/[svn]/linuxsampler/trunk/src/engines/gig/EGADSR.cpp
ViewVC logotype

Diff of /linuxsampler/trunk/src/engines/gig/EGADSR.cpp

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 237 by senkov, Sun Sep 12 01:59:40 2004 UTC revision 2408 by persson, Sat Feb 2 08:22:49 2013 UTC
# Line 3  Line 3 
3   *   LinuxSampler - modular, streaming capable sampler                     *   *   LinuxSampler - modular, streaming capable sampler                     *
4   *                                                                         *   *                                                                         *
5   *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *   *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
6     *   Copyright (C) 2005 - 2013 Christian Schoenebeck                       *
7   *                                                                         *   *                                                                         *
8   *   This program is free software; you can redistribute it and/or modify  *   *   This program is free software; you can redistribute it and/or modify  *
9   *   it under the terms of the GNU General Public License as published by  *   *   it under the terms of the GNU General Public License as published by  *
# Line 22  Line 23 
23    
24  #include "EGADSR.h"  #include "EGADSR.h"
25    
26    #include "../../common/global_private.h"
27    
28  namespace LinuxSampler { namespace gig {  namespace LinuxSampler { namespace gig {
29    
30      EGADSR::EGADSR(gig::Engine* pEngine, Event::destination_t ModulationDestination) {      void EGADSR::update(event_t Event, uint SampleRate) {
31          this->pEngine = pEngine;          if (atEnd(Event)) return;
         this->ModulationDestination = ModulationDestination;  
         Stage = stage_end;  
         Level = 0.0;  
     }  
   
     /**  
      * Will be called by the voice for every audio fragment to let the EG  
      * queue it's modulation changes for the current audio fragment.  
      *  
      * @param Samples       - total number of sample points to be rendered in this  
      *                        audio fragment cycle by the audio engine  
      * @param pEvents       - event list with "release" and "cancel release" events  
      * @param pTriggerEvent - event that caused triggering of the voice (only if  
      *                        the voices was triggered in the current audio  
      *                        fragment, NULL otherwise)  
      * @param SamplePos     - current playback position  
      * @param CurrentPitch  - current pitch value for playback  
      */  
     void EGADSR::Process(uint Samples, RTEList<Event>* pEvents, Event* pTriggerEvent, double SamplePos, double CurrentPitch) {  
         Event* pTransitionEvent;  
         if (pTriggerEvent) {  
             pEvents->set_current(pTriggerEvent);  
             pTransitionEvent = pEvents->next();  
         }  
         else {  
             pTransitionEvent = pEvents->first();  
         }  
32    
33          int iSample = TriggerDelay;          if (Event == event_hold_end) HoldAttack = false;
34          while (iSample < Samples) {  
35              switch (Stage) {          switch (Stage) {
36                  case stage_attack: {              case stage_attack:
37                      TriggerDelay = 0;                  switch (Event) {
38                      int to_process   = RTMath::Min(AttackStepsLeft, Samples - iSample);                      case event_release:
39                      int process_end  = iSample + to_process;                          enterReleasePart1Stage();
40                      AttackStepsLeft -= to_process;                          break;
41                      while (iSample < process_end) {                      case event_stage_end:
42                          Level += AttackCoeff;                          if (HoldAttack)
43                          pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;                              enterAttackHoldStage();
44                      }                          else
45                      if (iSample == Samples) { // postpone last transition event for the next audio fragment                              enterDecay1Part1Stage(SampleRate);
46                          Event* pLastEvent = pEvents->last();                          break;
                         if (pLastEvent) ReleasePostponed = (pLastEvent->Type == Event::type_release);  
                     }  
                     if (!AttackStepsLeft) Stage = (ReleasePostponed) ? stage_release : (HoldAttack) ? stage_attack_hold : stage_decay1;  
                     break;  
47                  }                  }
48                  case stage_attack_hold: {                  break;
49                      if (SamplePos >= LoopStart) {              case stage_attack_hold:
50                          Stage = stage_decay1;                  switch (Event) {
51                        case event_stage_end: {// just refresh time
52                            const int intMax = (unsigned int) -1 >> 1;
