FreeType

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FreeType
FreeType-logo.png
Developer(s) David Turner, Robert Wilhelm, Werner Lemberg[1][2] and FreeType contributors
Initial release 1996; 18 years ago (1996)[3]
Stable release 2.5.3 / March 8, 2014; 8 months ago (2014-03-08)[4]
Written in C
Operating system Cross-platform
Type Software development library: Font rasterization
License GNU General Public License / FreeType License
Website freetype.org

FreeType is a software development library, available in source and binary forms, used to render text on to bitmaps and provides support for other font-related operations. As such, the source code is an implementation of a font rasterization engine. A number of font formats, including TrueType, Type 1, and OpenType, are supported.[5] The current version "is designed to be small, efficient, highly customizable, and portable while capable of producing high-quality output (glyph images)."[5]

Features[edit]

Hinting[edit]

TrueType
TrueType bytecode interpreter is enabled by default in 2.4.0.[6] TrueType subpixel hinting support is implemented in 2.4.11.[7]
PostScript
New CFF parsing and hinting engine by Dave Arnold was introduced in 2.4.12.[8] 2.5.0.1 enables this by default.
Auto-hinter
auto-hinter was replaced by auto-fitter in FreeType 2.1.10.[9] An new algorithm for CJK fonts was introduced in FreeType 2.2, based on Akito Hirai's patch.[10]

File formats[edit]

Adobe's new SING Glyphlet format was introduced in FreeType 2.2.[10] Bit 1 in the "head" table of TrueType fonts is supported in FreeType 2.2.[10] Support for SFNT cmap 13 table format is added in 2.3.10.[11] Support for OpenType collections and CFF fonts within an SFNT wrapper are added in 2.4.11.[7]

PostScript
track kerning support for AFM file is added in FreeType 2.2.[10]

History[12][13][edit]

FreeType 1 had support for only the TrueType font format but it included an extension to support OpenType text layout features.

FreeType 2 brought support for more font formats and evolved source code which the developers stated was "simpler and more powerful".[14] FreeType 2 is not backward-compatible with FreeType 1 but the developers state that moving from FreeType 1 to FreeType 2 poses little difficulty.[14]

As text layout processing was not an objective of FreeType 2, however, the OpenType text layout functionality of FreeType 1 was removed in FreeType 2. A very evolved form of the OpenType text layout functionality of FreeType 1 is used in the Pango text layout library. The HarfBuzz project is further evolving that functionality with a complete rewrite offered as a standalone library with a less restrictive license than Pango's license.[15]

Users[edit]

Android
FreeType is used as font renderer in Android.[16]
Apple
Apple uses FreeType in iOS[16] and OS X[17] next to Apple Advanced Typography.
Java
In 2007, Sun Microsystems switched from using a proprietary font rasterizer to using FreeType in the OpenJDK Java development kit.[18]
PlayStation
Sony ships FreeType with its PlayStation 3,[19] PlayStation 4,[20] and PlayStation Vita[21] consoles.

Other users[edit]

MacType config windows

As well as being used by the major free software desktop systems, FreeType has been used as a rasterization engine for modern video games,[22][23] and Opera for the Wii.[24] The gdipp[25] and MacType[26] projects replace the Windows system font renderer with FreeType.

Patent conflicts[edit]

Some open source projects such as FreeBSD or Linux, have included FreeType with font hinting functionality disabled or degraded to avoid the issue of software patents held by Apple Incorporated.[27]

Since May 2010, all conflicting software patents related to font hinting expired,[27] allowing FreeType's TrueType font hinter to be used in open source. Many of the operating systems which disabled the renderer now give the user the option to enable it. In Fedora, freetype-freeworld was switched from the proprietary yum repository to the free repository.[28]

Microsoft's patent for ClearType includes a specific color filtering algorithm for use in LCD display subpixel rendering. FreeType’s subpixel rendering implementation is thus currently disabled by default.[27]

See also[edit]

  • HarfBuzz, a library for shaping of Unicode text.
  • Pango, a multilingual text rendering engine
  • FontForge, a typeface (font) editor program
  • AltNETType, a FreeType port to C#

References[edit]

  1. ^ "Interview with David Turner of Freetype". OSNews. June 28, 2007. Retrieved March 31, 2011. 
  2. ^ "The FreeType Project LICENSE" (text). FreeType. January 27, 2006. Retrieved March 31, 2011. 
  3. ^ "FreeType History". 2013-07-02. Retrieved 2014-08-06. 
  4. ^ "FreeType 2.5.4". 2014-03-08. Retrieved 2014-03-08. 
  5. ^ a b "FreeType 2 Overview". FreeType 2. SourceForge, Inc. July 4, 2010. Features. Retrieved March 31, 2011. 
  6. ^ "CHANGES BETWEEN 2.3.12 and 2.4.0". Sourceforge.net. 2010-07-12. Retrieved 2014-04-04. 
  7. ^ a b "CHANGES BETWEEN 2.4.10 and 2.4.11". Sourceforge.net. 2012-12-20. Retrieved 2014-04-04. 
  8. ^ "CHANGES BETWEEN 2.4.11 and 2.4.12". Sourceforge.net. 2013-05-08. Retrieved 2014-04-04. 
  9. ^ "Announcing FreeType 2.1.10". Lists.nongnu.org. 2005-06-15. Retrieved 2014-04-04. 
  10. ^ a b c d "FreeType version 2.2.1 released". Lists.nongnu.org. Retrieved 2014-04-04. 
  11. ^ "CHANGES BETWEEN 2.3.10 and 2.3.9". Sourceforge.net. Retrieved 2014-04-04. 
  12. ^ [1][dead link]
  13. ^ "What are the differences between FreeType 1.x and FreeType 2 ?". Experts123.com. Retrieved 2014-04-04. 
  14. ^ a b "FreeType 2 FAQ". FreeType 2. Retrieved July 26, 2011. 
  15. ^ "HarfBuzz". Freedesktop.org. Retrieved 2014-04-04. 
  16. ^ a b "Got CFF?". Google Open Source Blog. Retrieved 2014-04-04. 
  17. ^ "About the security content of OS X Lion v10.7.3 and Security Update 2012-001". Support.apple.com. 2012-05-31. Retrieved 2014-04-04. 
  18. ^ "Font Scaler". Retrieved 4 April 2014. 
  19. ^ "PlayStation®3 License". Scei.co.jp. Retrieved 2014-04-04. 
  20. ^ "Open Source Software used in PlayStation®4". Scei.co.jp. Retrieved 2014-04-04. 
  21. ^ "Open Source Software used in PlayStation®Vita". Scei.co.jp. Retrieved 2014-04-04. 
  22. ^ Games company Relic Entertainment has used FreeType for their games Dawn of War and Company of Heroes, as can be seen in the credits on the loading screens.
  23. ^ FreeType has also been implemented in the American Girl games for the PC such as A Treehouse of My Own and Julie Saves The Eagles.
  24. ^ Opera 9 for the Wii console uses FreeType, as can be seen by looking at the "Third-party information" page which can be found on the Wii via: Internet Channel > Operations Guide > About > Opera 9 for Wii — Third-party information
  25. ^ "gdipp". Retrieved 4 August 2014. 
  26. ^ "MacType". Retrieved 4 April 2014. 
  27. ^ a b c "FreeType and Patents". FreeType. SourceForge, Inc. July 4, 2010. Retrieved March 31, 2011. 
  28. ^ "RepoView: RPM Fusion (Fedora - free) development Source RPM Packages". Download1.rpmfusion.org. 2014-03-11. Retrieved 2014-04-04. 

External links[edit]