From cb20a87a5875c0f9d4c7550e831db2d03bc9a41c Mon Sep 17 00:00:00 2001
From: Mike Solomon <mike@apollinemike.com>
Date: Fri, 28 Oct 2011 13:51:40 +0200
Subject: [PATCH] Adds Scheme bindings for Spring constructor and setters.

---
 lily/spring-smob.cc | 38 ++++++++++++++++++++++++++++++++++++++
 scm/lily.scm        |  1 +
 2 files changed, 39 insertions(+)

diff --git a/lily/spring-smob.cc b/lily/spring-smob.cc
index 8e263d0694..0f22f06778 100644
--- a/lily/spring-smob.cc
+++ b/lily/spring-smob.cc
@@ -42,3 +42,41 @@ Spring::equal_p (SCM a, SCM b)
   return a == b ? SCM_BOOL_T : SCM_BOOL_F;
 }
 
+LY_DEFINE (ly_make_spring, "ly:make-spring",
+           2, 0, 0, (SCM ideal, SCM min_dist),
+           "Make a spring.  @var{ideal} is the ideal distance of the"
+           " spring, and @var{min-dist} is the minimum distance.")
+{
+  LY_ASSERT_TYPE (scm_is_number, ideal, 1);
+  LY_ASSERT_TYPE (scm_is_number, min_dist, 2);
+
+  Spring s (scm_to_double (ideal), scm_to_double (min_dist));
+
+  return s.smobbed_copy ();
+}
+
+LY_DEFINE (ly_spring_set_inverse_compress_strength_x, "ly:spring-set-inverse-compress-strength!",
+           2, 0, 0, (SCM spring, SCM strength),
+           "Set the inverse compress @var{strength} of @var{spring}.")
+{
+  LY_ASSERT_SMOB (Spring, spring, 1);
+  LY_ASSERT_TYPE (scm_is_number, strength, 2);
+
+  Spring *s = unsmob_spring (spring);
+  s->set_inverse_compress_strength (scm_to_double (strength));
+  return s->smobbed_copy ();
+}
+
+LY_DEFINE (ly_spring_set_inverse_stretch_strength_x, "ly:spring-set-inverse-stretch-strength!",
+           2, 0, 0, (SCM spring, SCM strength),
+           "Set the inverse stretch @var{strength} of @var{spring}.")
+{
+  LY_ASSERT_SMOB (Spring, spring, 1);
+  LY_ASSERT_TYPE (scm_is_number, strength, 2);
+
+  Spring *s = unsmob_spring (spring);
+  s->set_inverse_stretch_strength (scm_to_double (strength));
+  return s->smobbed_copy ();
+}
+
+IMPLEMENT_TYPE_P (Spring, "ly:spring?");
\ No newline at end of file
diff --git a/scm/lily.scm b/scm/lily.scm
index 90df1f6a09..3ad7fb580e 100644
--- a/scm/lily.scm
+++ b/scm/lily.scm
@@ -563,6 +563,7 @@ LilyPond safe mode.  The syntax is the same as `define*-public'."
     (,ly:skyline-pair? . "pair of skylines")
     (,ly:source-file? . "source file")
     (,ly:spanner? . "spanner")
+    (,ly:spring? . "spring")
     (,ly:stencil? . "stencil")
     (,ly:stream-event? . "stream event")
     (,ly:translator? . "translator")
-- 
2.39.2