source file of the GNU LilyPond music typesetter
- (c) 1997--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
- Jan Nieuwenhuizen <janneke@gnu.org>
+ (c) 1997--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
+ Jan Nieuwenhuizen <janneke@gnu.org>
*/
-#include <math.h>
#include "misc.hh"
-#ifndef STANDALONE
-#include "item.hh"
-#endif
-
+/*
+ Return the 2-log, rounded down
+*/
int
-intlog2(int d) {
- int i=0;
- while (!(d&1))
+intlog2 (int d)
+{
+ assert (d);
+ int i = 0;
+ while ((d != 1))
{
- d/= 2;
- i++;
+ d /= 2;
+ i++;
}
- assert (!(d/2));
+
+ assert (! (d / 2));
return i;
}
double
-log_2(double x) {
- return log (x) /log (2.0);
+log_2 (double x)
+{
+ return log (x) / log (2.0);
}
-
-/*
- TODO
- group in some Array_*
- make more generic / templatise
- */
-int
-get_lower_bound (Array<Real> const& positions, Real x)
+Real
+directed_round (Real f, Direction d)
{
- if (x < positions[0])
- return 0;
- for (int i = 1; i < positions.size (); i++)
- if (x < positions[i])
- return i - 1;
- return positions.size () - 1;
+ if (d < 0)
+ return floor (f);
+ else
+ return ceil (f);
}
-Slice
-get_bounds_slice (Array<Real> const& positions, Real x)
+
+
+/*
+ 0 at threshold, 1 at 0, with 1/x falloff.
+ */
+Real
+peak_around (Real epsilon, Real threshold, Real x)
{
- int l = get_lower_bound (positions, x);
- int u = positions.size () - 1 <? l + 1;
- if (x < positions[l])
- u = l;
- return Slice (l, u);
+ if (x < 0)
+ return 1.0;
+ return max (- epsilon * (x - threshold) / ((x + epsilon) * threshold), 0.0);
}
-Interval
-get_bounds_iv (Array<Real> const& positions, Real x)
+/*
+ 0 at 0, 1 at standard_x, and increasing thereafter.
+ */
+Real
+convex_amplifier (Real standard_x, Real increase_factor, Real x)
{
- Slice slice = get_bounds_slice (positions, x);
- return Interval (positions[slice[SMALLER]], positions[slice[BIGGER]]);
+ return (exp (increase_factor * x / standard_x) - 1.0) / (exp (increase_factor) - 1.0);
}
-// silly name
-Interval
-quantise_iv (Array<Real> const& positions, Real period, Real x)
+string
+camel_case_to_lisp_identifier (string in)
{
- /*
- ugh
- assume that
- * positions are sorted,
- * positions are nonnegative
- * period starts at zero
- */
-
- int n = (int)(x / period);
- Real frac = (x / period - n) * period;
- if (frac < 0)
+ vector<char> out;
+
+ /* don't add '-' before first character */
+ out.push_back (tolower (in[0]));
+
+ for (size_t inpos = 1; inpos < in.size (); inpos++)
{
- frac += period;
- n--;
+ if (isupper (in[inpos]))
+ out.push_back ('-');
+ out.push_back (tolower (in[inpos]));
}
+
+ string result (&out[0], out.size ());
+ replace_all (result, '_', '-');
- Slice slice = get_bounds_slice (positions, frac);
- Interval iv(positions[slice[SMALLER]], positions[slice[BIGGER]]);
-
- if (slice[SMALLER] == slice[BIGGER])
- {
- if (slice[SMALLER] == 0)
- iv[SMALLER] = - period + positions.top ();
- else
- iv[BIGGER] = period + positions[0];
- }
-
- iv += period * n;
-
- return iv;
+ return result;
}
+