el="anchor" href="#adding-in-convex-hulls-to-iso-space-plots"></a>
</h2>
<p>It’s perfectly possible to add polygons and convex hulls to existing
iso-space plots. This does require a bit of hacking though, and is
assisted by use of the package <code>ggnewscale</code>. Starting for
example with the iso-space plot above:</p>
<div class="sourceCode" id="cb10"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">p</span> <span class="op">&lt;-</span> <span class="fu"><a href="ht