bug#17792: 24.3; hintstyle specified via fontconfig is ignored by Emacs

[yynyygy]

I've noticed font rendering differences between Emacs and other gtk
applications like gedit. In short, Emacs ignores hintstyle setting in
fontconfig. I have hintstyle set to hintslight in
~/.config/fontconfig/fonts.conf, but I have to add 'Xft.hintstyle:
hintslight' in Xresources to get the desired effect.

The strange thing is that while ignoring hintstyle setting, Emacs still
respect part of fontconfig settings, for example, anti-aliasing setting
in fonts.conf will affect Emacs's font rendering.

To be more precise, if I disable anti-aliasing in fonts.conf and enable
it in Xresources, Emacs will not have anti-aliasing; if I have
hintslight in fonts.conf and hintnone in Xresources, Emacs will use
hintnone.

I have tested with DejaVu Sans Mono 12 and Ubuntu Mono 13, but clearly
it is not the fonts' problem.


In GNU Emacs 24.3.1 (x86_64-pc-linux-gnu, GTK+ Version 3.10.8)
 of 2014-06-11 on gentoo
Windowing system distributor `The X.Org Foundation', version 11.0.11500000
System Description:     NAME=Gentoo

Configured using:
 `configure '--prefix=/usr' '--build=x86_64-pc-linux-gnu'
 '--host=x86_64-pc-linux-gnu' '--mandir=/usr/share/man'
 '--infodir=/usr/share/info' '--datadir=/usr/share' '--sysconfdir=/etc'
 '--localstatedir=/var/lib' '--libdir=/usr/lib64'
 '--disable-silent-rules' '--disable-dependency-tracking'
 '--program-suffix=-emacs-24' '--infodir=/usr/share/info/emacs-24'
 '--localstatedir=/var'
 '--enable-locallisppath=/etc/emacs:/usr/share/emacs/site-lisp'
 '--with-crt-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.7.3/../../../../lib64'
 '--with-gameuser=games' '--without-compress-info' '--without-hesiod'
 '--without-kerberos' '--without-kerberos5' '--with-gpm' '--with-dbus'
 '--without-gnutls' '--without-xml2' '--without-selinux'
 '--without-wide-int' '--with-sound' '--with-x' '--without-ns'
 '--without-gconf' '--without-gsettings' '--without-toolkit-scroll-bars'
 '--with-gif' '--with-jpeg' '--with-png' '--with-rsvg' '--with-tiff'
 '--with-xpm' '--without-imagemagick' '--with-xft' '--without-libotf'
 '--without-m17n-flt' '--with-x-toolkit=gtk3'
 'GENTOO_PACKAGE=app-editors/emacs-24.3-r6'
 'build_alias=x86_64-pc-linux-gnu' 'host_alias=x86_64-pc-linux-gnu'
 'CFLAGS=-march=native -O2 -pipe' 'LDFLAGS=-Wl,-O1 -Wl,--as-needed'
 'CPPFLAGS=''

Important settings:
  value of $LC_COLLATE: C
  value of $LC_CTYPE: zh_CN.UTF-8
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=fcitx
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x r e p o r <tab> <return> C-y <backspace> <backspace> 
M-x M-p <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
current-kill: Kill ring is empty
delete-backward-char: Text is read-only [2 times]
Quit

Load-path shadows:
None found.

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