X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fsimple-spacer-scheme.cc;h=48f127bfca5ae710b5778c73b343e6d08e994839;hb=b80683cc94b0c22bbe3fccb94a9b2e23787fd10b;hp=6f7610670670be53853887ddd0818cafbef02a11;hpb=c3ff1c6cd20e15e9036ee7120012e05b1d62a46d;p=lilypond.git

diff --git a/lily/simple-spacer-scheme.cc b/lily/simple-spacer-scheme.cc
index 6f76106706..48f127bfca 100644
--- a/lily/simple-spacer-scheme.cc
+++ b/lily/simple-spacer-scheme.cc
@@ -15,13 +15,19 @@
 
 LY_DEFINE (ly_solve_spring_rod_problem, "ly:solve-spring-rod-problem",
 	   4, 1, 0, (SCM springs, SCM rods, SCM length, SCM ragged),
-	   "Solve a spring and rod problem for @var{count} objects, that "
-	   "are connected by @var{count-1} springs, and an arbitrary number of rods "
-	   "Springs have the format (ideal, hooke) and rods (idx1, idx2, distance) "
-	   "@var{length} is a number, @var{ragged} a boolean "
-	   "Return: a list containing the force (positive for stretching, "
-	   "negative for compressing and #f for non-satisfied constraints) "
-	   "followed by the @var{spring-count}+1 positions of the objects. ")
+	   "Solve a spring and rod problem for @var{count} objects, that"
+	   " are connected by @var{count}-1 @var{springs}, and an arbitrary"
+	   " number of @var{rods}.  @var{count} is implicitly given by"
+	   " @var{springs} and @var{rods}.  The @var{springs} argument has"
+	   " the format @code{(ideal, inverse_hook)} and @var{rods} is of"
+	   " the form @code{(idx1, idx2, distance)}.\n"
+	   "\n"
+	   "@var{length} is a number, @var{ragged} a boolean.\n"
+	   "\n"
+	   "The function returns a list containing the force (positive for"
+	   " stretching, negative for compressing and @code{#f} for"
+	   " non-satisfied constraints) followed by @var{spring-count}+1"
+	   " positions of the objects.")
 {
   int len = scm_ilength (springs);
   if (len == 0)
@@ -36,9 +42,13 @@ LY_DEFINE (ly_solve_spring_rod_problem, "ly:solve-spring-rod-problem",
   for (SCM s = springs; scm_is_pair (s); s = scm_cdr (s))
     {
       Real ideal = scm_to_double (scm_caar (s));
-      Real hooke = scm_to_double (scm_cadar (s));
+      Real inv_hooke = scm_to_double (scm_cadar (s));
 
-      spacer.add_spring (ideal, 1 / hooke);
+      Spring sp (ideal, 0.0);
+      sp.set_inverse_compress_strength (inv_hooke);
+      sp.set_inverse_stretch_strength (inv_hooke);
+
+      spacer.add_spring (sp);
     }
 
   for (SCM s = rods; scm_is_pair (s); s = scm_cdr (s))