libs/ardour/ardour/utils.h

   1 /*
   2     Copyright (C) 1999 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #ifndef __ardour_utils_h__
  21 #define __ardour_utils_h__
  22
  23 #ifdef WAF_BUILD
  24 #include "libardour-config.h"
  25 #endif
  26
  27 #include <iostream>
  28 #include <string>
  29 #include <cmath>
  30
  31 #if __APPLE__
  32 #include <CoreFoundation/CoreFoundation.h>
  33 #endif /* __APPLE__ */
  34
  35 bool string_is_affirmative (const std::string&);
  36
  37 #include "ardour/ardour.h"
  38 #include "ardour/data_type.h"
  39 #include "ardour/dB.h"
  40
  41 class XMLNode;
  42
  43 std::string legalize_for_path (const std::string& str);
  44 XMLNode* find_named_node (const XMLNode& node, std::string name);
  45 std::string bool_as_string (bool);
  46
  47 static inline float f_max(float x, float a) {
  48         x -= a;
  49         x += fabsf (x);
  50         x *= 0.5f;
  51         x += a;
  52
  53         return (x);
  54 }
  55
  56 std::string bump_name_once(const std::string& s, char delimiter);
  57
  58 int cmp_nocase (const std::string& s, const std::string& s2);
  59
  60 int touch_file(std::string path);
  61
  62 std::string path_expand (std::string);
  63 std::string region_name_from_path (std::string path, bool strip_channels, bool add_channel_suffix = false, uint32_t total = 0, uint32_t this_one = 0);
  64 bool path_is_paired (std::string path, std::string& pair_base);
  65
  66 void compute_equal_power_fades (ARDOUR::framecnt_t nframes, float* in, float* out);
  67
  68 const char* sync_source_to_string (ARDOUR::SyncSource src, bool sh = false);
  69 ARDOUR::SyncSource string_to_sync_source (std::string str);
  70
  71 const char* edit_mode_to_string (ARDOUR::EditMode);
  72 ARDOUR::EditMode string_to_edit_mode (std::string);
  73
  74 #undef  OLD_GAIN_MATH
  75 #define OLD_GAIN_MATH
  76
  77 static inline double
  78 gain_to_slider_position (ARDOUR::gain_t g)
  79 {
  80         if (g == 0) return 0;
  81
  82 #ifndef OLD_GAIN_MATH
  83         /* Power Law With Exponential Cutoff 2D, fit to data from TC Spectra
  84            console (image of fader gradations
  85
  86            y = C * x(-T) * exp(-x/K)
  87
  88            C =  8.2857630370864188E-01
  89            T = -5.1526743785019269E-01
  90            K =  7.8990885960495589E+00
  91
  92          */
  93
  94         return 8.2857630370864188E-01 * pow(g,5.1526743785019269E-01) * exp (-g/7.8990885960495589E+00);
  95 #else
  96         return pow((6.0*log(g)/log(2.0)+192.0)/198.0, 8.0);
  97 #endif
  98 }
  99
 100 static inline ARDOUR::gain_t
 101 slider_position_to_gain (double pos)
 102 {
 103         if (pos == 0.0) {
 104                 return 0.0;
 105         }
 106
 107 #ifndef OLD_GAIN_MATH
 108         /* 5th order polynomial function fit to data from a TC Spectra console
 109            fader (image of fader gradations).
 110
 111            y = a + bx1 + cx2 + dx3 + fx4 + gx5
 112
 113            a = -1.1945480381045521E-02
 114            b =  1.5809476525537265E+00
 115            c = -1.5850710838966151E+01
 116            d =  6.1643128605961991E+01
 117            f = -8.5525246160607693E+01
 118            g =  4.1312725896188283E+01
 119
 120         */
 121
 122         double p = pos;
 123         double g = -1.1945480381045521E-02;
 124
 125         g +=  1.5809476525537265E+00 * pos;
 126         pos *= p;
 127         g += -1.5850710838966151E+01 * pos;
 128         pos *= p;
 129         g += 6.1643128605961991E+01 * pos;
 130         pos *= p;
 131         g += -8.5525246160607693E+01 * pos;
 132         pos *= p;
 133         g += 4.1312725896188283E+01 * pos;
 134
 135         return g;
 136 #else
 137         /* XXX Marcus writes: this doesn't seem right to me. but i don't have a better answer ... */
 138         if (pos == 0.0) return 0;
 139         return pow (2.0,(sqrt(sqrt(sqrt(pos)))*198.0-192.0)/6.0);
 140 #endif
 141 }
 142 #undef OLD_GAIN_MATH
 143
 144 double gain_to_slider_position_with_max (double g, double max_gain = 2.0);
 145 double slider_position_to_gain_with_max (double g, double max_gain = 2.0);
 146
 147 /* I don't really like hard-coding these falloff rates here
 148  * Probably should use a map of some kind that could be configured
 149  * These rates are db/sec.
 150 */
 151
 152 #define METER_FALLOFF_OFF     0.0f
 153 #define METER_FALLOFF_SLOWEST 6.6f // BBC standard
 154 #define METER_FALLOFF_SLOW    8.6f // BBC standard
 155 #define METER_FALLOFF_MEDIUM  20.0f
 156 #define METER_FALLOFF_FAST    32.0f
 157 #define METER_FALLOFF_FASTER  46.0f
 158 #define METER_FALLOFF_FASTEST 70.0f
 159
 160 float meter_falloff_to_float (ARDOUR::MeterFalloff);
 161 ARDOUR::MeterFalloff meter_falloff_from_float (float);
 162 float meter_falloff_to_db_per_sec (float);
 163
 164 const char* native_header_format_extension (ARDOUR::HeaderFormat, const ARDOUR::DataType& type);
 165 bool matching_unsuffixed_filename_exists_in (const std::string& dir, const std::string& name);
 166
 167 uint32_t how_many_dsp_threads ();
 168
 169 #if __APPLE__
 170 std::string CFStringRefToStdString(CFStringRef stringRef);
 171 #endif // __APPLE__
 172
 173 #endif /* __ardour_utils_h__ */
 174