Resolution indpendence

Nicolas Mailhot nicolas.mailhot at
Sat Jun 28 01:26:17 PDT 2008

Le samedi 28 juin 2008 à 02:15 +0100, Glynn Clements a écrit :
> Sean Estabrooks wrote:
> > > I care about AA text. Specifically, it matters quite a lot to me that
> > > I never have to look at it. The only time that scalable fonts make
> > > sense is if you absolutely have to display some text at an exact size
> > > (i.e. desktop publishing). Even in cases where there are *some* layout
> > > constraints (e.g. diagrams), choosing the nearest bitmap font size is
> > > usually perfectly adequate.
> > 
> > As soon as you admit that there are cases where scalable fonts are desirable
> > you must begrudgingly accept that people will endeavor to support them.
> > This thread is not about a return to fixed-sized fonts, rather it is about
> > supporting scalable fonts (and other GUI elements) in a more consistent
> > manner.
> If only.
> Sure, there are cases where scalable fonts are desirable. I just wish
> that developers would not try to force them onto the other 95% of
> cases. The fonts used in a file manager or a text editor don't need to
> be some exact physical size on the screen.

The fonts used in a file manager or a text editor do need to stay the
same size when you move from one workstation to the next with a screen
with slightly different pixel size.

> And even in the cases where they are desirable (i.e. DTP), the thing
> that really matters is relative consistency, not absolute size.

You can't achieve consistency by relying on pixel sizes. Harware is not

> > Anyway, a system which supports scalable fonts can trivially support
> > pixel based fonts,
> It could, if the developers weren't so obsessed with physical sizes
> that they go out of their way to prevent you from using pixel sizes
> anywhere.

They don't go out of their way. In this thread there is one party that
consistently denies the need to satisfy the others' requirements that's

> > whereas the reverse just isn't true.  So far, i haven't
> > seen where any of your ideas can be used to improve scalable font
> > rendering.
> I'm not interested in scalable font rendering. I'm a computer
> programmer, not a graphic artist, and

This is pretty evident. Also it's pretty evident the "computer
programmer class that can't imagine anything but pixels" is a user
minority. It's over-represented when making decisions on software
features though (which explains a lot)

> my main use for a computer is to view and edit text.

Mine too. That does not change the fact I disagree with you.

> However, on the "improving" front, I have at least tried to remind
> people that "resolution independence" involves more than just fonts.

As you yourself noted text in the main information form on a screen and
just drives everything else.

> Possibly the biggest reason for hard-coded DPI assumptions is that
> people keep coming up with systems where text is measured in points
> and everything else is measured in pixels. At which point, you end up
> forcing a fixed "nominal" resolution so that everything works as
> expected on a wide range of displays.

There are bugs and we hide them under the carpet with dpi hacks. But we
don't hide them perfectly enough for people not to complain and the
carpet is beginning to stink.

Fix the bugs

> The second biggest reason for hard-coded DPI assumptions is that
> people keep coming up with systems where physical sizes are the only
> things that matter, essentially pretending that you have infinite
> resolution. At which point, everything has to be substantially
> over-sized, with even the thinnest lines being several pixels thick,
> otherwise everything becomes a faint blur.

The second biggest reason for hard-coded DPI assumptions is that some
programmers keep insisting it can't work, intentionnaly botch
implementations and then revert to dpi hacks (with self-satisfied I told
you so).

In other words, same reason as 1, bugs to be fixed

(Also most people are not eagle-eyed like you and wouldn't care less
about single-pixel wide fly dung text)

> Right now, a typical monitor still has a low enough resolution that
> single-pixel lines are common UI elements. If you try to design a UI
> where everything is specified in physical units, but has roughly the
> same dimensions on an average monitor as the pixel-based alternative,
> you end up with a blurred mess (or, without AA, a jagged mess) of
> near-unity-width lines, raster images scaled by near-unity factors,
> etc.

Still same reason as 1. There are bugs, it does not work, it'll never
work, see I was right not to spend energy on making it work, it's a
failure. I told you so.

> So you either oversize everything, or you end up having to hack
> in a fixed nominal DPI so that the resulting pixel sizes end up as
> integers.

So you don't have any pixel asumptions in the UI descriptions, and let
software libs compute dimensions, rounding them so they fall on the
pixel grid (which is BTW how text rendering already works, and it's more
complex than UI dimensionning).

You only have pixel assumptions today because of people that refuse to
imagine anything else could work.

> > > The notion that AA text is a good idea is a classic example of reverse
> > > reasoning. Starting with the quasi-religious ...
> > 
> > More proof that Goodwin's law needs to be updated to include accusations
> > of religiosity against anyone with a differing view.
> No, I have had plenty of disagreements with people for all kinds of
> reasons, and I don't normally imply quasi-religious motivations. I
> describe that position as quasi-religious because I think that it's,
> well, quasi-religious. And that's the only way that I can see this
> obsession with physical sizes.

It's not an obsession but a requirement. A requirement you go out of
your way to frustrate. Don't complain if that puts you in contact with
frustrated users.

> We managed to survive with a hard-coded 75 dpi for years. Windows was
> quite successful with a hard-coded choice of either 96 or 120 dpi (in
> spite of a few programs overlooking the 120 dpi possibility).

And windows has moved past it. As usual years late because the hardware
forced its hand.

In other news VGA was good enough for many years. Dump your fancy
screens and get a VGA-only one (See I can partain "wisdom" too. Does it
feel good to be on the "wisdom" receiving end?)

> But now, if the monitor says it's 121x124 dpi, apparently it's my
> responsibility to somehow choose a 20.167 x 20.667 point font to avoid
> it looking like crap.

Nope, it's your responsability to bug the authors of the apps you use so
they honor a desktop-wide prefered font setting, and so this setting can
optionnaly be expressed in pixels as you like it. (but don't even try to
argue the pt unit should be removed unless you're ready to have people
massively angry at you)

>  And it's also my responsibility to re-calculate
> those settings if I switch monitors.

Oh, dear me, you complain about having to re-calculate settings when
changing hardware, when your position so far is that everyone should
re-calculate fake dpi settings when switching monitors (except for the
minority that dreams in pixels).

Get your head out of the sand, the only way for everyone to coexistate
peacefully is for preferred font sizes to be expressed in explicit
(pixel or pt units), with users choosing the unit (and scaling model)
they prefer.

If you insist on not providing this facility you'll have to share the
system dpi value with everyone else, and everyone else does not agree
with your pixel preference.

Nicolas Mailhot
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