engines/common/LFOSawIntMathNew.h

/*
 * Copyright (c) 2019 Christian Schoenebeck
 *
 * http://www.linuxsampler.org
 *
 * This file is part of LinuxSampler and released under the same terms.
 * See README file for details.
 */

#ifndef LS_LFOSAWINTMATHNEW_H
#define LS_LFOSAWINTMATHNEW_H

#include <stdlib.h>
#include "LFOBase.h"

namespace LinuxSampler {

    /** @brief Saw LFO (int math implementation)
     *
     * This is a Saw Low Frequency Oscillator which uses pure integer
     * math (without branches) to synthesize the saw wave.
     */
    template<LFO::range_type_t RANGE>
    class LFOSawIntMathNew : public LFOBase<RANGE> {
        public:
            /**
             * Constructor
             *
             * @param Max - maximum value of the output levels
             */
            LFOSawIntMathNew(float Max) : LFOBase<RANGE>::LFOBase(Max) {
                //NOTE: DO NOT add any custom initialization here, since it would break LFOCluster construction !
            }

            /**
             * Calculates exactly one sample point of the LFO wave.
             *
             * @returns next LFO level
             */
            inline float render() {
                this->slope += this->c;
                if (RANGE == LFO::range_unsigned)
                    return this->denormalizer * float(this->slope);
                else // signed range
                    return this->denormalizer * float(int(this->slope) + this->offset);
            }

            /**
             * 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 unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
                const float max = (this->InternalDepth + ExtControlValue * this->ExtControlDepthCoeff) * this->ScriptDepthFactor;
                if (RANGE == LFO::range_unsigned) {
                    denormalizer = max / (float) intLimit / 2.0;
                } else { // signed range
                    denormalizer = max / (float) intLimit * 2.0;
                    offset       = -max;
                }
            }

            /**
             * Will be called by the voice when the key / voice was triggered.
             *
             * @param Frequency       - frequency of the oscillator in Hz
             * @param StartLevel      - on which level the wave should start
             * @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
             */
            void trigger(float Frequency, LFO::start_level_t StartLevel, uint16_t InternalDepth, uint16_t ExtControlDepth, bool FlipPhase, 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
                if (RANGE == LFO::range_unsigned) {
                    this->InternalDepth        *= 2.0f;
                    this->ExtControlDepthCoeff *= 2.0f;
                }
                this->pFinalDepth = NULL;
                this->pFinalFrequency = NULL;

                this->flipPhaseFactor = FlipPhase ? -1 : 1;
                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 * this->flipPhaseFactor);

                const int slopeAtMid = (RANGE == LFO::range_unsigned) ? intLimit / 2 : intLimit;
                const int slopeAtMin = (RANGE == LFO::range_unsigned) ? intLimit : intLimit / 2;

                switch (StartLevel) {
                    case LFO::start_level_mid:
                        //slope = (FlipPhase) ? slopeAtMin : slopeAtMid;
                        slope = slopeAtMid;
                        break;

                    // with saw function, min and max are actually always the same thing
                    // (and no matter if FlipPhase or not)
                    case LFO::start_level_max:
                    case LFO::start_level_min:
                        slope = slopeAtMin;
                        break;
                }
            }

            /**
             * 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...
                slope += intLimit * phase * flipPhaseFactor;
            }

            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 * this->flipPhaseFactor);
            }

            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 slope;
            unsigned int c;
            float offset; ///< only needed for signed range
            float denormalizer;
            float flipPhaseFactor; ///< Factor instead of boolean to avoid branches.
    };

