behdad at behdad.org
Fri Jun 27 08:51:49 PDT 2008
On Fri, 2008-06-27 at 17:41 +0200, Soeren Sandmann wrote:
> Behdad Esfahbod <behdad at behdad.org> writes:
> > On Fri, 2008-06-27 at 16:49 +0200, Soeren Sandmann wrote:
> > > Behdad Esfahbod <behdad at behdad.org> 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
> > screen.
> Majority of cases, yes, but not close to 99.999%. Dual head is not
May not be in computer software companies. But is quite uncommon in 1)
laptops on the road, 2) home computers. Yes, you connect your laptop to
a screen maybe for a presentation. Or you connect it to an external
monitor and switch to it. Anyway, even 90% is high enough to be worse
> > > (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.
> You are assuming here people view different-sized screens at the same
> distance, but that is just wrong.
I'm not. I'm saying that the dpi value you need is the distance
> There is a reason people look at a cell phone closer up than a monitor,
Do they? I don't.
> and at a monitor closer up than a movie theater.
> In fact, I believe people tend to look at screens at
> the distance that makes the angular resolution similar to what it is
> at 96 dpi.
Not at all. You can buy the same 15" laptop either with 1024x768
display or 1600x1200. Are you suggesting that people use those two
laptops at different distance??
> > > (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).
> Consider a 60" TV with a resolution of 1920x1080. This device has a
> dpi of 30, but if you use that value, you get really tiny fonts and
> you don't want that because you are looking at it from your couch, not
> at "arms length".
HAL sees that it's a TV, assumes a viewing distance of 4m, computes a
dpi-at-arms-distance value of 30 * 4/.7 = 171dpi. Very decent.
> Your algorithm above would consider it a "junk" value, but there is
> nothing junk about it. The TV is reporting it's size and resolution
> What *is* junk is attempting to compute stuff that cannot be
Like, trying to be user-friendly?
> > > (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.
> The "Just Work" solution is to pick 96 dpi because it works in 99.999%
> of cases. Users can select bigger or smaller fonts if they want to, or
> they can override the dpi setting.
> Believing the X dpi is apparently new in 2.22, so it hasn't been
> "working" so far.
Yeah, before that I had to do it manually. But I believe latest stable
GNOME works just fine.
"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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