engines/sfz/EGADSR.cpp

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
 *   Copyright (C) 2005 - 2011 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.

    // TODO: implement hold stage correctly

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

    // TODO: HoldAttack should be HoldTime and float

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

        if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME;  // to avoid click sounds at the end of the sample playback
        ReleaseSlope = -9.226 / (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 (HoldAttack) enterAttackHoldStage();
            else            enterDecayStage(SampleRate);
        }
    }

    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::enterDecayStage(const uint SampleRate) {
        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;

            enterSustainStage();
        } else {
            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;
        Segment   = segment_exp;
        StepsLeft = int(log(CONFIG_EG_BOTTOM / Level) / ReleaseSlope);
        Coeff     = exp(ReleaseSlope);
        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 - 2011 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	// TODO: implement hold stage correctly
33
34	void EGADSR::update(event_t Event, uint SampleRate) {
35	if (atEnd(Event)) return;
36
37	switch (Stage) {
38	case stage_attack:
39	switch (Event) {
40	case event_release:
41	enterReleaseStage();
42	break;
43	case event_stage_end:
44	if (HoldAttack)
45	enterAttackHoldStage();
46	else
47	enterDecayStage(SampleRate);
48	break;
49	}
50	break;
51	case stage_attack_hold:
52	switch (Event) {
53	case event_stage_end:
54	enterDecayStage(SampleRate);
55	break;
56	case event_release:
57	enterReleaseStage();
58	break;
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	}
73	break;
74	case stage_sustain:
75	switch (Event) {
76	case event_stage_end: { // just refresh time
77	const int intMax = (unsigned int) -1 >> 1;
78	StepsLeft = intMax; // we use the highest possible value
79	break;
80	}
81	case event_release:
82	enterReleaseStage();
83	break;
84	}
85	break;
86	case stage_release:
87	switch (Event) {
88	case event_stage_end:
89	enterFadeOutStage();
90	break;
91	case event_cancel_release:
92	enterSustainStage();
93	break;
94	}
95	break;
96	}
97	}
98
99	// TODO: HoldAttack should be HoldTime and float
100
101	void EGADSR::trigger(uint PreAttack, float AttackTime, bool HoldAttack, float DecayTime, uint SustainLevel, float ReleaseTime, uint SampleRate) {
102	this->SustainLevel = SustainLevel / 1000.0;
103	this->HoldAttack = HoldAttack;
104	this->DecayTime = DecayTime;
105
106	if (ReleaseTime < CONFIG_EG_MIN_RELEASE_TIME) ReleaseTime = CONFIG_EG_MIN_RELEASE_TIME; // to avoid click sounds at the end of the sample playback
107	ReleaseSlope = -9.226 / (ReleaseTime * SampleRate);
108	Offset = 0;
109	enterFirstStage();
110	enterAttackStage(PreAttack, AttackTime, SampleRate);
111	}
112
113	void EGADSR::enterAttackStage(const uint PreAttack, const float AttackTime, const uint SampleRate) {
114	Stage = stage_attack;
115	Segment = segment_lin;
116
117	if (AttackTime >= 0.0005f) {
118	StepsLeft = int(AttackTime * SampleRate);
119	Level = (float) PreAttack / 1000.0;
120	Coeff = (1.0f - Level) / StepsLeft;
121	} else { // attack is zero - immediately jump to the next stage
122	Level = 1.0f;
123	if (HoldAttack) enterAttackHoldStage();
124	else enterDecayStage(SampleRate);
125	}
126	}
127
128	void EGADSR::enterAttackHoldStage() {
129	Stage = stage_attack_hold;
130	Segment = segment_lin;
131	Coeff = 0.0f; // don't rise anymore
132	const int intMax = (unsigned int) -1 >> 1;
133	StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case)
134	}
135
136	void EGADSR::enterDecayStage(const uint SampleRate) {
137	StepsLeft = (int) (DecayTime * SampleRate);
138	if (StepsLeft && Level > SustainLevel) {
139	Stage = stage_decay;
140	Segment = segment_exp;
141	const float slope = -9.226 / StepsLeft;
142	Coeff = exp(slope);
143	StepsLeft = int(log(std::max(SustainLevel, float(CONFIG_EG_BOTTOM)) / Level) / slope);
144	if (StepsLeft > 0) return;
145
146	enterSustainStage();
147	} else {
148	enterSustainStage();
149	}
150	}
151
152	void EGADSR::enterSustainStage() {
153	Stage = stage_sustain;
154	Segment = segment_lin;
155	Coeff = 0.0f; // don't change the envelope level in this stage
156	const int intMax = (unsigned int) -1 >> 1;
157	StepsLeft = intMax; // we use the highest value possible (we refresh StepsLeft in update() in case)
158	}
159
160	void EGADSR::enterReleaseStage() {
161	Stage = stage_release;
162	Segment = segment_exp;
163	StepsLeft = int(log(CONFIG_EG_BOTTOM / Level) / ReleaseSlope);
164	Coeff = exp(ReleaseSlope);
165	if (StepsLeft <= 0) enterFadeOutStage();
166	}
167
168	}} // namespace LinuxSampler::sfz