From e3fa24f095381f36fdc5fa17494ec16b5cd18fe8 Mon Sep 17 00:00:00 2001
From: Han-Wen Nienhuys <hanwen@xs4all.nl>
Date: Mon, 1 Jan 2007 16:54:19 +0100
Subject: [PATCH] Fix #122.

Add Stem::is_normal_stem(), which disregards stemlet-length.  Use it
for concaveness/slope calculations.
---
 input/regression/beam-slope-stemlet.ly | 22 ++++++++++++++++++++++
 lily/beam-concave.cc                   |  6 +++---
 lily/beam.cc                           |  7 ++++---
 lily/include/stem.hh                   |  1 +
 lily/stem.cc                           |  8 ++++++++
 5 files changed, 38 insertions(+), 6 deletions(-)
 create mode 100644 input/regression/beam-slope-stemlet.ly

diff --git a/input/regression/beam-slope-stemlet.ly b/input/regression/beam-slope-stemlet.ly
new file mode 100644
index 0000000000..a0657e81c4
--- /dev/null
+++ b/input/regression/beam-slope-stemlet.ly
@@ -0,0 +1,22 @@
+
+\header {
+
+  texidoc = "For slope calculations, stemlets are treated
+as invisible stems."
+
+}
+
+\version "2.10.7"
+
+\layout {
+  ragged-right = ##t
+  indent = #0
+}
+
+\relative c' {
+  \times 2/3 {r8[ c' g']}
+  \override Stem #'stemlet-length = #0.5
+  \times 2/3 {r8[ c, g']}
+}
+
+
diff --git a/lily/beam-concave.cc b/lily/beam-concave.cc
index ee351d0a26..a37005c17c 100644
--- a/lily/beam-concave.cc
+++ b/lily/beam-concave.cc
@@ -96,13 +96,13 @@ Beam::calc_concaveness (SCM smob)
   Direction beam_dir = CENTER;
   for (vsize i = stems.size (); i--;)
     {
-      if (Stem::is_invisible (stems[i]))
-	stems.erase (stems.begin () + i);
-      else
+      if (Stem::is_normal_stem (stems[i]))
 	{
 	  if (Direction dir = get_grob_direction (stems[i]))
 	    beam_dir = dir;
 	}
+      else
+	stems.erase (stems.begin () + i);
     }
 
   if (stems.size () <= 2)
diff --git a/lily/beam.cc b/lily/beam.cc
index 58fd432493..a2e7a3cb92 100644
--- a/lily/beam.cc
+++ b/lily/beam.cc
@@ -894,8 +894,9 @@ Beam::calc_least_squares_positions (SCM smob, SCM posns)
       for (vsize i = 0; i < stems.size (); i++)
 	{
 	  Grob *s = stems[i];
-	  if (Stem::is_invisible (s))
+	  if (!Stem::is_normal_stem (s))
 	    continue;
+
 	  ideals.push_back (Offset (x_posns[i],
 			       Stem::get_stem_info (s).ideal_y_
 			       + s->relative_coordinate (commony, Y_AXIS)
@@ -1287,7 +1288,7 @@ Beam::first_visible_stem (Grob *me)
 
   for (vsize i = 0; i < stems.size (); i++)
     {
-      if (!Stem::is_invisible (stems[i]))
+      if (Stem::is_normal_stem (stems[i]))
 	return stems[i];
     }
   return 0;
@@ -1300,7 +1301,7 @@ Beam::last_visible_stem (Grob *me)
 
   for (vsize i = stems.size (); i--;)
     {
-      if (!Stem::is_invisible (stems[i]))
+      if (Stem::is_normal_stem (stems[i]))
 	return stems[i];
     }
   return 0;
diff --git a/lily/include/stem.hh b/lily/include/stem.hh
index 8808d16665..b3663b6eee 100644
--- a/lily/include/stem.hh
+++ b/lily/include/stem.hh
@@ -33,6 +33,7 @@ public:
   static Real thickness (Grob *);
   static int head_count (Grob *);
   static bool is_invisible (Grob *);
+  static bool is_normal_stem (Grob *);
   static Interval head_positions (Grob *);
   static Real stem_end_position (Grob *);
   static Stencil flag (Grob *);
diff --git a/lily/stem.cc b/lily/stem.cc
index d333690491..6757582869 100644
--- a/lily/stem.cc
+++ b/lily/stem.cc
@@ -222,6 +222,14 @@ Stem::is_invisible (Grob *me)
 	   && scm_to_int (me->get_property ("duration-log")) >= 1);
 }
 
+
+bool
+Stem::is_normal_stem (Grob *me)
+{
+  return head_count (me) && scm_to_int (me->get_property ("duration-log")) >= 1;
+}
+
+
 MAKE_SCHEME_CALLBACK (Stem, pure_height, 3)
 SCM
 Stem::pure_height (SCM smob, SCM start, SCM end)
-- 
2.39.5