gfx/graphite2/README.md

   1 # Graphite engine
   2
   3 ## Project CI status
   4 | OS      | Intel 64 bit | Intel 32 bit | Arm 32 bit |
   5 |---------|:------------:|:------------:|:----------:|
   6 | Linux   | [![Build Status](http://build.palaso.org/app/rest/builds/buildType:bt124/statusIcon)](http://build.palaso.org/viewType.html?buildTypeId=bt124&guest=1) | [![Build Status](http://build.palaso.org/app/rest/builds/buildType:bt123/statusIcon)](http://build.palaso.org/viewType.html?buildTypeId=bt123&guest=1) | [![Build Status](http://build.palaso.org/app/rest/builds/buildType:Graphite_Linux32bitArm/statusIcon)](http://build.palaso.org/viewType.html?buildTypeId=Graphite_Linux32bitArm&guest=1) |
   7 | Windows | [![Build Status](http://build.palaso.org/app/rest/builds/buildType:Graphite_Windows64bit/statusIcon)](http://build.palaso.org/viewType.html?buildTypeId=Graphite_Windows64bit&guest=1) | [![Build Status](http://build.palaso.org/app/rest/builds/buildType:bt91/statusIcon)](http://build.palaso.org/viewType.html?buildTypeId=bt91&guest=1)| |
   8
   9 ## What is Graphite?
  10
  11 Graphite is a system that can be used to create “smart fonts” capable of displaying writing systems with various complex behaviors. A smart font contains not only letter shapes but also additional instructions indicating how to combine and position the letters in complex ways.
  12
  13 Graphite was primarily developed to provide the flexibility needed for minority languages which often need to be written according to slightly different rules than well-known languages that use the same script.
  14
  15 Examples of complex script behaviors Graphite can handle include:
  16
  17 * contextual shaping
  18 * ligatures
  19 * reordering
  20 * split glyphs
  21 * bidirectionality
  22 * stacking diacritics
  23 * complex positioning
  24 * shape aware kerning
  25 * automatic diacritic collision avoidance
  26
  27 See [examples of scripts with complex rendering](http://scripts.sil.org/CmplxRndExamples).
  28
  29 ## Graphite system overview
  30 The Graphite system consists of:
  31
  32 * A rule-based programming language [Graphite Description Language](http://scripts.sil.org/cms/scripts/page.php?site_id=projects&item_id=graphite_devFont#gdl) (GDL) that can be used to describe the behavior of a writing system
  33 * A compiler for that language
  34 * A rendering engine that can serve as the layout component of a text-processing application
  35
  36 Graphite renders TrueType fonts that have been extended by means of compiling a GDL program.
  37
  38 Further technical information is available on the [Graphite technical overview](http://scripts.sil.org/cms/scripts/page.php?site_id=projects&item_id=graphite_techAbout) page.