title: Add grob to a base plot in R
body: <p>I would like to add a multiline text that I have constructed using <code>splitTextGorb</code> from the package <code>RGraphics</code> to a base plot. I tried the following but this doesn't work (i.e the text doesn't show on the plot)</p>
  
  <pre><code>layout(matrix(c(1,2), nrow=2, byrow=TRUE), heights = c(1,1.5))    
  plot(...)
  grob = splitTextGrob("This is my text")
  plot.new()
  vp.BottomRight &lt;- viewport(height=unit(.5, "npc"), width=unit(0.5, "npc"), 
                         just=c("left","top"), 
                         y=0.5, x=0.5)
  print(grob, vp = vp.BottonRight)
  </code></pre>
  
  <p>I know that <code>mtext</code> is an option to add text to a base plot, but I would like to use <code>splitTextGrob</code> specifically because it offers some flexibility that <code>mtext</code> or <code>grid.text()</code> doesn't.</p>
  
  <p>Any help would be appreciated. Thank you!</p>