title: Attach a picture to the coordinate axis of the facet of the picture
body: <p>I want to make the name of manufacturer (in the ggplot picture is text) to pictures, attach some pictures to the coordinate axis of the facet.</p>
  <p><strong>My code:</strong></p>
  <pre><code> ggplot(mpg, aes(drv, model)) +
       geom_point() + 
       facet_grid(manufacturer ~ ., scales = &quot;free&quot;, space = &quot;free&quot;)
  </code></pre>
  <p>I racked my brains for this, but I still haven’t solved it.</p>