From 99904735e066804358f1d0bd138a84f1e9ecda91 Mon Sep 17 00:00:00 2001 From: David Robillard Date: Sun, 18 Mar 2007 06:07:08 +0000 Subject: Merged with trunk R1612. git-svn-id: svn://localhost/ardour2/branches/midi@1614 d708f5d6-7413-0410-9779-e7cbd77b26cf --- libs/surfaces/tranzport/slider_gain.h | 40 +++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 libs/surfaces/tranzport/slider_gain.h (limited to 'libs/surfaces/tranzport/slider_gain.h') diff --git a/libs/surfaces/tranzport/slider_gain.h b/libs/surfaces/tranzport/slider_gain.h new file mode 100644 index 0000000000..1bb497178f --- /dev/null +++ b/libs/surfaces/tranzport/slider_gain.h @@ -0,0 +1,40 @@ +/* + * Copyright (C) 2006 Paul Davis + * Copyright (C) 2007 Michael Taht + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * */ + +#ifndef ardour_slider_gain +#define ardour_slider_gain + +static inline double +gain_to_slider_position (ARDOUR::gain_t g) +{ + if (g == 0) return 0; + return pow((6.0*log(g)/log(2.0)+192.0)/198.0, 8.0); + +} + +static inline ARDOUR::gain_t +slider_position_to_gain (double pos) +{ + /* XXX Marcus writes: this doesn't seem right to me. but i don't have a better answer ... */ + if (pos == 0.0) return 0; + return pow (2.0,(sqrt(sqrt(sqrt(pos)))*198.0-192.0)/6.0); +} + +#endif -- cgit v1.2.3