HarfBuzz on MacOS

HarfBuzz on MacOS

[Pankaj Jangid]

I have following output from pkg-config:

pankaj@Pankajs-MacBook-Pro emacs % pkg-config --libs "harfbuzz >= 1.2.3"
-L/usr/local/Cellar/harfbuzz/2.6.4/lib -lharfbuzz
pankaj@Pankajs-MacBook-Pro emacs % pkg-config --cflags "harfbuzz >= 1.2.3"
-I/usr/local/Cellar/harfbuzz/2.6.4/include/harfbuzz
-I/usr/local/Cellar/glib/2.62.2/include/glib-2.0
-I/usr/local/Cellar/glib/2.62.2/lib/glib-2.0/include
-I/usr/local/opt/gettext/include -I/usr/local/Cellar/pcre/8.43/include
-I/usr/local/Cellar/graphite2/1.3.13/include

But even when I use "./configure --with-harfbuzz", the output of
configure script is

...
Does Emacs use -lgnutls?                                yes
Does Emacs use -lxml2?                                  yes
Does Emacs use -lfreetype?                              no
Does Emacs use HarfBuzz?                                no
...

I have two questions now.

1. Does HarfBuzz make any difference on MacOS?
2. Why HarfBuzz is not selected by the configure script?

I am building on MacOS 10.15.1, Emacs commit is
2e92f176a3ae68ed6fcf9f07c173c61a497f33fd.

Regards,
-- 
Pankaj Jangid

Re: HarfBuzz on MacOS

[Robert Pluim]

>>>>> On Mon, 18 Nov 2019 10:21:32 +0000, Pankaj Jangid <p4j@j4d.net> said:

    Pankaj> I have following output from pkg-config:
    Pankaj> pankaj@Pankajs-MacBook-Pro emacs % pkg-config --libs "harfbuzz >= 1.2.3"
    Pankaj> -L/usr/local/Cellar/harfbuzz/2.6.4/lib -lharfbuzz
    Pankaj> pankaj@Pankajs-MacBook-Pro emacs % pkg-config --cflags "harfbuzz >= 1.2.3"
    Pankaj> -I/usr/local/Cellar/harfbuzz/2.6.4/include/harfbuzz
    Pankaj> -I/usr/local/Cellar/glib/2.62.2/include/glib-2.0
    Pankaj> -I/usr/local/Cellar/glib/2.62.2/lib/glib-2.0/include
    Pankaj> -I/usr/local/opt/gettext/include -I/usr/local/Cellar/pcre/8.43/include
    Pankaj> -I/usr/local/Cellar/graphite2/1.3.13/include

    Pankaj> But even when I use "./configure --with-harfbuzz", the output of
    Pankaj> configure script is

    Pankaj> ...
    Pankaj> Does Emacs use -lgnutls?                                yes
    Pankaj> Does Emacs use -lxml2?                                  yes
    Pankaj> Does Emacs use -lfreetype?                              no
    Pankaj> Does Emacs use HarfBuzz?                                no
    Pankaj> ...

    Pankaj> I have two questions now.

    Pankaj> 1. Does HarfBuzz make any difference on MacOS?
    Pankaj> 2. Why HarfBuzz is not selected by the configure script?

HarfBuzz is currently only checked for when building on Windows or for
X11. On macOS the build defaults to the NS backend, not X11. Even if
configure detected HarfBuzz, I donʼt think the code is in place to
actually use it on mac.

Robert

Re: HarfBuzz on MacOS

[Pankaj Jangid]

>>>>> Robert Pluim <rpluim@gmail.com> writes:
>     Pankaj> I have two questions now.
>     Pankaj> 1. Does HarfBuzz make any difference on MacOS?
>     Pankaj> 2. Why HarfBuzz is not selected by the configure script?
> HarfBuzz is currently only checked for when building on Windows or for
> X11. On macOS the build defaults to the NS backend, not X11. Even if
> configure detected HarfBuzz, I donʼt think the code is in place to
> actually use it on mac.

Thanks Robert.

Another question: will this make any difference on MacOS when it is
supported?

Regards,
--
Pankaj

Re: HarfBuzz on MacOS

[Robert Pluim]

>>>>> On Mon, 18 Nov 2019 10:56:22 +0000, Pankaj Jangid <p4j@j4d.net> said:

>>>>> Robert Pluim <rpluim@gmail.com> writes:
    Pankaj> I have two questions now.
    Pankaj> 1. Does HarfBuzz make any difference on MacOS?
    Pankaj> 2. Why HarfBuzz is not selected by the configure script?
    >> HarfBuzz is currently only checked for when building on Windows or for
    >> X11. On macOS the build defaults to the NS backend, not X11. Even if
    >> configure detected HarfBuzz, I donʼt think the code is in place to
    >> actually use it on mac.

