engines/sfz/EGADSR.cpp

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
 *   Copyright (C) 2005 - 2012 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  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the Free Software           *
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,                *
 *   MA  02110-1301  USA                                                   *
 ***************************************************************************/

#include "EGADSR.h"

#include "../../common/global_private.h"

namespace LinuxSampler { namespace sfz {

    // Modeled after output from SFZ Player 1.97 / Rapture Demo 1.0.

    void EGADSR::update(event_t Event, uint SampleRate) {
        if (atEnd(Event)) return;

        switch (Stage) {
            case stage_attack:
                switch (Event) {
                    case event_release:
                        enterReleaseStage();
                        break;
                    case event_stage_end:
                        if (HoldSteps)
                            enterAttackHoldStage();
                        else
                            enterDecayStage(SampleRate);
                        break;
                    default: ; // noop
                }
                break;
            case stage_attack_hold:
                switch (Event) {
                    case event_stage_end:
                        enterDecayStage(SampleRate);
                        break;
                    case event_release:
                        enterReleaseStage();
                        break;
                    default: ; // noop
                }
                break;
            case stage_decay:
                switch (Event) {
                    case event_release:
                        enterReleaseStage();
                        break;
                    case event_stage_end:
                        if (Level < CONFIG_EG_BOTTOM)
                            enterEndStage();
                        else
                            enterSustainStage();
                        break;
                    default: ; // noop
                }
                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;
                    }
                    case event_release:
                        enterReleaseStage();
                        break;
                    default: ; // noop
                }
                break;
            case stage_release:
                switch (Event) {
                    case event_stage_end:
                        enterFadeOutStage();
                        break;
                    case event_cancel_release:
                        enterSustainStage();
                        break;
                    default: ; // noop
                }
                break;

            case stage_fadeout:
            case stage_end:
                ; // noop
        }
    }

    void EGADSR::trigger(uint PreAttack, float AttackTime, float HoldTime, float DecayTime, uint SustainLevel, float ReleaseTime, uint SampleRate, bool LinearRelease) {
        this->SustainLevel = SustainLevel / 1000.0;
        this->HoldSteps    = int(HoldTime * SampleRate);
        this->DecayTime    = DecayTime;
        this->LinearRelease = LinearRelease;

        if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME;  // to avoid click sounds at the end of the sample playback
        this->ReleaseTime = ReleaseTime * SampleRate;
        Offset = 0;
        enterFirstStage();
        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) {
            StepsLeft = int(AttackTime * SampleRate);
            Level = (float) PreAttack / 1000.0;
            Coeff = (1.0f - Level) / StepsLeft;
        } else { // attack is zero - immediately jump to the next stage
            Level = 1.0f;
            if (HoldSteps) enterAttackHoldStage();
            else           enterDecayStage(SampleRate);
        }
    }

    void EGADSR::enterAttackHoldStage() {
        Stage     = stage_attack_hold;
        Segment   = segment_lin;
        Coeff     = 0.0f; // don't rise anymore
        StepsLeft = HoldSteps;
    }

    void EGADSR::enterDecayStage(const uint SampleRate) {
        if (LinearRelease) {
            StepsLeft = int(DecayTime * SampleRate * (Level - SustainLevel));
            if (StepsLeft > 0) {
                Stage = stage_decay;
                Segment = segment_lin;
                Coeff = -1 / (DecayTime * SampleRate);
                return;
            }
        } else {
            StepsLeft = int(DecayTime * SampleRate);
            if (StepsLeft && Level > SustainLevel) {
                Stage   = stage_decay;
                Segment = segment_exp;
                const float slope = -9.226 / StepsLeft;
                Coeff  = exp(slope);
                StepsLeft = int(log(std::max(SustainLevel, float(CONFIG_EG_BOTTOM)) / Level) / slope);
                if (StepsLeft > 0) return;
            }
        }
        Level = SustainLevel;
        enterSustainStage();
    }

    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::enterReleaseStage() {
        Stage     = stage_release;
        if (LinearRelease) {
            Segment   = segment_lin;
            StepsLeft = int(Level * ReleaseTime);
            Coeff = -1 / ReleaseTime;
        } else {
            Segment   = segment_exp;
            const float slope = -9.226 / ReleaseTime;
            StepsLeft = int(log(CONFIG_EG_BOTTOM / Level) / slope);
            Coeff     = exp(slope);
        }
        if (StepsLeft <= 0) enterFadeOutStage();
    }

