[Sugar-devel] F11 for XO1 - Fonts

[Daniel Drake]

2009/8/4 Tomeu Vizoso <tomeu at sugarlabs.org>:
>> A method to specify the font size (measured in points).
>
> What font size would be that?

That would be up to the deployments.
For example, OLPC would choose 7.

> I guess we should, for improved accessibility. And would be convenient
> if the paddings, line widths, icon sizes, etc also scaled accordingly
> (may not be possible with current gtk+).

Not yet, but there are ongoing efforts to create an overall "scale
factor"-like system that will be nice.

> I don't hate it in itself. But I need to know better why using Xft.dpi
> is not a good solution (real technical disadvantages) and which
> mechanism uses gtk+/gnome so we can reuse their work there.

It's going against an established system that ensures that fonts of
the same point size are the same physical dimensions when shown on
different screens and on paper.

To me it also just doesn't make sense... if the fonts are too small,
then the logical thing is to use bigger fonts, not to start pretending
that you have a screen with different characteristics from the one
that you are using. This would also be important to deployments where
technical resources are lesser - at least to me, thinking of font size
in terms of the size of the font (a familiar concept to MS word
users!) is much more logical than thinking about the number of pixels
in a square inch on the display on which the fonts will be rendered.
(for example, for someone unfamiliar with that line of thinking, it is
not obvious whether you should increase or decrease the DPI in order
to make the fonts bigger)

Freetype visually optimizes the font renderings based on the DPI and
sometimes gives odd-looking results when the selected DPI is not that
of the actual display. (ever seen the subpixel rendering option result
in worse appearance than before? this is usually the cause)

It also will confuse any applications that make calculations based on
the DPI of the fonts against the millimetre-width of the screen --
although these are not that common.

GNOME use this same kind of approach. GNOME ships default font sizes
and has an "Appearance" dialog with a fonts tab that lets you increase
or decrease the font size. KDE is similar.

Daniel