engines/common/LFOPulse.h

/***************************************************************************
 *                                                                         *
 *   Copyright (C) 2005 Christian Schoenebeck                              *
 *   Copyright (C) 2011 Christian Schoenebeck and Grigor Iliev             *
 *                                                                         *
 *   This library 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 library 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 library; if not, write to the Free Software           *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 ***************************************************************************/

#ifndef __LS_PULSELFO_H__
#define __LS_PULSELFO_H__

#include "LFOBase.h"

namespace LinuxSampler {

    /** @brief Pulse LFO (int math implementation)
     *
     * This is a pulse Low Frequency Oscillator which uses pure integer
     * math (without branches) to synthesize the pulse wave.
     */
    template<range_type_t RANGE, int WIDTH /* in permilles */>
    class PulseLFO : public LFOBase<RANGE> {
        public:

            /**
             * Constructor
             *
             * @param Max - maximum value of the output levels
             */
            PulseLFO(float Max) : LFOBase<RANGE>::LFOBase(Max) {
            }

            /**
             * Calculates exactly one sample point of the LFO wave.
             *
             * @returns next LFO level
             */
            inline float render() {
                uiLevel += c;
                if (RANGE == range_unsigned)
                    return uiLevel <= width ? normalizer : 0;
                else /* signed range */
                    return uiLevel <= width ? normalizer : -normalizer;
            }

            /**
             * Update LFO depth with a new external controller value.
             *
             * @param ExtControlValue - new external controller value
             */
            inline void updateByMIDICtrlValue(const uint16_t& ExtControlValue) {
                this->ExtControlValue = ExtControlValue;

                const float max = (this->InternalDepth + ExtControlValue * this->ExtControlDepthCoeff) * this->ScriptDepthFactor;
                normalizer = max;
            }

            /**
             * Will be called by the voice when the key / voice was triggered.
             *
             * @param Frequency       - frequency of the oscillator in Hz
             * @param InternalDepth   - firm, internal oscillator amplitude
             * @param ExtControlDepth - defines how strong the external MIDI
             *                          controller has influence on the
             *                          oscillator amplitude
             * @param FlipPhase       - inverts the oscillator wave against
             *                          a horizontal axis
             * @param SampleRate      - current sample rate of the engines
             *                          audio output signal
             * @param PulseWidth      - the pulse width in percents
             */
            void trigger(float Frequency, uint16_t InternalDepth, uint16_t ExtControlDepth, float PulseWidth, unsigned int SampleRate) {
                this->Frequency            = Frequency;
                this->InternalDepth        = (InternalDepth / 1200.0f) * this->Max;
                this->ExtControlDepthCoeff = (((float) ExtControlDepth / 1200.0f) / 127.0f) * this->Max;
                this->ScriptFrequencyFactor = this->ScriptDepthFactor = 1.f; // reset for new voice
                this->pFinalDepth = NULL;
                this->pFinalFrequency = NULL;

                const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
                const float freq = Frequency * this->ScriptFrequencyFactor;
                const float r = freq / (float) SampleRate; // frequency alteration quotient
                c = (int) (intLimit * r);
                width = (PulseWidth / 100.0) * intLimit;

                uiLevel = 0;
            }
            
            virtual void trigger(float Frequency, start_level_t StartLevel, uint16_t InternalDepth, uint16_t ExtControlDepth, bool FlipPhase, unsigned int SampleRate) {
                trigger(Frequency, InternalDepth, ExtControlDepth, WIDTH / 10.0f, SampleRate);
            }
            
            /**
             * Should be invoked after the LFO is triggered.
             * @param phase From 0 to 360 degrees.
             */
            void setPhase(float phase) {
                if (phase < 0) phase = 0;
                if (phase > 360) phase = 360;
                phase /= 360.0f;
                const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
                uiLevel = intLimit * phase;
            }
            
            void setFrequency(float Frequency, unsigned int SampleRate) {
                this->Frequency = Frequency;
                const float freq = Frequency * this->ScriptFrequencyFactor;
                const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
                float r = freq / (float) SampleRate; // frequency alteration quotient
                c = (int) (intLimit * r);
            }

            void setScriptDepthFactor(float factor, bool isFinal) {
                this->ScriptDepthFactor = factor;
                // set or reset this script depth parameter to be the sole
                // source for the LFO depth
                if (isFinal && !this->pFinalDepth)
                    this->pFinalDepth = &this->ScriptDepthFactor;
                else if (!isFinal && this->pFinalDepth == &this->ScriptDepthFactor)
                    this->pFinalDepth = NULL;
                // recalculate upon new depth
                updateByMIDICtrlValue(this->ExtControlValue);
            }

