1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
#ifndef STK_BEETHREE_H
#define STK_BEETHREE_H
#include "FM.h"
namespace stk {
/***************************************************/
/*! \class BeeThree
\brief STK Hammond-oid organ FM synthesis instrument.
This class implements a simple 4 operator
topology, also referred to as algorithm 8 of
the TX81Z.
\code
Algorithm 8 is :
1 --.
2 -\|
+-> Out
3 -/|
4 --
\endcode
Control Change Numbers:
- Operator 4 (feedback) Gain = 2
- Operator 3 Gain = 4
- LFO Speed = 11
- LFO Depth = 1
- ADSR 2 & 4 Target = 128
The basic Chowning/Stanford FM patent expired
in 1995, but there exist follow-on patents,
mostly assigned to Yamaha. If you are of the
type who should worry about this (making
money) worry away.
by Perry R. Cook and Gary P. Scavone, 1995--2021.
*/
/***************************************************/
class BeeThree : public FM
{
public:
//! Class constructor.
/*!
An StkError will be thrown if the rawwave path is incorrectly set.
*/
BeeThree( void );
//! Class destructor.
~BeeThree( void );
//! Start a note with the given frequency and amplitude.
void noteOn( StkFloat frequency, StkFloat amplitude );
//! Compute and return one output sample.
StkFloat tick( unsigned int channel = 0 );
//! Fill a channel of the StkFrames object with computed outputs.
/*!
The \c channel argument must be less than the number of
channels in the StkFrames argument (the first channel is specified
by 0). However, range checking is only performed if _STK_DEBUG_
is defined during compilation, in which case an out-of-range value
will trigger an StkError exception.
*/
StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
protected:
};
inline StkFloat BeeThree :: tick( unsigned int )
{
StkFloat temp;
if ( modDepth_ > 0.0 ) {
temp = 1.0 + ( modDepth_ * vibrato_.tick() * 0.1 );
waves_[0]->setFrequency( baseFrequency_ * temp * ratios_[0] );
waves_[1]->setFrequency( baseFrequency_ * temp * ratios_[1] );
waves_[2]->setFrequency( baseFrequency_ * temp * ratios_[2] );
waves_[3]->setFrequency( baseFrequency_ * temp * ratios_[3] );
}
waves_[3]->addPhaseOffset( twozero_.lastOut() );
temp = control1_ * 2.0 * gains_[3] * adsr_[3]->tick() * waves_[3]->tick();
twozero_.tick( temp );
temp += control2_ * 2.0 * gains_[2] * adsr_[2]->tick() * waves_[2]->tick();
temp += gains_[1] * adsr_[1]->tick() * waves_[1]->tick();
temp += gains_[0] * adsr_[0]->tick() * waves_[0]->tick();
lastFrame_[0] = temp * 0.125;
return lastFrame_[0];
}
inline StkFrames& BeeThree :: tick( StkFrames& frames, unsigned int channel )
{
unsigned int nChannels = lastFrame_.channels();
#if defined(_STK_DEBUG_)
if ( channel > frames.channels() - nChannels ) {
oStream_ << "BeeThree::tick(): channel and StkFrames arguments are incompatible!";
handleError( StkError::FUNCTION_ARGUMENT );
}
#endif
StkFloat *samples = &frames[channel];
unsigned int j, hop = frames.channels() - nChannels;
if ( nChannels == 1 ) {
for ( unsigned int i=0; i<frames.frames(); i++, samples += hop )
*samples++ = tick();
}
else {
for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
*samples++ = tick();
for ( j=1; j<nChannels; j++ )
*samples++ = lastFrame_[j];
}
}
return frames;
}
} // stk namespace
#endif
|
