2 Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
26 #define M_PI (3.14159265358979323846)
30 extern double db_to_linear (double db);
31 extern double linear_to_db (double linear);
33 /** @return linear gain according to a logarithmic curve, for fading in.
34 * t < 0: linear gain of 0
35 * 0 >= t >= 1: logarithmic fade in curve
36 * t > 1: linear gain of 1
38 extern float logarithmic_fade_in_curve (float t);
41 /** @return linear gain according to a logarithmic curve, for fading out.
42 * t > 1: linear gain of 0
43 * 0 >= t >= 1: logarithmic fade out curve
44 * t < 0: linear gain of 1
46 extern float logarithmic_fade_out_curve (float t);
50 T clamp (T val, T minimum, T maximum)
52 return std::max(std::min(val, maximum), minimum);