            void setScriptFrequencyFactor(float factor, unsigned int SampleRate) {
                this->ScriptFrequencyFactor = factor;
                // in case script frequency was set as "final" value before,
                // reset it so that all sources are processed from now on
                if (this->pFinalFrequency == &this->ScriptFrequencyFactor)
                    this->pFinalFrequency = NULL;
                // recalculate upon new frequency
                setFrequency(this->Frequency, SampleRate);
            }

            void setScriptFrequencyFinal(float hz, unsigned int SampleRate) {
                this->ScriptFrequencyFactor = hz;
                // assign script's given frequency as sole source for the LFO
                // frequency, thus ignore all other sources
                if (!this->pFinalFrequency)
                    this->pFinalFrequency = &this->ScriptFrequencyFactor;
                // recalculate upon new frequency
                setFrequency(this->Frequency, SampleRate);
            }

        protected:
            unsigned int uiLevel;
            unsigned int width;
            int   c;
            float normalizer;
    };
    
    template<range_type_t RANGE>
    class SquareLFO : public PulseLFO<RANGE, 500> {
        public:
            SquareLFO(float Max) : PulseLFO<RANGE, 500>::PulseLFO(Max) { }
    };

} // namespace LinuxSampler

#endif // __LS_PULSELFO_H__
1	iliev	2223	/***************************************************************************
2			* *
3			* Copyright (C) 2005 Christian Schoenebeck *
4			* Copyright (C) 2011 Christian Schoenebeck and Grigor Iliev *
5			* *
6			* This library is free software; you can redistribute it and/or modify *
7			* it under the terms of the GNU General Public License as published by *
8			* the Free Software Foundation; either version 2 of the License, or *
9			* (at your option) any later version. *
10			* *
11			* This library is distributed in the hope that it will be useful, *
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of *
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
14			* GNU General Public License for more details. *
15			* *
16			* You should have received a copy of the GNU General Public License *
17			* along with this library; if not, write to the Free Software *
18			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
19			* MA 02111-1307 USA *
20			***************************************************************************/
21
22			#ifndef __LS_PULSELFO_H__
23			#define __LS_PULSELFO_H__
24
25			#include "LFOBase.h"
26
27			namespace LinuxSampler {
28
29			/** @brief Pulse LFO (int math implementation)
30			*
31			* This is a pulse Low Frequency Oscillator which uses pure integer
32			* math (without branches) to synthesize the pulse wave.
33			*/
34			template<range_type_t RANGE, int WIDTH /* in permilles */>
35			class PulseLFO : public LFOBase<RANGE> {
36			public:
37
38			/**
39			* Constructor
40			*
41			* @param Max - maximum value of the output levels
42			*/
43			PulseLFO(float Max) : LFOBase<RANGE>::LFOBase(Max) {
44			}
45
46			/**
47			* Calculates exactly one sample point of the LFO wave.
48			*
49			* @returns next LFO level
50			*/
51			inline float render() {
52			uiLevel += c;
53			if (RANGE == range_unsigned)
54			return uiLevel <= width ? normalizer : 0;
55			else /* signed range */
56			return uiLevel <= width ? normalizer : -normalizer;
57			}
58
59			/**
60			* Update LFO depth with a new external controller value.
61			*
62			* @param ExtControlValue - new external controller value
63			*/
64	schoenebeck	3118	inline void updateByMIDICtrlValue(const uint16_t& ExtControlValue) {
65			this->ExtControlValue = ExtControlValue;
66
67			const float max = (this->InternalDepth + ExtControlValue * this->ExtControlDepthCoeff) * this->ScriptDepthFactor;
68	iliev	2223	normalizer = max;
69			}
70
71			/**
72			* Will be called by the voice when the key / voice was triggered.
73			*
74			* @param Frequency - frequency of the oscillator in Hz
75			* @param InternalDepth - firm, internal oscillator amplitude
