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<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table>
<h1>FreeType-2.6.2 API Reference</h1>
<h1 id="base_interface">Base Interface</h1>
<h2>Synopsis</h2>
<table class="synopsis">
<tr><td><a href="#FT_Library">FT_Library</a></td><td><a href="#FT_Glyph_Metrics">FT_Glyph_Metrics</a></td><td><a href="#FT_LOAD_COLOR">FT_LOAD_COLOR</a></td></tr>
<tr><td><a href="#FT_Face">FT_Face</a></td><td><a href="#FT_SubGlyph">FT_SubGlyph</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_Size">FT_Size</a></td><td>&nbsp;</td><td><a href="#FT_LOAD_VERTICAL_LAYOUT">FT_LOAD_VERTICAL_LAYOUT</a></td></tr>
<tr><td><a href="#FT_GlyphSlot">FT_GlyphSlot</a></td><td><a href="#FT_Bitmap_Size">FT_Bitmap_Size</a></td><td><a href="#FT_LOAD_IGNORE_TRANSFORM">FT_LOAD_IGNORE_TRANSFORM</a></td></tr>
<tr><td><a href="#FT_CharMap">FT_CharMap</a></td><td>&nbsp;</td><td><a href="#FT_LOAD_FORCE_AUTOHINT">FT_LOAD_FORCE_AUTOHINT</a></td></tr>
<tr><td><a href="#FT_Encoding">FT_Encoding</a></td><td><a href="#FT_Init_FreeType">FT_Init_FreeType</a></td><td><a href="#FT_LOAD_NO_RECURSE">FT_LOAD_NO_RECURSE</a></td></tr>
<tr><td><a href="#FT_ENC_TAG">FT_ENC_TAG</a></td><td><a href="#FT_Done_FreeType">FT_Done_FreeType</a></td><td><a href="#FT_LOAD_PEDANTIC">FT_LOAD_PEDANTIC</a></td></tr>
<tr><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_FaceRec">FT_FaceRec</a></td><td><a href="#FT_New_Face">FT_New_Face</a></td><td><a href="#FT_LOAD_TARGET_NORMAL">FT_LOAD_TARGET_NORMAL</a></td></tr>
<tr><td>&nbsp;</td><td><a href="#FT_Done_Face">FT_Done_Face</a></td><td><a href="#FT_LOAD_TARGET_LIGHT">FT_LOAD_TARGET_LIGHT</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_SCALABLE">FT_FACE_FLAG_SCALABLE</a></td><td><a href="#FT_Reference_Face">FT_Reference_Face</a></td><td><a href="#FT_LOAD_TARGET_MONO">FT_LOAD_TARGET_MONO</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_FIXED_SIZES">FT_FACE_FLAG_FIXED_SIZES</a></td><td><a href="#FT_New_Memory_Face">FT_New_Memory_Face</a></td><td><a href="#FT_LOAD_TARGET_LCD">FT_LOAD_TARGET_LCD</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_FIXED_WIDTH">FT_FACE_FLAG_FIXED_WIDTH</a></td><td><a href="#FT_Open_Face">FT_Open_Face</a></td><td><a href="#FT_LOAD_TARGET_LCD_V">FT_LOAD_TARGET_LCD_V</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_HORIZONTAL">FT_FACE_FLAG_HORIZONTAL</a></td><td><a href="#FT_Open_Args">FT_Open_Args</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_FACE_FLAG_VERTICAL">FT_FACE_FLAG_VERTICAL</a></td><td><a href="#FT_Parameter">FT_Parameter</a></td><td><a href="#FT_LOAD_TARGET_MODE">FT_LOAD_TARGET_MODE</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_COLOR">FT_FACE_FLAG_COLOR</a></td><td><a href="#FT_Attach_File">FT_Attach_File</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_FACE_FLAG_SFNT">FT_FACE_FLAG_SFNT</a></td><td><a href="#FT_Attach_Stream">FT_Attach_Stream</a></td><td><a href="#FT_Render_Glyph">FT_Render_Glyph</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_CID_KEYED">FT_FACE_FLAG_CID_KEYED</a></td><td>&nbsp;</td><td><a href="#FT_Render_Mode">FT_Render_Mode</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_TRICKY">FT_FACE_FLAG_TRICKY</a></td><td><a href="#FT_Set_Char_Size">FT_Set_Char_Size</a></td><td><a href="#FT_Get_Kerning">FT_Get_Kerning</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_KERNING">FT_FACE_FLAG_KERNING</a></td><td><a href="#FT_Set_Pixel_Sizes">FT_Set_Pixel_Sizes</a></td><td><a href="#FT_Kerning_Mode">FT_Kerning_Mode</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_MULTIPLE_MASTERS">FT_FACE_FLAG_MULTIPLE_MASTERS</a></td><td><a href="#FT_Request_Size">FT_Request_Size</a></td><td><a href="#FT_Get_Track_Kerning">FT_Get_Track_Kerning</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_GLYPH_NAMES">FT_FACE_FLAG_GLYPH_NAMES</a></td><td><a href="#FT_Select_Size">FT_Select_Size</a></td><td><a href="#FT_Get_Glyph_Name">FT_Get_Glyph_Name</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_EXTERNAL_STREAM">FT_FACE_FLAG_EXTERNAL_STREAM</a></td><td><a href="#FT_Size_Request_Type">FT_Size_Request_Type</a></td><td><a href="#FT_Get_Postscript_Name">FT_Get_Postscript_Name</a></td></tr>
<tr><td><a href="#FT_FACE_FLAG_HINTER">FT_FACE_FLAG_HINTER</a></td><td><a href="#FT_Size_RequestRec">FT_Size_RequestRec</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_FACE_FLAG_TRICKY">FT_FACE_FLAG_TRICKY</a></td><td><a href="#FT_Size_Request">FT_Size_Request</a></td><td><a href="#FT_CharMapRec">FT_CharMapRec</a></td></tr>
<tr><td>&nbsp;</td><td><a href="#FT_Set_Transform">FT_Set_Transform</a></td><td><a href="#FT_Select_Charmap">FT_Select_Charmap</a></td></tr>
<tr><td><a href="#FT_HAS_HORIZONTAL">FT_HAS_HORIZONTAL</a></td><td><a href="#FT_Load_Glyph">FT_Load_Glyph</a></td><td><a href="#FT_Set_Charmap">FT_Set_Charmap</a></td></tr>
<tr><td><a href="#FT_HAS_VERTICAL">FT_HAS_VERTICAL</a></td><td><a href="#FT_Get_Char_Index">FT_Get_Char_Index</a></td><td><a href="#FT_Get_Charmap_Index">FT_Get_Charmap_Index</a></td></tr>
<tr><td><a href="#FT_HAS_KERNING">FT_HAS_KERNING</a></td><td><a href="#FT_Get_First_Char">FT_Get_First_Char</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_HAS_FIXED_SIZES">FT_HAS_FIXED_SIZES</a></td><td><a href="#FT_Get_Next_Char">FT_Get_Next_Char</a></td><td><a href="#FT_Get_FSType_Flags">FT_Get_FSType_Flags</a></td></tr>
<tr><td><a href="#FT_HAS_GLYPH_NAMES">FT_HAS_GLYPH_NAMES</a></td><td><a href="#FT_Get_Name_Index">FT_Get_Name_Index</a></td><td><a href="#FT_Get_SubGlyph_Info">FT_Get_SubGlyph_Info</a></td></tr>
<tr><td><a href="#FT_HAS_MULTIPLE_MASTERS">FT_HAS_MULTIPLE_MASTERS</a></td><td><a href="#FT_Load_Char">FT_Load_Char</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_HAS_COLOR">FT_HAS_COLOR</a></td><td>&nbsp;</td><td><a href="#FT_Face_Internal">FT_Face_Internal</a></td></tr>
<tr><td>&nbsp;</td><td><a href="#FT_OPEN_MEMORY">FT_OPEN_MEMORY</a></td><td><a href="#FT_Size_Internal">FT_Size_Internal</a></td></tr>
<tr><td><a href="#FT_IS_SFNT">FT_IS_SFNT</a></td><td><a href="#FT_OPEN_STREAM">FT_OPEN_STREAM</a></td><td><a href="#FT_Slot_Internal">FT_Slot_Internal</a></td></tr>
<tr><td><a href="#FT_IS_SCALABLE">FT_IS_SCALABLE</a></td><td><a href="#FT_OPEN_PATHNAME">FT_OPEN_PATHNAME</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_IS_FIXED_WIDTH">FT_IS_FIXED_WIDTH</a></td><td><a href="#FT_OPEN_DRIVER">FT_OPEN_DRIVER</a></td><td><a href="#FT_FACE_FLAG_XXX">FT_FACE_FLAG_XXX</a></td></tr>
<tr><td><a href="#FT_IS_CID_KEYED">FT_IS_CID_KEYED</a></td><td><a href="#FT_OPEN_PARAMS">FT_OPEN_PARAMS</a></td><td><a href="#FT_STYLE_FLAG_XXX">FT_STYLE_FLAG_XXX</a></td></tr>
<tr><td><a href="#FT_IS_TRICKY">FT_IS_TRICKY</a></td><td>&nbsp;</td><td><a href="#FT_OPEN_XXX">FT_OPEN_XXX</a></td></tr>
<tr><td>&nbsp;</td><td><a href="#FT_LOAD_DEFAULT">FT_LOAD_DEFAULT</a></td><td><a href="#FT_LOAD_XXX">FT_LOAD_XXX</a></td></tr>
<tr><td><a href="#FT_STYLE_FLAG_BOLD">FT_STYLE_FLAG_BOLD</a></td><td><a href="#FT_LOAD_RENDER">FT_LOAD_RENDER</a></td><td><a href="#FT_LOAD_TARGET_XXX">FT_LOAD_TARGET_XXX</a></td></tr>
<tr><td><a href="#FT_STYLE_FLAG_ITALIC">FT_STYLE_FLAG_ITALIC</a></td><td><a href="#FT_LOAD_MONOCHROME">FT_LOAD_MONOCHROME</a></td><td><a href="#FT_SUBGLYPH_FLAG_XXX">FT_SUBGLYPH_FLAG_XXX</a></td></tr>
<tr><td>&nbsp;</td><td><a href="#FT_LOAD_LINEAR_DESIGN">FT_LOAD_LINEAR_DESIGN</a></td><td><a href="#FT_FSTYPE_XXX">FT_FSTYPE_XXX</a></td></tr>
<tr><td><a href="#FT_SizeRec">FT_SizeRec</a></td><td><a href="#FT_LOAD_NO_SCALE">FT_LOAD_NO_SCALE</a></td><td>&nbsp;</td></tr>
<tr><td><a href="#FT_Size_Metrics">FT_Size_Metrics</a></td><td><a href="#FT_LOAD_NO_HINTING">FT_LOAD_NO_HINTING</a></td><td><a href="#FT_HAS_FAST_GLYPHS">FT_HAS_FAST_GLYPHS</a></td></tr>
<tr><td>&nbsp;</td><td><a href="#FT_LOAD_NO_BITMAP">FT_LOAD_NO_BITMAP</a></td><td></td></tr>
<tr><td><a href="#FT_GlyphSlotRec">FT_GlyphSlotRec</a></td><td><a href="#FT_LOAD_NO_AUTOHINT">FT_LOAD_NO_AUTOHINT</a></td><td></td></tr>
</table>
<p>This section describes the most important public high-level API functions of FreeType&nbsp;2.</p>
<div class="section">
<h3 id="FT_Library">FT_Library</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_LibraryRec_ *<b>FT_Library</b>;
</pre>
<p>A handle to a FreeType library instance. Each &lsquo;library&rsquo; is completely independent from the others; it is the &lsquo;root&rsquo; of a set of objects like fonts, faces, sizes, etc.</p>
<p>It also embeds a memory manager (see <a href="ft2-system_interface.html#FT_Memory">FT_Memory</a>), as well as a scan-line converter object (see <a href="ft2-raster.html#FT_Raster">FT_Raster</a>).</p>
<p>In multi-threaded applications it is easiest to use one &lsquo;FT_Library&rsquo; object per thread. In case this is too cumbersome, a single &lsquo;FT_Library&rsquo; object across threads is possible also (since FreeType version 2.5.6), as long as a mutex lock is used around <a href="ft2-base_interface.html#FT_New_Face">FT_New_Face</a> and <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a>.</p>
<h4>note</h4>
<p>Library objects are normally created by <a href="ft2-base_interface.html#FT_Init_FreeType">FT_Init_FreeType</a>, and destroyed with <a href="ft2-base_interface.html#FT_Done_FreeType">FT_Done_FreeType</a>. If you need reference-counting (cf. <a href="ft2-module_management.html#FT_Reference_Library">FT_Reference_Library</a>), use <a href="ft2-module_management.html#FT_New_Library">FT_New_Library</a> and <a href="ft2-module_management.html#FT_Done_Library">FT_Done_Library</a>.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Face">FT_Face</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_FaceRec_* <b>FT_Face</b>;
</pre>
<p>A handle to a given typographic face object. A face object models a given typeface, in a given style.</p>
<h4>note</h4>
<p>Each face object also owns a single <a href="ft2-base_interface.html#FT_GlyphSlot">FT_GlyphSlot</a> object, as well as one or more <a href="ft2-base_interface.html#FT_Size">FT_Size</a> objects.</p>
<p>Use <a href="ft2-base_interface.html#FT_New_Face">FT_New_Face</a> or <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> to create a new face object from a given filepathname or a custom input stream.</p>
<p>Use <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a> to destroy it (along with its slot and sizes).</p>
<p>An &lsquo;FT_Face&rsquo; object can only be safely used from one thread at a time. Similarly, creation and destruction of &lsquo;FT_Face&rsquo; with the same <a href="ft2-base_interface.html#FT_Library">FT_Library</a> object can only be done from one thread at a time. On the other hand, functions like <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a> and its siblings are thread-safe and do not need the lock to be held as long as the same &lsquo;FT_Face&rsquo; object is not used from multiple threads at the same time.</p>
<h4>also</h4>
<p>See <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> for the publicly accessible fields of a given face object.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Size">FT_Size</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_SizeRec_* <b>FT_Size</b>;
</pre>
<p>A handle to an object used to model a face scaled to a given character size.</p>
<h4>note</h4>
<p>Each <a href="ft2-base_interface.html#FT_Face">FT_Face</a> has an <i>active</i> <a href="ft2-base_interface.html#FT_Size">FT_Size</a> object that is used by functions like <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a> to determine the scaling transformation that in turn is used to load and hint glyphs and metrics.</p>
<p>You can use <a href="ft2-base_interface.html#FT_Set_Char_Size">FT_Set_Char_Size</a>, <a href="ft2-base_interface.html#FT_Set_Pixel_Sizes">FT_Set_Pixel_Sizes</a>, <a href="ft2-base_interface.html#FT_Request_Size">FT_Request_Size</a> or even <a href="ft2-base_interface.html#FT_Select_Size">FT_Select_Size</a> to change the content (i.e., the scaling values) of the active <a href="ft2-base_interface.html#FT_Size">FT_Size</a>.</p>
<p>You can use <a href="ft2-sizes_management.html#FT_New_Size">FT_New_Size</a> to create additional size objects for a given <a href="ft2-base_interface.html#FT_Face">FT_Face</a>, but they won't be used by other functions until you activate it through <a href="ft2-sizes_management.html#FT_Activate_Size">FT_Activate_Size</a>. Only one size can be activated at any given time per face.</p>
<h4>also</h4>
<p>See <a href="ft2-base_interface.html#FT_SizeRec">FT_SizeRec</a> for the publicly accessible fields of a given size object.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_GlyphSlot">FT_GlyphSlot</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_GlyphSlotRec_* <b>FT_GlyphSlot</b>;
</pre>
<p>A handle to a given &lsquo;glyph slot&rsquo;. A slot is a container where it is possible to load any of the glyphs contained in its parent face.</p>
<p>In other words, each time you call <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a> or <a href="ft2-base_interface.html#FT_Load_Char">FT_Load_Char</a>, the slot's content is erased by the new glyph data, i.e., the glyph's metrics, its image (bitmap or outline), and other control information.</p>
<h4>also</h4>
<p>See <a href="ft2-base_interface.html#FT_GlyphSlotRec">FT_GlyphSlotRec</a> for the publicly accessible glyph fields.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_CharMap">FT_CharMap</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_CharMapRec_* <b>FT_CharMap</b>;
</pre>
<p>A handle to a given character map. A charmap is used to translate character codes in a given encoding into glyph indexes for its parent's face. Some font formats may provide several charmaps per font.</p>
