[PD-cvs] externals/sc4pd/source HPF.cpp,NONE,1.1 LPF.cpp,NONE,1.1 RHPF.cpp,NONE,1.1 RLPF.cpp,NONE,1.1 SOS.cpp,1.1,1.2 main.cpp,1.23,1.24 support.hpp,1.7,1.8

Sun Aug 8 13:10:32 CEST 2004

Update of /cvsroot/pure-data/externals/sc4pd/source
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv27366/source

Modified Files:
	SOS.cpp main.cpp support.hpp 
Added Files:
	HPF.cpp LPF.cpp RHPF.cpp RLPF.cpp 
Log Message:
some filters

Index: support.hpp
===================================================================
RCS file: /cvsroot/pure-data/externals/sc4pd/source/support.hpp,v
retrieving revision 1.7
retrieving revision 1.8
diff -C2 -d -r1.7 -r1.8
*** support.hpp	3 Aug 2004 17:51:51 -0000	1.7
--- support.hpp	8 Aug 2004 11:10:30 -0000	1.8
***************
*** 123,126 ****
--- 123,135 ----
  #define SIGFUN(FUN) &thisType::FUN

+ #undef F
+ #undef D
+ #undef I
+ #undef L
+ #undef C
+ #undef V
+ #undef BL
+ #undef S
+ 

  #endif

Index: main.cpp
===================================================================
RCS file: /cvsroot/pure-data/externals/sc4pd/source/main.cpp,v
retrieving revision 1.23
retrieving revision 1.24
diff -C2 -d -r1.23 -r1.24
*** main.cpp	7 Aug 2004 22:56:22 -0000	1.23
--- main.cpp	8 Aug 2004 11:10:30 -0000	1.24
***************
*** 65,69 ****
  	 "          AllpassC~, PitchShift~, Resonz~, OnePole(~), OneZero(~), "
  	 "TwoPole~, \n"
! 	 "          TwoZero~, FOS(~), SOS~"
  	 "\n"
  	 );
--- 65,69 ----
  	 "          AllpassC~, PitchShift~, Resonz~, OnePole(~), OneZero(~), "
  	 "TwoPole~, \n"
! 	 "          TwoZero~, FOS(~), SOS~, RLPF~, RHPF~, LPF~, HPF~"
  	 "\n"
  	 );
***************
*** 250,253 ****
--- 250,261 ----

      FLEXT_DSP_SETUP(SOS_ar); 
+ 
+     FLEXT_DSP_SETUP(RLPF_ar); 
+ 
+     FLEXT_DSP_SETUP(RHPF_ar); 
+ 
+     FLEXT_DSP_SETUP(LPF_ar); 
+ 
+     FLEXT_DSP_SETUP(HPF_ar); 
  }

--- NEW FILE: LPF.cpp ---
/* sc4pd 
   LPF~

   Copyright (c) 2004 Tim Blechmann.

   This code is derived from:
	SuperCollider real time audio synthesis system
    Copyright (c) 2002 James McCartney. All rights reserved.
	http://www.audiosynth.com

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 2
   of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

   Based on:
     PureData by Miller Puckette and others.
         http://www.crca.ucsd.edu/~msp/software.html
     FLEXT by Thomas Grill
         http://www.parasitaere-kapazitaeten.net/ext
     SuperCollider by James McCartney
         http://www.audiosynth.com

   Coded while listening to: Peter Kowald & Tatsuya Nakatani: 
                             13 Definitions of Truth

*/

#include "sc4pd.hpp"

/* ------------------------ LPF~ -------------------------------*/

class LPF_ar:
    public sc4pd_dsp
{
    FLEXT_HEADER(LPF_ar,sc4pd_dsp);

public:
    LPF_ar(int argc, t_atom *argv);

protected:
    virtual void m_signal(int n, t_sample *const *in, t_sample *const *out);
    virtual void m_dsp(int n, t_sample *const *in, t_sample *const *out)
    {
	mRadiansPerSample = sc_radianspersample();
	mFilterSlope = sc_filterslope();
	mFilterLoops = sc_filterloops();
	mFilterRemain = sc_filterremain();
    }

    void m_set_freq(float f)
    {
	m_freq=f;
	changed = true;
    }

private:
    float m_y1, m_y2, m_a0, m_b1, m_b2, m_freq;
    bool changed;
    float mRadiansPerSample, mFilterSlope;
    int mFilterLoops, mFilterRemain; 