76			* @param ExtControlDepth - defines how strong the external MIDI
77			* controller has influence on the
78			* oscillator amplitude
79			* @param FlipPhase - inverts the oscillator wave against
80			* a horizontal axis
81			* @param SampleRate - current sample rate of the engines
82			* audio output signal
83			* @param PulseWidth - the pulse width in percents
84			*/
85			void trigger(float Frequency, uint16_t InternalDepth, uint16_t ExtControlDepth, float PulseWidth, unsigned int SampleRate) {
86	schoenebeck	3118	this->Frequency = Frequency;
87	iliev	2223	this->InternalDepth = (InternalDepth / 1200.0f) * this->Max;
88			this->ExtControlDepthCoeff = (((float) ExtControlDepth / 1200.0f) / 127.0f) * this->Max;
89	schoenebeck	3118	this->ScriptFrequencyFactor = this->ScriptDepthFactor = 1.f; // reset for new voice
90	schoenebeck	3561	this->pFinalDepth = NULL;
91			this->pFinalFrequency = NULL;
92	iliev	2223
93			const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
94	schoenebeck	3118	const float freq = Frequency * this->ScriptFrequencyFactor;
95			const float r = freq / (float) SampleRate; // frequency alteration quotient
96	iliev	2223	c = (int) (intLimit * r);
97			width = (PulseWidth / 100.0) * intLimit;
98
99			uiLevel = 0;
100			}
101
102			virtual void trigger(float Frequency, start_level_t StartLevel, uint16_t InternalDepth, uint16_t ExtControlDepth, bool FlipPhase, unsigned int SampleRate) {
103			trigger(Frequency, InternalDepth, ExtControlDepth, WIDTH / 10.0f, SampleRate);
104			}
105	iliev	2225
106			/**
107			* Should be invoked after the LFO is triggered.
108			* @param phase From 0 to 360 degrees.
109			*/
110			void setPhase(float phase) {
111			if (phase < 0) phase = 0;
112			if (phase > 360) phase = 360;
113			phase /= 360.0f;
114			const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
115			uiLevel = intLimit * phase;
116			}
117	iliev	2227
118			void setFrequency(float Frequency, unsigned int SampleRate) {
119	schoenebeck	3118	this->Frequency = Frequency;
120			const float freq = Frequency * this->ScriptFrequencyFactor;
121	iliev	2227	const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
122	schoenebeck	3118	float r = freq / (float) SampleRate; // frequency alteration quotient
123	iliev	2227	c = (int) (intLimit * r);
124			}
125	iliev	2223
126	schoenebeck	3561	void setScriptDepthFactor(float factor, bool isFinal) {
127	schoenebeck	3118	this->ScriptDepthFactor = factor;
128	schoenebeck	3561	// set or reset this script depth parameter to be the sole
129			// source for the LFO depth
130			if (isFinal && !this->pFinalDepth)
131			this->pFinalDepth = &this->ScriptDepthFactor;
132			else if (!isFinal && this->pFinalDepth == &this->ScriptDepthFactor)
133			this->pFinalDepth = NULL;
134			// recalculate upon new depth
135	schoenebeck	3118	updateByMIDICtrlValue(this->ExtControlValue);
136			}
137
138			void setScriptFrequencyFactor(float factor, unsigned int SampleRate) {
139			this->ScriptFrequencyFactor = factor;
140	schoenebeck	3561	// in case script frequency was set as "final" value before,
141			// reset it so that all sources are processed from now on
142			if (this->pFinalFrequency == &this->ScriptFrequencyFactor)
143			this->pFinalFrequency = NULL;
144			// recalculate upon new frequency
145	schoenebeck	3118	setFrequency(this->Frequency, SampleRate);
146			}
147
148	schoenebeck	3561	void setScriptFrequencyFinal(float hz, unsigned int SampleRate) {
149			this->ScriptFrequencyFactor = hz;
150			// assign script's given frequency as sole source for the LFO
151			// frequency, thus ignore all other sources
152			if (!this->pFinalFrequency)
153			this->pFinalFrequency = &this->ScriptFrequencyFactor;
154			// recalculate upon new frequency
155			setFrequency(this->Frequency, SampleRate);
156			}
157
158	iliev	2223	protected:
159			unsigned int uiLevel;
160			unsigned int width;
161			int c;
162			float normalizer;
163			};
164
165			template<range_type_t RANGE>
166			class SquareLFO : public PulseLFO<RANGE, 500> {
167			public:
168			SquareLFO(float Max) : PulseLFO<RANGE, 500>::PulseLFO(Max) { }
169			};
170
171			} // namespace LinuxSampler
172
173			#endif // __LS_PULSELFO_H__