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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="bitmap_handling">Bitmap Handling</h1>
<h2>Synopsis</h2>
<table class="synopsis">
<tr><td><a href="#FT_Bitmap_Init">FT_Bitmap_Init</a></td><td><a href="#FT_Bitmap_Embolden">FT_Bitmap_Embolden</a></td><td><a href="#FT_GlyphSlot_Own_Bitmap">FT_GlyphSlot_Own_Bitmap</a></td></tr>
<tr><td><a href="#FT_Bitmap_Copy">FT_Bitmap_Copy</a></td><td><a href="#FT_Bitmap_Convert">FT_Bitmap_Convert</a></td><td><a href="#FT_Bitmap_Done">FT_Bitmap_Done</a></td></tr>
</table>

<p>This section contains functions for handling <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a> objects. Note that none of the functions changes the bitmap's &lsquo;flow&rsquo; (as indicated by the sign of the &lsquo;pitch&rsquo; field in &lsquo;FT_Bitmap&rsquo;).</p>

<div class="section">
<h3 id="FT_Bitmap_Init">FT_Bitmap_Init</h3>
<p>Defined in FT_BITMAP_H (freetype/ftbitmap.h).</p>
<pre>
  FT_EXPORT( <span class="keyword">void</span> )
  <b>FT_Bitmap_Init</b>( <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a>  *abitmap );

/* deprecated */
  FT_EXPORT( <span class="keyword">void</span> )
  FT_Bitmap_New( <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a>  *abitmap );
</pre>

<p>Initialize a pointer to an <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a> structure.</p>

<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="abitmap">abitmap</td><td class="desc">
<p>A pointer to the bitmap structure.</p>
</td></tr>
</table>

<h4>note</h4>
<p>A deprecated name for the same function is &lsquo;FT_Bitmap_New&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_Bitmap_Copy">FT_Bitmap_Copy</h3>
<p>Defined in FT_BITMAP_H (freetype/ftbitmap.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_Bitmap_Copy</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_Bitmap">FT_Bitmap</a>  *source,
                  <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a>        *target );
</pre>

<p>Copy a bitmap into another one.</p>

<h4>output</h4>
<table class="fields">
<tr><td class="val" id="target">target</td><td class="desc">
<p>A handle to the target bitmap.</p>
</td></tr>
</table>

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

<div class="section">
<h3 id="FT_Bitmap_Embolden">FT_Bitmap_Embolden</h3>
<p>Defined in FT_BITMAP_H (freetype/ftbitmap.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_Bitmap_Embolden</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a>  library,
                      <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a>*  bitmap,
                      <a href="ft2-basic_types.html#FT_Pos">FT_Pos</a>      xStrength,
                      <a href="ft2-basic_types.html#FT_Pos">FT_Pos</a>      yStrength );
</pre>

<p>Embolden a bitmap. The new bitmap will be about &lsquo;xStrength&rsquo; pixels wider and &lsquo;yStrength&rsquo; pixels higher. The left and bottom borders are kept unchanged.</p>

<h4>input</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to a library object.</p>
</td></tr>
<tr><td class="val" id="xStrength">xStrength</td><td class="desc">
<p>How strong the glyph is emboldened horizontally. Expressed in 26.6 pixel format.</p>
</td></tr>
<tr><td class="val" id="yStrength">yStrength</td><td class="desc">
<p>How strong the glyph is emboldened vertically. Expressed in 26.6 pixel format.</p>
</td></tr>
</table>

<h4>inout</h4>
<table class="fields">
<tr><td class="val" id="bitmap">bitmap</td><td class="desc">
<p>A handle to the target bitmap.</p>
</td></tr>
</table>

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

<h4>note</h4>
<p>The current implementation restricts &lsquo;xStrength&rsquo; to be less than or equal to&nbsp;8 if bitmap is of pixel_mode <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_MONO</a>.</p>
<p>If you want to embolden the bitmap owned by a <a href="ft2-base_interface.html#FT_GlyphSlotRec">FT_GlyphSlotRec</a>, you should call <a href="ft2-bitmap_handling.html#FT_GlyphSlot_Own_Bitmap">FT_GlyphSlot_Own_Bitmap</a> on the slot first.</p>
<p>Bitmaps in <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_GRAY2</a> and <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_GRAY</a>@ format are converted to <a href="ft2-basic_types.html#FT_Pixel_Mode">FT_PIXEL_MODE_GRAY</a> format (i.e., 8bpp).</p>