53                            StepsLeft = intMax; // we use the highest possible value
54                          break;                          break;
55                      }                      }
56                      int holdstepsleft = (int) (LoopStart - SamplePos / CurrentPitch); // FIXME: just an approximation, inaccuracy grows with higher audio fragment size, sufficient for usual fragment sizes though                      case event_hold_end:
57                      int to_process    = RTMath::Min(holdstepsleft, Samples - iSample);                          enterDecay1Part1Stage(SampleRate);
58                      int process_end   = iSample + to_process;                          break;
59                      if (pTransitionEvent && pTransitionEvent->FragmentPos() <= process_end) {                      case event_release:
60                          process_end      = pTransitionEvent->FragmentPos();                          enterReleasePart1Stage();
61                          Stage            = (pTransitionEvent->Type == Event::type_release) ? stage_release : (InfiniteSustain) ? stage_sustain : stage_decay2;                          break;
                         pTransitionEvent = pEvents->next();  
                     }  
                     else if (to_process == holdstepsleft) Stage = stage_decay1;  
                     while (iSample < process_end) {  
                         pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;  
                     }  
                     break;  
62                  }                  }
63                  case stage_decay1: {                  break;
64                      int to_process   = RTMath::Min(Samples - iSample, Decay1StepsLeft);              case stage_decay1_part1:
65                      int process_end  = iSample + to_process;                  switch (Event) {
66                      if (pTransitionEvent && pTransitionEvent->FragmentPos() <= process_end) {                      case event_stage_end:
67                          process_end      = pTransitionEvent->FragmentPos();                          enterDecay1Part2Stage(SampleRate);
68                          Stage            = (pTransitionEvent->Type == Event::type_release) ? stage_release : (InfiniteSustain) ? stage_sustain : stage_decay2;                          break;
69                          pTransitionEvent = pEvents->next();                      case event_release:
70                      }                          enterReleasePart1Stage();
71                      else {                          break;
                         Decay1StepsLeft -= to_process;  
                         if (!Decay1StepsLeft) Stage = (InfiniteSustain) ? stage_sustain : stage_decay2;  
                     }  
                     while (iSample < process_end) {  
                         Level += Level * Decay1Coeff;  
                         pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;  
                     }  
                     break;  
72                  }                  }
73                  case stage_decay2: {                  break;
74                      int process_end;              case stage_decay1_part2:
75                      if (pTransitionEvent && pTransitionEvent->Type == Event::type_release && pTransitionEvent->FragmentPos() <= Samples) {                  switch (Event) {
76                          process_end      = pTransitionEvent->FragmentPos();                      case event_release:
77                          pTransitionEvent = pEvents->next();                          enterReleasePart1Stage();
78                          Stage            = stage_release; // switch to release stage soon                          break;
79                      }                      case event_stage_end:
80                      else process_end = Samples;                          if (Level < CONFIG_EG_BOTTOM)
81                      while (iSample < process_end) {                              enterEndStage();
82                          Level += Level * Decay2Coeff;                          else if (InfiniteSustain)
83                          pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;                              enterSustainStage();
84                      }                          else
85                      if (Level <= EG_ENVELOPE_LIMIT) Stage = stage_end;                              enterDecay2Stage(SampleRate);
86                      break;                          break;
87                  }                  }
88                  case stage_sustain: {                  break;
89                      int process_end;              case stage_decay2:
90                      if (pTransitionEvent && pTransitionEvent->Type == Event::type_release && pTransitionEvent->FragmentPos() <= Samples) {                  switch (Event) {
91                          process_end      = pTransitionEvent->FragmentPos();                      case event_stage_end:
92                          pTransitionEvent = pEvents->next();                          enterFadeOutStage();
93                          Stage            = stage_release; // switch to release stage soon                          break;
