Font rendering, 2015

[Michael Catanzaro]

On Tue, 2015-06-09 at 10:40 -0400, Matthew Miller wrote:
> Okay, so, here we go again with this... well, actually, hoping *not*
> to, but one specific thing keeps coming up. As far as I know,
> the patents affecting freetype expired, and the "freetype-freeworld"
> package from third party repositories no longer has any special 
> sauce.

Subpixel rendering is still disabled in the Fedora freetype package,
due to patents that have not expired: 
https://en.wikipedia.org/wiki/Subpixel_rendering#Patents

I think we just need to accept that we can't have good font rendering
until they expire.

> Yet, I still see people swearing up and down that this makes a big
> difference, it's included in "making fonts in Fedora look good" 
> guides
> everywhere — even though that patent expiration was now long ago. And 
> I
> see that in RPMFusion, the "freetype-freeworld" package still exists
> and is regularly updated.
> 
> So, what's going on with this? My uneducated guess is that the
> "freeworld" package simply enables autohinting that we have off by
> default and does not contain any magic sauce. Is this correct?

Fedora supports autohinting without installing anything extra, just
change hint type to Light (codeword for "autohint") in Tweak Tool.
Autohinting does not usually work as well as normal hinting, so it's
good that it's not used by default.

> (On the other hand "Infinality" is a set of patches to Freetype, and
> appears specifically tuned for various sets of non-free fonts.)

The best description of Infinality I've found is 
http://www.infinality.net/forum/viewtopic.php?f=2&t=18

Highlight: "These modifications essentially cause the Truetype
interpreter in Freetype to ignore hinting in the X direction, giving a
Cleartype-like result (unlike many pre-existing so-called "cleartype" packages for various distros). The default Truetype interpreter in 
Freetype renders fonts "correctly", in that it follows the instructions
given to it by the font. For legacy fonts (Arial, Verdana, Times, etc.)
these instructions were created with the idea that the end
rasterization of the font would be monochrome, i.e. Black and White
pixels only."