<p>Each face object owns zero or more charmaps, but only one of them can be &lsquo;active&rsquo; and used by <a href="ft2-base_interface.html#FT_Get_Char_Index">FT_Get_Char_Index</a> or <a href="ft2-base_interface.html#FT_Load_Char">FT_Load_Char</a>.</p>
<p>The list of available charmaps in a face is available through the &lsquo;face-&gt;num_charmaps&rsquo; and &lsquo;face-&gt;charmaps&rsquo; fields of <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a>.</p>
<p>The currently active charmap is available as &lsquo;face-&gt;charmap&rsquo;. You should call <a href="ft2-base_interface.html#FT_Set_Charmap">FT_Set_Charmap</a> to change it.</p>
<h4>note</h4>
<p>When a new face is created (either through <a href="ft2-base_interface.html#FT_New_Face">FT_New_Face</a> or <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a>), the library looks for a Unicode charmap within the list and automatically activates it.</p>
<h4>also</h4>
<p>See <a href="ft2-base_interface.html#FT_CharMapRec">FT_CharMapRec</a> for the publicly accessible fields of a given character map.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Encoding">FT_Encoding</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">enum</span> FT_Encoding_
{
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_NONE">FT_ENCODING_NONE</a>, 0, 0, 0, 0 ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_MS_SYMBOL">FT_ENCODING_MS_SYMBOL</a>, 's', 'y', 'm', 'b' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_UNICODE">FT_ENCODING_UNICODE</a>, 'u', 'n', 'i', 'c' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_SJIS">FT_ENCODING_SJIS</a>, 's', 'j', 'i', 's' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_GB2312">FT_ENCODING_GB2312</a>, 'g', 'b', ' ', ' ' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_BIG5">FT_ENCODING_BIG5</a>, 'b', 'i', 'g', '5' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_WANSUNG">FT_ENCODING_WANSUNG</a>, 'w', 'a', 'n', 's' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_JOHAB">FT_ENCODING_JOHAB</a>, 'j', 'o', 'h', 'a' ),
/* for backwards compatibility */
<a href="ft2-base_interface.html#FT_ENCODING_MS_SJIS">FT_ENCODING_MS_SJIS</a> = <a href="ft2-base_interface.html#FT_ENCODING_SJIS">FT_ENCODING_SJIS</a>,
<a href="ft2-base_interface.html#FT_ENCODING_MS_GB2312">FT_ENCODING_MS_GB2312</a> = <a href="ft2-base_interface.html#FT_ENCODING_GB2312">FT_ENCODING_GB2312</a>,
<a href="ft2-base_interface.html#FT_ENCODING_MS_BIG5">FT_ENCODING_MS_BIG5</a> = <a href="ft2-base_interface.html#FT_ENCODING_BIG5">FT_ENCODING_BIG5</a>,
<a href="ft2-base_interface.html#FT_ENCODING_MS_WANSUNG">FT_ENCODING_MS_WANSUNG</a> = <a href="ft2-base_interface.html#FT_ENCODING_WANSUNG">FT_ENCODING_WANSUNG</a>,
<a href="ft2-base_interface.html#FT_ENCODING_MS_JOHAB">FT_ENCODING_MS_JOHAB</a> = <a href="ft2-base_interface.html#FT_ENCODING_JOHAB">FT_ENCODING_JOHAB</a>,
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_STANDARD">FT_ENCODING_ADOBE_STANDARD</a>, 'A', 'D', 'O', 'B' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_EXPERT">FT_ENCODING_ADOBE_EXPERT</a>, 'A', 'D', 'B', 'E' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_CUSTOM">FT_ENCODING_ADOBE_CUSTOM</a>, 'A', 'D', 'B', 'C' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_LATIN_1">FT_ENCODING_ADOBE_LATIN_1</a>, 'l', 'a', 't', '1' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_OLD_LATIN_2">FT_ENCODING_OLD_LATIN_2</a>, 'l', 'a', 't', '2' ),
<a href="ft2-base_interface.html#FT_ENC_TAG">FT_ENC_TAG</a>( <a href="ft2-base_interface.html#FT_ENCODING_APPLE_ROMAN">FT_ENCODING_APPLE_ROMAN</a>, 'a', 'r', 'm', 'n' )
} <b>FT_Encoding</b>;
/* these constants are deprecated; use the corresponding `<b>FT_Encoding</b>' */
/* values instead */
#define ft_encoding_none <a href="ft2-base_interface.html#FT_ENCODING_NONE">FT_ENCODING_NONE</a>
#define ft_encoding_unicode <a href="ft2-base_interface.html#FT_ENCODING_UNICODE">FT_ENCODING_UNICODE</a>
#define ft_encoding_symbol <a href="ft2-base_interface.html#FT_ENCODING_MS_SYMBOL">FT_ENCODING_MS_SYMBOL</a>
#define ft_encoding_latin_1 <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_LATIN_1">FT_ENCODING_ADOBE_LATIN_1</a>
#define ft_encoding_latin_2 <a href="ft2-base_interface.html#FT_ENCODING_OLD_LATIN_2">FT_ENCODING_OLD_LATIN_2</a>
#define ft_encoding_sjis <a href="ft2-base_interface.html#FT_ENCODING_SJIS">FT_ENCODING_SJIS</a>
#define ft_encoding_gb2312 <a href="ft2-base_interface.html#FT_ENCODING_GB2312">FT_ENCODING_GB2312</a>
#define ft_encoding_big5 <a href="ft2-base_interface.html#FT_ENCODING_BIG5">FT_ENCODING_BIG5</a>
#define ft_encoding_wansung <a href="ft2-base_interface.html#FT_ENCODING_WANSUNG">FT_ENCODING_WANSUNG</a>
#define ft_encoding_johab <a href="ft2-base_interface.html#FT_ENCODING_JOHAB">FT_ENCODING_JOHAB</a>
#define ft_encoding_adobe_standard <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_STANDARD">FT_ENCODING_ADOBE_STANDARD</a>
#define ft_encoding_adobe_expert <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_EXPERT">FT_ENCODING_ADOBE_EXPERT</a>
#define ft_encoding_adobe_custom <a href="ft2-base_interface.html#FT_ENCODING_ADOBE_CUSTOM">FT_ENCODING_ADOBE_CUSTOM</a>
#define ft_encoding_apple_roman <a href="ft2-base_interface.html#FT_ENCODING_APPLE_ROMAN">FT_ENCODING_APPLE_ROMAN</a>
</pre>
<p>An enumeration used to specify character sets supported by charmaps. Used in the <a href="ft2-base_interface.html#FT_Select_Charmap">FT_Select_Charmap</a> API function.</p>
<h4>note</h4>
<p>Despite the name, this enumeration lists specific character repertories (i.e., charsets), and not text encoding methods (e.g., UTF-8, UTF-16, etc.).</p>
<p>Other encodings might be defined in the future.</p>
<h4>values</h4>
<table class="fields">
<tr><td class="val" id="FT_ENCODING_NONE">FT_ENCODING_NONE</td><td class="desc">
<p>The encoding value&nbsp;0 is reserved.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_UNICODE">FT_ENCODING_UNICODE</td><td class="desc">
<p>Corresponds to the Unicode character set. This value covers all versions of the Unicode repertoire, including ASCII and Latin-1. Most fonts include a Unicode charmap, but not all of them.</p>
<p>For example, if you want to access Unicode value U+1F028 (and the font contains it), use value 0x1F028 as the input value for <a href="ft2-base_interface.html#FT_Get_Char_Index">FT_Get_Char_Index</a>.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_MS_SYMBOL">FT_ENCODING_MS_SYMBOL</td><td class="desc">
<p>Corresponds to the Microsoft Symbol encoding, used to encode mathematical symbols and wingdings. For more information, see &lsquo;<a href="http://www.microsoft.com/typography/otspec/recom.htm">http://www.microsoft.com/typography/otspec/recom.htm</a>&rsquo;, &lsquo;<a href="http://www.kostis.net/charsets/symbol.htm">http://www.kostis.net/charsets/symbol.htm</a>&rsquo;, and &lsquo;<a href="http://www.kostis.net/charsets/wingding.htm">http://www.kostis.net/charsets/wingding.htm</a>&rsquo;.</p>
<p>This encoding uses character codes from the PUA (Private Unicode Area) in the range U+F020-U+F0FF.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_SJIS">FT_ENCODING_SJIS</td><td class="desc">
<p>Corresponds to Japanese SJIS encoding. More info at at &lsquo;<a href="http://en.wikipedia.org/wiki/Shift_JIS">http://en.wikipedia.org/wiki/Shift_JIS</a>&rsquo;. See note on multi-byte encodings below.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_GB2312">FT_ENCODING_GB2312</td><td class="desc">
<p>Corresponds to an encoding system for Simplified Chinese as used used in mainland China.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_BIG5">FT_ENCODING_BIG5</td><td class="desc">
<p>Corresponds to an encoding system for Traditional Chinese as used in Taiwan and Hong Kong.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_WANSUNG">FT_ENCODING_WANSUNG</td><td class="desc">
<p>Corresponds to the Korean encoding system known as Wansung. For more information see &lsquo;<a href="https://msdn.microsoft.com/en-US/goglobal/cc305154">https://msdn.microsoft.com/en-US/goglobal/cc305154</a>&rsquo;.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_JOHAB">FT_ENCODING_JOHAB</td><td class="desc">
<p>The Korean standard character set (KS&nbsp;C 5601-1992), which corresponds to MS Windows code page 1361. This character set includes all possible Hangeul character combinations.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_ADOBE_LATIN_1">FT_ENCODING_ADOBE_LATIN_1</td><td class="desc">
<p>Corresponds to a Latin-1 encoding as defined in a Type&nbsp;1 PostScript font. It is limited to 256 character codes.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_ADOBE_STANDARD">FT_ENCODING_ADOBE_STANDARD</td><td class="desc">
<p>Corresponds to the Adobe Standard encoding, as found in Type&nbsp;1, CFF, and OpenType/CFF fonts. It is limited to 256 character codes.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_ADOBE_EXPERT">FT_ENCODING_ADOBE_EXPERT</td><td class="desc">
<p>Corresponds to the Adobe Expert encoding, as found in Type&nbsp;1, CFF, and OpenType/CFF fonts. It is limited to 256 character codes.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_ADOBE_CUSTOM">FT_ENCODING_ADOBE_CUSTOM</td><td class="desc">
<p>Corresponds to a custom encoding, as found in Type&nbsp;1, CFF, and OpenType/CFF fonts. It is limited to 256 character codes.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_APPLE_ROMAN">FT_ENCODING_APPLE_ROMAN</td><td class="desc">
<p>Corresponds to the 8-bit Apple roman encoding. Many TrueType and OpenType fonts contain a charmap for this encoding, since older versions of Mac OS are able to use it.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_OLD_LATIN_2">FT_ENCODING_OLD_LATIN_2</td><td class="desc">
<p>This value is deprecated and was never used nor reported by FreeType. Don't use or test for it.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_MS_SJIS">FT_ENCODING_MS_SJIS</td><td class="desc">
<p>Same as FT_ENCODING_SJIS. Deprecated.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_MS_GB2312">FT_ENCODING_MS_GB2312</td><td class="desc">
<p>Same as FT_ENCODING_GB2312. Deprecated.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_MS_BIG5">FT_ENCODING_MS_BIG5</td><td class="desc">
<p>Same as FT_ENCODING_BIG5. Deprecated.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_MS_WANSUNG">FT_ENCODING_MS_WANSUNG</td><td class="desc">
<p>Same as FT_ENCODING_WANSUNG. Deprecated.</p>
</td></tr>
<tr><td class="val" id="FT_ENCODING_MS_JOHAB">FT_ENCODING_MS_JOHAB</td><td class="desc">
<p>Same as FT_ENCODING_JOHAB. Deprecated.</p>
</td></tr>
</table>
<h4>note</h4>
<p>By default, FreeType automatically synthesizes a Unicode charmap for PostScript fonts, using their glyph names dictionaries. However, it also reports the encodings defined explicitly in the font file, for the cases when they are needed, with the Adobe values as well.</p>
<p>FT_ENCODING_NONE is set by the BDF and PCF drivers if the charmap is neither Unicode nor ISO-8859-1 (otherwise it is set to FT_ENCODING_UNICODE). Use <a href="ft2-bdf_fonts.html#FT_Get_BDF_Charset_ID">FT_Get_BDF_Charset_ID</a> to find out which encoding is really present. If, for example, the &lsquo;cs_registry&rsquo; field is &lsquo;KOI8&rsquo; and the &lsquo;cs_encoding&rsquo; field is &lsquo;R&rsquo;, the font is encoded in KOI8-R.</p>
<p>FT_ENCODING_NONE is always set (with a single exception) by the winfonts driver. Use <a href="ft2-winfnt_fonts.html#FT_Get_WinFNT_Header">FT_Get_WinFNT_Header</a> and examine the &lsquo;charset&rsquo; field of the <a href="ft2-winfnt_fonts.html#FT_WinFNT_HeaderRec">FT_WinFNT_HeaderRec</a> structure to find out which encoding is really present. For example, <a href="ft2-winfnt_fonts.html#FT_WinFNT_ID_XXX">FT_WinFNT_ID_CP1251</a> (204) means Windows code page 1251 (for Russian).</p>
<p>FT_ENCODING_NONE is set if &lsquo;platform_id&rsquo; is <a href="ft2-truetype_tables.html#TT_PLATFORM_XXX">TT_PLATFORM_MACINTOSH</a> and &lsquo;encoding_id&rsquo; is not <a href="ft2-truetype_tables.html#TT_MAC_ID_XXX">TT_MAC_ID_ROMAN</a> (otherwise it is set to FT_ENCODING_APPLE_ROMAN).</p>
<p>If &lsquo;platform_id&rsquo; is <a href="ft2-truetype_tables.html#TT_PLATFORM_XXX">TT_PLATFORM_MACINTOSH</a>, use the function <a href="ft2-truetype_tables.html#FT_Get_CMap_Language_ID">FT_Get_CMap_Language_ID</a> to query the Mac language ID that may be needed to be able to distinguish Apple encoding variants. See</p>
<p><a href="http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/Readme.txt">http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/Readme.txt</a></p>
<p>to get an idea how to do that. Basically, if the language ID is&nbsp;0, don't use it, otherwise subtract 1 from the language ID. Then examine &lsquo;encoding_id&rsquo;. If, for example, &lsquo;encoding_id&rsquo; is <a href="ft2-truetype_tables.html#TT_MAC_ID_XXX">TT_MAC_ID_ROMAN</a> and the language ID (minus&nbsp;1) is &lsquo;TT_MAC_LANGID_GREEK&rsquo;, it is the Greek encoding, not Roman. <a href="ft2-truetype_tables.html#TT_MAC_ID_XXX">TT_MAC_ID_ARABIC</a> with &lsquo;TT_MAC_LANGID_FARSI&rsquo; means the Farsi variant the Arabic encoding.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_ENC_TAG">FT_ENC_TAG</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#ifndef <b>FT_ENC_TAG</b>
#define <b>FT_ENC_TAG</b>( value, a, b, c, d ) \
value = ( ( (<a href="ft2-basic_types.html#FT_UInt32">FT_UInt32</a>)(a) &lt;&lt; 24 ) | \
( (<a href="ft2-basic_types.html#FT_UInt32">FT_UInt32</a>)(b) &lt;&lt; 16 ) | \
( (<a href="ft2-basic_types.html#FT_UInt32">FT_UInt32</a>)(c) &lt;&lt; 8 ) | \
(<a href="ft2-basic_types.html#FT_UInt32">FT_UInt32</a>)(d) )
#endif /* <b>FT_ENC_TAG</b> */
</pre>
<p>This macro converts four-letter tags into an unsigned long. It is used to define &lsquo;encoding&rsquo; identifiers (see <a href="ft2-base_interface.html#FT_Encoding">FT_Encoding</a>).</p>