} // namespace LinuxSampler

#endif // LS_LFOSAWINTMATHNEW_H
1	schoenebeck	3612	/*
2			* Copyright (c) 2019 Christian Schoenebeck
3			*
4			* http://www.linuxsampler.org
5			*
6			* This file is part of LinuxSampler and released under the same terms.
7			* See README file for details.
8			*/
9
10	schoenebeck	3614	#ifndef LS_LFOSAWINTMATHNEW_H
11			#define LS_LFOSAWINTMATHNEW_H
12	schoenebeck	3612
13			#include <stdlib.h>
14			#include "LFOBase.h"
15
16			namespace LinuxSampler {
17
18			/** @brief Saw LFO (int math implementation)
19			*
20			* This is a Saw Low Frequency Oscillator which uses pure integer
21			* math (without branches) to synthesize the saw wave.
22			*/
23			template<LFO::range_type_t RANGE>
24	schoenebeck	3614	class LFOSawIntMathNew : public LFOBase<RANGE> {
25	schoenebeck	3612	public:
26			/**
27			* Constructor
28			*
29			* @param Max - maximum value of the output levels
30			*/
31	schoenebeck	3614	LFOSawIntMathNew(float Max) : LFOBase<RANGE>::LFOBase(Max) {
32	schoenebeck	3625	//NOTE: DO NOT add any custom initialization here, since it would break LFOCluster construction !
33	schoenebeck	3612	}
34
35			/**
36			* Calculates exactly one sample point of the LFO wave.
37			*
38			* @returns next LFO level
39			*/
40			inline float render() {
41			this->slope += this->c;
42			if (RANGE == LFO::range_unsigned)
43			return this->denormalizer * float(this->slope);
44			else // signed range
45			return this->denormalizer * float(int(this->slope) + this->offset);
46			}
47
48			/**
49			* Update LFO depth with a new external controller value.
50			*
51			* @param ExtControlValue - new external controller value
52			*/
53			inline void updateByMIDICtrlValue(const uint16_t& ExtControlValue) {
54			this->ExtControlValue = ExtControlValue;
55
56			const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
57			const float max = (this->InternalDepth + ExtControlValue * this->ExtControlDepthCoeff) * this->ScriptDepthFactor;
58			if (RANGE == LFO::range_unsigned) {
59			denormalizer = max / (float) intLimit / 2.0;
60			} else { // signed range
61			denormalizer = max / (float) intLimit * 2.0;
62			offset = -max;
63			}
64			}
65
66			/**
67			* Will be called by the voice when the key / voice was triggered.
68			*
69			* @param Frequency - frequency of the oscillator in Hz
70			* @param StartLevel - on which level the wave should start
71			* @param InternalDepth - firm, internal oscillator amplitude
72			* @param ExtControlDepth - defines how strong the external MIDI
73			* controller has influence on the
74			* oscillator amplitude
75			* @param FlipPhase - inverts the oscillator wave against
76			* a horizontal axis
77			* @param SampleRate - current sample rate of the engines
78			* audio output signal
79			*/
80			void trigger(float Frequency, LFO::start_level_t StartLevel, uint16_t InternalDepth, uint16_t ExtControlDepth, bool FlipPhase, unsigned int SampleRate) {
81			this->Frequency = Frequency;
82			this->InternalDepth = (InternalDepth / 1200.0f) * this->Max;
83			this->ExtControlDepthCoeff = (((float) ExtControlDepth / 1200.0f) / 127.0f) * this->Max;
84			this->ScriptFrequencyFactor = this->ScriptDepthFactor = 1.f; // reset for new voice
85			if (RANGE == LFO::range_unsigned) {
86			this->InternalDepth *= 2.0f;
87			this->ExtControlDepthCoeff *= 2.0f;
88			}
89			this->pFinalDepth = NULL;
90			this->pFinalFrequency = NULL;
91
92			this->flipPhaseFactor = FlipPhase ? -1 : 1;
93			const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
94			const float freq = Frequency * this->ScriptFrequencyFactor;
95			const float r = freq / (float) SampleRate; // frequency alteration quotient
96			c = int(intLimit * r * this->flipPhaseFactor);
97
98			const int slopeAtMid = (RANGE == LFO::range_unsigned) ? intLimit / 2 : intLimit;
99			const int slopeAtMin = (RANGE == LFO::range_unsigned) ? intLimit : intLimit / 2;
100
101			switch (StartLevel) {
102			case LFO::start_level_mid:
103			//slope = (FlipPhase) ? slopeAtMin : slopeAtMid;
104			slope = slopeAtMid;
105			break;
106
107			// with saw function, min and max are actually always the same thing
108			// (and no matter if FlipPhase or not)
109			case LFO::start_level_max:
110			case LFO::start_level_min:
111			slope = slopeAtMin;
112			break;
113			}
114			}
115
116			/**
117			* Should be invoked after the LFO is triggered.
118			* @param phase From 0 to 360 degrees.
119			*/
120			void setPhase(float phase) {
121			if (phase < 0) phase = 0;
122			if (phase > 360) phase = 360;
123			phase /= 360.0f;
124			const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
125			slope += intLimit * phase * flipPhaseFactor;
126			}
127
128			void setFrequency(float Frequency, unsigned int SampleRate) {
129			this->Frequency = Frequency;
130			const float freq = Frequency * this->ScriptFrequencyFactor;
131			const unsigned int intLimit = (unsigned int) -1; // all 0xFFFF...
132			float r = freq / (float) SampleRate; // frequency alteration quotient
133			c = int(intLimit * r * this->flipPhaseFactor);
134			}
135
136			void setScriptDepthFactor(float factor, bool isFinal) {
137			this->ScriptDepthFactor = factor;
138			// set or reset this script depth parameter to be the sole
139			// source for the LFO depth
140			if (isFinal && !this->pFinalDepth)
141			this->pFinalDepth = &this->ScriptDepthFactor;
142			else if (!isFinal && this->pFinalDepth == &this->ScriptDepthFactor)
143			this->pFinalDepth = NULL;
144			// recalculate upon new depth
145			updateByMIDICtrlValue(this->ExtControlValue);
146			}
147
148			void setScriptFrequencyFactor(float factor, unsigned int SampleRate) {
149			this->ScriptFrequencyFactor = factor;
150			// in case script frequency was set as "final" value before,
151			// reset it so that all sources are processed from now on
152			if (this->pFinalFrequency == &this->ScriptFrequencyFactor)
153			this->pFinalFrequency = NULL;
154			// recalculate upon new frequency
155			setFrequency(this->Frequency, SampleRate);
156			}
157
158			void setScriptFrequencyFinal(float hz, unsigned int SampleRate) {
159			this->ScriptFrequencyFactor = hz;
160			// assign script's given frequency as sole source for the LFO
161			// frequency, thus ignore all other sources
162			if (!this->pFinalFrequency)
163			this->pFinalFrequency = &this->ScriptFrequencyFactor;
164			// recalculate upon new frequency
165			setFrequency(this->Frequency, SampleRate);
166			}
167
168			protected:
169			unsigned int slope;
170			unsigned int c;
171			float offset; ///< only needed for signed range
172			float denormalizer;
173			float flipPhaseFactor; ///< Factor instead of boolean to avoid branches.
174			};
175
176			} // namespace LinuxSampler
177
178	schoenebeck	3614	#endif // LS_LFOSAWINTMATHNEW_H