Sure.
There are a number of patents, held/applied for by Microsoft, covering various
aspects of sub-pixel rendering of text/images. Here is an example, though a
search engine will discover more...

http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=WO0021068&F=0

Some argue that these patents are un-enforcable due to prior art. See
http://www.grc.com/ctwho.htm  for an overview.

Microsoft indicates that it will license their implementation of sub-pixel
antialiasing (a.k.a. ClearType ) for between one and three US Dollars per
device. See here for more details...

http://www.microsoft.com/mscorp/ip/tech/cleartype.asp

Apple hold patents for portions of the TrueType hinting mechanisms. The Freetype
library source code is distributed in such a manner that it may be compiled with
or without the patent restricted code. When compiled without, a patent-free
auto-hinting mechanism is employed, which is not as good as the patented code,
but far better than nothing. For more information, see...

http://www.freetype.org/patents.html

So, it seems acceptable to distribute patent restricted stuff in source form,
and let the user decide what they compile/install/use. The new BitBlt mode does
not use any patented code. And so a VM with Freetype plugin/library compiled to
use the non-patented auto-hinter, and the modified BitBlt, will be patent free.
The sub-pixel stuff, entirely in Smalltalk, and distributed as source, would
then be an optional install.

But, of course, I'm not a lawyer :)
Cheers,
Andy



----- Original Message ----- 
From: "stéphane ducasse" <ducasse at iam.unibe.ch>
Newsgroups: gmane.comp.lang.smalltalk.squeak.general
Sent: Thursday, March 30, 2006 9:11 AM
Subject: Re: Henrik antialising


> Hi andy
>
> could you explain a bit more the issues with the patents and the
> license?
>
> Stef
> On 29 mars 06, at 16:55, Andrew Tween wrote:
>
> > I'll see if I can package up a modified Windows VM with Freetype
> > plugin, the new
> > BitBlt mode for sub-pixel, and a semi-stable 3.8Full image. That
> > way, at least
> > the people
> > with Windows can have a play.
> > I think I need to remove the sub-pixel code from the image and make
> > it a
> > changeset, due to
> > the patent issue.
> > I also need to double check that when I built the freetype lib, I
> > didn't compile
> > it with the
> > patented truetype hinting enabled.
> > Patents, don't you just love 'em :)
> >
> > Does anybody know if it would be ok to put this stuff on
> > ftp.squeak.org ?
> >
> > Cheers,
> > Andy
> >
> > ----- Original Message -----
> > From: "Lord ZealoN" <lordzealon at gmail.com>
> > Newsgroups: gmane.comp.lang.smalltalk.squeak.general
> > Sent: Wednesday, March 29, 2006 3:16 PM
> > Subject: Re: Henrik antialising
> >
> >
> > I can have this in 3.8?
> >
> > 2006/3/29, Diego Gomez Deck <DiegoGomezDeck at consultar.com>:
> >> Great!
> >>
> >> I can't wait to get a version running on my Squeak.
> >>
> >> Cheers,
> >>
> >> -- Diego
> >>
> >>> Here is a screenshot similar to the one Bert posted, but this
> >>> time with
> >>> sub-pixel anti-aliasing applied.
> >>> This will only look o.k. on an LCD monitor with vertical striping
> >>> in RGB
> > order.
> >>> Cheers,
> >>> Andy
> >>>
> >>> ----- Original Message -----
> >>> From: "Diego Gomez Deck" <DiegoGomezDeck at consultar.com>
> >>> Newsgroups: gmane.comp.lang.smalltalk.squeak.general
> >>> Sent: Thursday, March 23, 2006 1:11 PM
> >>> Subject: Re: Henrik antialising
> >>>
> >>>
> >>>> Hi Andrew,
> >>>>
> >>>>> I've now got everything installed (in a 3.8 image), and the
> >>>>> Vera fonts
> > are
> >>>>> rendering correctly.
> >>>>> It looks very good.
> >>>>
> >>>> Please send the mandatory screenshot.
> >>>>
> >>>> Cheers,
> >>>>
> >>>> -- Diego
> >>
> >>
> >>
> >>
> >
> >
> > --
> >
> > ::Mi blog::
> > http://blog.lordzealon.com
> >
> >
>
>
>