<h4>note</h4>
<p>Since many 16-bit compilers don't like 32-bit enumerations, you should redefine this macro in case of problems to something like this:</p>
<pre class="colored">
#define FT_ENC_TAG( value, a, b, c, d ) value
</pre>
<p>to get a simple enumeration without assigning special numbers.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_FaceRec">FT_FaceRec</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_FaceRec_
{
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> num_faces;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> face_index;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> face_flags;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> style_flags;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> num_glyphs;
<a href="ft2-basic_types.html#FT_String">FT_String</a>* family_name;
<a href="ft2-basic_types.html#FT_String">FT_String</a>* style_name;
<a href="ft2-basic_types.html#FT_Int">FT_Int</a> num_fixed_sizes;
<a href="ft2-base_interface.html#FT_Bitmap_Size">FT_Bitmap_Size</a>* available_sizes;
<a href="ft2-basic_types.html#FT_Int">FT_Int</a> num_charmaps;
<a href="ft2-base_interface.html#FT_CharMap">FT_CharMap</a>* charmaps;
<a href="ft2-basic_types.html#FT_Generic">FT_Generic</a> generic;
/*# The following member variables (down to `underline_thickness') */
/*# are only relevant to scalable outlines; cf. @<a href="ft2-base_interface.html#FT_Bitmap_Size">FT_Bitmap_Size</a> */
/*# for bitmap fonts. */
<a href="ft2-basic_types.html#FT_BBox">FT_BBox</a> bbox;
<a href="ft2-basic_types.html#FT_UShort">FT_UShort</a> units_per_EM;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> ascender;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> descender;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> height;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> max_advance_width;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> max_advance_height;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> underline_position;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> underline_thickness;
<a href="ft2-base_interface.html#FT_GlyphSlot">FT_GlyphSlot</a> glyph;
<a href="ft2-base_interface.html#FT_Size">FT_Size</a> size;
<a href="ft2-base_interface.html#FT_CharMap">FT_CharMap</a> charmap;
/*@private begin */
<a href="ft2-module_management.html#FT_Driver">FT_Driver</a> driver;
<a href="ft2-system_interface.html#FT_Memory">FT_Memory</a> memory;
<a href="ft2-system_interface.html#FT_Stream">FT_Stream</a> stream;
<a href="ft2-list_processing.html#FT_ListRec">FT_ListRec</a> sizes_list;
<a href="ft2-basic_types.html#FT_Generic">FT_Generic</a> autohint; /* face-specific auto-hinter data */
<span class="keyword">void</span>* extensions; /* unused */
<a href="ft2-base_interface.html#FT_Face_Internal">FT_Face_Internal</a> internal;
/*@private end */
} <b>FT_FaceRec</b>;
</pre>
<p>FreeType root face class structure. A face object models a typeface in a font file.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="num_faces">num_faces</td><td class="desc">
<p>The number of faces in the font file. Some font formats can have multiple faces in a font file.</p>
</td></tr>
<tr><td class="val" id="face_index">face_index</td><td class="desc">
<p>This field holds two different values. Bits 0-15 are the index of the face in the font file (starting with value&nbsp;0). They are set to&nbsp;0 if there is only one face in the font file.</p>
<p>Bits 16-30 are relevant to GX variation fonts only, holding the named instance index for the current face index (starting with value&nbsp;1; value&nbsp;0 indicates font access without GX variation data). For non-GX fonts, bits 16-30 are ignored. If we have the third named instance of face&nbsp;4, say, &lsquo;face_index&rsquo; is set to 0x00030004.</p>
<p>Bit 31 is always zero (this is, &lsquo;face_index&rsquo; is always a positive value).</p>
</td></tr>
<tr><td class="val" id="face_flags">face_flags</td><td class="desc">
<p>A set of bit flags that give important information about the face; see <a href="ft2-base_interface.html#FT_FACE_FLAG_XXX">FT_FACE_FLAG_XXX</a> for the details.</p>
</td></tr>
<tr><td class="val" id="style_flags">style_flags</td><td class="desc">
<p>The lower 16&nbsp;bits contain a set of bit flags indicating the style of the face; see <a href="ft2-base_interface.html#FT_STYLE_FLAG_XXX">FT_STYLE_FLAG_XXX</a> for the details. Bits 16-30 hold the number of named instances available for the current face if we have a GX variation (sub)font. Bit 31 is always zero (this is, &lsquo;style_flags&rsquo; is always a positive value).</p>
</td></tr>
<tr><td class="val" id="num_glyphs">num_glyphs</td><td class="desc">
<p>The number of glyphs in the face. If the face is scalable and has sbits (see &lsquo;num_fixed_sizes&rsquo;), it is set to the number of outline glyphs.</p>
<p>For CID-keyed fonts, this value gives the highest CID used in the font.</p>
</td></tr>
<tr><td class="val" id="family_name">family_name</td><td class="desc">
<p>The face's family name. This is an ASCII string, usually in English, that describes the typeface's family (like &lsquo;Times New Roman&rsquo;, &lsquo;Bodoni&rsquo;, &lsquo;Garamond&rsquo;, etc). This is a least common denominator used to list fonts. Some formats (TrueType &amp; OpenType) provide localized and Unicode versions of this string. Applications should use the format specific interface to access them. Can be NULL (e.g., in fonts embedded in a PDF file).</p>
<p>In case the font doesn't provide a specific family name entry, FreeType tries to synthesize one, deriving it from other name entries.</p>
</td></tr>
<tr><td class="val" id="style_name">style_name</td><td class="desc">
<p>The face's style name. This is an ASCII string, usually in English, that describes the typeface's style (like &lsquo;Italic&rsquo;, &lsquo;Bold&rsquo;, &lsquo;Condensed&rsquo;, etc). Not all font formats provide a style name, so this field is optional, and can be set to NULL. As for &lsquo;family_name&rsquo;, some formats provide localized and Unicode versions of this string. Applications should use the format specific interface to access them.</p>
</td></tr>
<tr><td class="val" id="num_fixed_sizes">num_fixed_sizes</td><td class="desc">
<p>The number of bitmap strikes in the face. Even if the face is scalable, there might still be bitmap strikes, which are called &lsquo;sbits&rsquo; in that case.</p>
</td></tr>
<tr><td class="val" id="available_sizes">available_sizes</td><td class="desc">
<p>An array of <a href="ft2-base_interface.html#FT_Bitmap_Size">FT_Bitmap_Size</a> for all bitmap strikes in the face. It is set to NULL if there is no bitmap strike.</p>
</td></tr>
<tr><td class="val" id="num_charmaps">num_charmaps</td><td class="desc">
<p>The number of charmaps in the face.</p>
</td></tr>
<tr><td class="val" id="charmaps">charmaps</td><td class="desc">
<p>An array of the charmaps of the face.</p>
</td></tr>
<tr><td class="val" id="generic">generic</td><td class="desc">
<p>A field reserved for client uses. See the <a href="ft2-basic_types.html#FT_Generic">FT_Generic</a> type description.</p>
</td></tr>
<tr><td class="val" id="bbox">bbox</td><td class="desc">
<p>The font bounding box. Coordinates are expressed in font units (see &lsquo;units_per_EM&rsquo;). The box is large enough to contain any glyph from the font. Thus, &lsquo;bbox.yMax&rsquo; can be seen as the &lsquo;maximum ascender&rsquo;, and &lsquo;bbox.yMin&rsquo; as the &lsquo;minimum descender&rsquo;. Only relevant for scalable formats.</p>
<p>Note that the bounding box might be off by (at least) one pixel for hinted fonts. See <a href="ft2-base_interface.html#FT_Size_Metrics">FT_Size_Metrics</a> for further discussion.</p>
</td></tr>
<tr><td class="val" id="units_per_EM">units_per_EM</td><td class="desc">
<p>The number of font units per EM square for this face. This is typically 2048 for TrueType fonts, and 1000 for Type&nbsp;1 fonts. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="ascender">ascender</td><td class="desc">
<p>The typographic ascender of the face, expressed in font units. For font formats not having this information, it is set to &lsquo;bbox.yMax&rsquo;. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="descender">descender</td><td class="desc">
<p>The typographic descender of the face, expressed in font units. For font formats not having this information, it is set to &lsquo;bbox.yMin&rsquo;. Note that this field is usually negative. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="height">height</td><td class="desc">
<p>This value is the vertical distance between two consecutive baselines, expressed in font units. It is always positive. Only relevant for scalable formats.</p>
<p>If you want the global glyph height, use &lsquo;ascender - descender&rsquo;.</p>
</td></tr>
<tr><td class="val" id="max_advance_width">max_advance_width</td><td class="desc">
<p>The maximum advance width, in font units, for all glyphs in this face. This can be used to make word wrapping computations faster. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="max_advance_height">max_advance_height</td><td class="desc">
<p>The maximum advance height, in font units, for all glyphs in this face. This is only relevant for vertical layouts, and is set to &lsquo;height&rsquo; for fonts that do not provide vertical metrics. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="underline_position">underline_position</td><td class="desc">
<p>The position, in font units, of the underline line for this face. It is the center of the underlining stem. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="underline_thickness">underline_thickness</td><td class="desc">
<p>The thickness, in font units, of the underline for this face. Only relevant for scalable formats.</p>
</td></tr>
<tr><td class="val" id="glyph">glyph</td><td class="desc">
<p>The face's associated glyph slot(s).</p>
</td></tr>
<tr><td class="val" id="size">size</td><td class="desc">
<p>The current active size for this face.</p>
</td></tr>
<tr><td class="val" id="charmap">charmap</td><td class="desc">
<p>The current active charmap for this face.</p>
</td></tr>
</table>
<h4>note</h4>
<p>Fields may be changed after a call to <a href="ft2-base_interface.html#FT_Attach_File">FT_Attach_File</a> or <a href="ft2-base_interface.html#FT_Attach_Stream">FT_Attach_Stream</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_HORIZONTAL">FT_HAS_HORIZONTAL</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_HORIZONTAL</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_HORIZONTAL">FT_FACE_FLAG_HORIZONTAL</a> )
</pre>
<p>A macro that returns true whenever a face object contains horizontal metrics (this is true for all font formats though).</p>
<h4>also</h4>
<p><a href="ft2-base_interface.html#FT_HAS_VERTICAL">FT_HAS_VERTICAL</a> can be used to check for vertical metrics.</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_VERTICAL">FT_HAS_VERTICAL</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_VERTICAL</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_VERTICAL">FT_FACE_FLAG_VERTICAL</a> )
</pre>
<p>A macro that returns true whenever a face object contains real vertical metrics (and not only synthesized ones).</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_KERNING">FT_HAS_KERNING</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_KERNING</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_KERNING">FT_FACE_FLAG_KERNING</a> )
</pre>
<p>A macro that returns true whenever a face object contains kerning data that can be accessed with <a href="ft2-base_interface.html#FT_Get_Kerning">FT_Get_Kerning</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_FIXED_SIZES">FT_HAS_FIXED_SIZES</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_FIXED_SIZES</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_FIXED_SIZES">FT_FACE_FLAG_FIXED_SIZES</a> )
</pre>
<p>A macro that returns true whenever a face object contains some embedded bitmaps. See the &lsquo;available_sizes&rsquo; field of the <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> structure.</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_GLYPH_NAMES">FT_HAS_GLYPH_NAMES</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_GLYPH_NAMES</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_GLYPH_NAMES">FT_FACE_FLAG_GLYPH_NAMES</a> )
</pre>
<p>A macro that returns true whenever a face object contains some glyph names that can be accessed through <a href="ft2-base_interface.html#FT_Get_Glyph_Name">FT_Get_Glyph_Name</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_MULTIPLE_MASTERS">FT_HAS_MULTIPLE_MASTERS</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_MULTIPLE_MASTERS</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_MULTIPLE_MASTERS">FT_FACE_FLAG_MULTIPLE_MASTERS</a> )
</pre>
<p>A macro that returns true whenever a face object contains some multiple masters. The functions provided by <a href="ft2-header_file_macros.html#FT_MULTIPLE_MASTERS_H">FT_MULTIPLE_MASTERS_H</a> are then available to choose the exact design you want.</p>
<hr>
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<div class="section">
<h3 id="FT_HAS_COLOR">FT_HAS_COLOR</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_HAS_COLOR</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_COLOR">FT_FACE_FLAG_COLOR</a> )
</pre>
<p>A macro that returns true whenever a face object contains tables for color glyphs.</p>
<hr>
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<div class="section">
<h3 id="FT_IS_SFNT">FT_IS_SFNT</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_IS_SFNT</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_SFNT">FT_FACE_FLAG_SFNT</a> )
</pre>
