From: Urs Liska <ul@openlilylib.org>
Date: Mon, 28 Dec 2015 15:01:33 +0000 (+0100)
Subject: 4704: Update LSR snippet for documentation
X-Git-Tag: release/2.19.35-1~9^2~3
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=4b994f8a;hp=9b8b5c2e05183a82ff687db186eb3eb3ff57f94e;p=lilypond.git

4704: Update LSR snippet for documentation
---

diff --git a/Documentation/snippets/new/subdividing-beams.ly b/Documentation/snippets/new/subdividing-beams.ly
new file mode 100644
index 0000000000..e614df5e86
--- /dev/null
+++ b/Documentation/snippets/new/subdividing-beams.ly
@@ -0,0 +1,54 @@
+\version "2.19.34"
+
+\header {
+  lsrtags = "rhythms"
+
+  texidoc = "
+The beams of consecutive 16th (or shorter) notes are, by default, not
+subdivided.  That is, the three (or more) beams stretch unbroken over
+entire groups of notes.  This behavior can be modified to subdivide the
+beams into sub-groups by setting the property @code{subdivideBeams}.
+When set, multiple beams will be subdivided at intervals defined by the
+current value of @code{baseMoment} by reducing the multiple beams to
+the number of beams that indicates the metric value of the subdivision. 
+If the group following the division is shorter than the current metric
+value (usually because the beam is incomplete) the number of beams
+reflects the longest possible subdivision group.  However, if there is
+only one note left after the division this restriction isn't applied.
+Note that @code{baseMoment} defaults to one over the denominator of the
+current time signature if not set explicitly. It must be set to a
+fraction giving the duration of the beam sub-group using the
+@code{ly:make-moment} function, as shown in this snippet. Also, when
+@code{baseMoment} is changed, @code{beatStructure} should also be
+changed to match the new @code{baseMoment}:
+
+"
+  doctitle = "Subdividing beams"
+} % begin verbatim
+
+\relative c'' {
+  c32[ c c c c c c c]
+  \set subdivideBeams = ##t
+  c32[ c c c c c c c]
+
+  % Set beam sub-group length to an eighth note
+  \set baseMoment = #(ly:make-moment 1/8)
+  \set beatStructure = #'(2 2 2 2)
+  c32[ c c c c c c c]
+
+  % Set beam sub-group length to a sixteenth note
+  \set baseMoment = #(ly:make-moment 1/16)
+  \set beatStructure = #'(4 4 4 4)
+  c32[ c c c c c c c]
+  
+  % Shorten beam by 1/32
+  \set baseMoment = #(ly:make-moment 1/8)
+  \set beatStructure = #'(2 2 2 2)
+  c32[ c c c c c c] r32
+  
+  % Shorten beam by 3/32
+  \set baseMoment = #(ly:make-moment 1/8)
+  \set beatStructure = #'(2 2 2 2)
+  c32[ c c c c] r16.
+  
+}