Re: Does Freetype work best with gamma 2.2, and how does it interact with KDE gamma setting?

[Rob]

Perhaps it's outside the scope of this mailing list, but in that case should I 
calibrate my monitor to a gamma of 1.7 to get the best text rendering?

On the other hand, this link indicates that a relative system gamma of "1.0" is 
equivalent to 2.2 on windows, so perhaps a monitor calibrated to 2.2 is 
actually correct.
https://docs.kde.org/stable5/en/kgamma5/kcontrol/kgamma5/index.html 
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On May 4 2021, at 11:29 am, Allan Sandfeld Jensen <linux@carewolf.com> wrote:
> Qt5 uses a gamma of 1.7 for text rendering on X11.
>
> The KDE gamma slider is an effect on the whole screen, not how elements are
> blended together inside singular apps.
>
> Not sure there is any other place we could read an expected gamma from on
> Linux, the only other source is using real gamma from monitors EDID, but that
> would result in a much higher gamma and lighter text, probably not fitting
> user expectations. Though perhaps we ought to have a switch allowing users
> to use real numbers instead of simulating traditional mistakes.
>
> Allan
> On Dienstag, 4. Mai 2021 12:20:38 CEST Rob wrote:
> > Ok, I understand.
> >
> > I am using KDE so I guess qt5 is responsible for gamma correction (and
> > probably assumes monitor is 2.2).
> > On May 4 2021, at 10:53 am, Werner LEMBERG <wl@gnu.org> wrote:
> > > > But if it is correcting the gamma it must assume that my monitor has
> > > > a certain gamma?
> > >
> > > As Allan has written: FreeType does *not* interact with gamma at all!
> > > If you want to be very precise you could say that FreeType doesn't
> > > return bitmaps with color or grayscale pixels. Instead, it returns
> > > *coverage* values (i.e., how much area of a pixel is covered by ink),
> > > and the calling graphics library has to further process it. This
> > > includes application of gamma correction.
> > >
> > >
> > > Werner
>