trim example.

[lilypond.git] / lily / misc.cc

diff --git a/lily/misc.cc b/lily/misc.cc
index 38154556fd8efa4497254439578c5b9619121838..e7c3063df234c6ce79bca6185bf9358e837e401b 100644 (file)
--- a/lily/misc.cc
+++ b/lily/misc.cc
@@ -3,67 +3,55 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c)  1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
-    Jan Nieuwenhuizen <janneke@gnu.org>
+  (c) 1997--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
+  Jan Nieuwenhuizen <janneke@gnu.org>
 */
 
-#include <math.h>
+
 #include "misc.hh"
 
 /*
-  Return the 2-log, rounded down 
- */
+  Return the 2-log, rounded down
+*/
 int
 intlog2 (int d)
 {
   assert (d);
-  int i=0;
-  while ((d != 1)) 
+  int i = 0;
+  while ((d != 1))
     {
-      d/= 2;
+      d /= 2;
       i++;
     }
-  
-  assert (! (d/2));
+
+  assert (! (d / 2));
   return i;
 }
 
 double
 log_2 (double x)
 {
-  return log (x)  /log (2.0);
+  return log (x) / log (2.0);
 }
 
-
-static int
-comp (Real const &a, Real const &b)
+Real
+directed_round (Real f, Direction d)
 {
-  return sign (a-b);
+  if (d < 0)
+    return floor (f);
+  else
+    return ceil (f);
 }
 
-Interval
-quantise_iv (Array<Real> positions, Real x)
-{
-  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 Interval (positions[i] , positions[i+1]) + period * n;
+/*
+   0 at threshold,  1 at 0, with 1/x falloff.
+ */
+Real
+peak_around (Real epsilon,  Real threshold, Real x)
+{
+  if (x < 0)
+    return 1.0;
+  return max (- epsilon * (x - threshold) / ((x + epsilon)  * threshold), 0.0);
 }