bug#12273: 24.2.50; complex text layout

[Peter Dyballa]

Hello!

Last weekend I built I built one Emacs X client with Fink as 32-bit application 
using these libraries:

        /sw/lib/fontconfig2/lib/libfontconfig.1.dylib (compatibility version 
8.0.0, current version 8.2.0)
        /sw/lib/freetype219/lib/libfreetype.6.dylib (compatibility version 
16.0.0, current version 16.0.0)
        /sw/lib/gnutls28/libgnutls.28.dylib (compatibility version 36.0.0, 
current version 36.1.0)
        /usr/X11/lib/libICE.6.dylib (compatibility version 10.0.0, current 
version 10.0.0)
        /sw/lib/libm17n-core.0.dylib (compatibility version 5.0.0, current 
version 5.0.0)
        /sw/lib/libm17n-flt.0.dylib (compatibility version 5.0.0, current 
version 5.0.0)
        /sw/lib/libMagickCore.5.dylib (compatibility version 6.0.0, current 
version 6.0.0)
        /sw/lib/libMagickWand.5.dylib (compatibility version 6.0.0, current 
version 6.0.0)
        /sw/lib/libotf.0.dylib (compatibility version 1.0.0, current version 
1.0.0)
        /usr/X11/lib/libSM.6.dylib (compatibility version 7.0.0, current 
version 7.0.0)
        /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current 
version 125.2.11)
        /usr/X11/lib/libX11.6.dylib (compatibility version 9.0.0, current 
version 9.0.0)
        /sw/lib/libXaw3d.8.dylib (compatibility version 9.0.0, current version 
9.1.0)
        /sw/lib/libxml2.2.dylib (compatibility version 11.0.0, current version 
11.0.0)
        /usr/X11/lib/libXmu.6.dylib (compatibility version 9.0.0, current 
version 9.0.0)
        /usr/X11/lib/libXrender.1.dylib (compatibility version 5.0.0, current 
version 5.0.0)
        /usr/X11/lib/libXt.6.dylib (compatibility version 7.0.0, current 
version 7.0.0)
        /sw/lib/ncurses/libncurses.5.dylib (compatibility version 5.0.0, 
current version 5.0.0)
        /sw/lib/xft2/lib/libXft.2.dylib (compatibility version 5.0.0, current 
version 5.0.0)

and a 64-bit application with MacPorts using these libraries:

        /opt/local/lib/libfontconfig.1.dylib (compatibility version 7.0.0, 
current version 7.0.0)
        /opt/local/lib/libfreetype.6.dylib (compatibility version 16.0.0, 
current version 16.0.0)
        /opt/local/lib/libgconf-2.4.dylib (compatibility version 6.0.0, current 
version 6.5.0)
        /opt/local/lib/libgdk_pixbuf-2.0.0.dylib (compatibility version 
2601.0.0, current version 2601.2.0)
        /opt/local/lib/libgif.4.dylib (compatibility version 6.0.0, current 
version 6.7.0)
        /opt/local/lib/libgio-2.0.0.dylib (compatibility version 3201.0.0, 
current version 3201.4.0)
        /opt/local/lib/libglib-2.0.0.dylib (compatibility version 3201.0.0, 
current version 3201.4.0)
        /opt/local/lib/libgnutls.26.dylib (compatibility version 49.0.0, 
current version 49.3.0)
        /opt/local/lib/libgobject-2.0.0.dylib (compatibility version 3201.0.0, 
current version 3201.4.0)
        /opt/local/lib/libICE.6.dylib (compatibility version 10.0.0, current 
version 10.0.0)
        /opt/local/lib/libjpeg.8.dylib (compatibility version 13.0.0, current 
version 13.0.0)
        /opt/local/lib/libMagickCore.5.dylib (compatibility version 6.0.0, 
current version 6.0.0)
        /opt/local/lib/libMagickWand.5.dylib (compatibility version 6.0.0, 
current version 6.0.0)
        /opt/local/lib/libncurses.5.dylib (compatibility version 5.0.0, current 
version 5.0.0)
        /opt/local/lib/libotf.0.dylib (compatibility version 1.0.0, current 
version 1.0.0)
        /opt/local/lib/libpng14.14.dylib (compatibility version 27.0.0, current 
version 27.0.0)
        /opt/local/lib/librsvg-2.2.dylib (compatibility version 39.0.0, current 
version 39.1.0)
        /opt/local/lib/libSM.6.dylib (compatibility version 7.0.0, current 
version 7.1.0)
        /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current 
version 125.2.11)
        /opt/local/lib/libtiff.3.dylib (compatibility version 13.0.0, current 
version 13.5.0)
        /opt/local/lib/libX11.6.dylib (compatibility version 10.0.0, current 
version 10.0.0)
        /opt/local/lib/libXaw3d.8.dylib (compatibility version 9.0.0, current 
version 9.0.0)
        /opt/local/lib/libXft.2.dylib (compatibility version 6.0.0, current 
version 6.1.0)
        /opt/local/lib/libxml2.2.dylib (compatibility version 10.0.0, current 
version 10.8.0)
        /opt/local/lib/libXmu.6.dylib (compatibility version 9.0.0, current 
version 9.0.0)
        /opt/local/lib/libXpm.4.dylib (compatibility version 16.0.0, current 
version 16.0.0)
        /opt/local/lib/libXrender.1.dylib (compatibility version 5.0.0, current 
version 5.0.0)
        /opt/local/lib/libXt.6.dylib (compatibility version 7.0.0, current 
version 7.0.0)

So the Fink variant uses libm17n and a modern libotf with 
OTF_get_variation_glyphs and the MacPorts variant has a bit older software. I 
launched both with -Q and them display the HELLO file and edited it to contain 
only complex scripts. I made a screenshot of both Emacsen side by side and made 
from the Fink variant's display a transparent copy with text colour in red and 
tried to position that over the same part of the edited HELLO buffer in the 
other Emacs. A few differences are visible. I cannot judge whether these 
differences are improvements, except for one: the Gujarati word in () seems to 
be in the m17n enabled Fink variant not OK – there is a low "accent" moved to 
the opening parenthesis.

I am attaching the constructed image. It shows on the left the Fink variant 
with libm17n enabled and on the right the MacPorts variant with a bit 
old-fashioned or no software.

--
Greetings

  Pete

Eternity is a terrible thought. I mean, where's it going to end?
                                - Tom Stoppard