<Swing Dev> [9] Review request for 8058742: Text size is twice bigger under GTK L&F on Gnome with HiDPI enabled

[Semyon Sadetsky]

On 8/2/2016 6:25 PM, Sergey Bylokhov wrote:
> On 29.07.16 19:06, Semyon Sadetsky wrote:
>> On 29.07.2016 14:30, Sergey Bylokhov wrote:
>>> On 26.07.16 22:05, Semyon Sadetsky wrote:
>>>>> It is actually directly related to the global scale, since support of
>>>>> Xft/ was added in JDK-4830281 as a way to scale java UI. And now the
>>>>> new solution and the old one conflicts. Can we skip the usage of
>>>>> gnome.Xft if default device scale is not identity (which means that
>>>>> some other scale factor is used)?
>>>> Do you mean if native scale > 1 then to use scale=1 for GTK font size?
>>>> That will give the same result I guess.
>>>
>>> Did you try to implement it? In this case the gnome.Xft will be used
>>> only if no other scale was set, it should work like described below:
>> Once again Xft.dpi cannot be used as global scale directly. This bug is
>> not about global scale.
>
> But I don't suggest to use it as a global scale, use it only if other 
> scales were not set(default transform is 1).
That also means that it will go to the global UI scale on Linuxes which 
are not gnome/unity based. And the only difference with the current 
solution that on such Linux DEs Java apps will receive some uncontrolled 
scale because testing of unsupported OSes is out of the scope. If this 
topic bothers you I suggest to create a separate bug to investigate how 
the native scale may be supported on different Linux flavors using the 
Xft.dpi env var.  Without that we may get complains that the scale 
becomes wrong on unsupported Linuxes and DEs even when hidpi is not used 
in the native desktop at all.

--Semyon
>
>>>>  - Take debug scale into account if it was set and skip all others.
>>>>  - Check J2D_UISCALE
>>>>  - Check scale-factor, text-scale-factor, text-scaling-factor.
>>>>  - Check Xft.dpi.
>>>>  - If non of them was set then scale=1 should be used.
>>>
>>
>
>