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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-2.9.1 API Reference</h1>

<h1 id="gx_validation">TrueTypeGX/AAT Validation</h1>
<h2>Synopsis</h2>
<table class="synopsis">
<tr><td><a href="#FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</a></td><td><a href="#FT_ClassicKern_Validate">FT_ClassicKern_Validate</a></td><td><a href="#FT_VALIDATE_GX_LENGTH">FT_VALIDATE_GX_LENGTH</a></td></tr>
<tr><td><a href="#FT_TrueTypeGX_Free">FT_TrueTypeGX_Free</a></td><td><a href="#FT_ClassicKern_Free">FT_ClassicKern_Free</a></td><td><a href="#FT_VALIDATE_GXXXX">FT_VALIDATE_GXXXX</a></td></tr>
<tr><td>&nbsp;</td><td>&nbsp;</td><td><a href="#FT_VALIDATE_CKERNXXX">FT_VALIDATE_CKERNXXX</a></td></tr>
</table>

<p>This section contains the declaration of functions to validate some TrueTypeGX tables (feat, mort, morx, bsln, just, kern, opbd, trak, prop, lcar).</p>

<div class="section">
<h3 id="FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_TrueTypeGX_Validate</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a>   face,
                          <a href="ft2-basic_types.html#FT_UInt">FT_UInt</a>   validation_flags,
                          <a href="ft2-basic_types.html#FT_Bytes">FT_Bytes</a>  tables[<a href="ft2-gx_validation.html#FT_VALIDATE_GX_LENGTH">FT_VALIDATE_GX_LENGTH</a>],
                          <a href="ft2-basic_types.html#FT_UInt">FT_UInt</a>   table_length );
</pre>

<p>Validate various TrueTypeGX tables to assure that all offsets and indices are valid. The idea is that a higher-level library that actually does the text layout can access those tables without error checking (which can be quite time consuming).</p>

<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the input face.</p>
</td></tr>
<tr><td class="val" id="validation_flags">validation_flags</td><td class="desc">
<p>A bit field that specifies the tables to be validated. See <a href="ft2-gx_validation.html#FT_VALIDATE_GXXXX">FT_VALIDATE_GXXXX</a> for possible values.</p>
</td></tr>
<tr><td class="val" id="table_length">table_length</td><td class="desc">
<p>The size of the &lsquo;tables&rsquo; array. Normally, <a href="ft2-gx_validation.html#FT_VALIDATE_GX_LENGTH">FT_VALIDATE_GX_LENGTH</a> should be passed.</p>
</td></tr>
</table>

<h4>output</h4>
<table class="fields">
<tr><td class="val" id="tables">tables</td><td class="desc">
<p>The array where all validated sfnt tables are stored. The array itself must be allocated by a client.</p>
</td></tr>
</table>

<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>

<h4>note</h4>
<p>This function only works with TrueTypeGX fonts, returning an error otherwise.</p>
<p>After use, the application should deallocate the buffers pointed to by each &lsquo;tables&rsquo; element, by calling <a href="ft2-gx_validation.html#FT_TrueTypeGX_Free">FT_TrueTypeGX_Free</a>. A NULL value indicates that the table either doesn't exist in the font, the application hasn't asked for validation, or the validator doesn't have the ability to validate the sfnt table.</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_TrueTypeGX_Free">FT_TrueTypeGX_Free</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
  FT_EXPORT( <span class="keyword">void</span> )
  <b>FT_TrueTypeGX_Free</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a>   face,
                      <a href="ft2-basic_types.html#FT_Bytes">FT_Bytes</a>  table );
</pre>

<p>Free the buffer allocated by TrueTypeGX validator.</p>

<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the input face.</p>
</td></tr>
<tr><td class="val" id="table">table</td><td class="desc">
<p>The pointer to the buffer allocated by <a href="ft2-gx_validation.html#FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</a>.</p>
</td></tr>
</table>

<h4>note</h4>
<p>This function must be used to free the buffer allocated by <a href="ft2-gx_validation.html#FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</a> only.</p>

<div class="section">
<h3 id="FT_ClassicKern_Validate">FT_ClassicKern_Validate</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_ClassicKern_Validate</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a>    face,
                           <a href="ft2-basic_types.html#FT_UInt">FT_UInt</a>    validation_flags,
                           <a href="ft2-basic_types.html#FT_Bytes">FT_Bytes</a>  *ckern_table );
</pre>

