Re: Server side text layout

>

STSF was designed based on two of the most powerful, and feature rich
APIs in existence.  Those being Apple's ATSUI and Java's Java 2D Text
API.  Additonally, we consulted many experts within the font community
for input on the design of the API.  From what we have heard in the
developer community, these two APIs are appreciated for the capabilities
and robustness that they bring to the table.  STSF brings the same feature
sets and abilities to the Unix/Linux community for the first time.

For Sun, memory foot print is very important. Our systems include
multi-user Sunray servers supporting up to 200 users.  In this environment,
it is critical to have a single glyph cache that is available to all users
and applications.  This was one to the principal drivers for a server
side design.  The benifits of this approach are also available to all of the
other Sun hardware platforms and across the greater community as well.

We believe that STSF offers one of the best APIs in the industry, designed
from the top down to meet the needs of developers.  Further, it offers
excellent performance and an efficient memory footprint.  We feel that it
not only solves problems faced by Sun and other industry companies, but
has substantial benefits for all developers.

We are not asking the community for whole-sale replacement of existing
code.  That is one reason for creating the Xft-STSF bridge.  This brings
the performance and memory benefits to applications currently utilizing
that code.  Once people begin to see the advantages STSF offers, we
think that future application and current tool kits will provide methods
for using STSF directly to further take advantage of its capabilities.
Additionally, we support the use of tools such as FontConfig and plan to
offer even more extensive support within the STSF archetecture for them.


Jay Hobson
Sun Microsystems


> Date: Thu, 27 Mar 2003 18:27:44 -0500
> From: Havoc Pennington <[email protected]>
> To: [email protected]
> Subject: Re: Server side text layout (was Re: [forum] some XFree86 5.0 questions...)
> Reply-To: [email protected]
>
> On Thu, Mar 27, 2003 at 02:46:52PM -0800, Alan Coopersmith wrote:
> > Havoc Pennington wrote:
> > > We've just finished spending two years moving millions of lines of
> > > code *that Sun has just shipped* over to fontconfig/Xft/Pango. Do we
> > > want to do that again?
> >
> > Actually, while Sun's GNOME 2.0 release does use pango, I don't beleive
> > we've shipped a single line of code yet that uses fontconfig/Xft.  It's
> > certainly not in our GNOME 2.0 release.  Whether or not converting again
> > makes sense depends on whether there are enough benefits to make it
> > worthwile, just as that had to be decided when converting to pango
> > originally.
>
> Fair point, but do keep in mind that GNOME 2.2 has fontconfig as a
> hard requirement already, and GTK+ 2.4 will follow suit.
>
> Sun's GNOME 2.0 is a GNOME 2.0/2.2 hybrid (just like Red Hat Linux 8),
> our hybrid has already jumped to the fontconfig stuff from 2.2, yours
> has not, apologies.
>
> > The Xft bridge provides backwards compatibility for those who think the cost
> > of converting old code outweighs the benefits of converting code directly to
> > STSF, but that there is value in using STSF.
>
> Xft bridge provides back compat for the font rendering layer, not for
> the text layout layer or font configuration layer. The font rendering
> layer is the most trivial and least important of the layers.
>
> The porting cost I'm complaining about is that of changing the
> configuration and layout layers.
>
> Havoc
>