Change the treatment of min-distance in springs.

Previously, we ensured that the ideal distance was at least
as large as the minimum distance, but it sometimes useful
not to. Now, if a spring has minimum distance larger than
ideal distance, it will remain fixed (at minimum-distance)
for a while as you start to stretch it, but it will stretch
eventually. This helps give us a more uniform vertical
spacing.

1 files changed, 4 insertions, 2 deletions

diff --git a/lily/simple-spacer.cc b/lily/simple-spacer.cc
index 1d38d9a70f..bab2a05dcb 100644
--- a/lily/simple-spacer.cc
+++ b/lily/simple-spacer.cc
@@ -216,7 +216,9 @@ Simple_spacer::compress_line ()
     {
       Spring sp = sorted_springs[i];
 
-      assert (sp.blocking_force () <= cur_force);
+      if (sp.blocking_force () > cur_force)
+	continue;
+
       if (isinf (sp.blocking_force ()))
 	break;
 
@@ -234,7 +236,7 @@ Simple_spacer::compress_line ()
 	}
       
       cur_len -= block_dist;
-      inv_hooke -= sp.inverse_compress_strength ();
+      inv_hooke -= compressed ? sp.inverse_compress_strength () : sp.inverse_stretch_strength ();
       cur_force = sp.blocking_force ();
     }