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 <title>FreeType 2 Introduction</title>
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 <font size=1>http://www.freetype.org</font><p>

 <center>
   <a href="freetype.html">
   <img src="image/freetype.jpg" width=550 height=105 alt="The FreeType Project" border=0></a>
   <h1>An Introduction to FreeType 2</h1>
 </center>

 <center><table width=750 cellspacing=10 cellpadding=30><tr><td>
 <hr><p>

 DOCUMENT INDEX:<br>
 <ul>
   <li><a href="#what">What is FreeType 2 ?</a>
   <li><a href="#features">Features</a>
   <li><a href="#requirements">Requirements</a>
   <li><a href="#patents">Patents issues</a>
 </ul><p>


 <hr><p>

 <table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
 <h2 align=center><a name="what">What is FreeType 2 ?</h2>
 </td></tr><tr><td>

 <p>The FreeType project is a team of volunteers who develop free, portable
 and high-quality software solutions for digital typography. We specifically
 target embedded systems and focus on bringing small, efficient and
 ubiquitous products.</p>

 <p>the FreeType 2 library is our new software font engine. It has been
    designed to provide the following important features:</p>

   <ul>
   <li><p>
     <b>A universal and simple API to manage font files:</b><br>
     <ul>
       <p>The FreeType 2 API is simple and easy to use. It supports both
          bitmapped and scalable fonts and is well-suited to manage font
 	 files of all formats. Unlike other font libraries, FreeType 2
 	 returns and manages outline font data (images & metrics).</p>
    </ul>
    </p></li>

   <li><p>
     <b>Support for several font formats through loadable modules:</b><br>
     <ul>
       <p>FreeType 2 uses <em>"font drivers"</em>. Each driver is a loadable
          module used to support one specific font format. Each driver can also
 	 provide specific extensions used to access format-specific features of
 	 the font.</p>
     </ul>
   </p></li>


   <li><p>
     <b>High-quality anti-aliasing:</b><br>
     <ul>
       <p>FreeType 2 produces etremely smooth outlines at small sizes, with its new
          anti-aliasing renderer, which produces bitmaps with 256-levels of gray.
 	 It uses a new algorithm that has been specifically designed to render
 	 small complex shapes (like glyphs) at high speed. Indeed, it's even
 	 faster than the monochrome renderer for small character sizes (under
 	 20 pixels) !!
       </p>
     </ul>


  <li><b>High portability & performance:</b><br>
      <ul>
        <p>The FreeType 2 source code is written in ANSI C and runs on any
           platform with a compliant compiler. Client applications can
 	  provide their own memory manager or input stream to the library
 	  (which means that font files can come from any place: disk,
 	  memory, compressed file, network, etc..).
        </p>
      </ul>

   </ul>

   <p>Note that <em>the beta of FreeType 2 is available <b>now</b></em>. For more
   info, check our <a href="download.html">Download page</a> or see the source
   and its diffs through our <a href="cgi-bin/cvsweb.cgi">CVS Web interface</a>.
   </p>
 </ul>

 </td></tr></table>

 <table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
 <h2 align=center><a name="features">Features</h2>
 </td></tr><tr><td>

 <h3>Supported font formats</h3>

 <p>FreeType 2 readily supports the following font formats:</p>

 <ul>
   <li>TrueType files (.ttf) and collections (.ttc)</li>
   <li>Type 1 font files both in ASCII (.pfa) or binary (.pfb) format</li>
   <li>Type 1 Multiple Master fonts. The FreeType 2 API also provides
       routines to manage design instances easily</li>
   <li>Type 1 CID-keyed fonts</li>
   <li>OpenType/CFF (.otf) fonts</li>
   <li>CFF/Type 2 fonts</li>
   <li>Adobe CEF fonts (.cef), used to embed fonts in SVG documents
       with the Adobe SVG viewer plugin.</li>
   <li>Windows FNT/FON bitmap fonts</li>
 </ul>

 <p>Note that Apple's TrueType GX fonts are supported as normal TTFs,
    (the advanced tables are ignored).</p>

