Files
stk/projects/ragamatic/StrDrone.cpp
Gary Scavone 3f126af4e5 Version 3.2
2013-09-29 22:42:55 +02:00

78 lines
1.7 KiB
C++

/******************************************/
/* Karplus-Strong StrDrone string model */
/* by Perry Cook, 1995-96 */
/* */
/* There exist at least two patents, */
/* assigned to Stanford, bearing the */
/* names of Karplus and/or Strong. */
/******************************************/
#include "StrDrone.h"
StrDrone :: StrDrone(MY_FLOAT lowestFreq)
{
length = (long) (SRATE / lowestFreq + 1);
loopGain = (MY_FLOAT) 0.999;
loopFilt = new OneZero();
delayLine = new DLineA(length);
envelope = new ADSR();
noise = new Noise;
envelope->setAllTimes(2.0,0.5,0.0,0.5);
this->clear();
}
StrDrone :: ~StrDrone()
{
delete loopFilt;
delete delayLine;
delete envelope;
delete noise;
}
void StrDrone :: clear()
{
loopFilt->clear();
delayLine->clear();
}
void StrDrone :: setFreq(MY_FLOAT frequency)
{
MY_FLOAT delay;
delay = (SRATE / frequency);
delayLine->setDelay(delay - 0.5);
loopGain = (MY_FLOAT) 0.997 + (frequency * (MY_FLOAT) 0.000002);
if (loopGain>1.0) loopGain = (MY_FLOAT) 0.99999;
}
void StrDrone :: pluck(MY_FLOAT amplitude)
{
envelope->keyOn();
}
void StrDrone :: noteOn(MY_FLOAT freq, MY_FLOAT amp)
{
this->setFreq(freq);
this->pluck(amp);
#if defined(_debug_)
printf("StrDrone : NoteOn: Freq=%lf Amp=%lf\n",freq,amp);
#endif
}
void StrDrone :: noteOff(MY_FLOAT amp)
{
loopGain = (MY_FLOAT) 1.0 - amp;
#if defined(_debug_)
printf("StrDrone : NoteOff: Amp=%lf\n",amp);
#endif
}
MY_FLOAT StrDrone :: tick()
{
/* check this out */
/* here's the whole inner loop of the instrument!! */
lastOutput = delayLine->tick(loopFilt->tick((delayLine->lastOut() * loopGain))
+ (0.005 * envelope->tick() * noise->tick()));
return lastOutput;
}