[QGIS-Developer] Incorrect hidpi setting in 3.0 for OSX

[Alessandro Pasotti]

It's rather obscure to me too :)

For Qt 5.10 on Linux I use

QT_AUTO_SCREEN_SCALE_FACTOR to 0
QT_DEVICE_PIXEL_RATIO to 1


but on the same machine and display with Qt 5.9.3 I need to use

QT_AUTO_SCREEN_SCALE_FACTOR to 1
QT_DEVICE_PIXEL_RATIO to 2


in order to have the same effect, that is the SVG icons are not pixelated
neither are the Qt GUI elements (like checkboxes) which are actually too
small.


If I set QT_AUTO_SCREEN_SCALE_FACTOR to 1 QT_DEVICE_PIXEL_RATIO to 2 on
5.10 I get the correct size for the Qt GUI elements but I get pixelated SVG
icons.


I've not yet found the perfect solution.




On Mon, Feb 19, 2018 at 4:20 PM, Denis Rouzaud <denis.rouzaud at gmail.com>
wrote:

> Hi all,
>
> This always sounded very obscure to me...
> Alessandro, can you recommend any value to test?
>
> Cheers,
> denis
>
> Le lun. 19 févr. 2018 à 07:45, Alessandro Pasotti <apasotti at gmail.com> a
> écrit :
>
>> Hi,
>>
>> sorry if this does not apply to mac (I'm not a Mac user), but did you try
>> to experiment with the following environment variables?
>>
>> QT_AUTO_SCREEN_SCALE_FACTOR
>> QT_DEVICE_PIXEL_RATIO
>>
>> the effect may be different with different Qt versions and platforms.
>>
>>
>>
>> On Mon, Feb 19, 2018 at 7:32 AM, Jeremy Palmer <palmerjnz at gmail.com>
>> wrote:
>>
>>> Thanks for starting this thread Nyall.
>>>
>>> Ian not sure if it's relates to the HiDPI changes that occurred recently
>>> (e.g maptool cursors becoming small) but I've also noted that since Xmas
>>> the canvas is very sluggish when panning and zooming on Macosx and
>>> burning through many More CPU cycles than 2.18 for the same operations.
>>>
>>> Cheers
>>> Jeremy
>>>
>>> On 19/02/2018 19:14, "Nyall Dawson" <nyall.dawson at gmail.com> wrote:
>>>
>>>> Hey all (specifically OSX devs)
>>>>
>>>> From a few open bug reports we have against the OSX build of 3.0, I
>>>> gather that the OSX builds currently are not correctly handling hidpi
>>>> screens.
>>>>
>>>> My understanding is that the builds are silently trying to scale the
>>>> UI by pixel doubling/scaling - it's resulting in bugs like
>>>> https://issues.qgis.org/issues/18043,
>>>> https://issues.qgis.org/issues/17773, and
>>>> https://issues.qgis.org/issues/15984.
>>>>
>>>> Does any OSX expert know why this is happening? I think the automatic
>>>> pixel scaling should be switched off - while master isn't perfect with
>>>> hidpi screens, it's usable and the benefits of the hidpi
>>>> canvas/composer outweigh the remaining issues.
>>>>
>>>> Plus, I'd rather we use a single approach to hidpi scaling then have
>>>> to worry about separate code paths for OSX.
>>>>
>>>> Nyall
>>>> _______________________________________________
>>>> QGIS-Developer mailing list
>>>> QGIS-Developer at lists.osgeo.org
>>>> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>>>> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>>>
>>>
>>> _______________________________________________
>>> QGIS-Developer mailing list
>>> QGIS-Developer at lists.osgeo.org
>>> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>>> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>>>
>>
>>
>>
>> --
>> Alessandro Pasotti
>> w3:   www.itopen.it
>> _______________________________________________
>> QGIS-Developer mailing list
>> QGIS-Developer at lists.osgeo.org
>> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>
>


-- 
Alessandro Pasotti
w3:   www.itopen.it
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-developer/attachments/20180219/af67c030/attachment-0001.html>