Make the length of beamlets configurable.

diff --git a/lily/beam.cc b/lily/beam.cc
index b2f015148ae28bcd7ba675617911a2068564509a..250b055a658b55d484ca1d669b5bdb60cd55d343 100644 (file)
--- a/lily/beam.cc
+++ b/lily/beam.cc
@@ -424,24 +424,26 @@ Beam::get_beam_segments (Grob *me_grob, Grob **common)
          // are looking at that edge of the beam segment that is furthest from its
          // stem).
          Direction event_dir = LEFT;
+         Beam_stem_segment const& seg = segs[j];
          do
            {
+             Beam_stem_segment const& neighbor_seg = segs[j + event_dir];
              // TODO: make names clearer? --jneem
              // on_line_bound: whether the current segment is on the boundary of the WHOLE beam
              // on_beam_bound: whether the current segment is on the boundary of just that part
              //   of the beam with the current beam_rank
-             bool on_line_bound = (segs[j].dir_ == LEFT) ? segs[j].stem_index_ == 0
-               : segs[j].stem_index_ == stems.size() - 1;
+             bool on_line_bound = (seg.dir_ == LEFT) ? seg.stem_index_ == 0
+               : seg.stem_index_ == stems.size() - 1;
              bool on_beam_bound = (event_dir == LEFT) ? j == 0 :
                j == segs.size () - 1;
              bool inside_stem = (event_dir == LEFT)
-               ? segs[j].stem_index_ > 0
-               : segs[j].stem_index_ + 1 < stems.size () ;
+               ? seg.stem_index_ > 0
+               : seg.stem_index_ + 1 < stems.size () ;
                      
              bool event = on_beam_bound
-               || abs (segs[j].rank_ - segs[j+event_dir].rank_) > 1
-               || (abs (vertical_count) >= segs[j].max_connect_
-                   || abs (vertical_count) >= segs[j + event_dir].max_connect_);
+               || abs (seg.rank_ - neighbor_seg.rank_) > 1
+               || (abs (vertical_count) >= seg.max_connect_
+                   || abs (vertical_count) >= neighbor_seg.max_connect_);
              
              if (!event)
                // Then this edge of the current segment is irrelevent because it will
@@ -449,8 +451,8 @@ Beam::get_beam_segments (Grob *me_grob, Grob **common)
                continue;
 
              current.vertical_count_ = vertical_count;
-             current.horizontal_[event_dir] = segs[j].stem_x_;
-             if (segs[j].dir_ == event_dir)
+             current.horizontal_[event_dir] = seg.stem_x_;
+             if (seg.dir_ == event_dir)
                // then we are examining the edge of a beam segment that is furthest
                // from its stem.
                {
@@ -464,40 +466,40 @@ Beam::get_beam_segments (Grob *me_grob, Grob **common)
                    }
                  else
                    {
-                     Real notehead_width = 
-                       Stem::duration_log (segs[j].stem_) == 1
-                       ? 1.98
-                       : 1.32; // URG.
-
+                     Grob *stem = stems[seg.stem_index_];
+                     Drul_array<Real> beamlet_length =
+                       robust_scm2interval (stem->get_property ("beamlet-default-length"), Interval (1.0, 1.0));
+                     Drul_array<Real> max_proportion =
+                       robust_scm2interval (stem->get_property ("beamlet-max-length-proportion"), Interval (0.5, 0.5));
+                     Real length = beamlet_length[seg.dir_];
 
                      if (inside_stem)
                        {
-                         Grob *neighbor_stem = stems[segs[j].stem_index_ + event_dir];
-                         Real neighbor_stem_x
-                           = neighbor_stem->relative_coordinate (commonx, X_AXIS);
+                         Grob *neighbor_stem = stems[seg.stem_index_ + event_dir];
+                         Real neighbor_stem_x = neighbor_stem->relative_coordinate (commonx, X_AXIS);
 