<p>Validate classic (16-bit format) kern table to assure that the offsets and indices are valid. The idea is that a higher-level library that actually does the text layout can access those tables without error checking (which can be quite time consuming).</p>
<p>The &lsquo;kern&rsquo; table validator in <a href="ft2-gx_validation.html#FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</a> deals with both the new 32-bit format and the classic 16-bit format, while FT_ClassicKern_Validate only supports the classic 16-bit format.</p>

<h4>output</h4>
<table class="fields">
<tr><td class="val" id="ckern_table">ckern_table</td><td class="desc">
<p>A pointer to the kern table.</p>
</td></tr>
</table>

<h4>return</h4>
<p>FreeType error code. 0&nbsp;means success.</p>

<h4>note</h4>
<p>After use, the application should deallocate the buffers pointed to by &lsquo;ckern_table&rsquo;, by calling <a href="ft2-gx_validation.html#FT_ClassicKern_Free">FT_ClassicKern_Free</a>. A NULL value indicates that the table doesn't exist in the font.</p>

<div class="section">
<h3 id="FT_ClassicKern_Free">FT_ClassicKern_Free</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
  FT_EXPORT( <span class="keyword">void</span> )
  <b>FT_ClassicKern_Free</b>( <a href="ft2-base_interface.html#FT_Face">FT_Face</a>   face,
                       <a href="ft2-basic_types.html#FT_Bytes">FT_Bytes</a>  table );
</pre>

<p>Free the buffer allocated by classic Kern validator.</p>

<h4>input</h4>
<table class="fields">
<tr><td class="val" id="face">face</td><td class="desc">
<p>A handle to the input face.</p>
</td></tr>
<tr><td class="val" id="table">table</td><td class="desc">
<p>The pointer to the buffer that is allocated by <a href="ft2-gx_validation.html#FT_ClassicKern_Validate">FT_ClassicKern_Validate</a>.</p>
</td></tr>
</table>

<h4>note</h4>
<p>This function must be used to free the buffer allocated by <a href="ft2-gx_validation.html#FT_ClassicKern_Validate">FT_ClassicKern_Validate</a> only.</p>

<div class="section">
<h3 id="FT_VALIDATE_GX_LENGTH">FT_VALIDATE_GX_LENGTH</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
#define <b>FT_VALIDATE_GX_LENGTH</b>  ( FT_VALIDATE_GX_LAST_INDEX + 1 )
</pre>

<p>The number of tables checked in this module. Use it as a parameter for the &lsquo;table-length&rsquo; argument of function <a href="ft2-gx_validation.html#FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</a>.</p>

<div class="section">
<h3 id="FT_VALIDATE_GXXXX">FT_VALIDATE_GXXXX</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
#define <a href="ft2-gx_validation.html#FT_VALIDATE_feat">FT_VALIDATE_feat</a>  FT_VALIDATE_GX_BITFIELD( feat )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_mort">FT_VALIDATE_mort</a>  FT_VALIDATE_GX_BITFIELD( mort )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_morx">FT_VALIDATE_morx</a>  FT_VALIDATE_GX_BITFIELD( morx )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_bsln">FT_VALIDATE_bsln</a>  FT_VALIDATE_GX_BITFIELD( bsln )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_just">FT_VALIDATE_just</a>  FT_VALIDATE_GX_BITFIELD( just )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_kern">FT_VALIDATE_kern</a>  FT_VALIDATE_GX_BITFIELD( kern )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_opbd">FT_VALIDATE_opbd</a>  FT_VALIDATE_GX_BITFIELD( opbd )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_trak">FT_VALIDATE_trak</a>  FT_VALIDATE_GX_BITFIELD( trak )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_prop">FT_VALIDATE_prop</a>  FT_VALIDATE_GX_BITFIELD( prop )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_lcar">FT_VALIDATE_lcar</a>  FT_VALIDATE_GX_BITFIELD( lcar )