94                      }                      case event_release:
95                      else process_end = Samples;                          enterReleasePart1Stage();
96                      while (iSample < process_end) {                          break;
97                         pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;                      case event_hold_end:
98                      }                          enterDecay1Part1Stage(SampleRate);
99                      break;                          break;
100                  }                  }
101                  case stage_release: {                  break;
102                      int process_end;              case stage_sustain:
103                      if (pTransitionEvent && pTransitionEvent->Type == Event::type_cancel_release && pTransitionEvent->FragmentPos() <= Samples) {                  switch (Event) {
104                          process_end      = pTransitionEvent->FragmentPos();                      case event_stage_end: {// just refresh time
105                          pTransitionEvent = pEvents->next();                          const int intMax = (unsigned int) -1 >> 1;
106                          Stage            = (InfiniteSustain) ? stage_sustain : stage_decay2; // switch back to sustain / decay2 stage soon                          StepsLeft = intMax; // we use the highest possible value
107                      }                          break;
                     else process_end = Samples;  
                     while (iSample < process_end) {  
                         Level += Level * ReleaseCoeff;  
                         pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;  
108                      }                      }
109                      if (Level <= EG_ENVELOPE_LIMIT) Stage = stage_end;                      case event_release:
110                      break;                          enterReleasePart1Stage();
111                            break;
112                        case event_hold_end:
113                            enterDecay1Part1Stage(SampleRate);
114                            break;
115                  }                  }
116                  case stage_end: {                  break;
117                      while (iSample < Samples) {              case stage_release_part1:
118                          Level += Level * ReleaseCoeff;                  switch (Event) {
119                          pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level;                      case event_stage_end:
120                      }                          enterReleasePart2Stage();
121                      break;                          break;
122                        case event_cancel_release:
123                            if (InfiniteSustain)
124                                enterSustainStage();
125                            else
126                                enterDecay2Stage(SampleRate);
127                            break;
128                  }                  }
129              }                  break;
130                case stage_release_part2:
131                    switch (Event) {
132                        case event_stage_end:
133                            enterFadeOutStage();
134                            break;
135                        case event_cancel_release:
136                            if (InfiniteSustain)
137                                enterSustainStage();
138                            else
139                                enterDecay2Stage(SampleRate);
140                            break;
141                    }
142                    break;
143          }          }
144      }      }
145    
146      /**      void EGADSR::trigger(uint PreAttack, float AttackTime, bool HoldAttack, float Decay1Time, double Decay2Time, bool InfiniteSustain, uint SustainLevel, float ReleaseTime, float Volume, uint SampleRate) {
147       * Will be called by the voice when the key / voice was triggered.          this->SustainLevel     = SustainLevel / 1000.0;
      *  
      * @param PreAttack       - Preattack value for the envelope (0 - 1000 permille)  
      * @param AttackTime      - Attack time for the envelope (0.000 - 60.000s)  
      * @param HoldAttack      - If true, Decay1 will be postponed until the sample reached the sample loop start.  
      * @param LoopStart       - Sample position where sample loop starts (if any)  
      * @param Decay1Time      - Decay1 time of the sample amplitude EG (0.000 - 60.000s).  
      * @param Decay2Time      - Only if !InfiniteSustain: 2nd decay stage time of the sample amplitude EG (0.000 - 60.000s).  
      * @param InfiniteSustain - If true, instead of going into Decay2 phase, Decay1 level will be hold until note will be released.  
      * @param SustainLevel    - Sustain level of the sample amplitude EG (0 - 1000 permille).  
      * @param ReleaseTIme     - Release time for the envelope (0.000 - 60.000s)  
      * @param Delay           - Number of sample points triggering should be delayed.  