-                         notehead_width = min (notehead_width,
-                                               fabs (neighbor_stem_x - segs[j].stem_x_)/2.5);
+                         length = min (length,
+                                       fabs (neighbor_stem_x - seg.stem_x_) * max_proportion[seg.dir_]);
                        }
-                     current.horizontal_[event_dir] += event_dir * notehead_width;
+                     current.horizontal_[event_dir] += event_dir * length;
                    }
                }
              else
                // we are examining the edge of a beam segment that is closest
                // (ie. touching, unless there is a gap) its stem.
                {
-                 current.horizontal_[event_dir] += event_dir * segs[j].width_/2;
-                 if (segs[j].gapped_)
+                 current.horizontal_[event_dir] += event_dir * seg.width_/2;
+                 if (seg.gapped_)
                    {
                      current.horizontal_[event_dir] -= event_dir * gap_length;
 
-                     if (Stem::is_invisible (segs[j].stem_))
+                     if (Stem::is_invisible (seg.stem_))
                        {
                          /*
                            Need to do this in case of whole notes. We don't want the
                            heads to collide with the beams.
                           */
-                         extract_grob_set (segs[j].stem_, "note-heads", heads);
+                         extract_grob_set (seg.stem_, "note-heads", heads);
 
                          for (vsize k = 0; k < heads.size (); k ++)
                            current.horizontal_[event_dir]

diff --git a/lily/stem.cc b/lily/stem.cc
index 1f8b21e85f51fec72fa86c818b24417dcde43298..0ec01fd1080c0c8a8c91cf014ce9b8db2f0cdf25 100644 (file)
--- a/lily/stem.cc
+++ b/lily/stem.cc
@@ -1052,6 +1052,8 @@ ADD_INTERFACE (Stem,
               "avoid-note-head "
               "beam "
               "beaming "
+              "beamlet-default-length "
+              "beamlet-max-length-proportion "
               "default-direction "
               "details "
               "direction "

diff --git a/scm/define-grob-properties.scm b/scm/define-grob-properties.scm
index b697af3b300136ab1487802c96fdb4e976a86dbd..9c12167d1aea26cb0d6dd5cb995bc9673f57f533 100644 (file)
--- a/scm/define-grob-properties.scm
+++ b/scm/define-grob-properties.scm
@@ -79,6 +79,14 @@ specifies which beams to make.  @code{0}@tie{}is the central beam,
 @code{1}@tie{}is the next beam toward the note, etc.  This
 information is used to determine how to connect the beaming patterns
 from stem to stem inside a beam.")
+     (beamlet-default-length ,pair? "A pair of numbers. The first number
+specifies the default length of a beamlet that sticks out of the left hand
+side of this stem; the second number specifies the default length of the
+beamlet to the right. The actual length of a beamlet is determined by
+taking either the default length or the length specified by
+@code{beamlet-max-length-proportion}, whichever is smaller.")
+     (beamlet-max-length-proportion ,pair? "The maximum length of a beamlet,
+as a proportion of the distance between two adjacent stems.")
      (before-line-breaking ,boolean? "Dummy property, used to trigger
 a callback function.")
      (between-cols ,pair? "Where to attach a loose column to.")

diff --git a/scm/define-grobs.scm b/scm/define-grobs.scm
index 4009f6ebdf10c208d280d8f6b923a1597e28997a..feca08ef5bf71dc0e0de247c201b07527b2a0aba 100644 (file)
--- a/scm/define-grobs.scm
+++ b/scm/define-grobs.scm
@@ -1638,6 +1638,8 @@
        (thickness . 1.3)
        (cross-staff . ,ly:stem::calc-cross-staff)
        (flag . ,ly:stem::calc-flag)
+       (beamlet-default-length . (1.0 . 1.0))
+       (beamlet-max-length-proportion . (0.5 . 0.5))
        (details
         . (
            ;; 3.5 (or 3 measured from note head) is standard length