--- linuxsampler/trunk/src/engines/gig/EGADSR.cpp 2004/10/08 20:51:39 271 +++ linuxsampler/trunk/src/engines/gig/EGADSR.cpp 2006/01/15 18:23:11 830 @@ -3,6 +3,7 @@ * LinuxSampler - modular, streaming capable sampler * * * * Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck * + * Copyright (C) 2005 Christian Schoenebeck * * * * 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 * @@ -24,218 +25,289 @@ namespace LinuxSampler { namespace gig { - const float EGADSR::FadeOutCoeff(CalculateFadeOutCoeff()); - - float EGADSR::CalculateFadeOutCoeff() { - const float sampleRate = 44100.0; // even if the sample rate will be 192kHz it won't hurt at all - const float killSteps = EG_MIN_RELEASE_TIME * sampleRate; - return 1.0f / killSteps; + EGADSR::EGADSR() { + enterEndStage(); + Level = 0.0; + CalculateFadeOutCoeff(CONFIG_EG_MIN_RELEASE_TIME, 44100.0); // even if the sample rate will be 192kHz it won't hurt at all } - EGADSR::EGADSR(gig::Engine* pEngine, Event::destination_t ModulationDestination) { - this->pEngine = pEngine; - this->ModulationDestination = ModulationDestination; - Stage = stage_end; - Level = 0.0; + void EGADSR::CalculateFadeOutCoeff(float FadeOutTime, float SampleRate) { + const float killSteps = FadeOutTime * SampleRate / CONFIG_DEFAULT_SUBFRAGMENT_SIZE; + FadeOutCoeff = -1.0f / killSteps; } - /** - * 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 TotalSamples - 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 itTriggerEvent - event that caused triggering of the voice (only if - * the voice was triggered in the current audio - * fragment, NULL otherwise) - * @param SamplePos - current playback position - * @param CurrentPitch - current pitch value for playback - * @param itKillEvent - (optional) event which caused this voice to be killed - */ - void EGADSR::Process(uint TotalSamples, RTList* pEvents, RTList::Iterator itTriggerEvent, double SamplePos, double CurrentPitch, RTList::Iterator itKillEvent) { - // skip all events which occured before this voice was triggered - RTList::Iterator itTransitionEvent = (itTriggerEvent) ? ++itTriggerEvent : pEvents->first(); - - // if the voice was killed in this fragment we only process the time before this kill event, then switch to 'stage_fadeout' - int Samples = (itKillEvent) ? itKillEvent->FragmentPos() : (int) TotalSamples; - - int iSample = TriggerDelay; - while (iSample < TotalSamples) { - - // if the voice was killed in this fragment and we already processed the time before this kill event - if (itKillEvent && iSample >= Samples) Stage = stage_fadeout; - - switch (Stage) { - case stage_attack: { - TriggerDelay = 0; - int to_process = RTMath::Min(AttackStepsLeft, Samples - iSample); - int process_end = iSample + to_process; - AttackStepsLeft -= to_process; - while (iSample < process_end) { - Level += AttackCoeff; - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; - } - if (iSample == TotalSamples) { // postpone last transition event for the next audio fragment - RTList::Iterator itLastEvent = pEvents->last(); - if (itLastEvent) ReleasePostponed = (itLastEvent->Type == Event::type_release); - } - if (!AttackStepsLeft) Stage = (ReleasePostponed) ? stage_release : (HoldAttack) ? stage_attack_hold : stage_decay1; - break; + void EGADSR::update(event_t Event, uint SampleRate) { + if (Event == event_hold_end) HoldAttack = false; + + switch (Stage) { + case stage_attack: + switch (Event) { + case event_release: + enterReleasePart1Stage(); + break; + case event_cancel_release: + enterSustainStage(); + break; + case event_stage_end: + if (HoldAttack) + enterAttackHoldStage(); + else + enterDecay1Part1Stage(SampleRate); + break; } - case stage_attack_hold: { - if (SamplePos >= LoopStart) { - Stage = stage_decay1; + break; + case stage_attack_hold: + switch (Event) { + case event_stage_end: {// just refresh time + const int intMax = (unsigned int) -1 >> 1; + StepsLeft = intMax; // we use the highest possible value break; } - int holdstepsleft = (int) (LoopStart - SamplePos / CurrentPitch); // FIXME: just