#define <a href="ft2-gx_validation.html#FT_VALIDATE_GX">FT_VALIDATE_GX</a>  ( <a href="ft2-gx_validation.html#FT_VALIDATE_feat">FT_VALIDATE_feat</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_mort">FT_VALIDATE_mort</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_morx">FT_VALIDATE_morx</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_bsln">FT_VALIDATE_bsln</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_just">FT_VALIDATE_just</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_kern">FT_VALIDATE_kern</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_opbd">FT_VALIDATE_opbd</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_trak">FT_VALIDATE_trak</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_prop">FT_VALIDATE_prop</a> | \
                          <a href="ft2-gx_validation.html#FT_VALIDATE_lcar">FT_VALIDATE_lcar</a> )
</pre>

<p>A list of bit-field constants used with <a href="ft2-gx_validation.html#FT_TrueTypeGX_Validate">FT_TrueTypeGX_Validate</a> to indicate which TrueTypeGX/AAT Type tables should be validated.</p>

<h4>values</h4>
<table class="fields">
<tr><td class="val" id="FT_VALIDATE_feat">FT_VALIDATE_feat</td><td class="desc">
<p>Validate &lsquo;feat&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_mort">FT_VALIDATE_mort</td><td class="desc">
<p>Validate &lsquo;mort&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_morx">FT_VALIDATE_morx</td><td class="desc">
<p>Validate &lsquo;morx&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_bsln">FT_VALIDATE_bsln</td><td class="desc">
<p>Validate &lsquo;bsln&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_just">FT_VALIDATE_just</td><td class="desc">
<p>Validate &lsquo;just&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_kern">FT_VALIDATE_kern</td><td class="desc">
<p>Validate &lsquo;kern&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_opbd">FT_VALIDATE_opbd</td><td class="desc">
<p>Validate &lsquo;opbd&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_trak">FT_VALIDATE_trak</td><td class="desc">
<p>Validate &lsquo;trak&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_prop">FT_VALIDATE_prop</td><td class="desc">
<p>Validate &lsquo;prop&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_lcar">FT_VALIDATE_lcar</td><td class="desc">
<p>Validate &lsquo;lcar&rsquo; table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_GX">FT_VALIDATE_GX</td><td class="desc">
<p>Validate all TrueTypeGX tables (feat, mort, morx, bsln, just, kern, opbd, trak, prop and lcar).</p>
</td></tr>
</table>

<div class="section">
<h3 id="FT_VALIDATE_CKERNXXX">FT_VALIDATE_CKERNXXX</h3>
<p>Defined in FT_GX_VALIDATE_H (freetype/ftgxval.h).</p>
<pre>
#define <a href="ft2-gx_validation.html#FT_VALIDATE_MS">FT_VALIDATE_MS</a>     ( FT_VALIDATE_GX_START &lt;&lt; 0 )
#define <a href="ft2-gx_validation.html#FT_VALIDATE_APPLE">FT_VALIDATE_APPLE</a>  ( FT_VALIDATE_GX_START &lt;&lt; 1 )

#define <a href="ft2-gx_validation.html#FT_VALIDATE_CKERN">FT_VALIDATE_CKERN</a>  ( <a href="ft2-gx_validation.html#FT_VALIDATE_MS">FT_VALIDATE_MS</a> | <a href="ft2-gx_validation.html#FT_VALIDATE_APPLE">FT_VALIDATE_APPLE</a> )
</pre>

<p>A list of bit-field constants used with <a href="ft2-gx_validation.html#FT_ClassicKern_Validate">FT_ClassicKern_Validate</a> to indicate the classic kern dialect or dialects. If the selected type doesn't fit, <a href="ft2-gx_validation.html#FT_ClassicKern_Validate">FT_ClassicKern_Validate</a> regards the table as invalid.</p>

<h4>values</h4>
<table class="fields">
<tr><td class="val" id="FT_VALIDATE_MS">FT_VALIDATE_MS</td><td class="desc">
<p>Handle the &lsquo;kern&rsquo; table as a classic Microsoft kern table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_APPLE">FT_VALIDATE_APPLE</td><td class="desc">
<p>Handle the &lsquo;kern&rsquo; table as a classic Apple kern table.</p>
</td></tr>
<tr><td class="val" id="FT_VALIDATE_CKERN">FT_VALIDATE_CKERN</td><td class="desc">
<p>Handle the &lsquo;kern&rsquo; as either classic Apple or Microsoft kern table.</p>
</td></tr>
</table>

</body>
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MR SKB