Resolution indpendence

Nicolas Mailhot nicolas.mailhot at
Fri Jun 27 08:40:08 PDT 2008

Le Ven 27 juin 2008 17:02, Steven J Newbury a écrit :
> 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:

>> (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.
> This is true; there should be a viewing distance component too.

Actually, not. Except for videoprojectors the vast majority of
computer screens is at about the same distance from viewers, so you
don't need to correct physical DPI by distance to get about the same
physical meaning for xxpt size for everyone. And when you have walls
of screens they definitely are all at the same distance from the

Embedded is somewhat specific but again what you care is that the
physical text displayed by your gadget is about the same size when you
change the pixel density from one gadget generation to the other, not
about exact angle of view (which can change dynamicaly anyway)

Videoprojectors get treated like TV (little range of resolution,
assumed average distance, no text compensation scaling).

The viewing distance component is definitely not required to do

If you'd believe 96dpi proponents, it would never be possible to
achieve standardized text sizes without complex angle of view or
distance tinkering, when books and paper media prove every day of the
year a 11pt physical size does have meaning regardless of the exact
distance people use to read their moring paper.

Nicolas Mailhot

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