an approximation, inaccuracy grows with higher audio fragment size, sufficient for usual fragment sizes though - int to_process = RTMath::Min(holdstepsleft, Samples - iSample); - int process_end = iSample + to_process; - if (itTransitionEvent && itTransitionEvent->FragmentPos() <= process_end) { - process_end = itTransitionEvent->FragmentPos(); - Stage = (itTransitionEvent->Type == Event::type_release) ? stage_release : (InfiniteSustain) ? stage_sustain : stage_decay2; - ++itTransitionEvent; - } - else if (to_process == holdstepsleft) Stage = stage_decay1; - while (iSample < process_end) { - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; - } - break; + case event_hold_end: + enterDecay1Part1Stage(SampleRate); + break; + case event_release: + enterReleasePart1Stage(); + break; + case event_cancel_release: + if (InfiniteSustain) + enterSustainStage(); + else + enterDecay1Part1Stage(SampleRate); + break; } - case stage_decay1: { - int to_process = RTMath::Min(Samples - iSample, Decay1StepsLeft); - int process_end = iSample + to_process; - if (itTransitionEvent && itTransitionEvent->FragmentPos() <= process_end) { - process_end = itTransitionEvent->FragmentPos(); - Stage = (itTransitionEvent->Type == Event::type_release) ? stage_release : (InfiniteSustain) ? stage_sustain : stage_decay2; - ++itTransitionEvent; - } - else { - Decay1StepsLeft -= to_process; - if (!Decay1StepsLeft) Stage = (InfiniteSustain) ? stage_sustain : stage_decay2; - } - while (iSample < process_end) { - Level += Level * Decay1Coeff; - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; - } - break; + break; + case stage_decay1_part1: + switch (Event) { + case event_stage_end: + enterDecay1Part2Stage(SampleRate); + break; + case event_release: + enterReleasePart1Stage(); + break; + case event_cancel_release: + if (InfiniteSustain) + enterSustainStage(); + else + enterDecay2Stage(SampleRate); + break; } - case stage_decay2: { - int process_end; - if (itTransitionEvent && itTransitionEvent->Type == Event::type_release && itTransitionEvent->FragmentPos() <= Samples) { - process_end = itTransitionEvent->FragmentPos(); - ++itTransitionEvent; - Stage = stage_release; // switch to release stage soon - } - else process_end = Samples; - while (iSample < process_end) { - Level += Level * Decay2Coeff; - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; - } - if (Level <= EG_ENVELOPE_LIMIT) Stage = stage_fadeout; - break; + break; + case stage_decay1_part2: + switch (Event) { + case event_release: + enterReleasePart1Stage(); + break; + case event_stage_end: // fall through + case event_cancel_release: + if (Level < CONFIG_EG_BOTTOM) + enterEndStage(); + else if (InfiniteSustain) + enterSustainStage(); + else + enterDecay2Stage(SampleRate); + break; } - case stage_sustain: { - int process_end; - if (itTransitionEvent && itTransitionEvent->Type == Event::type_release && itTransitionEvent->FragmentPos() <= Samples) { - process_end = itTransitionEvent->FragmentPos(); - ++itTransitionEvent; - Stage = stage_release; // switch to release stage soon - } - else process_end = Samples; - while (iSample < process_end) { - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; - } - break; + break; + case stage_decay2: + switch (Event) { + case event_stage_end: + enterFadeOutStage(); + break; + case event_release: + enterReleasePart1Stage(); + break; + case event_hold_end: + enterDecay1Part1Stage(SampleRate); + break; } - case stage_release: { - int process_end; - if (itTransitionEvent && itTransitionEvent->Type == Event::type_cancel_release && itTransitionEvent->FragmentPos() <= Samples) { - process_end = itTransitionEvent->FragmentPos(); - ++itTransitionEvent; - Stage = (InfiniteSustain) ? stage_sustain : stage_decay2; // switch back to sustain / decay2 stage soon - } - else process_end = Samples; - while (iSample < process_end) { - Level += Level * ReleaseCoeff; - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; + break; + case stage_sustain: + switch (Event) { + case event_stage_end: {// just refresh time + const int intMax = (unsigned int) -1 >> 1; + StepsLeft = intMax; // we use the highest possible value + break; } - if (Level <= EG_ENVELOPE_LIMIT) Stage = stage_fadeout; - break; + case event_release: + enterReleasePart1Stage(); + break; + case event_hold_end: + enterDecay1Part1Stage(SampleRate); + break; } - case stage_fadeout: { - int to_process = RTMath::Min(int(Level / (-FadeOutCoeff)), TotalSamples - iSample); - int process_end = iSample + to_process; - while (iSample < process_end) { - Level += FadeOutCoeff; - pEngine->pSynthesisParameters[ModulationDestination][iSample++] *= Level; - } - if (Level <= FadeOutCoeff) Stage = stage_end; - } //Fall through here instead of breaking otherwise we can get back into stage_fadeout and loop forever! - case stage_end: { - while (iSample < TotalSamples) { - pEngine->pSynthesisParameters[ModulationDestination][iSample++] = 0.0f; - } - break; + break; + case stage_release_part1: + switch (Event) { + case event_stage_end: + enterReleasePart2Stage(); + break; + case event_cancel_release: + if (InfiniteSustain) + enterSustainStage(); + else + enterDecay2Stage(SampleRate); + break; + } + break; + case stage_release_part2: + switch (Event) { + case event_stage_end: + enterFadeOutStage(); + break; + case event_cancel_release: + if (InfiniteSustain) + enterSustainStage(); + else + enterDecay2Stage(SampleRate); + break; + } + break; + case stage_fadeout: + switch (Event) { + case event_stage_end: + enterEndStage(); + break; } - } + break; } } - /** - * Will be called by the voice when the key / voice was triggered. - * - * @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; + void EGADSR::trigger(uint PreAttack, float AttackTime, bool HoldAttack, float Decay1Time, double Decay2Time, bool InfiniteSustain, uint SustainLevel, float ReleaseTime, float Volume, uint SampleRate) { + this->SustainLevel = SustainLevel / 1000.0; this->InfiniteSustain = InfiniteSustain; this->HoldAttack = HoldAttack; - this->LoopStart = LoopStart; - this->ReleasePostponed = false; - // calculate attack stage parameters (lin. curve) - AttackStepsLeft = (long) (AttackTime * pEngine->pAudioOutputDevice->SampleRate()); - if (AttackStepsLeft) { - Level = (float) PreAttack / 1000.0; - AttackCoeff = (1.0 - Level) / AttackStepsLeft; + this->Decay1Time = Decay1Time; + this->Decay2Time = Decay2Time; + + invVolume = 1 / Volume; + ExpOffset = (0.25 - 1 / 3.55) * invVolume; + + // calculate release stage parameters (lin+exp curve) + if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME; // to avoid click sounds at the end of the sample playback + const float ReleaseStepsLeft = (long) (ReleaseTime * SampleRate); + ReleaseSlope = 1.365 * (0 - 1) / ReleaseStepsLeft; + ReleaseCoeff = ReleaseSlope * invVolume; + ReleaseSlope *= 3.55; + ReleaseCoeff2 = exp(ReleaseSlope); + ReleaseCoeff3 = ExpOffset * (1 - ReleaseCoeff2); + ReleaseLevel2 = 0.25 * invVolume; + + enterAttackStage(PreAttack, AttackTime, SampleRate); + } + + void EGADSR::enterAttackStage(const uint PreAttack, const float AttackTime, const uint SampleRate) { + Stage = stage_attack; + Segment = segment_lin; + + if (AttackTime >= 0.0005f) { + // Measurements of GSt output shows that the real attack time + // is about 65.5% of the value specified in the gig file. + // The minimum attack value used is 0.032. + StepsLeft = int(0.655f * RTMath::Max(AttackTime, 0.032f) * SampleRate); + Level = (float) PreAttack / 1000.0; + Coeff = 0.896f * (1.0f - Level) / StepsLeft; // max level is a bit lower if attack != 0 + } else { // attack is zero - immediately jump to the next stage + Level = 1.0; + if (HoldAttack) enterAttackHoldStage(); + else enterDecay1Part1Stage(SampleRate); } - else { - Level = 1.0; - AttackCoeff = 0.0; + } + + void EGADSR::enterAttackHoldStage() { + Stage = stage_attack_hold; + Segment = segment_lin; + Coeff = 0.0f; // don't rise anymore + const int intMax = (unsigned int) -1 >> 1; + StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case) + } + + void EGADSR::enterDecay1Part1Stage(const uint