    FLEXT_CALLBACK_F(m_set_freq);
};

FLEXT_LIB_DSP_V("LPF~",LPF_ar);

LPF_ar::LPF_ar(int argc, t_atom *argv)
{
    FLEXT_ADDMETHOD_(0,"kfreq",m_set_freq);

    //parse arguments
    AtomList Args(argc,argv);

    m_freq = sc_getfloatarg(Args,0);
    changed = true;

    AddOutSignal();

    m_a0 = 0.f;
    m_b1 = 0.f;
    m_b2 = 0.f;
    m_y1 = 0.f;
    m_y2 = 0.f;
}

void LPF_ar::m_signal(int n, t_sample *const *in, 
			  t_sample *const *out)
{
    t_sample *nin = *in;
    t_sample *nout = *out;

    float y0;
    float y1 = m_y1;
    float y2 = m_y2;
    float a0 = m_a0;
    float b1 = m_b1;
    float b2 = m_b2;

    if (changed)
    {
	float pfreq = m_freq * mRadiansPerSample * 0.5;

	float C = 1.f / tan(pfreq);
	float C2 = C * C;
	float sqrt2C = C * sqrt2;
	float next_a0 = 1.f / (1.f + sqrt2C + C2);
	float next_b1 = -2.f * (1.f - C2) * next_a0 ;
	float next_b2 = -(1.f - sqrt2C + C2) * next_a0;

	float a0_slope = (next_a0 - a0) * mFilterSlope;
	float b1_slope = (next_b1 - b1) * mFilterSlope;
	float b2_slope = (next_b2 - b2) * mFilterSlope;

	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 + 2.f * y1 + y2);

	    y2 = ZXP(nin) + b1 * y0 + b2 * y1; 
	    ZXP(nout) = a0 * (y2 + 2.f * y0 + y1);

	    y1 = ZXP(nin) + b1 * y2 + b2 * y0; 
	    ZXP(nout) = a0 * (y1 + 2.f * y2 + y0);

	    a0 += a0_slope; 
	    b1 += b1_slope; 
	    b2 += b2_slope;
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 + 2.f * y1 + y2);
	    y2 = y1; 
	    y1 = y0;
	}

	m_a0 = a0;
	m_b1 = b1;
	m_b2 = b2;
	changed = false;
    }
    else
    {
	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 + 2.f * y1 + y2);

	    y2 = ZXP(nin) + b1 * y0 + b2 * y1; 
	    ZXP(nout) = a0 * (y2 + 2.f * y0 + y1);

	    y1 = ZXP(nin) + b1 * y2 + b2 * y0; 
	    ZXP(nout) = a0 * (y1 + 2.f * y2 + y0);
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 + 2.f * y1 + y2);
	    y2 = y1; 
	    y1 = y0;
	}
    }
    m_y1 = zapgremlins(y1);
    m_y2 = zapgremlins(y2);
}

/* no control rate LPF filter */

--- NEW FILE: HPF.cpp ---
/* sc4pd 
   HPF~

   Copyright (c) 2004 Tim Blechmann.

   This code is derived from:
	SuperCollider real time audio synthesis system
    Copyright (c) 2002 James McCartney. All rights reserved.
	http://www.audiosynth.com

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 2
   of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

   Based on:
     PureData by Miller Puckette and others.
         http://www.crca.ucsd.edu/~msp/software.html
     FLEXT by Thomas Grill
         http://www.parasitaere-kapazitaeten.net/ext
     SuperCollider by James McCartney
         http://www.audiosynth.com

   Coded while listening to: Peter Kowald & Tatsuya Nakatani: 
                             13 Definitions of Truth

*/

#include "sc4pd.hpp"

