1 files changed, 9 insertions, 3 deletions
diff --git a/js/undo.js b/js/undo.js
index 436422f..44b137a 100644
--- a/js/undo.js
+++ b/js/undo.js
@@ -33,6 +33,12 @@ var update_dom = function(){
   update_dom_visibility('redo')
 }
 
+// state is an undo or redo state that might contain these props
+// {lexs: {'0,0': LexState, ...},
+//  focus: {x:, y: },
+//  size: {w:, h: },
+//  rects: [{x:, y:, w:, h:, lexs: [LexState, ...]}, ...]
+// }
 var new_state = function(){
   var state = {lexs:{}};
   save_focus(canvas.focus_x, canvas.focus_y, state)
@@ -98,20 +104,20 @@ var save_resize = function(w, h, old_w, old_h, state){
   state = state || current_undo
   save_size(old_w, old_h, state)
   if (old_w > w){
-    // .----.
+    // .---XX
     // |   XX
     // |___XX
     save_rect(w, 0, old_w - w, old_h, state)
     if (old_h > h){
       // .----.
       // |    |
-      // |XXX_|
+      // XXXX_|
       save_rect(0, h, w, old_h - h, state)
     }
   } else if (old_h > h){
     // .----.
     // |    |
-    // |XXXX|
+    // XXXXXX
     save_rect(0, h, old_w, old_h - h, state)
   }
 }