2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 1997--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
5 Jan Nieuwenhuizen <janneke@gnu.org>
7 LilyPond is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 LilyPond is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
28 Return the 2-log, rounded down
48 return log (x) / log (2.0);
52 directed_round (Real f, Direction d)
61 0 at threshold, 1 at 0, with 1/x falloff.
64 peak_around (Real epsilon, Real threshold, Real x)
68 return max (- epsilon * (x - threshold) / ((x + epsilon) * threshold), 0.0);
72 0 at 0, 1 at standard_x, and increasing thereafter.
75 convex_amplifier (Real standard_x, Real increase_factor, Real x)
77 return (exp (increase_factor * x / standard_x) - 1.0) / (exp (increase_factor) - 1.0);
81 camel_case_to_lisp_identifier (const string &in)
85 /* don't add '-' before first character */
86 out.push_back (char (tolower (in[0])));
88 for (size_t inpos = 1; inpos < in.size (); inpos++)
90 if (isupper (in[inpos]))
92 out.push_back ( char (tolower (in[inpos])));
95 string result (&out[0], out.size ());
96 replace_all (&result, '_', '-');
102 get_point_in_y_direction (Offset orig, Real slope, Real dist, Direction dir)
104 if (slope == infinity_f)
105 return orig + Offset (dir * dist, 0.0);
107 Real x = slope == 0.0 ? 1.0 * dir : 1.0 * sign (slope) * dir;
109 Real angle = atan2 (y, x);
111 complex<Real> orig_c (orig[X_AXIS], orig[Y_AXIS]);
112 complex<Real> to_move = polar (dist, angle);
113 complex<Real> res = orig_c + to_move;
115 return Offset (real (res), imag (res));