Re: [ft-devel] Unix Font Performance/Rendering patches available

[David Turner]

Salut,


> I've pushed this patch in fontconfig cooker but as expected, I didn't
> saw any performance improvement since we are now using freetype 2.2.1.
>   
well, there is a slight performance increase, but you don't see it 
because fc-cache is now
losing most of its time in zlib's "inflate_fast' due to the large number 
of compressed pcf.gz
font files, as well as loading *each* glyph from every font file just to 
retrieve its advance and
check that it's not empty.

The current FreeType CVS contains improvements to glyph loading that 
speed the later
operation, but a nicer solution is to provide a specific function within 
FreeType to perform
the advance retrieval + empty check as fast as possible within the font 
engine (i.e. without
loading all glyph data).

I have a prototype version of FreeType and FontConfig that allow me to 
perform a font
cache regeneration in less than 4 seconds now, but that's only because I 
have decompressed
all pcf fonts in my /usr/lib/X11/fonts directories. I'll post everything 
when it's complete.

it's really time to complete fonttosfnt in order to get rid of pcf.gz 
font files, this is one dawn ugly
format, both in terms of performance and memory footprint !!

> I've tested the cairo patch and there are some problems with
> gnome-font-properties : 
>
> In "Details", test each hinting mode with subpixel rendering. Then,
> switch to graylevel rendering and switch hinting => fonts will be
> rendered as color subpixel rendering, except for "no hinting" settings.
>
> I didn't had time to investigate this problem more precisely (but I
> remember having this kind of issue when I initially rewrote the cairo
> hinting selection part, based on your earlier suggestion).
>
>   
I'm fully aware of this problem, and it's one of the reason why I didn't 
publish the patches before.
I have tried to find the bug numerous time in Cairo, without success. I 
hope we'll be able to get
rid of it some day, but at the moment I consider this to be an annoyance 
rather than a blocking
bug.

Regards,

- David Turner
- The FreeType Project  (www.freetype.org)


***********************************************************************************
Information contained in this email message is confidential and may be 
privileged, and is intended only for use of the individual or entity named 
above. If the reader of this message is not the intended recipient, or the 
employee or agent responsible to deliver it to the intended recipient, you are 
hereby notified that any dissemination, distribution or copying of this 
communication is strictly prohibited. If you have received this communication 
in error, please immediately notify the address@hidden and destroy the original 
message.
***********************************************************************************