aboutsummaryrefslogtreecommitdiff
path: root/sc4pd/source/TwoPole.cpp
diff options
context:
space:
mode:
authorIOhannes m zmölnig <zmoelnig@iem.at>2015-10-14 15:14:38 +0200
committerIOhannes m zmölnig <zmoelnig@iem.at>2015-10-14 15:14:38 +0200
commit28b7e464fd119b8c848753a1f41070422c463c41 (patch)
tree07449abdf85d8f1fd4068839b974242b429720ca /sc4pd/source/TwoPole.cpp
parent90c6018a9401e38859f733b3521c919e042322b7 (diff)
parent6932ee2d22511226378218992b0005cb01eb235e (diff)
- abstractions/tb - externals/tb
Diffstat (limited to 'sc4pd/source/TwoPole.cpp')
-rw-r--r--sc4pd/source/TwoPole.cpp167
1 files changed, 167 insertions, 0 deletions
diff --git a/sc4pd/source/TwoPole.cpp b/sc4pd/source/TwoPole.cpp
new file mode 100644
index 0000000..b37d17f
--- /dev/null
+++ b/sc4pd/source/TwoPole.cpp
@@ -0,0 +1,167 @@
+/* sc4pd
+ TwoPole~
+
+ 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: VA: Insight
+
+*/
+
+#include "sc4pd.hpp"
+
+/* ------------------------ TwoPole~ -------------------------------*/
+
+class TwoPole_ar:
+ public sc4pd_dsp
+{
+ FLEXT_HEADER(TwoPole_ar,sc4pd_dsp);
+
+public:
+ TwoPole_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_radius(float f)
+ {
+ m_reson=f;
+ changed = true;
+ }
+
+
+private:
+ float m_b1, m_b2, m_y1, m_y2, m_freq, m_reson;
+ bool changed;
+ float mRadiansPerSample, mFilterSlope;
+ int mFilterLoops, mFilterRemain;
+
+ FLEXT_CALLBACK_F(m_set_freq);
+ FLEXT_CALLBACK_F(m_set_radius);
+};
+
+FLEXT_LIB_DSP_V("TwoPole~",TwoPole_ar);
+
+TwoPole_ar::TwoPole_ar(int argc, t_atom *argv)
+{
+ FLEXT_ADDMETHOD_(0,"kfreq",m_set_freq);
+ FLEXT_ADDMETHOD_(0,"kradius",m_set_radius);
+
+ //parse arguments
+ AtomList Args(argc,argv);
+
+ m_freq = sc_getfloatarg(Args,0);
+ m_reson = sc_getfloatarg(Args,1);
+ changed = false;
+
+ AddOutSignal();
+
+ m_b1 = 0.f;
+ m_b2 = 0.f;
+ m_y1 = 0.f;
+ m_y2 = 0.f;
+}
+
+void TwoPole_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;
+
+ if (changed)
+ {
+ float b1 = m_b1;
+ float b2 = m_b2;
+ float b1_next = 2.f * m_reson * cos(m_freq * mRadiansPerSample);
+ float b2_next = -(m_reson * m_reson);
+ float b1_slope = (b1_next - b1) * mFilterSlope;
+ float b2_slope = (b2_next - b2) * mFilterSlope;
+
+ for (int i = 0; i!= mFilterLoops;++i)
+ {
+ ZXP(nout) = y0 = ZXP(nin) + b1 * y1 + b2 * y2;
+ ZXP(nout) = y2 = ZXP(nin) + b1 * y0 + b2 * y1;
+ ZXP(nout) = y1 = ZXP(nin) + b1 * y2 + b2 * y0;
+
+ b1 += b1_slope;
+ b2 += b2_slope;
+ }
+
+ for (int i = 0; i!= mFilterRemain;++i)
+ {
+ ZXP(nout) = y0 = ZXP(nin) + b1 * y1 + b2 * y2;
+ y2 = y1;
+ y1 = y0;
+ }
+
+ m_b1 = b1;
+ m_b2 = b2;
+ changed = false;
+ }
+ else
+ {
+ float b1 = m_b1;
+ float b2 = m_b2;
+
+ for (int i = 0; i!= mFilterLoops;++i)
+ {
+ ZXP(nout) = y0 = ZXP(nin) + b1 * y1 + b2 * y2;
+ ZXP(nout) = y2 = ZXP(nin) + b1 * y0 + b2 * y1;
+ ZXP(nout) = y1 = ZXP(nin) + b1 * y2 + b2 * y0;
+ }
+ for (int i = 0; i!= mFilterRemain;++i)
+ {
+ ZXP(nout) = y0 = ZXP(nin) + b1 * y1 + b2 * y2;
+ y2 = y1;
+ y1 = y0;
+ }
+ }
+ m_y1 = zapgremlins(y1);
+ m_y2 = zapgremlins(y2);
+}
+
+/* no control rate two pole filter */