patch::: 1.5.18.moh1: [PATCH] 1.4 Lyric alignment

[lilypond.git] / lily / misc.cc

diff --git a/lily/misc.cc b/lily/misc.cc
index d150d557926ecc4ecd7293a03659cd7c9666d81f..45a055f8a6bb4841b2028da33e4309683573dd7f 100644 (file)
--- a/lily/misc.cc
+++ b/lily/misc.cc
@@ -3,45 +3,67 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c) 1997 Han-Wen Nienhuys <hanwen@stack.nl>
+  (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+    Jan Nieuwenhuizen <janneke@gnu.org>
 */
 
 #include <math.h>
-
-#include "item.hh"
 #include "misc.hh"
-#include "moment.hh"
 
+/*
+  Return the 2-log, rounded down 
+ */
 int
-intlog2(int d) {
+intlog2 (int d)
+{
+  assert (d);
   int i=0;
-  while (!(d&1)) 
+  while ((d != 1)) 
     {
-       d/= 2;
-       i++;
+      d/= 2;
+      i++;
     }
-  assert (!(d/2));
+  
+  assert (! (d/2));
   return i;
 }
 
 double
-log_2(double x) {
+log_2 (double x)
+{
   return log (x)  /log (2.0);
 }
 
-#if 1
+
+static int
+comp (Real const &a, Real const &b)
+{
+  return sign (a-b);
+}
+
 Interval
-itemlist_width (const Array<Item*> &its)
+quantise_iv (Array<Real> positions, Real x)
 {
-  Interval iv ;
-  iv.set_empty();
-   
-  for (int j =0; j < its.size(); j++)
-    {
-       iv.unite (its[j]->width());
+  positions.sort (comp);
+  Real period = positions.top () - positions[0];
+  
+  int n =  int ((x - positions[0]) / period);
+  Real frac = (x - positions[0]) -  n * period;
 
+  while (frac < 0)
+    {
+      frac += period;
+      n --;
+    }
+  
+  Real px = frac + positions[0];
+  assert (positions[0] <= px && px <= positions.top ());
+  int i=0;
+  for (; i < positions.size () - 1; i++)
+    {
+      if (positions[i] <= px && px <= positions[i+1])
+       break; 
     }
-  return iv;
-}
 
-#endif
+  return Interval (positions[i] , positions[i+1]) + period * n;
+}