 <p>Besides, it's possible to add support for new font formats by providing
    a specific <em>font driver</em> module. Modules can be added either at
    build time (when recompiling the library), or at <em>run-time</em>;
    this allows, for example, applications to register their own
    font driver to support program-specific formats.</p>


 <h3>Patent-free automatic hinter</h3>

 <p>TrueType fonts are normally renderered (hinted) with the help of a
    specific bytecode where the behaviour of a few opcodes is patented by
    Apple. We're currently in contact with Apple to discuss the importance
    of such patents and their use in open source projects like FreeType.
    </p>

 <p>In the meantime, we have developped our own alternative technology that
    is capable of automatically hinting scalable glyph images. It is
    now part of the FreeType 2 source tree as the "autohint" module,
    and is used to hint glyphs when the bytecode interpreter is disabled
    (through a configuration macro when building the engine). Note that
    the auto-hinter is also used to handle glyphs in other formats like
    CFF and Type 1.</p>

 <p>The auto-hinter provides pretty good results (in some cases, it even
    significantly improves the output of poorly hinted fonts) but we'll
    continue to improve it with each new release of FreeType to achieve
    the highest possible quality.</p>


 <h3>Modular design:</h3>

 <p>The design of FreeType 2 is extremely modular as most features are
    supported through optional modules. This means it's easily possible to
    only compile the features you need. As each module is between
    10 and 20 Kb in size, it's possible to build a bare-bones
    font engine that supports anti-aliasing in about 30 Kb !!</p>

 <p>Configuration is performed by  modifications of only two header
    files (one to select global features, another one to select modules)
    and don't need tweaking of source code. Note that it is however
    possible to provide your own implementation of certain components.</p>

 <p>For example, when building on Unix, the engine will automatically
    use memory-mapped files when available on the target platform,
    thus significantly increasing font file i/o.</p>


 <p>Due to its very flexible design, it is possible to add, remove and
    upgrade modules at run-time.</p>


 <h3>Advanced glyph management</h3>

 <p>The API comes with a standard extension used to extract individual
    glyph images from font files. These images can be bitmaps, scalable
    bezier outlines or even anything else. (e.g. bi-color or metafont
    glyphs, as long as they're supported by a module).</p>

 <p>Each scalable glyph image can be transformed, measured and
    rendered into a monochrome or anti-aliased bitmaps easily
    through a uniform interface.

    This allows client applications to easily cache glyphs or
    perform text rendering effects with minimal difficulty
    (look at the FreeType 2 Tutorial to see how to render
     rotated text with very few lines of code).
 </p>


 <h3>Advanced font access</h3>

 <p>The FreeType 2 API is useful to retrieve advanced information from
    various fonts:</p>

 <ul>
   <li>vertical metrics are available whenever found in the font file</li>

   <li>kerning distances are available when found in the font file. It
       is also possible to "attach" a given additional file to a given
       font face. This is useful to load kerning distances from an
       .afm file into a Type 1 face for example.</li>

   <li>provides ASCII glyph names whenever available in the font
       (TrueType, OpenType, Type1, etc..)</li>

   <li>provides access to important tables for SFNT-based font formats
       (i.e. TrueType, OpenType, CEF, etc..), like the name table,
       font header, maximum profile, etc...</li>

   <li>automatic synthesis of Unicode-based character maps for
       those fonts or formats that do not provide one. This is
       extremely useful with Type 1 fonts which are normally
       limited to a stupid 256-characters encoding.</li>
 </ul>


 <h3>Simple & clean API</h3>

 <p>The FreeType 2 high-level API is simple and straightforward, as it
    has been specifically designed to make the most commmon font operations
    easy</p>

 <p>As a comparison, the number of function calls needed to perform a
    the tasks of font face creation/opening and glyph loading/rendering
    has been reduced by a factor of 4 !!</p>

 <p>The API is also independent of any font-format specific issue, though
    it provides standard extensions to access format-specific tables and
    information. More extensions can also be easily added through new
    modules</p>


