* stepmake/aclocal.m4 (STEPMAKE_PANGO_FT2): Define HAVE_PANGO16 too.

[lilypond.git] / scm / beam.scm

diff --git a/scm/beam.scm b/scm/beam.scm
index f3d0de99517db0f091647a15c8c92307c21d6864..e92edc0e84c44a0fd5c060a1f6ad92c5cda1879c 100644 (file)
--- a/scm/beam.scm
+++ b/scm/beam.scm
@@ -3,13 +3,13 @@
 ;;;;
 ;;;; source file of the GNU LilyPond music typesetter
 ;;;; 
-;;;; (c) 2000--2001 Jan Nieuwenhuizen <janneke@gnu.org>
+;;;; (c) 2000--2005 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;;;
 
 ;;
 ;; width in staff space.
 ;;
-(define (default-beam-flag-width-function type)
+(define (beam-flag-width-function type)
   (cond
    ((eq? type 1) 1.98) 
    ((eq? type 1) 1.65) ;; FIXME: check what this should be and why
@@ -29,21 +29,87 @@
 ;;     
 ;; We have our doubts, so we simply provide all sensible alternatives.
 
+
+;;
+;; DOCME: what goes into this func, what comes out.
 (define (dir-compare up down)
   (sign (- up down)))
 
 ;; arguments are in the form (up . down)
-(define (beam-dir-majority count total)
+(define-public (beam-dir-majority count total)
   (dir-compare (car count) (cdr count)))
 
-(beam-dir-majority '(0 . 0) '(0 . 0))
+(define-public (beam-dir-majority-median count total)
+  "First try majority. If that doesn't work, try median."
+  (let ((maj (dir-compare (car count) (cdr count))))
+    (if (not (= maj 0))
+       maj
+       (beam-dir-median count total))))
 
-(define (beam-dir-mean count total)
+(define-public (beam-dir-mean count total)
   (dir-compare (car total) (cdr total)))
 
-(define (beam-dir-median count total)
+(define-public (beam-dir-median count total)
   (if (and (> (car count) 0)
           (> (cdr count) 0))
       (dir-compare (/ (car total) (car count)) (/ (cdr total) (cdr count)))
       (dir-compare (car count) (cdr count))))
-           
+
+(define ((check-beam-quant posl posr) beam)
+  "Check whether BEAM has POSL and POSR quants.  POSL are (POSITION
+. QUANT) pairs, where QUANT is -1 (hang), 0 (center), 1 (sit) or -2/ 2 (inter) 
+
+"
+  (let* ((posns (ly:grob-property beam 'positions))
+        (thick (ly:grob-property beam 'thickness))
+        (layout (ly:grob-layout beam))
+        (lthick (ly:output-def-lookup layout 'linethickness))
+        (staff-thick lthick) ; fixme.
+        (quant->coord (lambda (p q)
+                        (if (= 2 (abs q))
+                            (+ p (/ q 4.0))
+                            (+ p (- (* 0.5 q thick) (* 0.5 q lthick))))))
+        (want-l (quant->coord (car posl) (cdr posl))) 
+        (want-r (quant->coord (car posr) (cdr posr)))
+        (almost-equal (lambda (x y) (< (abs (- x y)) 1e-3))))
+    
+    (if (or (not (almost-equal want-l (car posns)))
+           (not (almost-equal want-r (cdr posns))))
+       (begin
+         (ly:warning (_ "Error in beam quanting.  Expected (~S,~S) found ~S.")
+                     want-l want-r posns)
+         (set! (ly:grob-property beam 'quant-score)
+               (format "(~S,~S)" want-l want-r)))
+       (set! (ly:grob-property beam 'quant-score) ""))))
+
+(define ((check-beam-slope-sign comparison) beam)
+  "Check whether the slope of BEAM is correct wrt. COMPARISON."
+  (let* ((posns (ly:grob-property beam 'positions))
+        (slope-sign (- (cdr posns) (car posns)))
+        (correct (comparison slope-sign 0)))
+
+    (if (not correct)
+       (begin
+         (ly:warning (_ "Error in beam quanting.  Expected ~S 0, found ~S.")
+                     (procedure-name comparison) "0" slope-sign)
+         (set! (ly:grob-property beam 'quant-score)
+               (format "~S 0" (procedure-name comparison))))
+       (set! (ly:grob-property beam 'quant-score) ""))))
+
+(define-public (check-quant-callbacks l r)
+  (list Beam::least_squares
+       Beam::check_concave
+       Beam::slope_damping
+       Beam::shift_region_to_valid
+       Beam::quanting
+       (check-beam-quant l r)))
+
+
+(define-public (check-slope-callbacks comparison)
+  (list Beam::least_squares
+       Beam::check_concave
+       Beam::slope_damping
+       Beam::shift_region_to_valid
+       Beam::quanting
+       (check-beam-slope-sign comparison)))
+