useful for
debugging, or to work around monitors with wrong EDID information(Extended Display
Identification Data).


--
Fedora Users List - The place to go to speculate endlessly


_______________________________________________
users mailing list -- [hidden email]
To unsubscribe send an email to [hidden email]

signature.asc (235 bytes) Download Attachment
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

[solved] Re: How to disable the Qt automatic HiDPI scaling?

Frederic Muller
On 08/09/2017 10:18 AM, Ed Greshko wrote:
On 08/09/2017 11:03 AM, Frederic Muller wrote:
Hi!

I run GNOME on a 2560x1440 resolution display where I disabled the "double scaling"
(not sure how it's called). So one pixel is one dot. Unfortunately when running Qt
applications such as VLC for example they autoscale to 1 dot for 4 pixels making
those huge and taking most of my display area. When on dual screen they even
recognize which screen is HiDPI and therefore automatically scale back on the non
HiDPI screen kind of forcing me to run all my Qt apps on that external screen.
Unfortunately I do not always have an external screen to save me...

So is there a way (like with GNOME) to disable this feature and have Qt apps
display "normally"?
FYI, this is a guess on my part since I've not had to deal with this issue.

I think I would look to http://doc.qt.io/qt-5/highdpi.html and see how these
environment variables may be help...

QT_AUTO_SCREEN_SCALE_FACTOR [boolean] enables automatic scaling, based on the pixel
density of the monitor. This will not change the size of point sized fonts, since
point is a physical unit of measure. Multiple screens may get different scale factors.
QT_SCALE_FACTOR [numeric] defines a global scale factor for the whole application,
including point sized fonts.
QT_SCREEN_SCALE_FACTORS [list] specifies scale factors for each screen. This will not
change the size of point sized fonts. This environment variable is mainly useful for
debugging, or to work around monitors with wrong EDID information(Extended Display
Identification Data).

Thanks a lot, that worked great! (I thought I tried those before but I guess I didn't do it right). At the end I've created a /etc/profile.d/qt.sh file and inserted this parameter inside:
export QT_AUTO_SCREEN_SCALE_FACTOR=0

Very happy now :-)

Thank you.

Fred

_______________________________________________
users mailing list -- [hidden email]
To unsubscribe send an email to [hidden email]
Loading...