Issue 4294: Functions to display rhythmic information of a grob

[lilypond.git] / scm / output-lib.scm

diff --git a/scm/output-lib.scm b/scm/output-lib.scm
index 0250271250d9b7f0da8a6e6a4c84aef58ff87146..96456b1b77fb436ae4a90b6b7ae851c30fa01678 100644 (file)
--- a/scm/output-lib.scm
+++ b/scm/output-lib.scm
@@ -1,6 +1,6 @@
 ;;;; This file is part of LilyPond, the GNU music typesetter.
 ;;;;
-;;;; Copyright (C) 1998--2014 Jan Nieuwenhuizen <janneke@gnu.org>
+;;;; Copyright (C) 1998--2015 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;;; Han-Wen Nienhuys <hanwen@xs4all.nl>
 ;;;;
 ;;;; LilyPond is free software: you can redistribute it and/or modify
@@ -26,6 +26,33 @@
 (define-public (grob::is-live? grob)
   (pair? (ly:grob-basic-properties grob)))
 
+(define-public (grob::name grob)
+  "Return the name of the grob @var{grob} as a symbol."
+  (assq-ref (ly:grob-property grob 'meta) 'name))
+
+(define-public (grob::rhythmic-location grob)
+  "Return a pair consisting of the measure number and moment within
+   the measure of grob @var{grob}."
+  (let* (; all grobs support either spanner- or item-interface
+         (item (if (grob::has-interface grob 'spanner-interface)
+                   (ly:spanner-bound grob LEFT)
+                   grob))
+         (col (ly:item-get-column item)))
+    (if (ly:grob? col)
+        (ly:grob-property col 'rhythmic-location)
+        '())))
+
+(define-public (grob::when grob)
+  "Return the global timestep (a moment) of grob @var{grob}."
+  (let* (; all grobs support either spanner- or item-interface
+         (item (if (grob::has-interface grob 'spanner-interface)
+                   (ly:spanner-bound grob LEFT)
+                   grob))
+         (col (ly:item-get-column item)))
+    (if (ly:grob? col)
+        (ly:grob-property col 'when)
+        '())))
+
 (define-public (make-stencil-boxer thickness padding callback)
   "Return function that adds a box around the grob passed as argument."
   (lambda (grob)
@@ -1157,17 +1184,20 @@ parent or the parent has no setting."
 
 (define-public (script-interface::calc-x-offset grob)
   (ly:grob-property grob 'positioning-done)
-  (let* ((shift (ly:grob-property grob 'toward-stem-shift 0.0))
+  (let* ((shift-when-alone (ly:grob-property grob 'toward-stem-shift 0.0))
+         (shift-in-column (ly:grob-property grob 'toward-stem-shift-in-column))
+         (script-column (ly:grob-object grob 'script-column))
+         (shift (if (and (ly:grob? script-column) (number? shift-in-column))
+                    shift-in-column shift-when-alone))
          (note-head-location
           (ly:self-alignment-interface::aligned-on-x-parent grob))
          (note-head-grob (ly:grob-parent grob X))
          (stem-grob (ly:grob-object note-head-grob 'stem)))
 
     (+ note-head-location
-       ;; If the property 'toward-stem-shift is defined and the script
-       ;; has the same direction as the stem, move the script accordingly.
-       ;; Since scripts can also be over skips, we need to check whether
-       ;; the grob has a stem at all.
+       ;; If the script has the same direction as the stem, move the script
+       ;; in accordance with the value of 'shift'.  Since scripts can also be
+       ;; over skips, we need to check whether the grob has a stem at all.
        (if (ly:grob? stem-grob)
            (let ((dir1 (ly:grob-property grob 'direction))
                  (dir2 (ly:grob-property stem-grob 'direction)))
@@ -1364,7 +1394,7 @@ parent or the parent has no setting."
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; measure counter
 
-(define (measure-counter-stencil grob)
+(define-public (measure-counter-stencil grob)
   "Print a number for a measure count.  The number is centered using
 the extents of @code{BreakAlignment} grobs associated with the left and
 right bounds of a @code{MeasureCounter} spanner.  Broken measures are