The Synthesis ToolKit in C++ (STK)

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Bowed.h
1 #ifndef STK_BOWED_H
2 #define STK_BOWED_H
3
4 #include "Instrmnt.h"
5 #include "DelayL.h"
6 #include "BowTable.h"
7 #include "OnePole.h"
8 #include "BiQuad.h"
9 #include "SineWave.h"
10 #include "ADSR.h"
11
12 namespace stk {
13
14 /***************************************************/
38 /***************************************************/
39
40 class Bowed : public Instrmnt
41 {
42 public:
44 Bowed( StkFloat lowestFrequency = 8.0 );
45
47 ~Bowed( void );
48
50 void clear( void );
51
53 void setFrequency( StkFloat frequency );
54
56 void setVibrato( StkFloat gain ) { vibratoGain_ = gain; };
57
59 void startBowing( StkFloat amplitude, StkFloat rate );
60
62 void stopBowing( StkFloat rate );
63
65 void noteOn( StkFloat frequency, StkFloat amplitude );
66
68 void noteOff( StkFloat amplitude );
69
71 void controlChange( int number, StkFloat value );
72
74 StkFloat tick( unsigned int channel = 0 );
75
77
84 StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
85
86 protected:
87
88 DelayL neckDelay_;
89 DelayL bridgeDelay_;
90 BowTable bowTable_;
91 OnePole stringFilter_;
92 BiQuad bodyFilters_[6];
93 SineWave vibrato_;
94 ADSR adsr_;
95
96 bool bowDown_;
97 StkFloat maxVelocity_;
98 StkFloat baseDelay_;
99 StkFloat vibratoGain_;
100 StkFloat betaRatio_;
101
102 };
103
104 inline StkFloat Bowed :: tick( unsigned int )
105 {
106 StkFloat bowVelocity = maxVelocity_ * adsr_.tick();
107 StkFloat bridgeReflection = -stringFilter_.tick( bridgeDelay_.lastOut() );
108 StkFloat nutReflection = -neckDelay_.lastOut();
109 StkFloat stringVelocity = bridgeReflection + nutReflection;
110 StkFloat deltaV = bowVelocity - stringVelocity; // Differential velocity
111
112 StkFloat newVelocity = 0.0;
113 if ( bowDown_ )
114 newVelocity = deltaV * bowTable_.tick( deltaV ); // Non-Linear bow function
115 neckDelay_.tick( bridgeReflection + newVelocity); // Do string propagations
116 bridgeDelay_.tick(nutReflection + newVelocity);
117
118 if ( vibratoGain_ > 0.0 ) {
119 neckDelay_.setDelay( (baseDelay_ * (1.0 - betaRatio_) ) +
120 (baseDelay_ * vibratoGain_ * vibrato_.tick()) );
121 }
122
123 lastFrame_[0] = 0.1248 * bodyFilters_[5].tick( bodyFilters_[4].tick( bodyFilters_[3].tick( bodyFilters_[2].tick( bodyFilters_[1].tick( bodyFilters_[0].tick( bridgeDelay_.lastOut() ) ) ) ) ) );
124
125 return lastFrame_[0];
126 }
127
128 inline StkFrames& Bowed :: tick( StkFrames& frames, unsigned int channel )
129 {
130 unsigned int nChannels = lastFrame_.channels();
131 #if defined(_STK_DEBUG_)
132 if ( channel > frames.channels() - nChannels ) {
133 oStream_ << "Bowed::tick(): channel and StkFrames arguments are incompatible!";
134 handleError( StkError::FUNCTION_ARGUMENT );
135 }
136 #endif
137
138 StkFloat *samples = &frames[channel];
139 unsigned int j, hop = frames.channels() - nChannels;
140 if ( nChannels == 1 ) {
141 for ( unsigned int i=0; i<frames.frames(); i++, samples += hop )
142 *samples++ = tick();
143 }
144 else {
145 for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
146 *samples++ = tick();
147 for ( j=1; j<nChannels; j++ )
148 *samples++ = lastFrame_[j];
149 }
150 }
151
152 return frames;
153 }
154
155 } // stk namespace
156
157 #endif

The Synthesis ToolKit in C++ (STK)
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