<p>A macro that returns true whenever a face object contains a font whose format is based on the SFNT storage scheme. This usually means: TrueType fonts, OpenType fonts, as well as SFNT-based embedded bitmap fonts.</p>
<p>If this macro is true, all functions defined in <a href="ft2-header_file_macros.html#FT_SFNT_NAMES_H">FT_SFNT_NAMES_H</a> and <a href="ft2-header_file_macros.html#FT_TRUETYPE_TABLES_H">FT_TRUETYPE_TABLES_H</a> are available.</p>
<hr>
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<div class="section">
<h3 id="FT_IS_SCALABLE">FT_IS_SCALABLE</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_IS_SCALABLE</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_SCALABLE">FT_FACE_FLAG_SCALABLE</a> )
</pre>
<p>A macro that returns true whenever a face object contains a scalable font face (true for TrueType, Type&nbsp;1, Type&nbsp;42, CID, OpenType/CFF, and PFR font formats.</p>
<hr>
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<div class="section">
<h3 id="FT_IS_FIXED_WIDTH">FT_IS_FIXED_WIDTH</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_IS_FIXED_WIDTH</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_FIXED_WIDTH">FT_FACE_FLAG_FIXED_WIDTH</a> )
</pre>
<p>A macro that returns true whenever a face object contains a font face that contains fixed-width (or &lsquo;monospace&rsquo;, &lsquo;fixed-pitch&rsquo;, etc.) glyphs.</p>
<hr>
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<div class="section">
<h3 id="FT_IS_CID_KEYED">FT_IS_CID_KEYED</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_IS_CID_KEYED</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_CID_KEYED">FT_FACE_FLAG_CID_KEYED</a> )
</pre>
<p>A macro that returns true whenever a face object contains a CID-keyed font. See the discussion of <a href="ft2-base_interface.html#FT_FACE_FLAG_XXX">FT_FACE_FLAG_CID_KEYED</a> for more details.</p>
<p>If this macro is true, all functions defined in <a href="ft2-header_file_macros.html#FT_CID_H">FT_CID_H</a> are available.</p>
<hr>
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<div class="section">
<h3 id="FT_IS_TRICKY">FT_IS_TRICKY</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_IS_TRICKY</b>( face ) \
( face-&gt;face_flags &amp; <a href="ft2-base_interface.html#FT_FACE_FLAG_TRICKY">FT_FACE_FLAG_TRICKY</a> )
</pre>
<p>A macro that returns true whenever a face represents a &lsquo;tricky&rsquo; font. See the discussion of <a href="ft2-base_interface.html#FT_FACE_FLAG_XXX">FT_FACE_FLAG_TRICKY</a> for more details.</p>
<hr>
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<div class="section">
<h3 id="FT_SizeRec">FT_SizeRec</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_SizeRec_
{
<a href="ft2-base_interface.html#FT_Face">FT_Face</a> face; /* parent face object */
<a href="ft2-basic_types.html#FT_Generic">FT_Generic</a> generic; /* generic pointer for client uses */
<a href="ft2-base_interface.html#FT_Size_Metrics">FT_Size_Metrics</a> metrics; /* size metrics */
<a href="ft2-base_interface.html#FT_Size_Internal">FT_Size_Internal</a> internal;
} <b>FT_SizeRec</b>;
</pre>
<p>FreeType root size class structure. A size object models a face object at a given size.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>Handle to the parent face object.</p>
</td></tr>
<tr><td class="val" id="generic">generic</td><td class="desc">
<p>A typeless pointer, unused by the FreeType library or any of its drivers. It can be used by client applications to link their own data to each size object.</p>
</td></tr>
<tr><td class="val" id="metrics">metrics</td><td class="desc">
<p>Metrics for this size object. This field is read-only.</p>
</td></tr>
</table>
<hr>
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<div class="section">
<h3 id="FT_Size_Metrics">FT_Size_Metrics</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Size_Metrics_
{
<a href="ft2-basic_types.html#FT_UShort">FT_UShort</a> x_ppem; /* horizontal pixels per EM */
<a href="ft2-basic_types.html#FT_UShort">FT_UShort</a> y_ppem; /* vertical pixels per EM */
<a href="ft2-basic_types.html#FT_Fixed">FT_Fixed</a> x_scale; /* scaling values used to convert font */
<a href="ft2-basic_types.html#FT_Fixed">FT_Fixed</a> y_scale; /* units to 26.6 fractional pixels */
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> ascender; /* ascender in 26.6 frac. pixels */
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> descender; /* descender in 26.6 frac. pixels */
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> height; /* text height in 26.6 frac. pixels */
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> max_advance; /* max horizontal advance, in 26.6 pixels */
} <b>FT_Size_Metrics</b>;
</pre>
<p>The size metrics structure gives the metrics of a size object.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="x_ppem">x_ppem</td><td class="desc">
<p>The width of the scaled EM square in pixels, hence the term &lsquo;ppem&rsquo; (pixels per EM). It is also referred to as &lsquo;nominal width&rsquo;.</p>
</td></tr>
<tr><td class="val" id="y_ppem">y_ppem</td><td class="desc">
<p>The height of the scaled EM square in pixels, hence the term &lsquo;ppem&rsquo; (pixels per EM). It is also referred to as &lsquo;nominal height&rsquo;.</p>
</td></tr>
<tr><td class="val" id="x_scale">x_scale</td><td class="desc">
<p>A 16.16 fractional scaling value used to convert horizontal metrics from font units to 26.6 fractional pixels. Only relevant for scalable font formats.</p>
</td></tr>
<tr><td class="val" id="y_scale">y_scale</td><td class="desc">
<p>A 16.16 fractional scaling value used to convert vertical metrics from font units to 26.6 fractional pixels. Only relevant for scalable font formats.</p>
</td></tr>
<tr><td class="val" id="ascender">ascender</td><td class="desc">
<p>The ascender in 26.6 fractional pixels. See <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> for the details.</p>
</td></tr>
<tr><td class="val" id="descender">descender</td><td class="desc">
<p>The descender in 26.6 fractional pixels. See <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> for the details.</p>
</td></tr>
<tr><td class="val" id="height">height</td><td class="desc">
<p>The height in 26.6 fractional pixels. See <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> for the details.</p>
</td></tr>
<tr><td class="val" id="max_advance">max_advance</td><td class="desc">
<p>The maximum advance width in 26.6 fractional pixels. See <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> for the details.</p>
</td></tr>
</table>
<h4>note</h4>
<p>The scaling values, if relevant, are determined first during a size changing operation. The remaining fields are then set by the driver. For scalable formats, they are usually set to scaled values of the corresponding fields in <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a>.</p>
<p>Note that due to glyph hinting, these values might not be exact for certain fonts. Thus they must be treated as unreliable with an error margin of at least one pixel!</p>
<p>Indeed, the only way to get the exact metrics is to render <i>all</i> glyphs. As this would be a definite performance hit, it is up to client applications to perform such computations.</p>
<p>The FT_Size_Metrics structure is valid for bitmap fonts also.</p>
<hr>
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<div class="section">
<h3 id="FT_GlyphSlotRec">FT_GlyphSlotRec</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_GlyphSlotRec_
{
<a href="ft2-base_interface.html#FT_Library">FT_Library</a> library;
<a href="ft2-base_interface.html#FT_Face">FT_Face</a> face;
<a href="ft2-base_interface.html#FT_GlyphSlot">FT_GlyphSlot</a> next;
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> reserved; /* retained for binary compatibility */
<a href="ft2-basic_types.html#FT_Generic">FT_Generic</a> generic;
<a href="ft2-base_interface.html#FT_Glyph_Metrics">FT_Glyph_Metrics</a> metrics;
<a href="ft2-basic_types.html#FT_Fixed">FT_Fixed</a> linearHoriAdvance;
<a href="ft2-basic_types.html#FT_Fixed">FT_Fixed</a> linearVertAdvance;
<a href="ft2-basic_types.html#FT_Vector">FT_Vector</a> advance;
<a href="ft2-basic_types.html#FT_Glyph_Format">FT_Glyph_Format</a> format;
<a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a> bitmap;
<a href="ft2-basic_types.html#FT_Int">FT_Int</a> bitmap_left;
<a href="ft2-basic_types.html#FT_Int">FT_Int</a> bitmap_top;
<a href="ft2-outline_processing.html#FT_Outline">FT_Outline</a> outline;
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> num_subglyphs;
<a href="ft2-base_interface.html#FT_SubGlyph">FT_SubGlyph</a> subglyphs;
<span class="keyword">void</span>* control_data;
<span class="keyword">long</span> control_len;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> lsb_delta;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> rsb_delta;
<span class="keyword">void</span>* other;
<a href="ft2-base_interface.html#FT_Slot_Internal">FT_Slot_Internal</a> internal;
} <b>FT_GlyphSlotRec</b>;
</pre>
<p>FreeType root glyph slot class structure. A glyph slot is a container where individual glyphs can be loaded, be they in outline or bitmap format.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to the FreeType library instance this slot belongs to.</p>
</td></tr>
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the parent face object.</p>
</td></tr>
<tr><td class="val" id="next">next</td><td class="desc">
<p>In some cases (like some font tools), several glyph slots per face object can be a good thing. As this is rare, the glyph slots are listed through a direct, single-linked list using its &lsquo;next&rsquo; field.</p>
</td></tr>
<tr><td class="val" id="generic">generic</td><td class="desc">
<p>A typeless pointer unused by the FreeType library or any of its drivers. It can be used by client applications to link their own data to each glyph slot object.</p>
</td></tr>
<tr><td class="val" id="metrics">metrics</td><td class="desc">
<p>The metrics of the last loaded glyph in the slot. The returned values depend on the last load flags (see the <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a> API function) and can be expressed either in 26.6 fractional pixels or font units.</p>
<p>Note that even when the glyph image is transformed, the metrics are not.</p>
</td></tr>
<tr><td class="val" id="linearHoriAdvance">linearHoriAdvance</td><td class="desc">
<p>The advance width of the unhinted glyph. Its value is expressed in 16.16 fractional pixels, unless <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_LINEAR_DESIGN</a> is set when loading the glyph. This field can be important to perform correct WYSIWYG layout. Only relevant for outline glyphs.</p>
</td></tr>
<tr><td class="val" id="linearVertAdvance">linearVertAdvance</td><td class="desc">
<p>The advance height of the unhinted glyph. Its value is expressed in 16.16 fractional pixels, unless <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_LINEAR_DESIGN</a> is set when loading the glyph. This field can be important to perform correct WYSIWYG layout. Only relevant for outline glyphs.</p>
</td></tr>
<tr><td class="val" id="advance">advance</td><td class="desc">
<p>This shorthand is, depending on <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_IGNORE_TRANSFORM</a>, the transformed (hinted) advance width for the glyph, in 26.6 fractional pixel format. As specified with <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_VERTICAL_LAYOUT</a>, it uses either the &lsquo;horiAdvance&rsquo; or the &lsquo;vertAdvance&rsquo; value of &lsquo;metrics&rsquo; field.</p>
</td></tr>
<tr><td class="val" id="format">format</td><td class="desc">
<p>This field indicates the format of the image contained in the glyph slot. Typically <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_BITMAP</a>, <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_OUTLINE</a>, or <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_COMPOSITE</a>, but others are possible.</p>
</td></tr>
<tr><td class="val" id="bitmap">bitmap</td><td class="desc">
<p>This field is used as a bitmap descriptor when the slot format is <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_BITMAP</a>. Note that the address and content of the bitmap buffer can change between calls of <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a> and a few other functions.</p>
</td></tr>
<tr><td class="val" id="bitmap_left">bitmap_left</td><td class="desc">
<p>The bitmap's left bearing expressed in integer pixels. Only valid if the format is <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_BITMAP</a>, this is, if the glyph slot contains a bitmap.</p>
</td></tr>
<tr><td class="val" id="bitmap_top">bitmap_top</td><td class="desc">
<p>The bitmap's top bearing expressed in integer pixels. Remember that this is the distance from the baseline to the top-most glyph scanline, upwards y&nbsp;coordinates being <b>positive</b>.</p>
</td></tr>
<tr><td class="val" id="outline">outline</td><td class="desc">
<p>The outline descriptor for the current glyph image if its format is <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_OUTLINE</a>. Once a glyph is loaded, &lsquo;outline&rsquo; can be transformed, distorted, embolded, etc. However, it must not be freed.</p>
</td></tr>
<tr><td class="val" id="num_subglyphs">num_subglyphs</td><td class="desc">
<p>The number of subglyphs in a composite glyph. This field is only valid for the composite glyph format that should normally only be loaded with the <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_NO_RECURSE</a> flag.</p>
</td></tr>
<tr><td class="val" id="subglyphs">subglyphs</td><td class="desc">
<p>An array of subglyph descriptors for composite glyphs. There are &lsquo;num_subglyphs&rsquo; elements in there. Currently internal to FreeType.</p>