/* ------------------------ HPF~ -------------------------------*/

class HPF_ar:
    public sc4pd_dsp
{
    FLEXT_HEADER(HPF_ar,sc4pd_dsp);

public:
    HPF_ar(int argc, t_atom *argv);

protected:
    virtual void m_signal(int n, t_sample *const *in, t_sample *const *out);
    virtual void m_dsp(int n, t_sample *const *in, t_sample *const *out)
    {
	mRadiansPerSample = sc_radianspersample();
	mFilterSlope = sc_filterslope();
	mFilterLoops = sc_filterloops();
	mFilterRemain = sc_filterremain();
    }

    void m_set_freq(float f)
    {
	m_freq=f;
	changed = true;
    }

private:
    float m_y1, m_y2, m_a0, m_b1, m_b2, m_freq;
    bool changed;
    float mRadiansPerSample, mFilterSlope;
    int mFilterLoops, mFilterRemain; 

    FLEXT_CALLBACK_F(m_set_freq);
};

FLEXT_LIB_DSP_V("HPF~",HPF_ar);

HPF_ar::HPF_ar(int argc, t_atom *argv)
{
    FLEXT_ADDMETHOD_(0,"kfreq",m_set_freq);

    //parse arguments
    AtomList Args(argc,argv);

    m_freq = sc_getfloatarg(Args,0);
    changed = true;

    AddOutSignal();

    m_a0 = 0.f;
    m_b1 = 0.f;
    m_b2 = 0.f;
    m_y1 = 0.f;
    m_y2 = 0.f;
}

void HPF_ar::m_signal(int n, t_sample *const *in, 
			  t_sample *const *out)
{
    t_sample *nin = *in;
    t_sample *nout = *out;

    float y0;
    float y1 = m_y1;
    float y2 = m_y2;
    float a0 = m_a0;
    float b1 = m_b1;
    float b2 = m_b2;

    if (changed)
    {
	float pfreq = m_freq * mRadiansPerSample * 0.5;

	float C = tan(pfreq);
	float C2 = C * C;
	float sqrt2C = C * sqrt2;
	float next_a0 = 1.f / (1.f + sqrt2C + C2);
	float next_b1 = 2.f * (1.f - C2) * next_a0 ;
	float next_b2 = -(1.f - sqrt2C + C2) * next_a0;

	float a0_slope = (next_a0 - a0) * mFilterSlope;
	float b1_slope = (next_b1 - b1) * mFilterSlope;
	float b2_slope = (next_b2 - b2) * mFilterSlope;

	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 - 2.f * y1 + y2);

	    y2 = ZXP(nin) + b1 * y0 + b2 * y1; 
	    ZXP(nout) = a0 * (y2 - 2.f * y0 + y1);

	    y1 = ZXP(nin) + b1 * y2 + b2 * y0; 
	    ZXP(nout) = a0 * (y1 - 2.f * y2 + y0);

	    a0 += a0_slope; 
	    b1 += b1_slope; 
	    b2 += b2_slope;
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 - 2.f * y1 + y2);
	    y2 = y1; 
	    y1 = y0;
	}

	m_a0 = a0;
	m_b1 = b1;
	m_b2 = b2;
	changed = false;
    }
    else
    {
	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 - 2.f * y1 + y2);

	    y2 = ZXP(nin) + b1 * y0 + b2 * y1; 
	    ZXP(nout) = a0 * (y2 - 2.f * y0 + y1);

	    y1 = ZXP(nin) + b1 * y2 + b2 * y0; 
	    ZXP(nout) = a0 * (y1 - 2.f * y2 + y0);
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
	    ZXP(nout) = a0 * (y0 - 2.f * y1 + y2);
	    y2 = y1; 
	    y1 = y0;
	}
    }
    m_y1 = zapgremlins(y1);
    m_y2 = zapgremlins(y2);
}

/* no control rate HPF filter */

--- NEW FILE: RHPF.cpp ---
/* sc4pd 
   RHPF~

   Copyright (c) 2004 Tim Blechmann.

