 point on the timeline
between <code>a</code> and <code>b</code>. The interpolation can be extrapolated beyond 0.0 and
1.0, so negative values and values greater than 1.0 are valid (and can
easily be generated by curves such as <code>Curves.elasticInOut</code>).</p>
<p>Values for <code>t</code> are usually obtained from an <code>Animation&lt;double&gt;</code>, such as
an <code>AnimationController</code>.</p>
    </section>
    
    <section class="summary source-code" id="source">
      <h2><span>Implementa