toolbox/Candidate_site.draw: draw amino acids

lib/toolbox/candidate_site.ml

@@ -89,14 +89,19 @@ let collapsed_tree ~f t =
   and branch (Branch b) = Tree.branch b.data (tree b.tip) in
   tree (tree_add_cond_at_leaves t)
 
-let ratio = 8.
+let ratio = 4.
 
 let draw_profile ~col xs =
   let open Biotk_croquis.Croquis in
   let n = Array.length xs in
   List.init n ~f:(fun i ->
       let x = float i /. ratio in
-      Picture.rect ~fill:col ~xmin:x ~xmax:(x +. 1. /. (ratio +. 1.)) ~ymin:0. ~ymax:xs.(i) ()
+      let xtext = (x +. x +. 1. /. (ratio +. 1.)) /. 2. in
+      let aa = Amino_acid.(to_char (of_int_exn i)) |> Char.to_string in
+      Picture.blend [
+        Picture.text ~x:xtext ~y:0. ~valign:`base ~halign:`middle ~size:0.2 aa ;
+        Picture.rect ~fill:col ~xmin:x ~xmax:(x +. 1. /. (ratio +. 1.)) ~ymin:0. ~ymax:xs.(i) () ;
+      ]
     )
   |> Picture.blend