 <h3>Robust & Portable code</h3>

 <p>Because it is written in industry-standard ANSI C, FreeType 2 compiles
    on all platforms with a compliant compiler. Because the default build
    only relies on the C library, it is free of any system-specific
    dependencies, even if it is possible to "enhance" certain components
    by providing a specific implementation.</p>

 <p>The code doesn't use global or static variables. Client applications
    can provide their own memory manager. Font files can be read from
    a disk file, memory, or through a client-provided input stream. This
    allows to support compressed font files, remote fonts, fonts embedded
    in other streams (e.g. Type42 fonts), etc..</p>

 <p>An advanced i/o sub-system is used to optimise file access, as well
    as reduce memory usage of the library when the file is memory-based
    ( ROM, RAM, memory-mapped ).</p>


 <h3>Open Source & Vendor Independence</h3>

 <p>Finally, FreeType 2 is released under its own BSD-like open source
    license, one of the less restricting licenses available, and this
    means that:</p>

 <ul>
   <li><p>
     It can be included in all kinds of products, be they proprietary
     or not.
   </p></li>

   <li><p>
     As any module can be added or replaced anytime, any third party
     vendor  has the ability to provide its own set of modules (under
     its own license) in order to support proprietary font formats or
     more advanced features (e.g. a new auto-hinter, or a new
     anti-aliasing renderer for LCDs or TV screens).
   </p></li>
 </ul>

 <p>One could even imagine an application using the FreeType 2 API with
    a "wrapper" module used to access system-specific fonts (like through
    the Windows GDI). This would mean native font support with more portable
    application code (as simply changing the wrapper module would be required
    to port the application to another system).</p>

 </td></tr></table>

 <table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
 <h2 align=center><a name="requirements">Requirements</h2>
 </td></tr><tr><td>

 <p>FreeType 2 is written in ANSI&nbsp;C and should compile with no problems
    on a great variety of platforms. We have taken care of removing all
    compilation warnings from major compliant compilers. Detailed compilation
    instructions are provided in the software archive.</p>

 <p>This version of the library has been succesfully compiled and run
    under the following systems: Dos, OS/2, Windows, Macintosh, Unix
    (including the 64-bits DEC Unix, a.k.a. "True64"). You should not
    encounter major problems compiling it on any other kind of platform.
    In all cases, contact us if you do.</p>

 <p>Note that a small set of demonstration programs is also separately
    available. They include a tiny graphics sub-system that is used to
    display and show-off the library's capabilities on the following
    platforms: X11, MacOS, OS/2 & Windows.</p>

 <p>Please visit our <a href="http://www.freetype.org/download.html">
    Download section</a> to access the software archives.</p>

 </ul>

 </td></tr></table>

 <table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
 <h2 align=center><a name="patents">Patents issues</h2>
 </td></tr><tr><td>

 <p>The FreeType 2 source code includes a TrueType bytecode interpreter that
    is covered by the Apple patents. However, this piece of code is never
    compiled by default in this release (unlike in previous betas) making
    a default build of the library <em>entirely patent-free !!</em></p>

 <p>Note that in order to compile the interpreter, one needs to define
    the configuration macro <tt><b>TT_CONFIG_OPTION_BYTECODE_INTERPRETER</b></tt> configuration
    macro in the file "<tt>ftoption.h</tt>". More details are available in
    the software archive. Note that the use of the interpreter is normally
    protected by US, UK and French patents. In the event you'd absolutely
    need it, you may have to <a href="mailto:patents@apple.org">contact
    Apple legal department</a> for licensing conditions, depending on your
    location and the places you distribute/sell your products.</p>

 <p>Please do not ask us any detailed information regarding licensing, as
    we're still discussing with Apple this issue, we're unable to inform
    the public of what's currently going on..</p>

 </td></tr></table>

 <hr>
 <p>
 <a href="index.html">Back to FreeType homepage</a><p>

 </td></tr></table>
 </body>
 </html>
	<html>
	<head>
	<title>FreeType 2 Introduction</title>
	<basefont face="Georgia, Arial, Helvetica, Geneva">
	<style content="text/css">
	P { text-align=justify }
	H1 { text-align=center }
	H2 { text-align=center }
	LI { text-align=justify }
	</style>
	</head>