</td></tr>
<tr><td class="val" id="control_data">control_data</td><td class="desc">
<p>Certain font drivers can also return the control data for a given glyph image (e.g. TrueType bytecode, Type&nbsp;1 charstrings, etc.). This field is a pointer to such data.</p>
</td></tr>
<tr><td class="val" id="control_len">control_len</td><td class="desc">
<p>This is the length in bytes of the control data.</p>
</td></tr>
<tr><td class="val" id="other">other</td><td class="desc">
<p>Really wicked formats can use this pointer to present their own glyph image to client applications. Note that the application needs to know about the image format.</p>
</td></tr>
<tr><td class="val" id="lsb_delta">lsb_delta</td><td class="desc">
<p>The difference between hinted and unhinted left side bearing while auto-hinting is active. Zero otherwise.</p>
</td></tr>
<tr><td class="val" id="rsb_delta">rsb_delta</td><td class="desc">
<p>The difference between hinted and unhinted right side bearing while auto-hinting is active. Zero otherwise.</p>
</td></tr>
</table>
<h4>note</h4>
<p>If <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a> is called with default flags (see <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_DEFAULT</a>) the glyph image is loaded in the glyph slot in its native format (e.g., an outline glyph for TrueType and Type&nbsp;1 formats).</p>
<p>This image can later be converted into a bitmap by calling <a href="ft2-base_interface.html#FT_Render_Glyph">FT_Render_Glyph</a>. This function finds the current renderer for the native image's format, then invokes it.</p>
<p>The renderer is in charge of transforming the native image through the slot's face transformation fields, then converting it into a bitmap that is returned in &lsquo;slot-&gt;bitmap&rsquo;.</p>
<p>Note that &lsquo;slot-&gt;bitmap_left&rsquo; and &lsquo;slot-&gt;bitmap_top&rsquo; are also used to specify the position of the bitmap relative to the current pen position (e.g., coordinates (0,0) on the baseline). Of course, &lsquo;slot-&gt;format&rsquo; is also changed to <a href="ft2-basic_types.html#FT_Glyph_Format">FT_GLYPH_FORMAT_BITMAP</a>.</p>
<h4>note</h4>
<p>Here is a small pseudo code fragment that shows how to use &lsquo;lsb_delta&rsquo; and &lsquo;rsb_delta&rsquo;:</p>
<pre class="colored">
FT_Pos origin_x = 0;
FT_Pos prev_rsb_delta = 0;
for all glyphs do
&lt;compute kern between current and previous glyph and add it to
`origin_x'&gt;
&lt;load glyph with `FT_Load_Glyph'&gt;
if ( prev_rsb_delta - face-&gt;glyph-&gt;lsb_delta &gt;= 32 )
origin_x -= 64;
else if ( prev_rsb_delta - face-&gt;glyph-&gt;lsb_delta &lt; -32 )
origin_x += 64;
prev_rsb_delta = face-&gt;glyph-&gt;rsb_delta;
&lt;save glyph image, or render glyph, or ...&gt;
origin_x += face-&gt;glyph-&gt;advance.x;
endfor
</pre>
<hr>
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<div class="section">
<h3 id="FT_Glyph_Metrics">FT_Glyph_Metrics</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Glyph_Metrics_
{
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> width;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> height;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> horiBearingX;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> horiBearingY;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> horiAdvance;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> vertBearingX;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> vertBearingY;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> vertAdvance;
} <b>FT_Glyph_Metrics</b>;
</pre>
<p>A structure used to model the metrics of a single glyph. The values are expressed in 26.6 fractional pixel format; if the flag <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_NO_SCALE</a> has been used while loading the glyph, values are expressed in font units instead.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="width">width</td><td class="desc">
<p>The glyph's width.</p>
</td></tr>
<tr><td class="val" id="height">height</td><td class="desc">
<p>The glyph's height.</p>
</td></tr>
<tr><td class="val" id="horiBearingX">horiBearingX</td><td class="desc">
<p>Left side bearing for horizontal layout.</p>
</td></tr>
<tr><td class="val" id="horiBearingY">horiBearingY</td><td class="desc">
<p>Top side bearing for horizontal layout.</p>
</td></tr>
<tr><td class="val" id="horiAdvance">horiAdvance</td><td class="desc">
<p>Advance width for horizontal layout.</p>
</td></tr>
<tr><td class="val" id="vertBearingX">vertBearingX</td><td class="desc">
<p>Left side bearing for vertical layout.</p>
</td></tr>
<tr><td class="val" id="vertBearingY">vertBearingY</td><td class="desc">
<p>Top side bearing for vertical layout. Larger positive values mean further below the vertical glyph origin.</p>
</td></tr>
<tr><td class="val" id="vertAdvance">vertAdvance</td><td class="desc">
<p>Advance height for vertical layout. Positive values mean the glyph has a positive advance downward.</p>
</td></tr>
</table>
<h4>note</h4>
<p>If not disabled with <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_NO_HINTING</a>, the values represent dimensions of the hinted glyph (in case hinting is applicable).</p>
<p>Stroking a glyph with an outside border does not increase &lsquo;horiAdvance&rsquo; or &lsquo;vertAdvance&rsquo;; you have to manually adjust these values to account for the added width and height.</p>
<hr>
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<div class="section">
<h3 id="FT_SubGlyph">FT_SubGlyph</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_SubGlyphRec_* <b>FT_SubGlyph</b>;
</pre>
<p>The subglyph structure is an internal object used to describe subglyphs (for example, in the case of composites).</p>
<h4>note</h4>
<p>The subglyph implementation is not part of the high-level API, hence the forward structure declaration.</p>
<p>You can however retrieve subglyph information with <a href="ft2-base_interface.html#FT_Get_SubGlyph_Info">FT_Get_SubGlyph_Info</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_Bitmap_Size">FT_Bitmap_Size</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Bitmap_Size_
{
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> height;
<a href="ft2-basic_types.html#FT_Short">FT_Short</a> width;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> size;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> x_ppem;
<a href="ft2-basic_types.html#FT_Pos">FT_Pos</a> y_ppem;
} <b>FT_Bitmap_Size</b>;
</pre>
<p>This structure models the metrics of a bitmap strike (i.e., a set of glyphs for a given point size and resolution) in a bitmap font. It is used for the &lsquo;available_sizes&rsquo; field of <a href="ft2-base_interface.html#FT_Face">FT_Face</a>.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="height">height</td><td class="desc">
<p>The vertical distance, in pixels, between two consecutive baselines. It is always positive.</p>
</td></tr>
<tr><td class="val" id="width">width</td><td class="desc">
<p>The average width, in pixels, of all glyphs in the strike.</p>
</td></tr>
<tr><td class="val" id="size">size</td><td class="desc">
<p>The nominal size of the strike in 26.6 fractional points. This field is not very useful.</p>
</td></tr>
<tr><td class="val" id="x_ppem">x_ppem</td><td class="desc">
<p>The horizontal ppem (nominal width) in 26.6 fractional pixels.</p>
</td></tr>
<tr><td class="val" id="y_ppem">y_ppem</td><td class="desc">
<p>The vertical ppem (nominal height) in 26.6 fractional pixels.</p>
</td></tr>
</table>
<h4>note</h4>
<p>Windows FNT: The nominal size given in a FNT font is not reliable. Thus when the driver finds it incorrect, it sets &lsquo;size&rsquo; to some calculated values and sets &lsquo;x_ppem&rsquo; and &lsquo;y_ppem&rsquo; to the pixel width and height given in the font, respectively.</p>
<p>TrueType embedded bitmaps: &lsquo;size&rsquo;, &lsquo;width&rsquo;, and &lsquo;height&rsquo; values are not contained in the bitmap strike itself. They are computed from the global font parameters.</p>
<hr>
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<div class="section">
<h3 id="FT_Init_FreeType">FT_Init_FreeType</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Init_FreeType</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a> *alibrary );
</pre>
<p>Initialize a new FreeType library object. The set of modules that are registered by this function is determined at build time.</p>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="alibrary">alibrary</td><td class="desc">
<p>A handle to a new library object.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>In case you want to provide your own memory allocating routines, use <a href="ft2-module_management.html#FT_New_Library">FT_New_Library</a> instead, followed by a call to <a href="ft2-module_management.html#FT_Add_Default_Modules">FT_Add_Default_Modules</a> (or a series of calls to <a href="ft2-module_management.html#FT_Add_Module">FT_Add_Module</a>).</p>
<p>See the documentation of <a href="ft2-base_interface.html#FT_Library">FT_Library</a> and <a href="ft2-base_interface.html#FT_Face">FT_Face</a> for multi-threading issues.</p>
<p>If you need reference-counting (cf. <a href="ft2-module_management.html#FT_Reference_Library">FT_Reference_Library</a>), use <a href="ft2-module_management.html#FT_New_Library">FT_New_Library</a> and <a href="ft2-module_management.html#FT_Done_Library">FT_Done_Library</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_Done_FreeType">FT_Done_FreeType</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Done_FreeType</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a> library );
</pre>
<p>Destroy a given FreeType library object and all of its children, including resources, drivers, faces, sizes, etc.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to the target library object.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<hr>
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<div class="section">
<h3 id="FT_New_Face">FT_New_Face</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_New_Face</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a> library,
<span class="keyword">const</span> <span class="keyword">char</span>* filepathname,
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> face_index,
<a href="ft2-base_interface.html#FT_Face">FT_Face</a> *aface );
</pre>
<p>This function calls <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> to open a font by its pathname.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to the library resource.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="pathname">pathname</td><td class="desc">
<p>A path to the font file.</p>
</td></tr>
<tr><td class="val" id="face_index">face_index</td><td class="desc">
<p>See <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> for a detailed description of this parameter.</p>
</td></tr>
</table>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="aface">aface</td><td class="desc">
<p>A handle to a new face object. If &lsquo;face_index&rsquo; is greater than or equal to zero, it must be non-NULL.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>Use <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a> to destroy the created <a href="ft2-base_interface.html#FT_Face">FT_Face</a> object (along with its slot and sizes).</p>
<hr>
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<div class="section">
<h3 id="FT_Done_Face">FT_Done_Face</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Done_Face</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face );
</pre>
<p>Discard a given face object, as well as all of its child slots and sizes.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a target face object.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>See the discussion of reference counters in the description of <a href="ft2-base_interface.html#FT_Reference_Face">FT_Reference_Face</a>.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Reference_Face">FT_Reference_Face</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Reference_Face</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face );
</pre>
<p>A counter gets initialized to&nbsp;1 at the time an <a href="ft2-base_interface.html#FT_Face">FT_Face</a> structure is created. This function increments the counter. <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a> then only destroys a face if the counter is&nbsp;1, otherwise it simply decrements the counter.</p>
<p>This function helps in managing life-cycles of structures that reference <a href="ft2-base_interface.html#FT_Face">FT_Face</a> objects.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a target face object.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>since</h4>
<p>2.4.2</p>
<hr>
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<div class="section">
<h3 id="FT_New_Memory_Face">FT_New_Memory_Face</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_New_Memory_Face</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a> library,
<span class="keyword">const</span> <a href="ft2-basic_types.html#FT_Byte">FT_Byte</a>* file_base,
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> file_size,
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> face_index,
<a href="ft2-base_interface.html#FT_Face">FT_Face</a> *aface );
</pre>
<p>This function calls <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> to open a font that has been loaded into memory.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to the library resource.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="file_base">file_base</td><td class="desc">
<p>A pointer to the beginning of the font data.</p>
</td></tr>
<tr><td class="val" id="file_size">file_size</td><td class="desc">
<p>The size of the memory chunk used by the font data.</p>
