Issue 4274: Fix a cyclic dependency in Rest_collision (issue 193590043 by address@hidden)

[nine . fierce . ballads]

Reviewers: ,

Description:
Rest_collision::calc_positioning_done now uses the pure height of
rests because the height of certain rests depends on their position on
the staff, which Rest_collision is responsible for adjusting.

There are differences in regression test output that I can not yet
explain.  The differences do not appear when I run lilypond by itself,
so I'm expecting to have to dig up the exact command the regtests run.
I'm posting this review anyway in hopes that a reviewer will recognize
the problem.

Please review this at https://codereview.appspot.com/193590043/

Affected files (+5, -5 lines):
  M lily/rest-collision.cc


Index: lily/rest-collision.cc
diff --git a/lily/rest-collision.cc b/lily/rest-collision.cc
index  
7648f6d9a09825109e54f879442e3b3d1c2f2fca..c7c032eb399761f55aaa69181c06928f59747ad7  
100644
--- a/lily/rest-collision.cc
+++ b/lily/rest-collision.cc
@@ -171,8 +171,8 @@ Rest_collision::calc_positioning_done (SCM smob)
       common = common_refpoint_of_array (ordered_rests[UP], common,  
Y_AXIS);

       Real diff
-        = (ordered_rests[DOWN].back ()->extent (common, Y_AXIS)[UP]
-           - ordered_rests[UP].back ()->extent (common, Y_AXIS)[DOWN]) /  
staff_space;
+        = (ordered_rests[DOWN].back ()->pure_height (common, 0, 0)[UP]
+           - ordered_rests[UP].back ()->pure_height (common, 0, 0)[DOWN])  
/ staff_space;

       if (diff > 0)
         {
@@ -189,8 +189,8 @@ Rest_collision::calc_positioning_done (SCM smob)
         {
           for (vsize i = ordered_rests[d].size () - 1; i-- > 0;)
             {
-              Real last_y = ordered_rests[d][i + 1]->extent (common,  
Y_AXIS)[d];
-              Real y = ordered_rests[d][i]->extent (common, Y_AXIS)[-d];
+              Real last_y = ordered_rests[d][i + 1]->pure_height (common,  
0, 0)[d];
+              Real y = ordered_rests[d][i]->pure_height (common, 0, 0)[-d];

               Real diff = d * ((last_y - y) / staff_space);
               if (diff > 0)
@@ -221,7 +221,7 @@ Rest_collision::calc_positioning_done (SCM smob)
             continue;

           Grob *common = common_refpoint_of_array (notes, rcol, Y_AXIS);
-          Interval restdim = rest->extent (common, Y_AXIS);
+          Interval restdim = rest->pure_height (common, 0, 0);
           if (restdim.is_empty ())
             continue;