    Pankaj> Thanks Robert.

    Pankaj> Another question: will this make any difference on MacOS when it is
    Pankaj> supported?

I donʼt know. Coretext works well enough for me, but perhaps it has
deficiencies that aren't obvious to me. Certainly it would be nice to
only have to worry about one shaping library.

Robert

Re: HarfBuzz on MacOS

[Pankaj Jangid]

Robert Pluim <rpluim@gmail.com> writes:
> I donʼt know. Coretext works well enough for me, but perhaps it has
> deficiencies that aren't obvious to me. Certainly it would be nice to
> only have to worry about one shaping library.

Yes. That is for sure better.

Re: HarfBuzz on MacOS

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Date: Tue, 19 Nov 2019 14:39:48 +0100
> Cc: emacs-devel <emacs-devel@gnu.org>
> 
>     Pankaj> Another question: will this make any difference on MacOS when it is
>     Pankaj> supported?
> 
> I donʼt know. Coretext works well enough for me, but perhaps it has
> deficiencies that aren't obvious to me. Certainly it would be nice to
> only have to worry about one shaping library.

Yes, we should strive to support HarfBuzz on all GUI platforms.
Volunteers are welcome to work on that support on macOS.

Re: HarfBuzz on MacOS

[Robert Pluim]

>>>>> On Tue, 19 Nov 2019 18:18:00 +0200, Eli Zaretskii <eliz@gnu.org> said:

    >> From: Robert Pluim <rpluim@gmail.com>
    >> Date: Tue, 19 Nov 2019 14:39:48 +0100
    >> Cc: emacs-devel <emacs-devel@gnu.org>
    >> 
    Pankaj> Another question: will this make any difference on MacOS when it is
    Pankaj> supported?
    >> 
    >> I donʼt know. Coretext works well enough for me, but perhaps it has
    >> deficiencies that aren't obvious to me. Certainly it would be nice to
    >> only have to worry about one shaping library.

    Eli> Yes, we should strive to support HarfBuzz on all GUI platforms.
    Eli> Volunteers are welcome to work on that support on macOS.

I have a vague memory of Yamamoto-san having a preliminary patch for
macOS, but I canʼt locate it right now.

Robert

Re: HarfBuzz on MacOS

[YAMAMOTO Mitsuharu]

On Wed, 20 Nov 2019 01:30:49 +0900,
Robert Pluim wrote:
> 
> >>>>> On Tue, 19 Nov 2019 18:18:00 +0200, Eli Zaretskii <eliz@gnu.org> said:
> 
>     >> From: Robert Pluim <rpluim@gmail.com>
>     >> Date: Tue, 19 Nov 2019 14:39:48 +0100
>     >> Cc: emacs-devel <emacs-devel@gnu.org>
>     >> 
>     Pankaj> Another question: will this make any difference on MacOS when it is
>     Pankaj> supported?
>     >> 
>     >> I donʼt know. Coretext works well enough for me, but perhaps it has
>     >> deficiencies that aren't obvious to me. Certainly it would be nice to
>     >> only have to worry about one shaping library.
> 
>     Eli> Yes, we should strive to support HarfBuzz on all GUI platforms.
>     Eli> Volunteers are welcome to work on that support on macOS.
> 
> I have a vague memory of Yamamoto-san having a preliminary patch for
> macOS, but I canʼt locate it right now.

It's not public.  I used it just to test if the interface design
(begin_hb_font and end_hb_font in struct font_driver) is appropriate.

I'm currently reluctant to have multiple font backends on macOS
because of Bug#36835, especially if HarfBuzz doesn't have practical
advantages over the Core Text shaper.

				     YAMAMOTO Mitsuharu
				mituharu@math.s.chiba-u.ac.jp

Re: HarfBuzz on MacOS

[Eli Zaretskii]

> Date: Thu, 21 Nov 2019 14:03:54 +0900
> From: YAMAMOTO Mitsuharu <mituharu@math.s.chiba-u.ac.jp>
> Cc: Eli Zaretskii <eliz@gnu.org>,
> 	p4j@j4d.net,
> 	emacs-devel@gnu.org
> 
> I'm currently reluctant to have multiple font backends on macOS
> because of Bug#36835, especially if HarfBuzz doesn't have practical
> advantages over the Core Text shaper.

Bug#36835 is not specific to macOS, so if we allow multiple font
backends on Posix platforms, where this bug happens, why avoid that on
macOS?

Of course, I'd prefer that we fixed that bug, and sooner rather than
later, but other than that, having all modern platforms support and
use HarfBuzz is IMO an important development goal for Emacs, certainly
if the alternative is proprietary software.

Thanks.