}} // namespace LinuxSampler::sfz
1	/***************************************************************************
2	* *
3	* LinuxSampler - modular, streaming capable sampler *
4	* *
5	* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck *
6	* Copyright (C) 2005 - 2012 Christian Schoenebeck *
7	* *
8	* 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 *
10	* the Free Software Foundation; either version 2 of the License, or *
11	* (at your option) any later version. *
12	* *
13	* This program is distributed in the hope that it will be useful, *
14	* but WITHOUT ANY WARRANTY; without even the implied warranty of *
15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16	* GNU General Public License for more details. *
17	* *
18	* You should have received a copy of the GNU General Public License *
19	* along with this program; if not, write to the Free Software *
20	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, *
21	* MA 02110-1301 USA *
22	***************************************************************************/
23
24	#include "EGADSR.h"
25
26	#include "../../common/global_private.h"
27
28	namespace LinuxSampler { namespace sfz {
29
30	// Modeled after output from SFZ Player 1.97 / Rapture Demo 1.0.
31
32	void EGADSR::update(event_t Event, uint SampleRate) {
33	if (atEnd(Event)) return;
34
35	switch (Stage) {
36	case stage_attack:
37	switch (Event) {
38	case event_release:
39	enterReleaseStage();
40	break;
41	case event_stage_end:
42	if (HoldSteps)
43	enterAttackHoldStage();
44	else
45	enterDecayStage(SampleRate);
46	break;
47	default: ; // noop
48	}
49	break;
50	case stage_attack_hold:
51	switch (Event) {
52	case event_stage_end:
53	enterDecayStage(SampleRate);
54	break;
55	case event_release:
56	enterReleaseStage();
57	break;
58	default: ; // noop
59	}
60	break;
61	case stage_decay:
62	switch (Event) {
63	case event_release:
64	enterReleaseStage();
65	break;
66	case event_stage_end:
67	if (Level < CONFIG_EG_BOTTOM)
68	enterEndStage();
69	else
70	enterSustainStage();
71	break;
72	default: ; // noop
73	}
74	break;
75	case stage_sustain:
76	switch (Event) {
77	case event_stage_end: { // just refresh time
78	const int intMax = (unsigned int) -1 >> 1;
79	StepsLeft = intMax; // we use the highest possible value
80	break;
81	}
82	case event_release:
83	enterReleaseStage();
84	break;
85	default: ; // noop
86	}
87	break;
88	case stage_release:
89	switch (Event) {
90	case event_stage_end:
91	enterFadeOutStage();
92	break;
93	case event_cancel_release:
94	enterSustainStage();
95	break;
96	default: ; // noop
97	}
98	break;
99
100	case stage_fadeout:
101	case stage_end:
102	; // noop
103	}
104	}
105
106	void EGADSR::trigger(uint PreAttack, float AttackTime, float HoldTime, float DecayTime, uint SustainLevel, float ReleaseTime, uint SampleRate, bool LinearRelease) {
107	this->SustainLevel = SustainLevel / 1000.0;
108	this->HoldSteps = int(HoldTime * SampleRate);
109	this->DecayTime = DecayTime;
110	this->LinearRelease = LinearRelease;
111
112	if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME; // to avoid click sounds at the end of the sample playback
113	this->ReleaseTime = ReleaseTime * SampleRate;
114	Offset = 0;
115	enterFirstStage();
116	enterAttackStage(PreAttack, AttackTime, SampleRate);
117	}
118
119	void EGADSR::enterAttackStage(const uint PreAttack, const float AttackTime, const uint SampleRate) {
120	Stage = stage_attack;
121	Segment = segment_lin;
122
123	if (AttackTime >= 0.0005f) {
124	StepsLeft = int(AttackTime * SampleRate);
125	Level = (float) PreAttack / 1000.0;
126	Coeff = (1.0f - Level) / StepsLeft;
127	} else { // attack is zero - immediately jump to the next stage
128	Level = 1.0f;
129	if (HoldSteps) enterAttackHoldStage();
130	else enterDecayStage(SampleRate);
131	}
132	}
133
134	void EGADSR::enterAttackHoldStage() {
135	Stage = stage_attack_hold;
136	Segment = segment_lin;
137	Coeff = 0.0f; // don't rise anymore
138	StepsLeft = HoldSteps;
139	}
140
141	void EGADSR::enterDecayStage(const uint SampleRate) {
142	if (LinearRelease) {
143	StepsLeft = int(DecayTime * SampleRate * (Level - SustainLevel));
144	if (StepsLeft > 0) {
145	Stage = stage_decay;
146	Segment = segment_lin;
147	Coeff = -1 / (DecayTime * SampleRate);
148	return;
149	}
150	} else {
151	StepsLeft = int(DecayTime * SampleRate);
152	if (StepsLeft && Level > SustainLevel) {
153	Stage = stage_decay;
154	Segment = segment_exp;
155	const float slope = -9.226 / StepsLeft;
156	Coeff = exp(slope);
157	StepsLeft = int(log(std::max(SustainLevel, float(CONFIG_EG_BOTTOM)) / Level) / slope);
158	if (StepsLeft > 0) return;
159	}
160	}
161	Level = SustainLevel;
162	enterSustainStage();
163	}
164
165	void EGADSR::enterSustainStage() {
166	Stage = stage_sustain;
167	Segment = segment_lin;
168	Coeff = 0.0f; // don't change the envelope level in this stage
169	const int intMax = (unsigned int) -1 >> 1;
170	StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case)
171	}
172
173	void EGADSR::enterReleaseStage() {
174	Stage = stage_release;
175	if (LinearRelease) {
176	Segment = segment_lin;
177	StepsLeft = int(Level * ReleaseTime);
178	Coeff = -1 / ReleaseTime;
179	} else {
180	Segment = segment_exp;
181	const float slope = -9.226 / ReleaseTime;
182	StepsLeft = int(log(CONFIG_EG_BOTTOM / Level) / slope);
183	Coeff = exp(slope);
184	}
185	if (StepsLeft <= 0) enterFadeOutStage();
186	}
187
188	}} // namespace LinuxSampler::sfz