The Synthesis ToolKit in C++ (STK)

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SineWave.h
1#ifndef STK_SINEWAVE_H
2#define STK_SINEWAVE_H
3
4const unsigned long TABLE_SIZE = 2048;
5
6#include "Generator.h"
7
8namespace stk {
9
10/***************************************************/
23/***************************************************/
24
25 class SineWave : public Generator
26{
27public:
29 SineWave( void );
30
32 ~SineWave( void );
33
35 void reset( void );
36
38
41 void setRate( StkFloat rate ) { rate_ = rate; };
42
44
50 void setFrequency( StkFloat frequency );
51
53 void addTime( StkFloat time );
54
56
61 void addPhase( StkFloat phase );
62
64
68 void addPhaseOffset( StkFloat phaseOffset );
69
71 StkFloat lastOut( void ) const { return lastFrame_[0]; };
72
74 StkFloat tick( void );
75
77
84 StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
85
86protected:
87
88 void sampleRateChanged( StkFloat newRate, StkFloat oldRate );
89
90 static StkFrames table_;
91 StkFloat time_;
92 StkFloat rate_;
93 StkFloat phaseOffset_;
94 unsigned int iIndex_;
95 StkFloat alpha_;
96
97};
98
99 inline StkFloat SineWave :: tick( void )
100{
101 // Check limits of time address ... if necessary, recalculate modulo
102 // TABLE_SIZE.
103 while ( time_ < 0.0 )
104 time_ += TABLE_SIZE;
105 while ( time_ >= TABLE_SIZE )
106 time_ -= TABLE_SIZE;
107
108 iIndex_ = (unsigned int) time_;
109 alpha_ = time_ - iIndex_;
110 StkFloat tmp = table_[ iIndex_ ];
111 tmp += ( alpha_ * ( table_[ iIndex_ + 1 ] - tmp ) );
112
113 // Increment time, which can be negative.
114 time_ += rate_;
115
116 lastFrame_[0] = tmp;
117 return lastFrame_[0];
118}
119
120 inline StkFrames& SineWave :: tick( StkFrames& frames, unsigned int channel )
121{
122#if defined(_STK_DEBUG_)
123 if ( channel >= frames.channels() ) {
124 oStream_ << "SineWave::tick(): channel and StkFrames arguments are incompatible!";
125 handleError( StkError::FUNCTION_ARGUMENT );
126 }
127#endif
128
129 StkFloat *samples = &frames[channel];
130 StkFloat tmp = 0.0;
131
132 unsigned int hop = frames.channels();
133 for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
134
135 // Check limits of time address ... if necessary, recalculate modulo
136 // TABLE_SIZE.
137 while ( time_ < 0.0 )
138 time_ += TABLE_SIZE;
139 while ( time_ >= TABLE_SIZE )
140 time_ -= TABLE_SIZE;
141
142 iIndex_ = (unsigned int) time_;
143 alpha_ = time_ - iIndex_;
144 tmp = table_[ iIndex_ ];
145 tmp += ( alpha_ * ( table_[ iIndex_ + 1 ] - tmp ) );
146 *samples = tmp;
147
148 // Increment time, which can be negative.
149 time_ += rate_;
150 }
151
152 lastFrame_[0] = tmp;
153 return frames;
154}
155
156} // stk namespace
157
158#endif
159
stk::Generator
STK abstract unit generator parent class.
Definition Generator.h:21
stk::SineWave
STK sinusoid oscillator class.
Definition SineWave.h:26
stk::SineWave::setFrequency
void setFrequency(StkFloat frequency)
Set the data interpolation rate based on a looping frequency.
stk::SineWave::tick
StkFloat tick(void)
Compute and return one output sample.
Definition SineWave.h:99
stk::SineWave::lastOut
StkFloat lastOut(void) const
Return the last computed output value.
Definition SineWave.h:71
stk::SineWave::addPhase
void addPhase(StkFloat phase)
Increment the read pointer by a normalized phase value.
stk::SineWave::reset
void reset(void)
Clear output and reset time pointer to zero.
stk::SineWave::addPhaseOffset
void addPhaseOffset(StkFloat phaseOffset)
Add a normalized phase offset to the read pointer.
stk::SineWave::SineWave
SineWave(void)
Default constructor.
stk::SineWave::addTime
void addTime(StkFloat time)
Increment the read pointer by time in samples, modulo the table size.
stk::SineWave::~SineWave
~SineWave(void)
Class destructor.
stk::SineWave::setRate
void setRate(StkFloat rate)
Set the data read rate in samples. The rate can be negative.
Definition SineWave.h:41
stk::StkFrames
An STK class to handle vectorized audio data.
Definition Stk.h:279
stk::StkFrames::channels
unsigned int channels(void) const
Return the number of channels represented by the data.
Definition Stk.h:416
stk::StkFrames::frames
unsigned int frames(void) const
Return the number of sample frames represented by the data.
Definition Stk.h:419
stk
The STK namespace.
Definition ADSR.h:6

The Synthesis ToolKit in C++ (STK)
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