p>
<p>This value is invalid in many fonts, as it is usually set by the font designer, and often reflects only a portion of the glyphs found in the font (maybe ASCII).</p>
<p>You should use the &lsquo;sTypoDescender&rsquo; field of the OS/2 table instead if you want the correct one.</p>
</td></tr>
<tr valign=top><td><b>Line_Gap</b></td><td>
<p>The font's line gap, i.e., the distance to add to the ascender and descender to get the BTB, i.e., the baseline-to-baseline distance for the font.</p>
</td></tr>
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