</td></tr>
<tr><td class="val" id="face_index">face_index</td><td class="desc">
<p>See <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> for a detailed description of this parameter.</p>
</td></tr>
</table>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="aface">aface</td><td class="desc">
<p>A handle to a new face object. If &lsquo;face_index&rsquo; is greater than or equal to zero, it must be non-NULL.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>You must not deallocate the memory before calling <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_Open_Face">FT_Open_Face</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Open_Face</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a> library,
<span class="keyword">const</span> <a href="ft2-base_interface.html#FT_Open_Args">FT_Open_Args</a>* args,
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> face_index,
<a href="ft2-base_interface.html#FT_Face">FT_Face</a> *aface );
</pre>
<p>Create a face object from a given resource described by <a href="ft2-base_interface.html#FT_Open_Args">FT_Open_Args</a>.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to the library resource.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="args">args</td><td class="desc">
<p>A pointer to an &lsquo;FT_Open_Args&rsquo; structure that must be filled by the caller.</p>
</td></tr>
<tr><td class="val" id="face_index">face_index</td><td class="desc">
<p>This field holds two different values. Bits 0-15 are the index of the face in the font file (starting with value&nbsp;0). Set it to&nbsp;0 if there is only one face in the font file.</p>
<p>Bits 16-30 are relevant to GX variation fonts only, specifying the named instance index for the current face index (starting with value&nbsp;1; value&nbsp;0 makes FreeType ignore named instances). For non-GX fonts, bits 16-30 are ignored. Assuming that you want to access the third named instance in face&nbsp;4, &lsquo;face_index&rsquo; should be set to 0x00030004. If you want to access face&nbsp;4 without GX variation handling, simply set &lsquo;face_index&rsquo; to value&nbsp;4.</p>
<p>FT_Open_Face and its siblings can be used to quickly check whether the font format of a given font resource is supported by FreeType. In general, if the &lsquo;face_index&rsquo; argument is negative, the function's return value is&nbsp;0 if the font format is recognized, or non-zero otherwise. The function allocates a more or less empty face handle in &lsquo;*aface&rsquo; (if &lsquo;aface&rsquo; isn't NULL); the only two useful fields in this special case are &lsquo;face-&gt;num_faces&rsquo; and &lsquo;face-&gt;style_flags&rsquo;. For any negative value of &lsquo;face_index&rsquo;, &lsquo;face-&gt;num_faces&rsquo; gives the number of faces within the font file. For the negative value &lsquo;-(N+1)&rsquo; (with &lsquo;N&rsquo; a 16-bit value), bits 16-30 in &lsquo;face-&gt;style_flags&rsquo; give the number of named instances in face &lsquo;N&rsquo; if we have a GX variation font (or zero otherwise). After examination, the returned <a href="ft2-base_interface.html#FT_Face">FT_Face</a> structure should be deallocated with a call to <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a>.</p>
</td></tr>
</table>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="aface">aface</td><td class="desc">
<p>A handle to a new face object. If &lsquo;face_index&rsquo; is greater than or equal to zero, it must be non-NULL.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>Unlike FreeType 1.x, this function automatically creates a glyph slot for the face object that can be accessed directly through &lsquo;face-&gt;glyph&rsquo;.</p>
<p>Each new face object created with this function also owns a default <a href="ft2-base_interface.html#FT_Size">FT_Size</a> object, accessible as &lsquo;face-&gt;size&rsquo;.</p>
<p>One <a href="ft2-base_interface.html#FT_Library">FT_Library</a> instance can have multiple face objects, this is, <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> and its siblings can be called multiple times using the same &lsquo;library&rsquo; argument.</p>
<p>See the discussion of reference counters in the description of <a href="ft2-base_interface.html#FT_Reference_Face">FT_Reference_Face</a>.</p>
<p>To loop over all faces, use code similar to the following snippet (omitting the error handling).</p>
<pre class="colored">
...
FT_Face face;
FT_Long i, num_faces;
error = FT_Open_Face( library, args, -1, &amp;face );
if ( error ) { ... }
num_faces = face-&gt;num_faces;
FT_Done_Face( face );
for ( i = 0; i &lt; num_faces; i++ )
{
...
error = FT_Open_Face( library, args, i, &amp;face );
...
FT_Done_Face( face );
...
}
</pre>
<p>To loop over all valid values for &lsquo;face_index&rsquo;, use something similar to the following snippet, again without error handling. The code accesses all faces immediately (thus only a single call of &lsquo;FT_Open_Face&rsquo; within the do-loop), with and without named instances.</p>
<pre class="colored">
...
FT_Face face;
FT_Long num_faces = 0;
FT_Long num_instances = 0;
FT_Long face_idx = 0;
FT_Long instance_idx = 0;
do
{
FT_Long id = ( instance_idx &lt;&lt; 16 ) + face_idx;
error = FT_Open_Face( library, args, id, &amp;face );
if ( error ) { ... }
num_faces = face-&gt;num_faces;
num_instances = face-&gt;style_flags &gt;&gt; 16;
...
FT_Done_Face( face );
if ( instance_idx &lt; num_instances )
instance_idx++;
else
{
face_idx++;
instance_idx = 0;
}
} while ( face_idx &lt; num_faces )
</pre>
<hr>
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<div class="section">
<h3 id="FT_Open_Args">FT_Open_Args</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Open_Args_
{
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> flags;
<span class="keyword">const</span> <a href="ft2-basic_types.html#FT_Byte">FT_Byte</a>* memory_base;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> memory_size;
<a href="ft2-basic_types.html#FT_String">FT_String</a>* pathname;
<a href="ft2-system_interface.html#FT_Stream">FT_Stream</a> stream;
<a href="ft2-module_management.html#FT_Module">FT_Module</a> driver;
<a href="ft2-basic_types.html#FT_Int">FT_Int</a> num_params;
<a href="ft2-base_interface.html#FT_Parameter">FT_Parameter</a>* params;
} <b>FT_Open_Args</b>;
</pre>
<p>A structure used to indicate how to open a new font file or stream. A pointer to such a structure can be used as a parameter for the functions <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> and <a href="ft2-base_interface.html#FT_Attach_Stream">FT_Attach_Stream</a>.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="flags">flags</td><td class="desc">
<p>A set of bit flags indicating how to use the structure.</p>
</td></tr>
<tr><td class="val" id="memory_base">memory_base</td><td class="desc">
<p>The first byte of the file in memory.</p>
</td></tr>
<tr><td class="val" id="memory_size">memory_size</td><td class="desc">
<p>The size in bytes of the file in memory.</p>
</td></tr>
<tr><td class="val" id="pathname">pathname</td><td class="desc">
<p>A pointer to an 8-bit file pathname.</p>
</td></tr>
<tr><td class="val" id="stream">stream</td><td class="desc">
<p>A handle to a source stream object.</p>
</td></tr>
<tr><td class="val" id="driver">driver</td><td class="desc">
<p>This field is exclusively used by <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a>; it simply specifies the font driver to use to open the face. If set to&nbsp;0, FreeType tries to load the face with each one of the drivers in its list.</p>
</td></tr>
<tr><td class="val" id="num_params">num_params</td><td class="desc">
<p>The number of extra parameters.</p>
</td></tr>
<tr><td class="val" id="params">params</td><td class="desc">
<p>Extra parameters passed to the font driver when opening a new face.</p>
</td></tr>
</table>
<h4>note</h4>
<p>The stream type is determined by the contents of &lsquo;flags&rsquo; that are tested in the following order by <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a>:</p>
<p>If the <a href="ft2-base_interface.html#FT_OPEN_XXX">FT_OPEN_MEMORY</a> bit is set, assume that this is a memory file of &lsquo;memory_size&rsquo; bytes, located at &lsquo;memory_address&rsquo;. The data are are not copied, and the client is responsible for releasing and destroying them <i>after</i> the corresponding call to <a href="ft2-base_interface.html#FT_Done_Face">FT_Done_Face</a>.</p>
<p>Otherwise, if the <a href="ft2-base_interface.html#FT_OPEN_XXX">FT_OPEN_STREAM</a> bit is set, assume that a custom input stream &lsquo;stream&rsquo; is used.</p>
<p>Otherwise, if the <a href="ft2-base_interface.html#FT_OPEN_XXX">FT_OPEN_PATHNAME</a> bit is set, assume that this is a normal file and use &lsquo;pathname&rsquo; to open it.</p>
<p>If the <a href="ft2-base_interface.html#FT_OPEN_XXX">FT_OPEN_DRIVER</a> bit is set, <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a> only tries to open the file with the driver whose handler is in &lsquo;driver&rsquo;.</p>
<p>If the <a href="ft2-base_interface.html#FT_OPEN_XXX">FT_OPEN_PARAMS</a> bit is set, the parameters given by &lsquo;num_params&rsquo; and &lsquo;params&rsquo; is used. They are ignored otherwise.</p>
<p>Ideally, both the &lsquo;pathname&rsquo; and &lsquo;params&rsquo; fields should be tagged as &lsquo;const&rsquo;; this is missing for API backwards compatibility. In other words, applications should treat them as read-only.</p>
<hr>
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<div class="section">
<h3 id="FT_Parameter">FT_Parameter</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Parameter_
{
<a href="ft2-basic_types.html#FT_ULong">FT_ULong</a> tag;
<a href="ft2-basic_types.html#FT_Pointer">FT_Pointer</a> data;
} <b>FT_Parameter</b>;
</pre>
<p>A simple structure used to pass more or less generic parameters to <a href="ft2-base_interface.html#FT_Open_Face">FT_Open_Face</a>.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="tag">tag</td><td class="desc">
<p>A four-byte identification tag.</p>
</td></tr>
<tr><td class="val" id="data">data</td><td class="desc">
<p>A pointer to the parameter data.</p>
</td></tr>
</table>
<h4>note</h4>
<p>The ID and function of parameters are driver-specific. See the various FT_PARAM_TAG_XXX flags for more information.</p>
<hr>
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<div class="section">
<h3 id="FT_Attach_File">FT_Attach_File</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Attach_File</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<span class="keyword">const</span> <span class="keyword">char</span>* filepathname );
</pre>
<p>This function calls <a href="ft2-base_interface.html#FT_Attach_Stream">FT_Attach_Stream</a> to attach a file.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>The target face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="filepathname">filepathname</td><td class="desc">
<p>The pathname.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<hr>
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<div class="section">
<h3 id="FT_Attach_Stream">FT_Attach_Stream</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Attach_Stream</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-base_interface.html#FT_Open_Args">FT_Open_Args</a>* parameters );
</pre>
<p>&lsquo;Attach&rsquo; data to a face object. Normally, this is used to read additional information for the face object. For example, you can attach an AFM file that comes with a Type&nbsp;1 font to get the kerning values and other metrics.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>The target face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="parameters">parameters</td><td class="desc">
<p>A pointer to <a href="ft2-base_interface.html#FT_Open_Args">FT_Open_Args</a> that must be filled by the caller.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>The meaning of the &lsquo;attach&rsquo; (i.e., what really happens when the new file is read) is not fixed by FreeType itself. It really depends on the font format (and thus the font driver).</p>
<p>Client applications are expected to know what they are doing when invoking this function. Most drivers simply do not implement file attachments.</p>
<hr>
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<div class="section">
<h3 id="FT_Set_Char_Size">FT_Set_Char_Size</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Set_Char_Size</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_F26Dot6">FT_F26Dot6</a> char_width,
<a href="ft2-basic_types.html#FT_F26Dot6">FT_F26Dot6</a> char_height,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> horz_resolution,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> vert_resolution );
</pre>
<p>This function calls <a href="ft2-base_interface.html#FT_Request_Size">FT_Request_Size</a> to request the nominal size (in points).</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a target face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="char_width">char_width</td><td class="desc">
<p>The nominal width, in 26.6 fractional points.</p>
</td></tr>
<tr><td class="val" id="char_height">char_height</td><td class="desc">
<p>The nominal height, in 26.6 fractional points.</p>
</td></tr>
<tr><td class="val" id="horz_resolution">horz_resolution</td><td class="desc">
<p>The horizontal resolution in dpi.</p>
</td></tr>
<tr><td class="val" id="vert_resolution">vert_resolution</td><td class="desc">
<p>The vertical resolution in dpi.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>If either the character width or height is zero, it is set equal to the other value.</p>
<p>If either the horizontal or vertical resolution is zero, it is set equal to the other value.</p>
