libs/fluidsynth/src/fluid_rvoice.h

   1 /* FluidSynth - A Software Synthesizer
   2  *
   3  * Copyright (C) 2003  Peter Hanappe and others.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public License
   7  * as published by the Free Software Foundation; either version 2.1 of
   8  * the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free
  17  * Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  */
  20
  21
  22 #ifndef _FLUID_RVOICE_H
  23 #define _FLUID_RVOICE_H
  24
  25 #include "fluidsynth_priv.h"
  26 #include "fluid_iir_filter.h"
  27 #include "fluid_adsr_env.h"
  28 #include "fluid_lfo.h"
  29 #include "fluid_phase.h"
  30 #include "fluid_sfont.h"
  31
  32 typedef struct _fluid_rvoice_envlfo_t fluid_rvoice_envlfo_t;
  33 typedef struct _fluid_rvoice_dsp_t fluid_rvoice_dsp_t;
  34 typedef struct _fluid_rvoice_buffers_t fluid_rvoice_buffers_t;
  35 typedef struct _fluid_rvoice_t fluid_rvoice_t;
  36
  37 /* Smallest amplitude that can be perceived (full scale is +/- 0.5)
  38  * 16 bits => 96+4=100 dB dynamic range => 0.00001
  39  * 24 bits => 144-4 = 140 dB dynamic range => 1.e-7
  40  * 1.e-7 * 2 == 2.e-7 :)
  41  */
  42 #define FLUID_NOISE_FLOOR 2.e-7
  43
  44 enum fluid_loop
  45 {
  46     FLUID_UNLOOPED = 0,
  47     FLUID_LOOP_DURING_RELEASE = 1,
  48     FLUID_NOTUSED = 2,
  49     FLUID_LOOP_UNTIL_RELEASE = 3
  50 };
  51
  52 /*
  53  * rvoice ticks-based parameters
  54  * These parameters must be updated even if the voice is currently quiet.
  55  */
  56 struct _fluid_rvoice_envlfo_t
  57 {
  58     /* Note-off minimum length */
  59     unsigned int ticks;
  60     unsigned int noteoff_ticks;
  61
  62     /* vol env */
  63     fluid_adsr_env_t volenv;
  64
  65     /* mod env */
  66     fluid_adsr_env_t modenv;
  67     fluid_real_t modenv_to_fc;
  68     fluid_real_t modenv_to_pitch;
  69
  70     /* mod lfo */
  71     fluid_lfo_t modlfo;
  72     fluid_real_t modlfo_to_fc;
  73     fluid_real_t modlfo_to_pitch;
  74     fluid_real_t modlfo_to_vol;
  75
  76     /* vib lfo */
  77     fluid_lfo_t viblfo;
  78     fluid_real_t viblfo_to_pitch;
  79 };
  80
  81 /*
  82  * rvoice parameters needed for dsp interpolation
  83  */
  84 struct _fluid_rvoice_dsp_t
  85 {
  86     /* interpolation method, as in fluid_interp in fluidsynth.h */
  87     enum fluid_interp interp_method;
  88     enum fluid_loop samplemode;
  89
  90     /* Flag that is set as soon as the first loop is completed. */
  91     char has_looped;
  92
  93     /* Flag that initiates, that sample-related parameters have to be checked. */
  94     char check_sample_sanity_flag;
  95
  96     fluid_sample_t *sample;
  97
  98     /* sample and loop start and end points (offset in sample memory).  */
  99     int start;
 100     int end;
 101     int loopstart;
 102     int loopend;        /* Note: first point following the loop (superimposed on loopstart) */
 103
 104     /* Stuff needed for portamento calculations */
 105     fluid_real_t pitchoffset;        /* the portamento range in midicents */
 106     fluid_real_t pitchinc;           /* the portamento increment in midicents */
 107
 108     /* Stuff needed for phase calculations */
 109
 110     fluid_real_t pitch;              /* the pitch in midicents */
 111     fluid_real_t root_pitch_hz;
 112     fluid_real_t output_rate;
 113
 114     /* Stuff needed for amplitude calculations */
 115
 116     fluid_real_t attenuation;        /* the attenuation in centibels */
 117     fluid_real_t prev_attenuation;   /* the previous attenuation in centibels
 118                                         used by fluid_rvoice_multi_retrigger_attack() */
 119     fluid_real_t min_attenuation_cB; /* Estimate on the smallest possible attenuation
 120                                           * during the lifetime of the voice */
 121     fluid_real_t amplitude_that_reaches_noise_floor_nonloop;
 122     fluid_real_t amplitude_that_reaches_noise_floor_loop;
 123     fluid_real_t synth_gain;    /* master gain */
 124
 125     /* Dynamic input to the interpolator below */
 126
 127     fluid_real_t amp;                /* current linear amplitude */
 128     fluid_real_t amp_incr;              /* amplitude increment value for the next FLUID_BUFSIZE samples */
 129
 130     fluid_phase_t phase;             /* the phase (current sample offset) of the sample wave */
 131     fluid_real_t phase_incr;    /* the phase increment for the next FLUID_BUFSIZE samples */
