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<h1><a href="../../index.html">FreeType</a> Overview</h1>
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<div id="what-is-freetype">
<h2>What is FreeType?</h2>
<p>FreeType is a software font engine that is designed to
be small, efficient, highly customizable, and portable
while capable of producing high-quality output (glyph
images). It can be used in graphics libraries, display
servers, font conversion tools, text image generation
tools, and many other products as well.</p>
<p>Note that FreeType is a <em>font service</em> and doesn't
provide APIs to perform higher-level features like text
layout or graphics processing (e.g., colored text
rendering, ‘hollowing’, etc.). However, it
greatly simplifies these tasks by providing a simple, easy
to use, and uniform interface to access the content of
font files.</p>
<p>FreeType is released under two open-source licenses: our
own
BSD-like <a href="http://git.savannah.gnu.org/cgit/freetype/freetype2.git/tree/docs/FTL.TXT">FreeType
License</a> and
the <a href="http://git.savannah.gnu.org/cgit/freetype/freetype2.git/tree/docs/GPLv2.TXT">GNU
Public License, Version 2</a>. It can thus be used
by any kind of projects, be they proprietary or not.</p>
<p>Please note that ‘FreeType’ is also called
‘FreeType 2’, to distinguish it from the
old, deprecated ‘FreeType 1’ library, a
predecessor no longer maintained and supported.</p>
</div>
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<div id="features">
<h2>Features</h2>
<p>The following is a non-exhaustive list of features
provided by FreeType.</p>
<ul>
<li>
<p>FreeType provides a simple and easy-to-use API to
access font content in a uniform way, independently of
the file format. Additionally, some format-specific
APIs can be used to access special data in the font
file.</p>
</li>
<li>
<p>The design of FreeType is based on modules that can
be either linked statically to the library at compile
time, or loaded on demand at runtime. Modules are
used to support specific font formats, or even new
glyph image formats!</p>
</li>
<li>
<p>FreeType was written with embedded systems in mind.
This means that it doesn't use static writable data
(i.e., it can be run from ROM directly), and that
client applications can provide their own memory
manager and I/O stream implementation. The latter
allows you to easily read from ROM-based, compressed
or remote font files with the same API. Several
stream implementations can be used concurrently with a
single FreeType instance.</p>
<p>You can also reduce the size of the FreeType code by
only compiling the modules you need for your embedded
project or environment.</p>
</li>
<li>
<p>By default, FreeType supports the following font
formats.</p>
<ul>
<li>TrueType fonts (TTF) and TrueType collections
(TTC)</li>
<li>CFF fonts</li>
<li>WOFF fonts</li>
<li>OpenType fonts (OTF, both TrueType and CFF
variants) and OpenType collections (OTC)</li>
<li>Type 1 fonts (PFA and PFB)</li>
<li>CID-keyed Type 1 fonts</li>
<li>SFNT-based bitmap fonts, including color Emoji</li>
<li>X11 PCF fonts</li>
<li>Windows FNT fonts</li>
<li>BDF fonts (including anti-aliased ones)</li>
<li>PFR fonts</li>
<li>Type 42 fonts (limited support)</li>
</ul>
</li>
<li>
<p>From a given glyph outline, FreeType is capable of
producing a high-quality monochrome bitmap, or
anti-aliased pixmap, using 256 levels of
‘gray’.</p>
</li>
<li>
<p>FreeType supports all the character mappings defined
by the TrueType and OpenType specifications. It is
also capable of automatically synthetizing a Unicode
charmap from Type 1 fonts, avoiding painful
‘encoding translation’ problems common
with this format (of course, original encodings are
also available if necessary).</p>
</li>
<li>
<p>The FreeType core API provides simple functions to
access advanced information like glyph names or basic
kerning data.</p>
</li>
<li>
<p>A full-featured and efficient TrueType bytecode
interpreter, trying to match the results of the
Windows bytecode engine. There is also the
possibility to activate subpixel hinting
(a.k.a. <em>ClearType</em>, still under
development).</p>
</li>
<li>
<p>For those who don't need or want to use the bytecode
interpreter for TrueType fonts, we developed our
own <em>automatic hinter</em> module. It is also used
by other scalable formats.</p>
</li>
<li>
<p>Due to its modular design, it is easy to enhance the
library, providing additional format-specific
information through optional APIs (as an example, an
optional API is provided to retrieve SFNT tables from
TrueType and OpenType fonts).</p>
</li>
<li>
<p>FreeType provides its own caching subsystem. It can
be used to cache either face instances or glyph images
efficiently.</p>
</li>
<li>
<p>A bundle of demo programs demonstrate the usage of
FreeType; look for the
‘ft2demos-<i>x.x.x</i>’ archive (or
‘ftdmo<i>xxx</i>’ in case you are on a
Windows platform) at the locations
given <a href="../../download.html">here</a>.
‘<i>x.x.x</i>’ (or
‘<i>xxx</i>’) gives the version number,
for example ‘2.4.10’ or
‘2410’.</p>
</li>
</ul>
</div>
<!-- ************************************************** -->
<div id="requirements">
<h2>Requirements</h2>
<p>FreeType is written in industry-standard ANSI C and
should compile easily with any compliant C or C++
compiler. We have even taken great care to
eliminate <em>all warnings</em> when compiling with
popular compilers like gcc, Visual C++, and Borland
C++.</p>
<p>Apart from a standard ANSI C library, FreeType
doesn't have any external dependencies and can be compiled
and installed on its own on any kind of system. Some
modules <em>need</em> external libraries (e.g., for
handling fonts compressed with gzip or bz2), however, they
are optional and can be disabled.</p>
</div>
<!-- ************************************************** -->
<div id="patents">
<h2>Patent Issues</h2>
<p>All patents related to the TrueType bytecode interpreter
expired in May 2010. All patents related to the ClearType
color filtering model expired in August 2019.</p>
<p>More information regarding this topic is available at
our <a href="../../patents.html">patents page</a>.</p>
</div>
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<div class="updated">
<p>Last update: 17-Aug-2020</p>
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