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Version 4.1

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This commit is contained in:
Gary Scavone
2009-03-24 23:02:12 -04:00
committed by Stephen Sinclair
parent 81475b04c5
commit 2f09fcd019
279 changed files with 36223 additions and 25364 deletions
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186
src/TwoPole.cpp
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@@ -1,93 +1,93 @@
/***************************************************/
/*! \class TwoPole
\brief STK two-pole filter class.
This protected Filter subclass implements
a two-pole digital filter. A method is
provided for creating a resonance in the
frequency response while maintaining a nearly
constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995 - 2002.
*/
/***************************************************/
#include "TwoPole.h"
#include <math.h>
TwoPole :: TwoPole() : Filter()
{
MY_FLOAT B = 1.0;
MY_FLOAT A[3] = {1.0, 0.0, 0.0};
Filter::setCoefficients( 1, &B, 3, A );
}
TwoPole :: ~TwoPole()
{
}
void TwoPole :: clear(void)
{
Filter::clear();
}
void TwoPole :: setB0(MY_FLOAT b0)
{
b[0] = b0;
}
void TwoPole :: setA1(MY_FLOAT a1)
{
a[1] = a1;
}
void TwoPole :: setA2(MY_FLOAT a2)
{
a[2] = a2;
}
void TwoPole :: setResonance(MY_FLOAT frequency, MY_FLOAT radius, bool normalize)
{
a[2] = radius * radius;
a[1] = (MY_FLOAT) -2.0 * radius * cos(TWO_PI * frequency / Stk::sampleRate());
if ( normalize ) {
// Normalize the filter gain ... not terribly efficient.
MY_FLOAT real = 1 - radius + (a[2] - radius) * cos(TWO_PI * 2 * frequency / Stk::sampleRate());
MY_FLOAT imag = (a[2] - radius) * sin(TWO_PI * 2 * frequency / Stk::sampleRate());
b[0] = sqrt( pow(real, 2) + pow(imag, 2) );
}
}
void TwoPole :: setGain(MY_FLOAT theGain)
{
Filter::setGain(theGain);
}
MY_FLOAT TwoPole :: getGain(void) const
{
return Filter::getGain();
}
MY_FLOAT TwoPole :: lastOut(void) const
{
return Filter::lastOut();
}
MY_FLOAT TwoPole :: tick(MY_FLOAT sample)
{
inputs[0] = gain * sample;
outputs[0] = b[0] * inputs[0] - a[2] * outputs[2] - a[1] * outputs[1];
outputs[2] = outputs[1];
outputs[1] = outputs[0];
return outputs[0];
}
MY_FLOAT *TwoPole :: tick(MY_FLOAT *vector, unsigned int vectorSize)
{
for (unsigned int i=0; i<vectorSize; i++)
vector[i] = tick(vector[i]);
return vector;
}
/***************************************************/
/*! \class TwoPole
\brief STK two-pole filter class.
This protected Filter subclass implements
a two-pole digital filter. A method is
provided for creating a resonance in the
frequency response while maintaining a nearly
constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995 - 2002.
*/
/***************************************************/
#include "TwoPole.h"
#include <math.h>
TwoPole :: TwoPole() : Filter()
{
MY_FLOAT B = 1.0;
MY_FLOAT A[3] = {1.0, 0.0, 0.0};
Filter::setCoefficients( 1, &B, 3, A );
}
TwoPole :: ~TwoPole()
{
}
void TwoPole :: clear(void)
{
Filter::clear();
}
void TwoPole :: setB0(MY_FLOAT b0)
{
b[0] = b0;
}
void TwoPole :: setA1(MY_FLOAT a1)
{
a[1] = a1;
}
void TwoPole :: setA2(MY_FLOAT a2)
{
a[2] = a2;
}
void TwoPole :: setResonance(MY_FLOAT frequency, MY_FLOAT radius, bool normalize)
{
a[2] = radius * radius;
a[1] = (MY_FLOAT) -2.0 * radius * cos(TWO_PI * frequency / Stk::sampleRate());
if ( normalize ) {
// Normalize the filter gain ... not terribly efficient.
MY_FLOAT real = 1 - radius + (a[2] - radius) * cos(TWO_PI * 2 * frequency / Stk::sampleRate());
MY_FLOAT imag = (a[2] - radius) * sin(TWO_PI * 2 * frequency / Stk::sampleRate());
b[0] = sqrt( pow(real, 2) + pow(imag, 2) );
}
}
void TwoPole :: setGain(MY_FLOAT theGain)
{
Filter::setGain(theGain);
}
MY_FLOAT TwoPole :: getGain(void) const
{
return Filter::getGain();
}
MY_FLOAT TwoPole :: lastOut(void) const
{
return Filter::lastOut();
}
MY_FLOAT TwoPole :: tick(MY_FLOAT sample)
{
inputs[0] = gain * sample;
outputs[0] = b[0] * inputs[0] - a[2] * outputs[2] - a[1] * outputs[1];
outputs[2] = outputs[1];
outputs[1] = outputs[0];
return outputs[0];
}
MY_FLOAT *TwoPole :: tick(MY_FLOAT *vector, unsigned int vectorSize)
{
for (unsigned int i=0; i<vectorSize; i++)
vector[i] = tick(vector[i]);
return vector;
}