<p>A character width or height smaller than 1pt is set to 1pt; if both resolution values are zero, they are set to 72dpi.</p>
<p>Don't use this function if you are using the FreeType cache API.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Set_Pixel_Sizes">FT_Set_Pixel_Sizes</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Set_Pixel_Sizes</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> pixel_width,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> pixel_height );
</pre>
<p>This function calls <a href="ft2-base_interface.html#FT_Request_Size">FT_Request_Size</a> to request the nominal size (in pixels).</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the target face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="pixel_width">pixel_width</td><td class="desc">
<p>The nominal width, in pixels.</p>
</td></tr>
<tr><td class="val" id="pixel_height">pixel_height</td><td class="desc">
<p>The nominal height, in pixels.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>You should not rely on the resulting glyphs matching, or being constrained, to this pixel size. Refer to <a href="ft2-base_interface.html#FT_Request_Size">FT_Request_Size</a> to understand how requested sizes relate to actual sizes.</p>
<p>Don't use this function if you are using the FreeType cache API.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Request_Size">FT_Request_Size</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Request_Size</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-base_interface.html#FT_Size_Request">FT_Size_Request</a> req );
</pre>
<p>Resize the scale of the active <a href="ft2-base_interface.html#FT_Size">FT_Size</a> object in a face.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a target face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="req">req</td><td class="desc">
<p>A pointer to a <a href="ft2-base_interface.html#FT_Size_RequestRec">FT_Size_RequestRec</a>.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>Although drivers may select the bitmap strike matching the request, you should not rely on this if you intend to select a particular bitmap strike. Use <a href="ft2-base_interface.html#FT_Select_Size">FT_Select_Size</a> instead in that case.</p>
<p>The relation between the requested size and the resulting glyph size is dependent entirely on how the size is defined in the source face. The font designer chooses the final size of each glyph relative to this size. For more information refer to &lsquo;<a href="http://www.freetype.org/freetype2/docs/glyphs/glyphs-2.html">http://www.freetype.org/freetype2/docs/glyphs/glyphs-2.html</a>&rsquo;</p>
<p>Don't use this function if you are using the FreeType cache API.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Select_Size">FT_Select_Size</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Select_Size</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_Int">FT_Int</a> strike_index );
</pre>
<p>Select a bitmap strike.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a target face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="strike_index">strike_index</td><td class="desc">
<p>The index of the bitmap strike in the &lsquo;available_sizes&rsquo; field of <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> structure.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Size_Request_Type">FT_Size_Request_Type</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">enum</span> FT_Size_Request_Type_
{
<a href="ft2-base_interface.html#FT_SIZE_REQUEST_TYPE_NOMINAL">FT_SIZE_REQUEST_TYPE_NOMINAL</a>,
<a href="ft2-base_interface.html#FT_SIZE_REQUEST_TYPE_REAL_DIM">FT_SIZE_REQUEST_TYPE_REAL_DIM</a>,
<a href="ft2-base_interface.html#FT_SIZE_REQUEST_TYPE_BBOX">FT_SIZE_REQUEST_TYPE_BBOX</a>,
<a href="ft2-base_interface.html#FT_SIZE_REQUEST_TYPE_CELL">FT_SIZE_REQUEST_TYPE_CELL</a>,
<a href="ft2-base_interface.html#FT_SIZE_REQUEST_TYPE_SCALES">FT_SIZE_REQUEST_TYPE_SCALES</a>,
FT_SIZE_REQUEST_TYPE_MAX
} <b>FT_Size_Request_Type</b>;
</pre>
<p>An enumeration type that lists the supported size request types.</p>
<h4>values</h4>
<table class="fields">
<tr><td class="val" id="FT_SIZE_REQUEST_TYPE_NOMINAL">FT_SIZE_REQUEST_TYPE_NOMINAL</td><td class="desc">
<p>The nominal size. The &lsquo;units_per_EM&rsquo; field of <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> is used to determine both scaling values.</p>
</td></tr>
<tr><td class="val" id="FT_SIZE_REQUEST_TYPE_REAL_DIM">FT_SIZE_REQUEST_TYPE_REAL_DIM</td><td class="desc">
<p>The real dimension. The sum of the the &lsquo;ascender&rsquo; and (minus of) the &lsquo;descender&rsquo; fields of <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> are used to determine both scaling values.</p>
</td></tr>
<tr><td class="val" id="FT_SIZE_REQUEST_TYPE_BBOX">FT_SIZE_REQUEST_TYPE_BBOX</td><td class="desc">
<p>The font bounding box. The width and height of the &lsquo;bbox&rsquo; field of <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> are used to determine the horizontal and vertical scaling value, respectively.</p>
</td></tr>
<tr><td class="val" id="FT_SIZE_REQUEST_TYPE_CELL">FT_SIZE_REQUEST_TYPE_CELL</td><td class="desc">
<p>The &lsquo;max_advance_width&rsquo; field of <a href="ft2-base_interface.html#FT_FaceRec">FT_FaceRec</a> is used to determine the horizontal scaling value; the vertical scaling value is determined the same way as <a href="ft2-base_interface.html#FT_Size_Request_Type">FT_SIZE_REQUEST_TYPE_REAL_DIM</a> does. Finally, both scaling values are set to the smaller one. This type is useful if you want to specify the font size for, say, a window of a given dimension and 80x24 cells.</p>
</td></tr>
<tr><td class="val" id="FT_SIZE_REQUEST_TYPE_SCALES">FT_SIZE_REQUEST_TYPE_SCALES</td><td class="desc">
<p>Specify the scaling values directly.</p>
</td></tr>
</table>
<h4>note</h4>
<p>The above descriptions only apply to scalable formats. For bitmap formats, the behaviour is up to the driver.</p>
<p>See the note section of <a href="ft2-base_interface.html#FT_Size_Metrics">FT_Size_Metrics</a> if you wonder how size requesting relates to scaling values.</p>
<hr>
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<div class="section">
<h3 id="FT_Size_RequestRec">FT_Size_RequestRec</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Size_RequestRec_
{
<a href="ft2-base_interface.html#FT_Size_Request_Type">FT_Size_Request_Type</a> type;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> width;
<a href="ft2-basic_types.html#FT_Long">FT_Long</a> height;
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> horiResolution;
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> vertResolution;
} <b>FT_Size_RequestRec</b>;
</pre>
<p>A structure used to model a size request.</p>
<h4>fields</h4>
<table class="fields">
<tr><td class="val" id="type">type</td><td class="desc">
<p>See <a href="ft2-base_interface.html#FT_Size_Request_Type">FT_Size_Request_Type</a>.</p>
</td></tr>
<tr><td class="val" id="width">width</td><td class="desc">
<p>The desired width.</p>
</td></tr>
<tr><td class="val" id="height">height</td><td class="desc">
<p>The desired height.</p>
</td></tr>
<tr><td class="val" id="horiResolution">horiResolution</td><td class="desc">
<p>The horizontal resolution. If set to zero, &lsquo;width&rsquo; is treated as a 26.6 fractional pixel value.</p>
</td></tr>
<tr><td class="val" id="vertResolution">vertResolution</td><td class="desc">
<p>The vertical resolution. If set to zero, &lsquo;height&rsquo; is treated as a 26.6 fractional pixel value.</p>
</td></tr>
</table>
<h4>note</h4>
<p>If &lsquo;width&rsquo; is zero, then the horizontal scaling value is set equal to the vertical scaling value, and vice versa.</p>
<hr>
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<div class="section">
<h3 id="FT_Size_Request">FT_Size_Request</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_Size_RequestRec_ *<b>FT_Size_Request</b>;
</pre>
<p>A handle to a size request structure.</p>
<hr>
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<div class="section">
<h3 id="FT_Set_Transform">FT_Set_Transform</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <span class="keyword">void</span> )
<b>FT_Set_Transform</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_Matrix">FT_Matrix</a>* matrix,
<a href="ft2-basic_types.html#FT_Vector">FT_Vector</a>* delta );
</pre>
<p>A function used to set the transformation that is applied to glyph images when they are loaded into a glyph slot through <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a>.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the source face object.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="matrix">matrix</td><td class="desc">
<p>A pointer to the transformation's 2x2 matrix. Use&nbsp;0 for the identity matrix.</p>
</td></tr>
<tr><td class="val" id="delta">delta</td><td class="desc">
<p>A pointer to the translation vector. Use&nbsp;0 for the null vector.</p>
</td></tr>
</table>
<h4>note</h4>
<p>The transformation is only applied to scalable image formats after the glyph has been loaded. It means that hinting is unaltered by the transformation and is performed on the character size given in the last call to <a href="ft2-base_interface.html#FT_Set_Char_Size">FT_Set_Char_Size</a> or <a href="ft2-base_interface.html#FT_Set_Pixel_Sizes">FT_Set_Pixel_Sizes</a>.</p>
<p>Note that this also transforms the &lsquo;face.glyph.advance&rsquo; field, but <b>not</b> the values in &lsquo;face.glyph.metrics&rsquo;.</p>
<hr>
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<div class="section">
<h3 id="FT_Load_Glyph">FT_Load_Glyph</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Load_Glyph</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> glyph_index,
<a href="ft2-basic_types.html#FT_Int32">FT_Int32</a> load_flags );
</pre>
<p>A function used to load a single glyph into the glyph slot of a face object.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the target face object where the glyph is loaded.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="glyph_index">glyph_index</td><td class="desc">
<p>The index of the glyph in the font file. For CID-keyed fonts (either in PS or in CFF format) this argument specifies the CID value.</p>
</td></tr>
<tr><td class="val" id="load_flags">load_flags</td><td class="desc">
<p>A flag indicating what to load for this glyph. The <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_XXX</a> constants can be used to control the glyph loading process (e.g., whether the outline should be scaled, whether to load bitmaps or not, whether to hint the outline, etc).</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>The loaded glyph may be transformed. See <a href="ft2-base_interface.html#FT_Set_Transform">FT_Set_Transform</a> for the details.</p>
<p>For subsetted CID-keyed fonts, &lsquo;FT_Err_Invalid_Argument&rsquo; is returned for invalid CID values (this is, for CID values that don't have a corresponding glyph in the font). See the discussion of the <a href="ft2-base_interface.html#FT_FACE_FLAG_XXX">FT_FACE_FLAG_CID_KEYED</a> flag for more details.</p>
<hr>
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<div class="section">
<h3 id="FT_Get_Char_Index">FT_Get_Char_Index</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> )
<b>FT_Get_Char_Index</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_ULong">FT_ULong</a> charcode );
</pre>
<p>Return the glyph index of a given character code. This function uses a charmap object to do the mapping.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the source face object.</p>
</td></tr>
<tr><td class="val" id="charcode">charcode</td><td class="desc">
<p>The character code.</p>
</td></tr>
</table>
<h4>return</h4>
<p>The glyph index. 0&nbsp;means &lsquo;undefined character code&rsquo;.</p>
<h4>note</h4>
<p>If you use FreeType to manipulate the contents of font files directly, be aware that the glyph index returned by this function doesn't always correspond to the internal indices used within the file. This is done to ensure that value&nbsp;0 always corresponds to the &lsquo;missing glyph&rsquo;. If the first glyph is not named &lsquo;.notdef&rsquo;, then for Type&nbsp;1 and Type&nbsp;42 fonts, &lsquo;.notdef&rsquo; will be moved into the glyph ID&nbsp;0 position, and whatever was there will be moved to the position &lsquo;.notdef&rsquo; had. For Type&nbsp;1 fonts, if there is no &lsquo;.notdef&rsquo; glyph at all, then one will be created at index&nbsp;0 and whatever was there will be moved to the last index -- Type&nbsp;42 fonts are considered invalid under this condition.</p>
<hr>
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<div class="section">
<h3 id="FT_Get_First_Char">FT_Get_First_Char</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_ULong">FT_ULong</a> )
<b>FT_Get_First_Char</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> *agindex );
</pre>
<p>This function is used to return the first character code in the current charmap of a given face. It also returns the corresponding glyph index.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the source face object.</p>
</td></tr>
</table>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="agindex">agindex</td><td class="desc">
<p>Glyph index of first character code. 0&nbsp;if charmap is empty.</p>
</td></tr>
</table>
<h4>return</h4>
<p>The charmap's first character code.</p>
<h4>note</h4>
<p>You should use this function with <a href="ft2-base_interface.html#FT_Get_Next_Char">FT_Get_Next_Char</a> to be able to parse all character codes available in a given charmap. The code should look like this:</p>
<pre class="colored">
FT_ULong charcode;
FT_UInt gindex;
charcode = FT_Get_First_Char( face, &amp;gindex );
while ( gindex != 0 )
{
... do something with (charcode,gindex) pair ...
