Pango

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For other uses, see Pango (disambiguation).
Pango
Παν語
Pango name written as intended
Original author(s) Owen Taylor[1]
Raph Levien
Developer(s) Behdad Esfahbod
Initial release 11 July 1999 (1999-07-11)[2]
Stable release

1.36.3 (March 18, 2014; 3 months ago (2014-03-18)) [±]

[3]
Operating system Unix-like, Microsoft Windows, Other
Type Software development library
License LGPL
Website www.pango.org

Pango (Παν語) is a text layout engine library which works with HarfBuzz shaping engine for displaying multi-language text.[4] Full-function rendering of text and cross-platform support is had when Pango is used with platform APIs or 3rd party libraries, such as Uniscribe and FreeType, as text rendering backends. Pango-processed text will appear similar under different operating systems.[clarification needed]

Pango is a special-purpose library for text and not a general-purpose graphics rendering library such as Cairo, with which Pango can be used. Indeed, the Cairo documentation recommends Pango be used to "render" text rather than Cairo for all but the simplest text "rendering".

The name pango comes from Greek pan (παν, "all") and Japanese go (語, "language").[5]

Support for OpenType features[edit]

Default rendering above, localized Romanian rendering below.

Pango 1.17 and newer support the locl script tag that allows alternate glyphs to be used for the same Unicode code point. Assuming you have Verdana version 5.01 installed, which supports the locl feature for the latn/ROM (Romanian) script, a quick demonstration (on Linux) is:

for lang in en ro; do pango-view \
 --font="Verdana 64" \
 --text "şţ vs. șț in $lang" \
 --language=$lang; done

For an explanation of the substitutions rules for Romanian, see this discussion.

Setting the locale via the POSIX environment variable, e.g. LANG=ro_RO.UTF-8 will also cause Pango to use locl font feature. Finally, you can change the language on the fly in the same text using Pango markup, e.g.:

pango-view \
 --font="Verdana 24" \
 --markup \
 --text 'In the same text: <span lang="en">şţ</span>(en) and <span lang="ro">şţ</span>(ro).'

The official showcase of Pango's script-aware features is here.

Major users[edit]

Pango has been integrated into most Linux distributions. The GTK+ UI toolkit uses Pango for all of its text rendering. The Linux versions of the Mozilla Firefox web browser and Mozilla Thunderbird mail client use Pango for text rendering.

History[edit]

In January 2000 the merger of the GScript and GnomeText projects was named Pango.[6][7][8][9][10][11]

Pango version 1.0.0 was released 11 March 2002.[12][13]

See also[edit]

  • HarfBuzz (Text layout and shaping library and engine)
  • Uniscribe (Windows multilingual text rendering engine)
  • WorldScript (Old Macintosh multilingual text rendering engine)
  • Core Text (modern multilingual text rendering engine introduced in Mac OS X 10.5)
  • Graphite (multiplatform open source smart-font renderer)
  • FontForge a typeface (font) editor program

References[edit]

  1. ^ Interview: Red Hat's Owen Taylor on GTK+, also known for his contributions on Pango., by Eugenia Loli, 19th Dec 2003
  2. ^ Pango, Made version 0.2, Owen Taylor, redhat.com
  3. ^ "Pango (Recent releases)". Retrieved 2014-03-18. 
  4. ^ "Pango website". Retrieved 7 July 2011. 
  5. ^ "The Pango connection: Part 1". Archived from the original on 27 June 2009. Retrieved 7 July 2011. 
  6. ^ Pango - Status - 14 January 2000, Owen Taylor, Redhat
  7. ^ GNOMEs in Paris: A Report from GUADEC, The most impressive part of their presentation was the discussion on Pango (the result of the GScript and GnomeText merger), 2000/03/21, By Chuck Toporek - O'Reilly Media
  8. ^ Pango proposal, rev 0.1, Raph Levien, 28 Jul 1999
  9. ^ GScript - Unicode and Complex Text Processing, The GScript project has been merged with the GnomeText project. For information about the result, named Pango, see: http://www.pango.org If you have trouble accessing that site, there is a mirror here. By Owen Taylor
  10. ^ Gnome-Text API documentation, Raph Levien, 10 Jul 1999, Owen Taylor is working on gscript, which has some overlap with the functions described in this interface. We're workingon unifying the two api's as much as possible.
  11. ^ GNOME Developer's Interview Follow-up, by Ali Abdin, 27 December ????, Pango (which is the code name for a merger of my Gscript project and Raph Levien's GnomeText project) is a modular set of libraries for doing layout and rendering of international text. It's a bit similar to Microsoft's Uniscript or Apple's ATSUI.
  12. ^ Archive copy at the Wayback Machine, Pango 1.0.0 released
  13. ^ GTK+ user interface libraries, version 2.0

External links[edit]