	<body text="#000000"
	bgcolor="#FFFFFF"
	link="#0000EF"
	vlink="#51188E"
	alink="#FF0000">


	<font size=1>http://www.freetype.org</font><p>

	<center>
	<a href="freetype.html">
	<img src="image/freetype.jpg" width=550 height=105 alt="The FreeType Project" border=0></a>
	<h1>An Introduction to FreeType 2</h1>
	</center>

	<center><table width=750 cellspacing=10 cellpadding=30><tr><td>
	<hr><p>

	DOCUMENT INDEX:<br>
	<ul>
	<li><a href="#what">What is FreeType 2 ?</a>
	<li><a href="#features">Features</a>
	<li><a href="#requirements">Requirements</a>
	<li><a href="#patents">Patents issues</a>
	</ul><p>


	<hr><p>

	<table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
	<h2 align=center><a name="what">What is FreeType 2 ?</h2>
	</td></tr><tr><td>

	<p>The FreeType project is a team of volunteers who develop free, portable
	and high-quality software solutions for digital typography. We specifically
	target embedded systems and focus on bringing small, efficient and
	ubiquitous products.</p>

	<p>the FreeType 2 library is our new software font engine. It has been
	designed to provide the following important features:</p>

	<ul>
	<li><p>
	<b>A universal and simple API to manage font files:</b><br>
	<ul>
	<p>The FreeType 2 API is simple and easy to use. It supports both
	bitmapped and scalable fonts and is well-suited to manage font
	files of all formats. Unlike other font libraries, FreeType 2
	returns and manages outline font data (images & metrics).</p>
	</ul>
	</p></li>

	<li><p>
	<b>Support for several font formats through loadable modules:</b><br>
	<ul>
	<p>FreeType 2 uses <em>"font drivers"</em>. Each driver is a loadable
	module used to support one specific font format. Each driver can also
	provide specific extensions used to access format-specific features of
	the font.</p>
	</ul>
	</p></li>


	<li><p>
	<b>High-quality anti-aliasing:</b><br>
	<ul>
	<p>FreeType 2 produces etremely smooth outlines at small sizes, with its new
	anti-aliasing renderer, which produces bitmaps with 256-levels of gray.
	It uses a new algorithm that has been specifically designed to render
	small complex shapes (like glyphs) at high speed. Indeed, it's even
	faster than the monochrome renderer for small character sizes (under
	20 pixels) !!
	</p>
	</ul>


	<li><b>High portability & performance:</b><br>
	<ul>
	<p>The FreeType 2 source code is written in ANSI C and runs on any
	platform with a compliant compiler. Client applications can
	provide their own memory manager or input stream to the library
	(which means that font files can come from any place: disk,
	memory, compressed file, network, etc..).
	</p>
	</ul>

	</ul>

	<p>Note that <em>the beta of FreeType 2 is available <b>now</b></em>. For more
	info, check our <a href="download.html">Download page</a> or see the source
	and its diffs through our <a href="cgi-bin/cvsweb.cgi">CVS Web interface</a>.
	</p>
	</ul>

	</td></tr></table>

	<table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
	<h2 align=center><a name="features">Features</h2>
	</td></tr><tr><td>

	<h3>Supported font formats</h3>

	<p>FreeType 2 readily supports the following font formats:</p>

	<ul>
	<li>TrueType files (.ttf) and collections (.ttc)</li>
	<li>Type 1 font files both in ASCII (.pfa) or binary (.pfb) format</li>
	<li>Type 1 Multiple Master fonts. The FreeType 2 API also provides
	routines to manage design instances easily</li>
	<li>Type 1 CID-keyed fonts</li>
	<li>OpenType/CFF (.otf) fonts</li>
	<li>CFF/Type 2 fonts</li>
	<li>Adobe CEF fonts (.cef), used to embed fonts in SVG documents
	with the Adobe SVG viewer plugin.</li>
	<li>Windows FNT/FON bitmap fonts</li>
	</ul>

