title: Add jitter to box plot using markers in plotly
body: <p>I made a boxplot:</p>
  
  <pre><code>dat %&gt;%
    plot_ly(y = ~xval, color = ~get(col), type = "box", 
            boxpoints = "all", jitter = 0.7,
            pointpos = 0, marker = list(size = 3),
            source = shiny_source, key = shiny_key,
            hoverinfo = 'text', text = txt)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/L91m6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/L91m6.png" alt="enter image description here"></a></p>
  
  <p>but problem is that jittered points are not interactive and cannot be marked separately, so I came with an idea to add those points using <code>add_markers</code>:</p>
  
  <pre><code>dat %&gt;%
    plot_ly(y = ~xval, color = ~get(col), type = "box", 
            boxpoints = FALSE, jitter = 0.7,
            pointpos = 0, marker = list(size = 3),
            source = shiny_source, key = shiny_key,
            hoverinfo = 'col', text = txt
    ) %&gt;%
    add_markers(x = ~get(col), y = ~varval, size = I(6))
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/BcGri.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BcGri.png" alt="enter image description here"></a></p>
  
  <p>but now points are in straight line and I'd like to add some jitter (for example by using <code>beeswarm</code> package). But I don't know how to get coordinates of qualitative variable <code>IC0</code> on X axis. Any ideas?</p>