      */  
     void EGADSR::Trigger(uint PreAttack, double AttackTime, bool HoldAttack, long LoopStart, double Decay1Time, double Decay2Time, bool InfiniteSustain, uint SustainLevel, double ReleaseTime, uint Delay) {  
         this->TriggerDelay     = Delay;  
         this->Stage            = stage_attack;  
         this->SustainLevel     = (SustainLevel) ? (SustainLevel > EG_ENVELOPE_LIMIT) ? (float) SustainLevel / 1000.0 : EG_ENVELOPE_LIMIT : 1.0;  
148          this->InfiniteSustain  = InfiniteSustain;          this->InfiniteSustain  = InfiniteSustain;
149          this->HoldAttack       = HoldAttack;          this->HoldAttack       = HoldAttack;
         this->LoopStart        = LoopStart;  
         this->ReleasePostponed = false;  
150    
151          // calculate attack stage parameters (lin. curve)          this->Decay1Time = Decay1Time;
152          AttackStepsLeft = (long) (AttackTime * pEngine->pAudioOutputDevice->SampleRate());          this->Decay2Time = Decay2Time;
153          if (AttackStepsLeft) {  
154              Level       = (float) PreAttack / 1000.0;          invVolume = 1 / Volume;
155              AttackCoeff = (1.0 - Level) / AttackStepsLeft;          ExpOffset = (0.25 - 1 / 3.55) * invVolume;
156    
157            // calculate release stage parameters (lin+exp curve)
158            if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME;  // to avoid click sounds at the end of the sample playback
159            const float ReleaseStepsLeft = (long) (ReleaseTime * SampleRate);
160            ReleaseSlope  = 1.365 * (0 - 1) / ReleaseStepsLeft;
161            ReleaseCoeff  = ReleaseSlope * invVolume;
162            ReleaseSlope  *= 3.55;
163            ReleaseCoeff2 = exp(ReleaseSlope);
164            ReleaseCoeff3 = ExpOffset * (1 - ReleaseCoeff2);
165            ReleaseLevel2 = 0.25 * invVolume;
166    
167            enterFirstStage();
168            enterAttackStage(PreAttack, AttackTime, SampleRate);
169        }
170    
171        void EGADSR::enterAttackStage(const uint PreAttack, const float AttackTime, const uint SampleRate) {
172            Stage   = stage_attack;
173            Segment = segment_lin;
174    
175            if (AttackTime >= 1e-8) {
176                // Measurements of GSt output shows that the real attack time
177                // is about 65.5% of the value specified in the gig file.
178                // The minimum attack value used is 0.0316.
179                StepsLeft = int(0.655f * RTMath::Max(AttackTime, 0.0316f) * SampleRate);
180                Level = (float) PreAttack / 1000.0;
181                Coeff = 0.896f * (1.0f - Level) / StepsLeft; // max level is a bit lower if attack != 0
182            } else { // attack is zero - immediately jump to the next stage
183                Level = 1.029f; // a bit higher than max sustain
184                if (HoldAttack) enterAttackHoldStage();
185                else            enterDecay1Part1Stage(SampleRate);
186          }          }
187          else {      }
188              Level       = 1.0;  
189              AttackCoeff = 0.0;      void EGADSR::enterAttackHoldStage() {
190            Stage     = stage_attack_hold;
191            Segment   = segment_lin;
192            Coeff     = 0.0f; // don't rise anymore
193            const int intMax = (unsigned int) -1 >> 1;
194            StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case)
195        }
196    
197        void EGADSR::enterDecay1Part1Stage(const uint SampleRate) {
198            // The decay1 and release stage both consist of two parts,
199            // first a linear curve, f, followed by an exponential curve,
200            // g:
201            //
202            // f(x + d) = f(x) + Coeff
203            // g(x + d) = Coeff2 * g(x) + Coeff3
204            //
205            // (where d is 1/SampleRate). The transition from f to g is
206            // done when f(x) has reached Level2 = 25% of full volume.
