Fix crash on stemlets without a head.

[lilypond.git] / scm / stencil.scm

diff --git a/scm/stencil.scm b/scm/stencil.scm
index 127a5f62ad95f442c3ae090d6cdae6ee03c0d3d4..536425b9c680ce5a44b0c7bcbe9f8924d94142fd 100644 (file)
--- a/scm/stencil.scm
+++ b/scm/stencil.scm
@@ -2,7 +2,7 @@
 ;;;;
 ;;;;  source file of the GNU LilyPond music typesetter
 ;;;; 
-;;;; (c) 2003--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
+;;;; (c) 2003--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
 (define-public (stack-stencils axis dir padding stils)
   "Stack stencils STILS in direction AXIS, DIR, using PADDING."
@@ -129,6 +129,24 @@ encloses the contents.
                            (interval-center x-ext)
                            (interval-center y-ext))))))
 
+(define-public (rounded-box-stencil stencil thickness padding blot)
+   "Add a rounded box around STENCIL, producing a new stencil."  
+
+  (let* ((xext (interval-widen (ly:stencil-extent stencil 0) padding))
+        (yext (interval-widen (ly:stencil-extent stencil 1) padding))
+   (min-ext (min (-(cdr xext) (car xext)) (-(cdr yext) (car yext))))
+   (ideal-blot (min blot (/ min-ext 2)))
+   (ideal-thickness (min thickness (/ min-ext 2)))
+        (outer (ly:round-filled-box
+            (interval-widen xext ideal-thickness) 
+            (interval-widen yext ideal-thickness) 
+               ideal-blot))
+        (inner (ly:make-stencil (list 'color (x11-color 'white) 
+            (ly:stencil-expr (ly:round-filled-box 
+               xext yext (- ideal-blot ideal-thickness)))))))
+    (set! stencil (ly:stencil-add outer inner))
+    stencil))
+
 
 (define-public (fontify-text font-metric text)
   "Set TEXT with font FONT-METRIC, returning a stencil."