Help with Tamil (Indic) font (Emacs from bzr)

Help with Tamil (Indic) font (Emacs from bzr)

[Jambunathan K]

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This question pertains to

        M-x set-input-method RET tamil-trans RET

I am on Debian (Squeeze) running XFCE.  


The attached screenshot shows the difference in behaviour between Emacs
launched from Bzr (trunk) and Emacs23 that is distributed with Debian
itself.  The character that is shown is the one you get by typing "ki"
in tamil-itrans.

You will note following differences:

1. Emacs23 uses Lohit font while EmacsBzr picks up gnu-unifont.
2. Emacs23 "composes" the glyphs correctly while EmacsBzr messes up the
   display.

I have the following in .emacs.

    (set-face-font 'default "fontset-default")
    (set-fontset-font "fontset-default" 'tamil "Lohit Tamil")

and xterm reports the following.

    ,----
    | kjambunathan@debian-6:~$ fc-list :lang="ta"
    | TSCu_Paranar:style=Bold
    | TSCu_Times:style=Normal
    | TAMu_Maduram:style=Normal
    | FreeSerif:style=Medium,Mittel,µεσαία,Normal,Gemiddeld,navadno
    | TSCu_Comic:style=Normal
    | TAMu_Kadambri:style=Regular
    | TAMu_Kalyani:style=Regular
    | Lohit Tamil:style=Regular
    | unifont:style=Medium
    | TSCu_Paranar:style=Regular
    `----

I would like to get Emacs23 behaviour in EmacsBzr.  Why do the two
Emacs'es behave differently?  What settings do I need to tweak?

I am not much familiar with X Desktop environment and I have built my
Emacs in no special way (i.e., in a way any newcomer would).


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-- 

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Andreas Schwab]

Jambunathan K <kjambunathan@gmail.com> writes:

> 1. Emacs23 uses Lohit font while EmacsBzr picks up gnu-unifont.

When I try with emacs-23.3 and current trunk, both choose TSCu_Paranar
for both characters.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Jambunathan K]

Andreas Schwab <schwab@linux-m68k.org> writes:

> Jambunathan K <kjambunathan@gmail.com> writes:
>
>> 1. Emacs23 uses Lohit font while EmacsBzr picks up gnu-unifont.
>
> When I try with emacs-23.3 and current trunk, both choose TSCu_Paranar
> for both characters.

I am confused.  You need to ELI5 - explain like I am five!

How about the resulting glyph.  Do they superspose or do they stand
apart?

My .emacs explicitly says "Lohit Tamil" and I do have Lohit
installed.

        (set-face-font 'default "fontset-default")
        (set-fontset-font "fontset-default" 'tamil "Lohit Tamil")

    ,----
    | kjambunathan@debian-6:~$ fc-list :lang="ta"
    | TSCu_Paranar:style=Bold
    | TSCu_Times:style=Normal
    | TAMu_Maduram:style=Normal
    | FreeSerif:style=Medium,Mittel,µεσαία,Normal,Gemiddeld,navadno
    | TSCu_Comic:style=Normal
    | TAMu_Kadambri:style=Regular
    | TAMu_Kalyani:style=Regular
    | Lohit Tamil:style=Regular   <==========  desired
    | unifont:style=Medium        <==========  jambu sees this
    | TSCu_Paranar:style=Regular  <==========  schwab sees this
    `----



>
> Andreas.

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Wolfgang Jenkner]

On Wed, Jan 16 2013, Jambunathan K wrote:

> The attached screenshot shows the difference in behaviour between Emacs
> launched from Bzr (trunk) and Emacs23 that is distributed with Debian
> itself.  The character that is shown is the one you get by typing "ki"
> in tamil-itrans.
>
> You will note following differences:
>
> 1. Emacs23 uses Lohit font while EmacsBzr picks up gnu-unifont.
> 2. Emacs23 "composes" the glyphs correctly while EmacsBzr messes up the
>    display.


Please take a look at

src/config.h

and check that these lines

    /* Define to 1 if using libm17n-flt. */
    #define HAVE_M17N_FLT 1

    /* Define to 1 if using libotf. */
    #define HAVE_LIBOTF 1

are present.  If not see 

* Complex Text Layout support libraries

in the INSTALL file in the emacs top-level directory.  Given that this
works in your distro's emacs 23 you should already have the necessary
libraries, but perhaps they are too old or configure can't find them
(config.log should give a clue).

