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/*************************************************************************** |
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* * |
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* LinuxSampler - modular, streaming capable sampler * |
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* * |
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* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck * |
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* Copyright (C) 2005 - 2012 Christian Schoenebeck * |
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* * |
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* This program is free software; you can redistribute it and/or modify * |
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* it under the terms of the GNU General Public License as published by * |
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* the Free Software Foundation; either version 2 of the License, or * |
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* (at your option) any later version. * |
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* * |
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* This program is distributed in the hope that it will be useful, * |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of * |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
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* GNU General Public License for more details. * |
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* * |
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* You should have received a copy of the GNU General Public License * |
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* along with this program; if not, write to the Free Software * |
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, * |
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* MA 02110-1301 USA * |
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***************************************************************************/ |
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|
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#include "EGADSR.h" |
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|
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#include "../../common/global_private.h" |
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|
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namespace LinuxSampler { namespace sfz { |
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|
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// Modeled after output from SFZ Player 1.97 / Rapture Demo 1.0. |
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|
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void EGADSR::update(event_t Event, uint SampleRate) { |
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if (atEnd(Event)) return; |
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|
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switch (Stage) { |
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case stage_attack: |
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switch (Event) { |
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case event_release: |
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enterReleaseStage(); |
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break; |
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case event_stage_end: |
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if (HoldSteps) |
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enterAttackHoldStage(); |
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else |
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enterDecayStage(SampleRate); |
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break; |
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} |
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break; |
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case stage_attack_hold: |
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switch (Event) { |
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case event_stage_end: |
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enterDecayStage(SampleRate); |
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break; |
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case event_release: |
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enterReleaseStage(); |
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break; |
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} |
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break; |
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case stage_decay: |
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switch (Event) { |
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case event_release: |
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enterReleaseStage(); |
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break; |
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case event_stage_end: |
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if (Level < CONFIG_EG_BOTTOM) |
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enterEndStage(); |
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else |
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enterSustainStage(); |
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break; |
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} |
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break; |
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case stage_sustain: |
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switch (Event) { |
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case event_stage_end: { // just refresh time |
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const int intMax = (unsigned int) -1 >> 1; |
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StepsLeft = intMax; // we use the highest possible value |
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break; |
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} |
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case event_release: |
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enterReleaseStage(); |
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break; |
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} |
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break; |
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case stage_release: |
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switch (Event) { |
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case event_stage_end: |
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enterFadeOutStage(); |
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break; |
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case event_cancel_release: |
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enterSustainStage(); |
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break; |
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} |
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break; |
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} |
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} |
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|
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void EGADSR::trigger(uint PreAttack, float AttackTime, float HoldTime, float DecayTime, uint SustainLevel, float ReleaseTime, uint SampleRate, bool LinearRelease) { |
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this->SustainLevel = SustainLevel / 1000.0; |
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this->HoldSteps = int(HoldTime * SampleRate); |
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this->DecayTime = DecayTime; |
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this->LinearRelease = LinearRelease; |
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|
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if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME; // to avoid click sounds at the end of the sample playback |
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this->ReleaseTime = ReleaseTime * SampleRate; |
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Offset = 0; |
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enterFirstStage(); |
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enterAttackStage(PreAttack, AttackTime, SampleRate); |
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} |
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|
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void EGADSR::enterAttackStage(const uint PreAttack, const float AttackTime, const uint SampleRate) { |
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Stage = stage_attack; |
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Segment = segment_lin; |
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|
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if (AttackTime >= 0.0005f) { |
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StepsLeft = int(AttackTime * SampleRate); |
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Level = (float) PreAttack / 1000.0; |
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Coeff = (1.0f - Level) / StepsLeft; |
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} else { // attack is zero - immediately jump to the next stage |
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Level = 1.0f; |
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if (HoldSteps) enterAttackHoldStage(); |
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else enterDecayStage(SampleRate); |
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} |
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} |
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|
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void EGADSR::enterAttackHoldStage() { |
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Stage = stage_attack_hold; |
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Segment = segment_lin; |
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Coeff = 0.0f; // don't rise anymore |
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StepsLeft = HoldSteps; |
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} |
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|
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void EGADSR::enterDecayStage(const uint SampleRate) { |
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if (LinearRelease) { |
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StepsLeft = int(DecayTime * SampleRate * (Level - SustainLevel)); |
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if (StepsLeft > 0) { |
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Stage = stage_decay; |
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Segment = segment_lin; |
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Coeff = -1 / (DecayTime * SampleRate); |
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return; |
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} |
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} else { |
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StepsLeft = int(DecayTime * SampleRate); |
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if (StepsLeft && Level > SustainLevel) { |
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Stage = stage_decay; |
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Segment = segment_exp; |
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const float slope = -9.226 / StepsLeft; |
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Coeff = exp(slope); |
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StepsLeft = int(log(std::max(SustainLevel, float(CONFIG_EG_BOTTOM)) / Level) / slope); |
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if (StepsLeft > 0) return; |
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} |
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} |
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Level = SustainLevel; |
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enterSustainStage(); |
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} |
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|
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void EGADSR::enterSustainStage() { |
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Stage = stage_sustain; |
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Segment = segment_lin; |
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Coeff = 0.0f; // don't change the envelope level in this stage |
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const int intMax = (unsigned int) -1 >> 1; |
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StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case) |
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} |
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|
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void EGADSR::enterReleaseStage() { |
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Stage = stage_release; |
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if (LinearRelease) { |
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Segment = segment_lin; |
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StepsLeft = int(Level * ReleaseTime); |
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Coeff = -1 / ReleaseTime; |
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} else { |
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Segment = segment_exp; |
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const float slope = -9.226 / ReleaseTime; |
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StepsLeft = int(log(CONFIG_EG_BOTTOM / Level) / slope); |
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Coeff = exp(slope); |
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} |
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if (StepsLeft <= 0) enterFadeOutStage(); |
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} |
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|
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}} // namespace LinuxSampler::sfz |