lag

svn path=/trunk/externals/tb/; revision=1905

6 files changed, 147 insertions, 5 deletions

diff --git a/sc4pd/make-files.txt b/sc4pd/make-files.txt
index 5a2aaf7..922e05c 100755
--- a/sc4pd/make-files.txt
+++ b/sc4pd/make-files.txt
@@ -9,4 +9,4 @@ SRCS= \
 	Logistic.cpp Latoocarfian.cpp LinCong.cpp amclip.cpp scaleneg.cpp \
 	excess.cpp hypot.cpp ring1.cpp ring2.cpp ring3.cpp ring4.cpp \
 	difsqr.cpp sumsqr.cpp sqrdif.cpp sqrsum.cpp absdif.cpp LFSaw.cpp \
-	LFPulse.cpp Impulse.cpp Integrator.cpp Decay.cpp Decay2.cpp
\ No newline at end of file
+	LFPulse.cpp Impulse.cpp Integrator.cpp Decay.cpp Decay2.cpp Lag.cpp 
\ No newline at end of file
diff --git a/sc4pd/pd/lag.pd b/sc4pd/pd/lag.pd
new file mode 100644
index 0000000..206a07b
--- /dev/null
+++ b/sc4pd/pd/lag.pd
@@ -0,0 +1,17 @@
+#N canvas 0 0 450 300 10;
+#X obj 159 205 dac~;
+#X obj 239 198 print~;
+#X obj 244 171 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
+-1;
+#X obj 257 82 hsl 128 15 1e-04 1 1 0 empty empty empty -2 -6 0 8 -262144
+-1 -1 0 0;
+#X msg 254 102 lagTime \$1;
+#X obj 155 61 WhiteNoise~;
+#X obj 156 130 Lag~ 0.0004;
+#X connect 2 0 1 0;
+#X connect 3 0 4 0;
+#X connect 4 0 6 0;
+#X connect 5 0 6 0;
+#X connect 6 0 0 0;
+#X connect 6 0 0 1;
+#X connect 6 0 1 0;
diff --git a/sc4pd/source/Decay2.cpp b/sc4pd/source/Decay2.cpp
index 557f057..001eb31 100644
--- a/sc4pd/source/Decay2.cpp
+++ b/sc4pd/source/Decay2.cpp
@@ -146,6 +146,7 @@ void Decay2_ar::m_dsp(int n, t_sample *const *in, t_sample *const *out)
 					   (m_decayTime * Samplerate()));
     m_b1b = m_attackTime == 0.f ? 0.f : exp(log001 / 
 					    (m_attackTime * Samplerate()));
+    changed = false;
 }
 
 /* todo: does it make sense to implement a message-based Decay2? 
diff --git a/sc4pd/source/Lag.cpp b/sc4pd/source/Lag.cpp
new file mode 100644
index 0000000..81482a8
--- /dev/null
+++ b/sc4pd/source/Lag.cpp
@@ -0,0 +1,124 @@
+/* sc4pd 
+   Lag~, Lag
+
+   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: Live from the Vision Festival
+   
+*/
+
+#include "sc4pd.hpp"
+
+/* ------------------------ Lag~ -----------------------------*/
+
+class Lag_ar
+    :public flext_dsp
+{
+    FLEXT_HEADER(Lag_ar,flext_dsp);
+
+public:
+    Lag_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);
+    void m_set(float f);
+
+private:
+    FLEXT_CALLBACK_F(m_set);
+    float m_b1, n_b1;
+    float m_y1;
+    float m_lag;
+    bool changed;
+};
+
+FLEXT_LIB_DSP_V("Lag~",Lag_ar);
+
+Lag_ar::Lag_ar(int argc,t_atom * argv)
+{
+    FLEXT_ADDMETHOD_(0,"lagTime",m_set);
+
+    AtomList Args(argc,argv);
+
+    m_lag = sc_getfloatarg(Args,0);
+
+    AddOutSignal();
+
+    m_y1 = 0.f;
+}
+
+void Lag_ar::m_dsp(int n, t_sample *const *in, 
+		   t_sample *const *out)
+{
+    changed = false;
+    m_b1 = m_lag == 0.f ? 0.f : exp(log001 / (m_lag * Samplerate()));
+}
+
+void Lag_ar::m_signal(int n, t_sample *const *in, 
+		      t_sample *const *out)
+{
+    t_sample *nout = *out;
+    t_sample *nin = *in;
+
+    float y1 = m_y1;
+    float b1 = m_b1;
+
+    if (changed)
+    {
+	float b1_slope = CALCSLOPE(m_b1, n_b1);
+	m_b1 = n_b1;
+	for (int i = 0; i!= n;++i)
+	{
+	    float y0 = ZXP(nin); 
+	    ZXP(nout) = y1 = y0 + b1 * (y1 - y0);
+	    b1 += b1_slope;
+	}
+	changed = false;
+    }
+    else
+    {
+	for (int i = 0; i!= n;++i)
+	{
+	    float y0 = ZXP(nin); 
+	    ZXP(nout) = y1 = y0 + b1 * (y1 - y0);
+	}
+    }
+    m_y1 = zapgremlins(y1);
+}
+    
+void Lag_ar::m_set(float f)
+{
+    m_lag = f;
+    n_b1 = m_lag == 0.f ? 0.f : exp(log001 / (m_lag * Samplerate()));
+    changed = true;
+}
+
+/* todo: does a control rate Lag make sense? */
diff --git a/sc4pd/source/main.cpp b/sc4pd/source/main.cpp
index 1f76f4c..681c165 100644
--- a/sc4pd/source/main.cpp
+++ b/sc4pd/source/main.cpp
@@ -58,7 +58,7 @@ void sc4pd_library_setup()
 	 "          ring2(~), ring3(~), ring4(~), difsqr(~), sumsqr(~), "
 	 "sqrdif(~),\n"
 	 "          sqrsum(~), absdif(~), LFSaw(~), LFPulse(~), Impulse(~),\n"
-	 "          Integrator(~), Decay~, Decay2~\n"
+	 "          Integrator(~), Decay~, Decay2~, Lag~\n"
 	 );
 
     //initialize objects
@@ -196,6 +196,8 @@ void sc4pd_library_setup()
     FLEXT_DSP_SETUP(Decay_ar); 
 
     FLEXT_DSP_SETUP(Decay2_ar); 
+
+    FLEXT_DSP_SETUP(Lag_ar); 
 }
 
 FLEXT_LIB_SETUP(sc4pd,sc4pd_library_setup);
diff --git a/sc4pd/source/sc4pd.hpp b/sc4pd/source/sc4pd.hpp
index 214b80c..d26e09e 100644
--- a/sc4pd/source/sc4pd.hpp
+++ b/sc4pd/source/sc4pd.hpp
@@ -48,9 +48,7 @@
 // calculate a slope for control rate interpolation to audio rate.
 //#define CALCSLOPE(next,prev) ((next - prev) * unit->mRate->mSlopeFactor)
 #undef CALCSLOPE
-#define CALCSLOPE(next,prev) ((next - prev) * 1/Blocksize())
-
-
+#define CALCSLOPE(next,prev) ((next - prev) * 1/ Blocksize())
 
 
 /* to make sure the behaviour is consistent: */