X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fbreathing-sign.cc;h=e568e358e9ce14071e3970f56e64f188e0f6a3b8;hb=168396a9922e94135c1e2cd1624276e7390b1513;hp=a3d9637bef6d2d2e3685c8b23334b97b49804e13;hpb=4e2c5af7db8d46116c25ff7ebf00c39d76c109b3;p=lilypond.git

diff --git a/lily/breathing-sign.cc b/lily/breathing-sign.cc
index a3d9637bef..e568e358e9 100644
--- a/lily/breathing-sign.cc
+++ b/lily/breathing-sign.cc
@@ -76,18 +76,67 @@ Breathing_sign::divisio_maior (SCM smob)
   Real blotdiameter = me->layout ()->get_dimension (ly_symbol2scm ("blot-diameter"));
 
   /*
-   * Draw a vertical line that is vertically centered in the staff
-   * (just like a bar).  The height of this line should be a little
-   * more than half the size of the staff, such that the endings of
-   * the line are in the middle of a staff space.
-   */
-  int lines = Staff_symbol_referencer::line_count (me);
-  int height = lines / 2; // little more than half of staff size
-  if ((lines & 1) != (height & 1))
-    height++; // ensure endings are centered in staff space
+    Draw a vertical line that is roughly centered vertically in
+    the staff (just like a bar) with the following requirements:
+    1. length should be at least half the size of the staff
+    2. both ends should be in the middle of a staff space.
+
+    These two requirements contradict if the first or last space is
+    larger than half of the whole staff (e.g. the staff consists of
+    two lines only); in such cases the first prescription wins.
+  */
+  Interval ydim (0.0, 0.0);
+  if (Grob *staff = Staff_symbol_referencer::get_staff_symbol (me))
+    {
+      std::vector<Real> line_pos = Staff_symbol::line_positions (staff);
+      if (!line_pos.empty ())
+        {
+          std::sort (line_pos.begin (), line_pos.end ());
+          ydim[DOWN] = line_pos.front ();
+          ydim[UP] = line_pos.back ();
+          if (Real const height = ydim.length ())
+            {
+              ydim.widen (-0.25 * height);
+
+              /*
+                ydim has now the required height; to satisfy req. 2
+                find the staff spaces containing current endpoints.
+
+                standard algorithms are suitable to find the upper
+                line of these spaces; we must choose between
+                upper_bound and lower_bound considering that if
+                there's a line exactly at quarter of the staff (the
+                lower end) then we need the space below it, while if
+                there's a line exactly at three quarters of the staff
+                (upper end) then we need the space above it.
+
+                if the middle of the space found is not low/high
+                enough, take the next space (if there are no more
+                spaces, ydim won't be enlarged further).
+              */
+              std::vector<Real>::const_iterator it
+                = std::lower_bound (line_pos.begin (), line_pos.end (),
+                                    ydim[DOWN]);
+              assert (line_pos.begin () < it);
+              double val = (it[-1] + it[0]) / 2;
+              if (ydim[DOWN] < val && line_pos.begin () < it + 1)
+                val = (it[-2] + it[-1]) / 2;
+              ydim.add_point (val);
+
+              it = std::upper_bound (line_pos.begin (), line_pos.end (),
+                                     ydim[UP]);
+              assert (it < line_pos.end ());
+              val = (it[-1] + it[0]) / 2;
+              if (val < ydim[UP] && it + 1 < line_pos.end ())
+                val = (it[0] + it[1]) / 2;
+              ydim.add_point (val);
+            }
+        }
+    }
+
+  ydim *= Staff_symbol_referencer::staff_space (me) / 2;
 
   Interval xdim (0, thickness);
-  Interval ydim (-0.5 * height, +0.5 * height);
   Box b (xdim, ydim);
   Stencil out = Lookup::round_filled_box (b, blotdiameter);
   return out.smobbed_copy ();
@@ -102,20 +151,15 @@ Breathing_sign::divisio_maxima (SCM smob)
 {
   Grob *me = unsmob_grob (smob);
   Real staff_space = Staff_symbol_referencer::staff_space (me);
-  Real staff_size;
   Real thickness = Staff_symbol_referencer::line_thickness (me);
   thickness *= robust_scm2double (me->get_property ("thickness"), 1.0);
 
-  if (Staff_symbol_referencer::get_staff_symbol (me))
-    staff_size = (Staff_symbol_referencer::line_count (me) - 1) * staff_space;
-  else
-    staff_size = 0.0;
-
   Real blotdiameter = me->layout ()->get_dimension (ly_symbol2scm ("blot-diameter"));
 
   // like a "|" type bar
   Interval xdim (0, thickness);
-  Interval ydim (-0.5 * staff_size, +0.5 * staff_size);
+  Interval ydim = Staff_symbol_referencer::staff_span (me);
+  ydim *= staff_space / 2;
   Box b (xdim, ydim);
   Stencil out = Lookup::round_filled_box (b, blotdiameter);
   return out.smobbed_copy ();
@@ -130,20 +174,15 @@ Breathing_sign::finalis (SCM smob)
 {
   Grob *me = unsmob_grob (smob);
   Real staff_space = Staff_symbol_referencer::staff_space (me);
-  Real staff_size;
   Real thickness = Staff_symbol_referencer::line_thickness (me);
   thickness *= robust_scm2double (me->get_property ("thickness"), 1.0);
 
-  if (Staff_symbol_referencer::get_staff_symbol (me))
-    staff_size = (Staff_symbol_referencer::line_count (me) - 1) * staff_space;
-  else
-    staff_size = 0.0;
-
   Real blotdiameter = me->layout ()->get_dimension (ly_symbol2scm ("blot-diameter"));
 
   // like a "||" type bar
   Interval xdim (0, thickness);
-  Interval ydim (-0.5 * staff_size, +0.5 * staff_size);
+  Interval ydim = Staff_symbol_referencer::staff_span (me);
+  ydim *= staff_space / 2;
   Box b (xdim, ydim);
   Stencil line1 = Lookup::round_filled_box (b, blotdiameter);
   Stencil line2 (line1);