bject has a
transparent background.</p>
<p>The <code>opaqueBackground</code> property is intended mainly for use
with the <code>cacheAsBitmap</code> property, for rendering optimization.
For display objects in which the <code>cacheAsBitmap</code> property is
set to true, setting <code>opaqueBackground</code> can improve rendering
performance.</p>
<p>The opaque background region is <em>not</em> matched when calling the
<code>hitTestPoint()</code> method with the <code>shapeFlag</code>
parameter set to <code>