   This code is derived from:
	SuperCollider real time audio synthesis system
    Copyright (c) 2002 James McCartney. All rights reserved.
	http://www.audiosynth.com

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 2
   of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

   Based on:
     PureData by Miller Puckette and others.
         http://www.crca.ucsd.edu/~msp/software.html
     FLEXT by Thomas Grill
         http://www.parasitaere-kapazitaeten.net/ext
     SuperCollider by James McCartney
         http://www.audiosynth.com

   Coded while listening to: Peter Kowald & Tatsuya Nakatani: 
                             13 Definitions of Truth

*/

#include "sc4pd.hpp"

/* ------------------------ RHPF~ -------------------------------*/

class RHPF_ar:
    public sc4pd_dsp
{
    FLEXT_HEADER(RHPF_ar,sc4pd_dsp);

public:
    RHPF_ar(int argc, t_atom *argv);

protected:
    virtual void m_signal(int n, t_sample *const *in, t_sample *const *out);
    virtual void m_dsp(int n, t_sample *const *in, t_sample *const *out)
    {
	mRadiansPerSample = sc_radianspersample();
	mFilterSlope = sc_filterslope();
	mFilterLoops = sc_filterloops();
	mFilterRemain = sc_filterremain();
    }

    void m_set_freq(float f)
    {
	m_freq=f;
	changed = true;
    }

    void m_set_rq(float f)
    {
	m_reson=f;
	changed = true;
    }

private:
    float m_y1, m_y2, m_a0, m_b1, m_b2, m_freq, m_reson;
    bool changed;
    float mRadiansPerSample, mFilterSlope;
    int mFilterLoops, mFilterRemain; 

    FLEXT_CALLBACK_F(m_set_freq);
    FLEXT_CALLBACK_F(m_set_rq);
};

FLEXT_LIB_DSP_V("RHPF~",RHPF_ar);

RHPF_ar::RHPF_ar(int argc, t_atom *argv)
{
    FLEXT_ADDMETHOD_(0,"kfreq",m_set_freq);
    FLEXT_ADDMETHOD_(0,"krq",m_set_rq);

    //parse arguments
    AtomList Args(argc,argv);

    m_freq = sc_getfloatarg(Args,0);
    m_reson = sc_getfloatarg(Args,1);
    changed = true;

    AddOutSignal();

    m_a0 = 0.f;
    m_b1 = 0.f;
    m_b2 = 0.f;
    m_y1 = 0.f;
    m_y2 = 0.f;
}

void RHPF_ar::m_signal(int n, t_sample *const *in, 
			  t_sample *const *out)
{
    t_sample *nin = *in;
    t_sample *nout = *out;

    float y0;
    float y1 = m_y1;
    float y2 = m_y2;
    float a0 = m_a0;
    float b1 = m_b1;
    float b2 = m_b2;

    if (changed)
    {
	float qres = sc_max(0.001, m_reson);
	float pfreq = m_freq * mRadiansPerSample;

	float D = tan(pfreq * qres * 0.5);
	float C = ((1.f-D)/(1.f+D));
	float cosf = cos(pfreq);

	float next_b1 = (1.f + C) * cosf;	
	float next_b2 = -C;
	float next_a0 = (1.f + C + next_b1) * .25;

	float a0_slope = (next_a0 - a0) * mFilterSlope;
	float b1_slope = (next_b1 - b1) * mFilterSlope;
	float b2_slope = (next_b2 - b2) * mFilterSlope;

