title: density shadow around the data with ggplot2 (R)
body: <p>I am trying to have 2 "shadows" on the background of the below plot. These shadows should represent the density of the orange and blue points separately. Does it make sense?</p>
  
  <p>Here is the ggplot to improve:
  <img src="https://i.stack.imgur.com/o0gay.png" alt="enter image description here"></p>
  
  <p>Here is the code and the data (matrix <code>df</code>) I used to create this plot:</p>
  
  <pre><code>                         PC1           PC2 aa
  A_akallopisos    0.043272525  0.0151023307  2
  A_akindynos     -0.020707141 -0.0158198405  1
  A_allardi       -0.020277664 -0.0221016281  2
  A_barberi       -0.023165596  0.0389906701  2
  A_bicinctus     -0.025354572 -0.0059122384  2
  A_chrysogaster   0.012608835 -0.0339330213  2
  A_chrysopterus  -0.022402365 -0.0092476009  1
  A_clarkii       -0.014474658 -0.0127024469  1
  A_ephippium     -0.016859412  0.0320034231  2
  A_frenatus      -0.024190876  0.0238499714  2
  A_latezonatus   -0.010718845 -0.0289904165  1
  A_latifasciatus -0.005645811 -0.0183202248  2
  A_mccullochi    -0.031664307 -0.0096059126  2
  A_melanopus     -0.026915545  0.0308399009  2
  A_nigripes       0.023420045  0.0293801537  2
  A_ocellaris      0.052042539  0.0126144250  2
  A_omanensis     -0.020387101  0.0010944998  2
  A_pacificus      0.042406273 -0.0260308092  2
  A_percula        0.034591721  0.0071153133  2
  A_perideraion    0.052830132  0.0064495142  2
  A_polymnus       0.030902254 -0.0005091421  2
  A_rubrocinctus  -0.033318659  0.0474995722  2
  A_sandaracinos   0.055839755  0.0093724082  2
  A_sebae          0.021767793 -0.0218640814  2
  A_tricinctus    -0.016230301 -0.0018526482  1
  P_biaculeatus   -0.014466403  0.0024864574  2
  
  
  
   ggplot(data=df,aes(x=PC1, y=PC2, color=factor(aa), label=rownames(df))) + ggtitle(paste('Site n° ',Sites_names[j],sep='')) +geom_smooth(se=F, method='lm')+ geom_point() + scale_color_manual(name='mutation', values = c("darkorange2","cornflowerblue"), labels = c("A","S")) + geom_text(hjust=0.5, vjust=-1 ,size=3) + xlim(-0.05,0.07)
  </code></pre>