SampleRate) { + // The decay1 and release stage both consist of two parts, + // first a linear curve, f, followed by an exponential curve, + // g: + // + // f(x + d) = f(x) + Coeff + // g(x + d) = Coeff2 * g(x) + Coeff3 + // + // (where d is 1/SampleRate). The transition from f to g is + // done when f(x) has reached Level2 = 25% of full volume. + StepsLeft = (int) (Decay1Time * SampleRate); + if (StepsLeft && SustainLevel < 1.0 && Level > SustainLevel) { + Stage = stage_decay1_part1; + Segment = segment_lin; + Decay1Slope = 1.365 * (SustainLevel - 1.0) / StepsLeft; + Coeff = Decay1Slope * invVolume; + Decay1Level2 = 0.25 * invVolume; + if (Level < Decay1Level2) enterDecay1Part2Stage(SampleRate); + else StepsLeft = int((RTMath::Max(Decay1Level2, SustainLevel) - Level) / Coeff); + } else { + if (InfiniteSustain) enterSustainStage(); + else enterDecay2Stage(SampleRate); } + } - // calculate decay1 stage parameters (exp. curve) - Decay1StepsLeft = (long) (Decay1Time * pEngine->pAudioOutputDevice->SampleRate()); - Decay1Coeff = (Decay1StepsLeft) ? exp(log(this->SustainLevel) / (double) Decay1StepsLeft) - 1.0 - : 0.0; - - // calculate decay2 stage parameters (exp. curve) - if (!InfiniteSustain) { - if (Decay2Time < EG_MIN_RELEASE_TIME) Decay2Time = EG_MIN_RELEASE_TIME; - long Decay2Steps = (long) (Decay2Time * pEngine->pAudioOutputDevice->SampleRate()); - Decay2Coeff = (Decay2Steps) ? exp((log(EG_ENVELOPE_LIMIT) - log(this->SustainLevel)) / Decay2Steps + log(this->SustainLevel)) - this->SustainLevel - : 0.0; + void EGADSR::enterDecay1Part2Stage(const uint SampleRate) { + if (SustainLevel < Decay1Level2) { + Stage = stage_decay1_part2; + Segment = segment_exp; + Decay1Slope *= 3.55; + Coeff = exp(Decay1Slope); + Offset = ExpOffset * (1 - Coeff); + StepsLeft = int(log((SustainLevel - ExpOffset) / (Level - ExpOffset)) / Decay1Slope); + } else { + if (InfiniteSustain) enterSustainStage(); + else enterDecay2Stage(SampleRate); } + } + + void EGADSR::enterDecay2Stage(const uint SampleRate) { + Stage = stage_decay2; + Segment = segment_lin; + Decay2Time = RTMath::Max(Decay2Time, CONFIG_EG_MIN_RELEASE_TIME); + StepsLeft = (int) (Decay2Time * SampleRate); + Coeff = (-1.03 / StepsLeft) * invVolume; + //FIXME: do we really have to calculate 'StepsLeft' two times? + StepsLeft = int((CONFIG_EG_BOTTOM - Level) / Coeff); + if (StepsLeft == 0) enterEndStage(); + } - // calculate release stage parameters (exp. curve) - if (ReleaseTime < EG_MIN_RELEASE_TIME) ReleaseTime = EG_MIN_RELEASE_TIME; // to avoid click sounds at the end of the sample playback - ReleaseStepsLeft = (long) (ReleaseTime * pEngine->pAudioOutputDevice->SampleRate()); - ReleaseCoeff = exp((log(EG_ENVELOPE_LIMIT) - log(this->SustainLevel)) / ReleaseStepsLeft + log(this->SustainLevel)) - this->SustainLevel; + void EGADSR::enterSustainStage() { + Stage = stage_sustain; + Segment = segment_lin; + Coeff = 0.0f; // don't change the envelope level in this stage + const int intMax = (unsigned int) -1 >> 1; + StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case) + } + + void EGADSR::enterReleasePart1Stage() { + Stage = stage_release_part1; + Segment = segment_lin; + StepsLeft = int((ReleaseLevel2 - Level) / ReleaseCoeff); + Coeff = ReleaseCoeff; + } + + void EGADSR::enterReleasePart2Stage() { + Stage = stage_release_part2; + Segment = segment_exp; + StepsLeft = int(log((CONFIG_EG_BOTTOM - ExpOffset) / (Level - ExpOffset)) / ReleaseSlope); + Coeff = ReleaseCoeff2; + Offset = ReleaseCoeff3; + } + + void EGADSR::enterFadeOutStage() { + Stage = stage_fadeout; + Segment = segment_lin; + StepsLeft = int(Level / (-FadeOutCoeff)); + Coeff = FadeOutCoeff; + if (StepsLeft == 0) enterEndStage(); + } - dmsg(4,("PreAttack=%d, AttackLength=%d, AttackCoeff=%f, Decay1Coeff=%f, Decay2Coeff=%f, ReleaseLength=%d, ReleaseCoeff=%f\n", - PreAttack, AttackStepsLeft, AttackCoeff, Decay1Coeff, Decay2Coeff, ReleaseStepsLeft, ReleaseCoeff)); + void EGADSR::enterEndStage() { + Stage = stage_end; + Segment = segment_end; + Level = 0; } }} // namespace LinuxSampler::gig