	<p>Note that Apple's TrueType GX fonts are supported as normal TTFs,
	(the advanced tables are ignored).</p>

	<p>Besides, it's possible to add support for new font formats by providing
	a specific <em>font driver</em> module. Modules can be added either at
	build time (when recompiling the library), or at <em>run-time</em>;
	this allows, for example, applications to register their own
	font driver to support program-specific formats.</p>


	<h3>Patent-free automatic hinter</h3>

	<p>TrueType fonts are normally renderered (hinted) with the help of a
	specific bytecode where the behaviour of a few opcodes is patented by
	Apple. We're currently in contact with Apple to discuss the importance
	of such patents and their use in open source projects like FreeType.
	</p>

	<p>In the meantime, we have developped our own alternative technology that
	is capable of automatically hinting scalable glyph images. It is
	now part of the FreeType 2 source tree as the "autohint" module,
	and is used to hint glyphs when the bytecode interpreter is disabled
	(through a configuration macro when building the engine). Note that
	the auto-hinter is also used to handle glyphs in other formats like
	CFF and Type 1.</p>

	<p>The auto-hinter provides pretty good results (in some cases, it even
	significantly improves the output of poorly hinted fonts) but we'll
	continue to improve it with each new release of FreeType to achieve
	the highest possible quality.</p>


	<h3>Modular design:</h3>

	<p>The design of FreeType 2 is extremely modular as most features are
	supported through optional modules. This means it's easily possible to
	only compile the features you need. As each module is between
	10 and 20 Kb in size, it's possible to build a bare-bones
	font engine that supports anti-aliasing in about 30 Kb !!</p>

	<p>Configuration is performed by modifications of only two header
	files (one to select global features, another one to select modules)
	and don't need tweaking of source code. Note that it is however
	possible to provide your own implementation of certain components.</p>

	<p>For example, when building on Unix, the engine will automatically
	use memory-mapped files when available on the target platform,
	thus significantly increasing font file i/o.</p>


	<p>Due to its very flexible design, it is possible to add, remove and
	upgrade modules at run-time.</p>



	<h3>Advanced glyph management</h3>

	<p>The API comes with a standard extension used to extract individual
	glyph images from font files. These images can be bitmaps, scalable
	bezier outlines or even anything else. (e.g. bi-color or metafont
	glyphs, as long as they're supported by a module).</p>

	<p>Each scalable glyph image can be transformed, measured and
	rendered into a monochrome or anti-aliased bitmaps easily
	through a uniform interface.

	This allows client applications to easily cache glyphs or
	perform text rendering effects with minimal difficulty
	(look at the FreeType 2 Tutorial to see how to render
	rotated text with very few lines of code).
	</p>



	<h3>Advanced font access</h3>

	<p>The FreeType 2 API is useful to retrieve advanced information from
	various fonts:</p>

	<ul>
	<li>vertical metrics are available whenever found in the font file</li>

	<li>kerning distances are available when found in the font file. It
	is also possible to "attach" a given additional file to a given
	font face. This is useful to load kerning distances from an
	.afm file into a Type 1 face for example.</li>

	<li>provides ASCII glyph names whenever available in the font
	(TrueType, OpenType, Type1, etc..)</li>

	<li>provides access to important tables for SFNT-based font formats
	(i.e. TrueType, OpenType, CEF, etc..), like the name table,
	font header, maximum profile, etc...</li>

	<li>automatic synthesis of Unicode-based character maps for
	those fonts or formats that do not provide one. This is
	extremely useful with Type 1 fonts which are normally
	limited to a stupid 256-characters encoding.</li>
	</ul>


	<h3>Simple & clean API</h3>

	<p>The FreeType 2 high-level API is simple and straightforward, as it
	has been specifically designed to make the most commmon font operations
	easy</p>

	<p>As a comparison, the number of function calls needed to perform a
	the tasks of font face creation/opening and glyph loading/rendering
	has been reduced by a factor of 4 !!</p>

	<p>The API is also independent of any font-format specific issue, though
	it provides standard extensions to access format-specific tables and
	information. More extensions can also be easily added through new
	modules</p>