	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 - 2.f * y1 + y2;

	    y2 = a0 * ZXP(nin) + b1 * y0 + b2 * y1;
	    ZXP(nout) = y2 - 2.f * y0 + y1;

	    y1 = a0 * ZXP(nin) + b1 * y2 + b2 * y0;
	    ZXP(nout) = y1 - 2.f * y2 + y0;

	    a0 += a0_slope; 
	    b1 += b1_slope; 
	    b2 += b2_slope;
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 - 2.f * y1 + y2;
	    y2 = y1; 
	    y1 = y0;
	}

	m_a0 = a0;
	m_b1 = b1;
	m_b2 = b2;
	changed = false;
    }
    else
    {
	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 - 2.f * y1 + y2;

	    y2 = a0 * ZXP(nin) + b1 * y0 + b2 * y1;
	    ZXP(nout) = y2 - 2.f * y0 + y1;

	    y1 = a0 * ZXP(nin) + b1 * y2 + b2 * y0;
	    ZXP(nout) = y1 - 2.f * y2 + y0;
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 - 2.f * y1 + y2;
	    y2 = y1; 
	    y1 = y0;
	}
    }
    m_y1 = zapgremlins(y1);
    m_y2 = zapgremlins(y2);
}

/* no control rate RHPF filter */

Index: SOS.cpp
===================================================================
RCS file: /cvsroot/pure-data/externals/sc4pd/source/SOS.cpp,v
retrieving revision 1.1
retrieving revision 1.2
diff -C2 -d -r1.1 -r1.2
*** SOS.cpp	7 Aug 2004 22:56:21 -0000	1.1
--- SOS.cpp	8 Aug 2004 11:10:30 -0000	1.2
***************
*** 144,148 ****
      if(sc_ar(Args))
      {
- 	SETSIGFUN(m_signal_fun,SIGFUN(m_signal_ar));
  	AddInSignal();
  	AddInSignal();
--- 144,147 ----
***************
*** 151,154 ****
--- 150,154 ----
  	AddInSignal();
  	AddInSignal();
+ 	SETSIGFUN(m_signal_fun,SIGFUN(m_signal_ar));
      }
      else // if not given, use control rate
***************
*** 191,196 ****
  	ZXP(nout) = ZXP(a0) * y1 + ZXP(a1) * y2 + ZXP(a2) * y0;
      }
! 
!     for (int i = 0; i!= mFilterLoops;++i)
      {
  	y0 = ZXP(nin) + ZXP(b1) * y1 + ZXP(b2) * y2; 
--- 191,196 ----
  	ZXP(nout) = ZXP(a0) * y1 + ZXP(a1) * y2 + ZXP(a2) * y0;
      }
!     
!     for (int i = 0; i!= mFilterRemain;++i)
      {
  	y0 = ZXP(nin) + ZXP(b1) * y1 + ZXP(b2) * y2; 
***************
*** 199,203 ****
  	y1 = y0;
      }
!     
      m_y1 = zapgremlins(y1);
      m_y2 = zapgremlins(y2);
--- 199,203 ----
  	y1 = y0;
      }
! 
      m_y1 = zapgremlins(y1);
      m_y2 = zapgremlins(y2);
***************
*** 244,248 ****
      }

!     for (int i = 0; i!= mFilterLoops;++i)
      {
  	y0 = ZXP(nin) + b1 * y1 + b2 * y2; 
--- 244,248 ----
      }

!     for (int i = 0; i!= mFilterRemain;++i)
      {
  	y0 = ZXP(nin) + b1 * y1 + b2 * y2; 

--- NEW FILE: RLPF.cpp ---
/* sc4pd 
   RLPF~

   Copyright (c) 2004 Tim Blechmann.

   This code is derived from:
	SuperCollider real time audio synthesis system
    Copyright (c) 2002 James McCartney. All rights reserved.
	http://www.audiosynth.com

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 2
   of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

   Based on:
     PureData by Miller Puckette and others.
         http://www.crca.ucsd.edu/~msp/software.html
     FLEXT by Thomas Grill
         http://www.parasitaere-kapazitaeten.net/ext
     SuperCollider by James McCartney
         http://www.audiosynth.com

   Coded while listening to: Peter Kowald & Tatsuya Nakatani: 
                             13 Definitions of Truth

*/

#include "sc4pd.hpp"

