title: Adjust geom_point size so large values are plotted, but do not appear larger in ggplot2?
body: <p>The issue I am having is that I would like the points above a certain threshold (=&lt;25) to not produce points larger than the set scale. These larger points still need to be displayed, and cannot be excluded:</p>
  
  <pre><code>d=data.frame(y=c(1,2,6,4,4,6,7,8),
               x=c(8,4,7,5,4,9,2,3),
               coverage=c(0,6,9,88,25,22,17,100),
               col=c(0,.25,.50,.76,.80,1.00,.11,.34)
               )
  ggplot() + 
    scale_size(range = c(0, 13),
               breaks = c(0, 5, 10, 20, 25),
               labels = c("0", "5", "10", "20", "25+"),
               guide = "legend"
    ) +
    geom_point(data = d, mapping = aes(x = x, y = y, color = col, size = coverage)) +
    labs(title = "geom_point")
  </code></pre>
  
  <p>In the above sample code I have two points which have a "coverage" larger than 25+ and are outside of the scale. I would like these points to appear the same size as the 25+ threshold.</p>
  
  <p><a href="https://i.stack.imgur.com/BNqz9.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BNqz9.jpg" alt="Example Plot output"></a></p>