Wolfgang

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Andreas Schwab]

Jambunathan K <kjambunathan@gmail.com> writes:

> How about the resulting glyph.  Do they superspose or do they stand
> apart?

Character composition only works when the characters to be composed come
from the same font.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Jambunathan K]

Wolfgang Jenkner <wjenkner@inode.at> writes:

> On Wed, Jan 16 2013, Jambunathan K wrote:
>
>> The attached screenshot shows the difference in behaviour between Emacs
>> launched from Bzr (trunk) and Emacs23 that is distributed with Debian
>> itself.  The character that is shown is the one you get by typing "ki"
>> in tamil-itrans.
>>
>> You will note following differences:
>>
>> 1. Emacs23 uses Lohit font while EmacsBzr picks up gnu-unifont.
>> 2. Emacs23 "composes" the glyphs correctly while EmacsBzr messes up the
>>    display.
>
>
> Please take a look at
>
> src/config.h
>
> and check that these lines
>
>     /* Define to 1 if using libm17n-flt. */
>     #define HAVE_M17N_FLT 1
>
>     /* Define to 1 if using libotf. */
>     #define HAVE_LIBOTF 1
>
> are present.  If not see 

You guessed it right.  EmacsFromBzr is failing to pick up those
libraries.  I am seeing following lines in src/config.h.

    ,---- src/config.h
    | /* Define to 1 if using libotf. */
    | /* #undef HAVE_LIBOTF */
    | 
    | /* Define to 1 if using libm17n-flt. */
    | /* #undef HAVE_M17N_FLT */
    `----


I did a 
        bzr clean-tree --ignored 

and then ran
        ./autogen.sh
        ./configure

and this is what configure is reporting.

    ,----
    |   Does Emacs use -lxml2?                                  yes
    |   Does Emacs use -lfreetype?                              no
    |   Does Emacs use -lm17n-flt?                              no  <==
    |   Does Emacs use -lotf?                                   no  <==
    |   Does Emacs use -lxft?                                   no  <==
    `----

> * Complex Text Layout support libraries
>
> in the INSTALL file in the emacs top-level directory.  Given that this
> works in your distro's emacs 23 you should already have the necessary
> libraries, but perhaps they are too old or configure can't find them
> (config.log should give a clue).

I do have the required m17n and otf libraries - both runtime and dev
variations.  Am I missing any other libraries?

Should I file a bug report?

,----
| kjambunathan@debian-6:~/src/emacs/trunk$ ldd `which emacs23` | grep otf
| 	libotf.so.0 => /usr/lib/libotf.so.0 (0xb6b5b000)
| 
| kjambunathan@debian-6:~/src/emacs/trunk$ ldd `which emacs23` | grep m17n
| 	libm17n-flt.so.0 => /usr/lib/libm17n-flt.so.0 (0xb6a84000)
| 	libm17n-core.so.0 => /usr/lib/libm17n-core.so.0 (0xb6a5f000)
`----

,----
| kjambunathan@debian-6:~$ dpkg -l | grep m17n
| ii  libm17n-0                                       1.6.1-1                        a multilingual text processing library - runtime
| ii  libm17n-dev                                     1.6.1-1                        a multilingual text processing library - development
| ii  m17n-contrib                                    1.1.11-1                       a multilingual text processing library - contributed database
| ii  m17n-db                                         1.6.1-2                        a multilingual text processing library - database
`----

,----
| kjambunathan@debian-6:~$ dpkg -l | grep otf
| ii  libotf-dev                                      0.9.11-1                       A Library for handling OpenType Font - development
| ii  libotf0                                         0.9.11-1                       A Library for handling OpenType Font - runtime
`----

>
> Wolfgang

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Wolfgang Jenkner]

On Wed, Jan 16 2013, Jambunathan K wrote:

> You guessed it right.  EmacsFromBzr is failing to pick up those
> libraries.  I am seeing following lines in src/config.h.
>
>     ,---- src/config.h
>     | /* Define to 1 if using libotf. */
>     | /* #undef HAVE_LIBOTF */
>     | 
>     | /* Define to 1 if using libm17n-flt. */
>     | /* #undef HAVE_M17N_FLT */

> I do have the required m17n and otf libraries - both runtime and dev
> variations.  Am I missing any other libraries?