 132 };
 133
 134 /* Currently left, right, reverb, chorus. To be changed if we
 135    ever add surround positioning, or stereo reverb/chorus */
 136 #define FLUID_RVOICE_MAX_BUFS (4)
 137
 138 /*
 139  * rvoice mixer-related parameters
 140  */
 141 struct _fluid_rvoice_buffers_t
 142 {
 143     unsigned int count; /* Number of records in "bufs" */
 144     struct
 145     {
 146         fluid_real_t amp;
 147         int mapping; /* Mapping to mixdown buffer index */
 148     } bufs[FLUID_RVOICE_MAX_BUFS];
 149 };
 150
 151
 152 /*
 153  * Hard real-time parameters needed to synthesize a voice
 154  */
 155 struct _fluid_rvoice_t
 156 {
 157     fluid_rvoice_envlfo_t envlfo;
 158     fluid_rvoice_dsp_t dsp;
 159     fluid_iir_filter_t resonant_filter; /* IIR resonant dsp filter */
 160     fluid_iir_filter_t resonant_custom_filter; /* optional custom/general-purpose IIR resonant filter */
 161     fluid_rvoice_buffers_t buffers;
 162 };
 163
 164
 165 int fluid_rvoice_write(fluid_rvoice_t *voice, fluid_real_t *dsp_buf);
 166
 167 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_buffers_set_amp);
 168 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_buffers_set_mapping);
 169
 170 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_noteoff);
 171 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_voiceoff);
 172 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_reset);
 173 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_multi_retrigger_attack);
 174 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_portamento);
 175 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_output_rate);
 176 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_interp_method);
 177 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_root_pitch_hz);
 178 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_pitch);
 179 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_attenuation);
 180 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_min_attenuation_cB);
 181 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_viblfo_to_pitch);
 182 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_modlfo_to_pitch);
 183 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_modlfo_to_vol);
 184 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_modlfo_to_fc);
 185 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_modenv_to_fc);
 186 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_modenv_to_pitch);
 187 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_synth_gain);
 188 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_start);
 189 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_end);
 190 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_loopstart);
 191 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_loopend);
 192 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_samplemode);
 193 DECLARE_FLUID_RVOICE_FUNCTION(fluid_rvoice_set_sample);
 194
 195 /* defined in fluid_rvoice_dsp.c */
 196 void fluid_rvoice_dsp_config(void);
 197 int fluid_rvoice_dsp_interpolate_none(fluid_rvoice_dsp_t *voice, fluid_real_t *FLUID_RESTRICT dsp_buf, int is_looping);
 198 int fluid_rvoice_dsp_interpolate_linear(fluid_rvoice_dsp_t *voice, fluid_real_t *FLUID_RESTRICT dsp_buf, int is_looping);
 199 int fluid_rvoice_dsp_interpolate_4th_order(fluid_rvoice_dsp_t *voice, fluid_real_t *FLUID_RESTRICT dsp_buf, int is_looping);
 200 int fluid_rvoice_dsp_interpolate_7th_order(fluid_rvoice_dsp_t *voice, fluid_real_t *FLUID_RESTRICT dsp_buf, int is_looping);
 201
 202
 203 /*
 204  * Combines the most significant 16 bit part of a sample with a potentially present
 205  * least sig. 8 bit part in order to create a 24 bit sample.
 206  */
 207 static FLUID_INLINE int32_t
 208 fluid_rvoice_get_sample(const short int *dsp_msb, const char *dsp_lsb, unsigned int idx)
 209 {
 210     /* cast sample to unsigned type, so we can safely shift and bitwise or
 211      * without relying on undefined behaviour (should never happen anyway ofc...) */
 212     uint32_t msb = (uint32_t)dsp_msb[idx];
 213     uint8_t lsb = 0U;
 214
 215     /* most soundfonts have 16 bit samples, assume that it's unlikely we
 216      * experience 24 bit samples here */
 217     if(FLUID_UNLIKELY(dsp_lsb != NULL))
 218     {
 219         lsb = (uint8_t)dsp_lsb[idx];
 220     }
 221
 222     return (int32_t)((msb << 8) | lsb);
 223 }
 224
 225 #endif