Restore announce files for 2.0 - 2.12.

[lilypond.git] / lily / item.cc

diff --git a/lily/item.cc b/lily/item.cc
index 6ea5643a5445e7d791a119479e73d54a5fe7aead..0c3169a7766f31860ef77b978ad7829c017f58b1 100644 (file)
--- a/lily/item.cc
+++ b/lily/item.cc
@@ -241,6 +241,10 @@ Item::pure_height (Grob *g, int start, int end)
 {
   if (cached_pure_height_valid_)
     return cached_pure_height_ + pure_relative_y_coordinate (g, start, end);
+  /* Note: cached_pure_height_ does not notice if start changes, implicitly
+     assuming that Items' pure_heights do not depend on 'start' or 'end'.
+     Accidental_interface::pure_height(), however, does depend on 'start'.
+  */
 
   cache_pure_height (Grob::pure_height (this, start, end));
   return cached_pure_height_ + pure_relative_y_coordinate (g, start, end);