	<h3>Robust & Portable code</h3>

	<p>Because it is written in industry-standard ANSI C, FreeType 2 compiles
	on all platforms with a compliant compiler. Because the default build
	only relies on the C library, it is free of any system-specific
	dependencies, even if it is possible to "enhance" certain components
	by providing a specific implementation.</p>

	<p>The code doesn't use global or static variables. Client applications
	can provide their own memory manager. Font files can be read from
	a disk file, memory, or through a client-provided input stream. This
	allows to support compressed font files, remote fonts, fonts embedded
	in other streams (e.g. Type42 fonts), etc..</p>

	<p>An advanced i/o sub-system is used to optimise file access, as well
	as reduce memory usage of the library when the file is memory-based
	( ROM, RAM, memory-mapped ).</p>


	<h3>Open Source & Vendor Independence</h3>

	<p>Finally, FreeType 2 is released under its own BSD-like open source
	license, one of the less restricting licenses available, and this
	means that:</p>

	<ul>
	<li><p>
	It can be included in all kinds of products, be they proprietary
	or not.
	</p></li>

	<li><p>
	As any module can be added or replaced anytime, any third party
	vendor has the ability to provide its own set of modules (under
	its own license) in order to support proprietary font formats or
	more advanced features (e.g. a new auto-hinter, or a new
	anti-aliasing renderer for LCDs or TV screens).
	</p></li>
	</ul>

	<p>One could even imagine an application using the FreeType 2 API with
	a "wrapper" module used to access system-specific fonts (like through
	the Windows GDI). This would mean native font support with more portable
	application code (as simply changing the wrapper module would be required
	to port the application to another system).</p>

	</td></tr></table>

	<table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
	<h2 align=center><a name="requirements">Requirements</h2>
	</td></tr><tr><td>

	<p>FreeType 2 is written in ANSI C and should compile with no problems
	on a great variety of platforms. We have taken care of removing all
	compilation warnings from major compliant compilers. Detailed compilation
	instructions are provided in the software archive.</p>

	<p>This version of the library has been succesfully compiled and run
	under the following systems: Dos, OS/2, Windows, Macintosh, Unix
	(including the 64-bits DEC Unix, a.k.a. "True64"). You should not
	encounter major problems compiling it on any other kind of platform.
	In all cases, contact us if you do.</p>

	<p>Note that a small set of demonstration programs is also separately
	available. They include a tiny graphics sub-system that is used to
	display and show-off the library's capabilities on the following
	platforms: X11, MacOS, OS/2 & Windows.</p>

	<p>Please visit our <a href="http://www.freetype.org/download.html">
	Download section</a> to access the software archives.</p>

	</ul>

	</td></tr></table>

	<table width="100%" cellspacing=5><tr bgcolor="#CCCCEE"><td>
	<h2 align=center><a name="patents">Patents issues</h2>
	</td></tr><tr><td>

	<p>The FreeType 2 source code includes a TrueType bytecode interpreter that
	is covered by the Apple patents. However, this piece of code is never
	compiled by default in this release (unlike in previous betas) making
	a default build of the library <em>entirely patent-free !!</em></p>

	<p>Note that in order to compile the interpreter, one needs to define
	the configuration macro <tt><b>TT_CONFIG_OPTION_BYTECODE_INTERPRETER</b></tt> configuration
	macro in the file "<tt>ftoption.h</tt>". More details are available in
	the software archive. Note that the use of the interpreter is normally
	protected by US, UK and French patents. In the event you'd absolutely
	need it, you may have to <a href="mailto:patents@apple.org">contact
	Apple legal department</a> for licensing conditions, depending on your
	location and the places you distribute/sell your products.</p>

	<p>Please do not ask us any detailed information regarding licensing, as
	we're still discussing with Apple this issue, we're unable to inform
	the public of what's currently going on..</p>

	</td></tr></table>

	<hr>
	<p>
	<a href="index.html">Back to FreeType homepage</a><p>

	</td></tr></table>
	</body>
	</html>