207            StepsLeft = (int) (Decay1Time * SampleRate);
208            if (StepsLeft && Level > SustainLevel) {
209                Stage        = stage_decay1_part1;
210                Segment      = segment_lin;
211                Decay1Slope = (1.347f * SustainLevel - 1.361f) / StepsLeft;
212                Coeff        = Decay1Slope * invVolume;
213                Decay1Level2 = 0.25 * invVolume;
214                StepsLeft = int((RTMath::Max(Decay1Level2, SustainLevel) - Level) / Coeff);
215                if (StepsLeft <= 0) enterDecay1Part2Stage(SampleRate);
216            } else {
217                if (InfiniteSustain) enterSustainStage();
218                else                 enterDecay2Stage(SampleRate);
219          }          }
220        }
221    
222          // calculate decay1 stage parameters (exp. curve)      void EGADSR::enterDecay1Part2Stage(const uint SampleRate) {
223          Decay1StepsLeft = (long) (Decay1Time * pEngine->pAudioOutputDevice->SampleRate());          if (SustainLevel < Decay1Level2) {
224          Decay1Coeff     = (Decay1StepsLeft) ? exp(log(this->SustainLevel) / (double) Decay1StepsLeft) - 1.0              Stage   = stage_decay1_part2;
225                                              : 0.0;              Segment = segment_exp;
226                Decay1Slope *= 3.55;
227          // calculate decay2 stage parameters (exp. curve)              Coeff  = exp(Decay1Slope);
228          if (!InfiniteSustain) {              Offset = ExpOffset * (1 - Coeff);
229              if (Decay2Time < EG_MIN_RELEASE_TIME) Decay2Time = EG_MIN_RELEASE_TIME;              StepsLeft = int(log((SustainLevel - ExpOffset) / (Level - ExpOffset)) / Decay1Slope);
230              long Decay2Steps = (long) (Decay2Time * pEngine->pAudioOutputDevice->SampleRate());              if (StepsLeft > 0) return;
             Decay2Coeff      = (Decay2Steps) ? exp((log(EG_ENVELOPE_LIMIT) - log(this->SustainLevel)) / Decay2Steps + log(this->SustainLevel)) - this->SustainLevel  
                                             : 0.0;  
231          }          }
232            if (InfiniteSustain) enterSustainStage();
233            else                 enterDecay2Stage(SampleRate);
234        }
235    
236        void EGADSR::enterDecay2Stage(const uint SampleRate) {
237            Stage      = stage_decay2;
238            Segment    = segment_lin;
239            Decay2Time = RTMath::Max(Decay2Time, 0.05f);
240            StepsLeft  = (int) (Decay2Time * SampleRate);
241            Coeff      = (-1.03 / StepsLeft) * invVolume;
242            //FIXME: do we really have to calculate 'StepsLeft' two times?
243            StepsLeft  = int((CONFIG_EG_BOTTOM - Level) / Coeff);
244            if (StepsLeft <= 0) enterEndStage();
245        }
246    
247          // calcuate release stage parameters (exp. curve)      void EGADSR::enterSustainStage() {
248          if (ReleaseTime < EG_MIN_RELEASE_TIME) ReleaseTime = EG_MIN_RELEASE_TIME;  // to avoid click sounds at the end of the sample playback          Stage   = stage_sustain;
249          ReleaseStepsLeft = (long) (ReleaseTime * pEngine->pAudioOutputDevice->SampleRate());          Segment = segment_lin;
250          ReleaseCoeff     = exp((log(EG_ENVELOPE_LIMIT) - log(this->SustainLevel)) / ReleaseStepsLeft + log(this->SustainLevel)) - this->SustainLevel;          Coeff   = 0.0f; // don't change the envelope level in this stage
251            const int intMax = (unsigned int) -1 >> 1;
252            StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case)
253        }
254    
255        void EGADSR::enterReleasePart1Stage() {
256            Stage     = stage_release_part1;
257            Segment   = segment_lin;
258            StepsLeft = int((ReleaseLevel2 - Level) / ReleaseCoeff);
259            Coeff     = ReleaseCoeff;
260            if (StepsLeft <= 0) enterReleasePart2Stage();
261        }
262    
263          dmsg(4,("PreAttack=%d, AttackLength=%d, AttackCoeff=%f, Decay1Coeff=%f, Decay2Coeff=%f, ReleaseLength=%d, ReleaseCoeff=%f\n",      void EGADSR::enterReleasePart2Stage() {
264                  PreAttack, AttackStepsLeft, AttackCoeff, Decay1Coeff, Decay2Coeff, ReleaseStepsLeft, ReleaseCoeff));          Stage     = stage_release_part2;
265            Segment   = segment_exp;
266            StepsLeft = int(log((CONFIG_EG_BOTTOM - ExpOffset) / (Level - ExpOffset)) / ReleaseSlope);
267            Coeff     = ReleaseCoeff2;
268            Offset    = ReleaseCoeff3;
269            if (StepsLeft <= 0) enterFadeOutStage();
270      }      }
271    
272  }} // namespace LinuxSampler::gig  }} // namespace LinuxSampler::gig
Legend:
Removed from v.237  
changed lines
  Added in v.2408
  ViewVC Help
Powered by ViewVC