charcode = FT_Get_Next_Char( face, charcode, &amp;gindex );
}
</pre>
<p>Be aware that character codes can have values up to 0xFFFFFFFF; this might happen for non-Unicode or malformed cmaps. However, even with regular Unicode encoding, so-called &lsquo;last resort fonts&rsquo; (using SFNT cmap format 13, see function <a href="ft2-truetype_tables.html#FT_Get_CMap_Format">FT_Get_CMap_Format</a>) normally have entries for all Unicode characters up to 0x1FFFFF, which can cause *a lot* of iterations.</p>
<p>Note that &lsquo;*agindex&rsquo; is set to&nbsp;0 if the charmap is empty. The result itself can be&nbsp;0 in two cases: if the charmap is empty or if the value&nbsp;0 is the first valid character code.</p>
<hr>
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<div class="section">
<h3 id="FT_Get_Next_Char">FT_Get_Next_Char</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_ULong">FT_ULong</a> )
<b>FT_Get_Next_Char</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_ULong">FT_ULong</a> char_code,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> *agindex );
</pre>
<p>This function is used to return the next character code in the current charmap of a given face following the value &lsquo;char_code&rsquo;, as well as the corresponding glyph index.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the source face object.</p>
</td></tr>
<tr><td class="val" id="char_code">char_code</td><td class="desc">
<p>The starting character code.</p>
</td></tr>
</table>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="agindex">agindex</td><td class="desc">
<p>Glyph index of next character code. 0&nbsp;if charmap is empty.</p>
</td></tr>
</table>
<h4>return</h4>
<p>The charmap's next character code.</p>
<h4>note</h4>
<p>You should use this function with <a href="ft2-base_interface.html#FT_Get_First_Char">FT_Get_First_Char</a> to walk over all character codes available in a given charmap. See the note for this function for a simple code example.</p>
<p>Note that &lsquo;*agindex&rsquo; is set to&nbsp;0 when there are no more codes in the charmap.</p>
<hr>
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<div class="section">
<h3 id="FT_Get_Name_Index">FT_Get_Name_Index</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> )
<b>FT_Get_Name_Index</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_String">FT_String</a>* glyph_name );
</pre>
<p>Return the glyph index of a given glyph name. This function uses driver specific objects to do the translation.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the source face object.</p>
</td></tr>
<tr><td class="val" id="glyph_name">glyph_name</td><td class="desc">
<p>The glyph name.</p>
</td></tr>
</table>
<h4>return</h4>
<p>The glyph index. 0&nbsp;means &lsquo;undefined character code&rsquo;.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Load_Char">FT_Load_Char</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Load_Char</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_ULong">FT_ULong</a> char_code,
<a href="ft2-basic_types.html#FT_Int32">FT_Int32</a> load_flags );
</pre>
<p>A function used to load a single glyph into the glyph slot of a face object, according to its character code.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a target face object where the glyph is loaded.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="char_code">char_code</td><td class="desc">
<p>The glyph's character code, according to the current charmap used in the face.</p>
</td></tr>
<tr><td class="val" id="load_flags">load_flags</td><td class="desc">
<p>A flag indicating what to load for this glyph. The <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_XXX</a> constants can be used to control the glyph loading process (e.g., whether the outline should be scaled, whether to load bitmaps or not, whether to hint the outline, etc).</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>This function simply calls <a href="ft2-base_interface.html#FT_Get_Char_Index">FT_Get_Char_Index</a> and <a href="ft2-base_interface.html#FT_Load_Glyph">FT_Load_Glyph</a>.</p>
<hr>
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<div class="section">
<h3 id="FT_LOAD_TARGET_MODE">FT_LOAD_TARGET_MODE</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
#define <b>FT_LOAD_TARGET_MODE</b>( x ) ( (<a href="ft2-base_interface.html#FT_Render_Mode">FT_Render_Mode</a>)( ( (x) &gt;&gt; 16 ) &amp; 15 ) )
</pre>
<p>Return the <a href="ft2-base_interface.html#FT_Render_Mode">FT_Render_Mode</a> corresponding to a given <a href="ft2-base_interface.html#FT_LOAD_TARGET_XXX">FT_LOAD_TARGET_XXX</a> value.</p>
<hr>
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<div class="section">
<h3 id="FT_Render_Glyph">FT_Render_Glyph</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Render_Glyph</b>( <a href="ft2-base_interface.html#FT_GlyphSlot">FT_GlyphSlot</a> slot,
<a href="ft2-base_interface.html#FT_Render_Mode">FT_Render_Mode</a> render_mode );
</pre>
<p>Convert a given glyph image to a bitmap. It does so by inspecting the glyph image format, finding the relevant renderer, and invoking it.</p>
<p>When FreeType outputs a bitmap of a glyph, it really outputs an alpha coverage map. If a pixel is completely covered by a filled-in outline, the bitmap contains 0xFF at that pixel, meaning that 0xFF/0xFF fraction of that pixel is covered, meaning the pixel is 100% black (or 0% bright). If a pixel is only 50% covered (value 0x80), the pixel is made 50% black (50% bright or a middle shade of grey). 0% covered means 0% black (100% bright or white).</p>
<p>On high-DPI screens like on smartphones and tablets, the pixels are so small that their chance of being completely covered and therefore completely black are fairly good. On the low-DPI screens, however, the situation is different. The pixels are too large for most of the details of a glyph and shades of gray are the norm rather than the exception.</p>
<p>This is relevant because all our screens have a second problem: they are not linear. 1&nbsp;+&nbsp;1 is not&nbsp;2. Twice the value does not result in twice the brightness. When a pixel is only 50% covered, the coverage map says 50% black, and this translates to a pixel value of 128 when you use 8&nbsp;bits per channel (0-255). However, this does not translate to 50% brightness for that pixel on our sRGB and gamma&nbsp;2.2 screens. Due to their non-linearity, they dwell longer in the darks and only a pixel value of about 186 results in 50% brightness – 128 ends up too dark on both bright and dark backgrounds. The net result is that dark text looks burnt-out, pixely and blotchy on bright background, bright text too frail on dark backgrounds, and colored text on colored background (for example, red on green) seems to have dark halos or &lsquo;dirt&rsquo; around it. The situation is especially ugly for diagonal stems like in &lsquo;w&rsquo; glyph shapes where the quality of FreeType's anti-aliasing depends on the correct display of grays. On high-DPI screens where smaller, fully black pixels reign supreme, this doesn't matter, but on our low-DPI screens with all the gray shades, it does. 0% and 100% brightness are the same things in linear and non-linear space, just all the shades in-between aren't.</p>
<p>The blending function for placing text over a background is</p>
<pre class="colored">
dst = alpha * src + (1 - alpha) * dst ,
</pre>
<p>which is known as the OVER operator.</p>
<p>To correctly composite an antialiased pixel of a glyph onto a surface,</p>
<p>1. take the foreground and background colors (e.g., in sRGB space) and apply gamma to get them in a linear space,</p>
<p>2. use OVER to blend the two linear colors using the glyph pixel as the alpha value (remember, the glyph bitmap is an alpha coverage bitmap), and</p>
<p>3. apply inverse gamma to the blended pixel and write it back to the image.</p>
<p>Internal testing at Adobe found that a target inverse gamma of&nbsp;1.8 for step&nbsp;3 gives good results across a wide range of displays with an sRGB gamma curve or a similar one.</p>
<p>This process can cost performance. There is an approximation that does not need to know about the background color; see <a href="https://bel.fi/alankila/lcd/">https://bel.fi/alankila/lcd/</a> and <a href="https://bel.fi/alankila/lcd/alpcor.html">https://bel.fi/alankila/lcd/alpcor.html</a> for details.</p>
<p><b>ATTENTION</b>: Linear blending is even more important when dealing with subpixel-rendered glyphs to prevent color-fringing! A subpixel-rendered glyph must first be filtered with a filter that gives equal weight to the three color primaries and does not exceed a sum of 0x100, see section &lsquo;<a href="ft2-lcd_filtering.html#lcd_filtering">LCD Filtering</a>&rsquo;. Then the only difference to gray linear blending is that subpixel-rendered linear blending is done 3&nbsp;times per pixel: red foreground subpixel to red background subpixel and so on for green and blue.</p>
<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="slot">slot</td><td class="desc">
<p>A handle to the glyph slot containing the image to convert.</p>
</td></tr>
</table>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="render_mode">render_mode</td><td class="desc">
<p>This is the render mode used to render the glyph image into a bitmap. See <a href="ft2-base_interface.html#FT_Render_Mode">FT_Render_Mode</a> for a list of possible values.</p>
</td></tr>
</table>
<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>
<h4>note</h4>
<p>To get meaningful results, font scaling values must be set with functions like <a href="ft2-base_interface.html#FT_Set_Char_Size">FT_Set_Char_Size</a> before calling FT_Render_Glyph.</p>
<hr>
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<div class="section">
<h3 id="FT_Render_Mode">FT_Render_Mode</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
<span class="keyword">typedef</span> <span class="keyword">enum</span> FT_Render_Mode_
{
<a href="ft2-base_interface.html#FT_RENDER_MODE_NORMAL">FT_RENDER_MODE_NORMAL</a> = 0,
<a href="ft2-base_interface.html#FT_RENDER_MODE_LIGHT">FT_RENDER_MODE_LIGHT</a>,
<a href="ft2-base_interface.html#FT_RENDER_MODE_MONO">FT_RENDER_MODE_MONO</a>,
<a href="ft2-base_interface.html#FT_RENDER_MODE_LCD">FT_RENDER_MODE_LCD</a>,
<a href="ft2-base_interface.html#FT_RENDER_MODE_LCD_V">FT_RENDER_MODE_LCD_V</a>,
FT_RENDER_MODE_MAX
} <b>FT_Render_Mode</b>;
/* these constants are deprecated; use the corresponding */
/* `<b>FT_Render_Mode</b>' values instead */
#define ft_render_mode_normal <a href="ft2-base_interface.html#FT_RENDER_MODE_NORMAL">FT_RENDER_MODE_NORMAL</a>
#define ft_render_mode_mono <a href="ft2-base_interface.html#FT_RENDER_MODE_MONO">FT_RENDER_MODE_MONO</a>
</pre>
<p>An enumeration type that lists the render modes supported by FreeType&nbsp;2. Each mode corresponds to a specific type of scanline conversion performed on the outline.</p>
<p>For bitmap fonts and embedded bitmaps the &lsquo;bitmap-&gt;pixel_mode&rsquo; field in the <a href="ft2-base_interface.html#FT_GlyphSlotRec">FT_GlyphSlotRec</a> structure gives the format of the returned bitmap.</p>
<p>All modes except <a href="ft2-base_interface.html#FT_Render_Mode">FT_RENDER_MODE_MONO</a> use 256 levels of opacity, indicating pixel coverage. Use linear alpha blending and gamma correction to correctly render non-monochrome glyph bitmaps onto a surface; see <a href="ft2-base_interface.html#FT_Render_Glyph">FT_Render_Glyph</a>.</p>
<h4>values</h4>
<table class="fields">
<tr><td class="val" id="FT_RENDER_MODE_NORMAL">FT_RENDER_MODE_NORMAL</td><td class="desc">
<p>This is the default render mode; it corresponds to 8-bit anti-aliased bitmaps.</p>
</td></tr>
<tr><td class="val" id="FT_RENDER_MODE_LIGHT">FT_RENDER_MODE_LIGHT</td><td class="desc">
<p>This is equivalent to <a href="ft2-base_interface.html#FT_Render_Mode">FT_RENDER_MODE_NORMAL</a>. It is only defined as a separate value because render modes are also used indirectly to define hinting algorithm selectors. See <a href="ft2-base_interface.html#FT_LOAD_TARGET_XXX">FT_LOAD_TARGET_XXX</a> for details.</p>
</td></tr>
<tr><td class="val" id="FT_RENDER_MODE_MONO">FT_RENDER_MODE_MONO</td><td class="desc">
<p>This mode corresponds to 1-bit bitmaps (with 2&nbsp;levels of opacity).</p>
</td></tr>
<tr><td class="val" id="FT_RENDER_MODE_LCD">FT_RENDER_MODE_LCD</td><td class="desc">
<p>This mode corresponds to horizontal RGB and BGR sub-pixel displays like LCD screens. It produces 8-bit bitmaps that are 3&nbsp;times the width of the original glyph outline in pixels, and which use the <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_LCD</a> mode.</p>
</td></tr>
<tr><td class="val" id="FT_RENDER_MODE_LCD_V">FT_RENDER_MODE_LCD_V</td><td class="desc">
<p>This mode corresponds to vertical RGB and BGR sub-pixel displays (like PDA screens, rotated LCD displays, etc.). It produces 8-bit bitmaps that are 3&nbsp;times the height of the original glyph outline in pixels and use the <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_LCD_V</a> mode.</p>
</td></tr>
</table>
<h4>note</h4>
<p>The LCD-optimized glyph bitmaps produced by FT_Render_Glyph can be filtered to reduce color-fringes by using <a href="ft2-lcd_filtering.html#FT_Library_SetLcdFilter">FT_Library_SetLcdFilter</a> (not active in the default builds). It is up to the caller to either call <a href="ft2-lcd_filtering.html#FT_Library_SetLcdFilter">FT_Library_SetLcdFilter</a> (if available) or do the filtering itself.</p>
<p>The selected render mode only affects vector glyphs of a font. Embedded bitmaps often have a different pixel mode like <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_MONO</a>. You can use <a href="ft2-bitmap_handling.html#FT_Bitmap_Convert">FT_Bitmap_Convert</a> to transform them into 8-bit pixmaps.</p>
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
<div class="section">
<h3 id="FT_Get_Kerning">FT_Get_Kerning</h3>
<p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
<pre>
FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
<b>FT_Get_Kerning</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> left_glyph,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> right_glyph,
<a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> kern_mode,
<a href="ft2-basic_types.html#FT_Vector">FT_Vector</a> *akerning );
</pre>
<p>Return the kerning vector between two glyphs of a same face.</p>
<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to a source face object.</p>
</td></tr>
<tr><td class="val" id="left_glyph">left_glyph</td><td class="desc">
<p>The index of the left glyph in the kern pair.</p>
</td></tr>
<tr><td class="val" id="right_glyph">right_glyph</td><td class="desc">
<p>The index of the right glyph in the kern pair.</p>
</td></tr>
<tr><td class="val" id="kern_mode">kern_mode</td><td class="desc">
<p>See <a href="ft2-base_interface.html#FT_Kerning_Mode">FT_Kerning_Mode</a> for more information. Determines the scale and dimension of the returned kerning vector.</p>
</td></tr>
</table>
<h4>output</h4>
<table class="fields">
<tr><td class="val" id="akerning">akerning</td><td class="desc">