o locate a position in a string in code (using
the <a href="dart-ui/TextPosition/offset.html">offset</a> property), and it can also be used to locate the same position
visually in a rendered string of text (using <a href="dart-ui/TextPosition/offset.html">offset</a> and, when needed to
resolve ambiguity, <a href="dart-ui/TextPosition/affinity.html">affinity</a>).</p>
<p>The location of an offset in a rendered string is ambiguous in two cases.
One happens when rendered text is forced to wrap. In this case, t