Resolution indpendence

Behdad Esfahbod behdad at
Fri Jun 27 07:56:26 PDT 2008

On Fri, 2008-06-27 at 16:49 +0200, Soeren Sandmann wrote:
> Behdad Esfahbod <behdad at> writes:
> > On Fri, 2008-06-27 at 10:59 +0200, Soeren Sandmann wrote:
> > > The upcoming GNOME will simply set it to 96.
> > 
> > SRSLY?  That would be a regression.  Right now GNOME nicely detects my
> > 114dpi screen and uses right size fonts.  96 would look really
> > small.
> Bah, I knew I shouldn't have posted about this.
> (1) The number is fundamentally meaningless because an X "Screen" can
>     be made up of several physical screens.

Oh yeah, but 99.999% of cases, there's one X Screen and one physical

> (2) The DPI is insufficient to compute any font size anyway because
>     the right one also depends on the distance to the screen. You
>     really don't want 3 point fonts on a projector. You want
>     essentially the same size fonts as on your desktop. 

Read my other mail.  Take dpi as dpi-at-arms-distance and everything
makes sense again.  For a projector, assume distance from screen is the
same for the projector and the viewer and you have a fixed dpi defined.

> (3) Monitors often do not report a dpi, and when they do, they are
>     often wrong. Projectors don't have any way of knowing their dpi,
>     so some don't report any, and some claim to be 60" screens.

All laptops I've had correctly report their physical size.  We can
detect junk values (resulting in < 50 or > 300 dpi for example and use
some defaults.  Federico implemented that already IIRC).

> (4) You can override it in the control center anyway.

That's no reason.  It should Just Work.  And in this case, it has been
Just Working so far.  Just don't break it please.

> Søren

"Those who would give up Essential Liberty to purchase a little
 Temporary Safety, deserve neither Liberty nor Safety."
        -- Benjamin Franklin, 1759

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