/* ------------------------ RLPF~ -------------------------------*/

class RLPF_ar:
    public sc4pd_dsp
{
    FLEXT_HEADER(RLPF_ar,sc4pd_dsp);

public:
    RLPF_ar(int argc, t_atom *argv);

protected:
    virtual void m_signal(int n, t_sample *const *in, t_sample *const *out);
    virtual void m_dsp(int n, t_sample *const *in, t_sample *const *out)
    {
	mRadiansPerSample = sc_radianspersample();
	mFilterSlope = sc_filterslope();
	mFilterLoops = sc_filterloops();
	mFilterRemain = sc_filterremain();
    }

    void m_set_freq(float f)
    {
	m_freq=f;
	changed = true;
    }

    void m_set_rq(float f)
    {
	m_reson=f;
	changed = true;
    }

private:
    float m_y1, m_y2, m_a0, m_b1, m_b2, m_freq, m_reson;
    bool changed;
    float mRadiansPerSample, mFilterSlope;
    int mFilterLoops, mFilterRemain; 

    FLEXT_CALLBACK_F(m_set_freq);
    FLEXT_CALLBACK_F(m_set_rq);
};

FLEXT_LIB_DSP_V("RLPF~",RLPF_ar);

RLPF_ar::RLPF_ar(int argc, t_atom *argv)
{
    FLEXT_ADDMETHOD_(0,"kfreq",m_set_freq);
    FLEXT_ADDMETHOD_(0,"rq",m_set_rq);

    //parse arguments
    AtomList Args(argc,argv);

    m_freq = sc_getfloatarg(Args,0);
    m_reson = sc_getfloatarg(Args,1);
    changed = true;

    AddOutSignal();

    m_a0 = 0.f;
    m_b1 = 0.f;
    m_b2 = 0.f;
    m_y1 = 0.f;
    m_y2 = 0.f;
}

void RLPF_ar::m_signal(int n, t_sample *const *in, 
			  t_sample *const *out)
{
    t_sample *nin = *in;
    t_sample *nout = *out;

    float y0;
    float y1 = m_y1;
    float y2 = m_y2;
    float a0 = m_a0;
    float b1 = m_b1;
    float b2 = m_b2;

    if (changed)
    {
	float qres = sc_max(0.001, m_reson);
	float pfreq = m_freq * mRadiansPerSample;

	float D = tan(pfreq * qres * 0.5);
	float C = ((1.f-D)/(1.f+D));
	float cosf = cos(pfreq);

	float next_b1 = (1.f + C) * cosf;	
	float next_b2 = -C;
	float next_a0 = (1.f + C - next_b1) * .25;

	float a0_slope = (next_a0 - a0) * mFilterSlope;
	float b1_slope = (next_b1 - b1) * mFilterSlope;
	float b2_slope = (next_b2 - b2) * mFilterSlope;

	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 + 2.f * y1 + y2;

	    y2 = a0 * ZXP(nin) + b1 * y0 + b2 * y1;
	    ZXP(nout) = y2 + 2.f * y0 + y1;

	    y1 = a0 * ZXP(nin) + b1 * y2 + b2 * y0;
	    ZXP(nout) = y1 + 2.f * y2 + y0;

	    a0 += a0_slope; 
	    b1 += b1_slope; 
	    b2 += b2_slope;
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 + 2.f * y1 + y2;
	    y2 = y1; 
	    y1 = y0;
	}

	m_a0 = a0;
	m_b1 = b1;
	m_b2 = b2;
	changed = false;
    }
    else
    {
	for (int i = 0; i!= mFilterLoops;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 + 2.f * y1 + y2;

	    y2 = a0 * ZXP(nin) + b1 * y0 + b2 * y1;
	    ZXP(nout) = y2 + 2.f * y0 + y1;

	    y1 = a0 * ZXP(nin) + b1 * y2 + b2 * y0;
	    ZXP(nout) = y1 + 2.f * y2 + y0;
	}

	for (int i = 0; i!= mFilterRemain;++i)
	{
	    y0 = a0 * ZXP(nin) + b1 * y1 + b2 * y2;
	    ZXP(nout) = y0 + 2.f * y1 + y2;
	    y2 = y1;
	    y1 = y0;
	}
    }
    m_y1 = zapgremlins(y1);
    m_y2 = zapgremlins(y2);
}

/* no control rate RLPF filter */