<div class="section">
<h3 id="FT_Bitmap_Convert">FT_Bitmap_Convert</h3>
<p>Defined in FT_BITMAP_H (freetype/ftbitmap.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_Bitmap_Convert</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_Bitmap">FT_Bitmap</a>  *source,
                     <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a>        *target,
                     <a href="ft2-basic_types.html#FT_Int">FT_Int</a>            alignment );
</pre>

<p>Convert a bitmap object with depth 1bpp, 2bpp, 4bpp, 8bpp or 32bpp to a bitmap object with depth 8bpp, making the number of used bytes line (a.k.a. the &lsquo;pitch&rsquo;) a multiple of &lsquo;alignment&rsquo;.</p>

<h4>input</h4>
<table class="fields">
<tr><td class="val" id="library">library</td><td class="desc">
<p>A handle to a library object.</p>
</td></tr>
<tr><td class="val" id="source">source</td><td class="desc">
<p>The source bitmap.</p>
</td></tr>
<tr><td class="val" id="alignment">alignment</td><td class="desc">
<p>The pitch of the bitmap is a multiple of this parameter. Common values are 1, 2, or 4.</p>
</td></tr>
</table>

<h4>output</h4>
<table class="fields">
<tr><td class="val" id="target">target</td><td class="desc">
<p>The target bitmap.</p>
</td></tr>
</table>

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

<h4>note</h4>
<p>It is possible to call <a href="ft2-bitmap_handling.html#FT_Bitmap_Convert">FT_Bitmap_Convert</a> multiple times without calling <a href="ft2-bitmap_handling.html#FT_Bitmap_Done">FT_Bitmap_Done</a> (the memory is simply reallocated).</p>
<p>Use <a href="ft2-bitmap_handling.html#FT_Bitmap_Done">FT_Bitmap_Done</a> to finally remove the bitmap object.</p>
<p>The &lsquo;library&rsquo; argument is taken to have access to FreeType's memory handling functions.</p>

<div class="section">
<h3 id="FT_GlyphSlot_Own_Bitmap">FT_GlyphSlot_Own_Bitmap</h3>
<p>Defined in FT_BITMAP_H (freetype/ftbitmap.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_GlyphSlot_Own_Bitmap</b>( <a href="ft2-base_interface.html#FT_GlyphSlot">FT_GlyphSlot</a>  slot );
</pre>

<p>Make sure that a glyph slot owns &lsquo;slot-&gt;bitmap&rsquo;.</p>

<h4>input</h4>
<table class="fields">
<tr><td class="val" id="slot">slot</td><td class="desc">
<p>The glyph slot.</p>
</td></tr>
</table>

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

<h4>note</h4>
<p>This function is to be used in combination with <a href="ft2-bitmap_handling.html#FT_Bitmap_Embolden">FT_Bitmap_Embolden</a>.</p>

<div class="section">
<h3 id="FT_Bitmap_Done">FT_Bitmap_Done</h3>
<p>Defined in FT_BITMAP_H (freetype/ftbitmap.h).</p>
<pre>
  FT_EXPORT( <a href="ft2-basic_types.html#FT_Error">FT_Error</a> )
  <b>FT_Bitmap_Done</b>( <a href="ft2-base_interface.html#FT_Library">FT_Library</a>  library,
                  <a href="ft2-basic_types.html#FT_Bitmap">FT_Bitmap</a>  *bitmap );
</pre>

<p>Destroy a bitmap object initialized with <a href="ft2-bitmap_handling.html#FT_Bitmap_Init">FT_Bitmap_Init</a>.</p>

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

<h4>note</h4>
<p>The &lsquo;library&rsquo; argument is taken to have access to FreeType's memory handling functions.</p>

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MR SKB