desktop-packages team mailing list archive

[Zhou Yi Chao <145604@xxxxxxxxxxxxxxxxxx>]

I am trying to enable subpixel rendering on poppler and I found my
rendering result is suboptimal.  After gdbing into cairo, I am surprise
that cairo is still using the legacy filter as the "default".  To the
the situation even worse, cairo removed the interfaces to set the
lcdfiler (cairo_font_options_set_lcd_filter) because "they are too
specific to FreeType".

Well, maybe that is true.  But now how can I use the real Freetype
default filter (FIR5) in the newest cairo without pathcing it?  I think
maybe manually set a FcPattern is OK but I really do not want to
learn/invoke/rely Fontconfig just for setting a filter that should be
default.

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to cairo in Ubuntu.
https://bugs.launchpad.net/bugs/145604

Title:
  VRGB sub-pixel hinting causes black-on-black text rendering

Status in libcairo:
  Confirmed
Status in cairo package in Ubuntu:
  Triaged
Status in compiz package in Ubuntu:
  Invalid
Status in compiz-fusion-plugins-main package in Ubuntu:
  Invalid

Bug description:
  Binary package hint: libcairo2

  There is a long-standing problem (Gutsy, Hardy, Intrepid - possibly
  Jaunty too) with sub-pixel rendering which affects metacity or compiz
  composition (see the images attached to this bug) when VRGB is chosen
  as the sub-pixel format. Comment #15 by MoMaT demonstrates a non-
  compiz scenario. My comments #2 and #10 demonstrate the issue with
  Compiz enabled.

  The underlying issue essentially seems to be: where should sub-pixel
  rendering should be done - in libcairo or in the font renderer
  (FreeType in this case) ?

  There have been two versions of the Ubuntu patch in
  libcairo/libcairo2. Reports seem to suggest that both versions may be
  responsible for the VRGB problem (however, that supposition needs
  checking - see Bob McElrath's comment #19).

  We need to be aware that libcairo (libcairo 1.5.4 in Universe) and
  libcairo2 (cairo 1.6.0 in Main) are similarly patched and will need
  similar fixes.

To manage notifications about this bug go to:
https://bugs.launchpad.net/libcairo/+bug/145604/+subscriptions