Do you have the freetype2 headers (probably in
/usr/include/freetype2/freetype)?

> Should I file a bug report?

I don't think so...

Wolfgang

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Eli Zaretskii]

> From: Jambunathan K <kjambunathan@gmail.com>
> Date: Thu, 17 Jan 2013 00:36:51 +0530
> 
> You guessed it right.  EmacsFromBzr is failing to pick up those
> libraries.  I am seeing following lines in src/config.h.
> 
>     ,---- src/config.h
>     | /* Define to 1 if using libotf. */
>     | /* #undef HAVE_LIBOTF */
>     | 
>     | /* Define to 1 if using libm17n-flt. */
>     | /* #undef HAVE_M17N_FLT */
>     `----
> 
> 
> I did a 
>         bzr clean-tree --ignored 
> 
> and then ran
>         ./autogen.sh
>         ./configure
> 
> and this is what configure is reporting.
> 
>     ,----
>     |   Does Emacs use -lxml2?                                  yes
>     |   Does Emacs use -lfreetype?                              no
>     |   Does Emacs use -lm17n-flt?                              no  <==
>     |   Does Emacs use -lotf?                                   no  <==
>     |   Does Emacs use -lxft?                                   no  <==
>     `----
> 
> > * Complex Text Layout support libraries
> >
> > in the INSTALL file in the emacs top-level directory.  Given that this
> > works in your distro's emacs 23 you should already have the necessary
> > libraries, but perhaps they are too old or configure can't find them
> > (config.log should give a clue).
> 
> I do have the required m17n and otf libraries - both runtime and dev
> variations.  Am I missing any other libraries?
> 
> Should I file a bug report?

Before you file a bug report, look into your config.log for clues why
the configure script decided you didn't have these libraries
installed.  It could be some issue with your system configuration, or
maybe you didn't install some development-related package for these
libraries, or some other local calamity.

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Jambunathan K]

Wolfgang Jenkner <wjenkner@inode.at> writes:

> On Wed, Jan 16 2013, Jambunathan K wrote:
>
>> You guessed it right.  EmacsFromBzr is failing to pick up those
>> libraries.  I am seeing following lines in src/config.h.
>>
>>     ,---- src/config.h
>>     | /* Define to 1 if using libotf. */
>>     | /* #undef HAVE_LIBOTF */
>>     | 
>>     | /* Define to 1 if using libm17n-flt. */
>>     | /* #undef HAVE_M17N_FLT */
>
>> I do have the required m17n and otf libraries - both runtime and dev
>> variations.  Am I missing any other libraries?
>
> Do you have the freetype2 headers (probably in
> /usr/include/freetype2/freetype)?

Thanks for the hint which guided me to dig inside configure.ac.

I have installed two additional packages - libfreetype6-dev and
libxft-dev.  The Tamil characters are now displayed correctly and shows
up in the right font.

ps-1:
----

I am wondering whether `* Complex Text Layout support libraries' section
of INSTALL file should mention availability of both xft and freetype
headers.

ps-2:
-----

I remember doing a
        apt-get build-dep emacs

to automatically pull the needed dependencies.  I now see that 

        apt-rdepends emacs | grep xft

doesn't show up libxft-dev.  (Likewise for libfreetype6-dev)  This
partly explains why CTL support was turned off in EmacsFromBzr.

Anyways, my problem is solved and the solution is recorded here for
others to run with.
-- 

Re: Help with Tamil (Indic) font (Emacs from bzr)

[Stephen J. Turnbull]

Jambunathan K writes:

 > I am wondering whether `* Complex Text Layout support libraries'
 > section of INSTALL file should mention availability of both xft and
 > freetype headers.

No, IMO this is a generic bug in configure.  It should check for
libraries first, then headers.  If the library needed to provide a
requested feature is present, but not the headers, it should bitch.

NB In INSTALL, somewhere near the top, you'll probably find a warning
about the perverse behavior (from the free software point of view) of
free software distributions which provide libraries for running
software but not the headers needed to build software.