From 577ac6e80ff4f436fbd054291ed7dddbc31bd49a Mon Sep 17 00:00:00 2001
From: Hans-Christoph Steiner <eighthave@users.sourceforge.net>
Date: Tue, 18 May 2004 21:33:33 +0000
Subject: This commit was generated by cvs2svn to compensate for changes in
 r1738, which included commits to RCS files with non-trunk default branches.

svn path=/trunk/externals/iemlib/; revision=1739
---
 src/iemlib1/siglp1_t.c | 219 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 219 insertions(+)
 create mode 100644 src/iemlib1/siglp1_t.c

(limited to 'src/iemlib1/siglp1_t.c')

diff --git a/src/iemlib1/siglp1_t.c b/src/iemlib1/siglp1_t.c
new file mode 100644
index 0000000..060d988
--- /dev/null
+++ b/src/iemlib1/siglp1_t.c
@@ -0,0 +1,219 @@
+/* For information on usage and redistribution, and for a DISCLAIMER OF ALL
+* WARRANTIES, see the file, "LICENSE.txt," in this distribution.
+
+iemlib1 written by Thomas Musil, Copyright (c) IEM KUG Graz Austria 2000 - 2003 */
+
+#ifdef NT
+#pragma warning( disable : 4244 )
+#pragma warning( disable : 4305 )
+#endif
+
+
+#include "m_pd.h"
+#include "iemlib.h"
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+
+
+/* -- lp1_t~ - slow dynamic lowpass-filter 1. order with tau input --- */
+
+typedef struct siglp1_t
+{
+	t_object x_obj;
+	float	yn1;
+	float	c0;
+	float	c1;
+	float	sr;
+	float	cur_t;
+	float	delta_t;
+	float	end_t;
+	float	ticks_per_interpol_time;
+	float	rcp_ticks;
+	float	interpol_time;
+	int	  ticks;
+	int	  counter_t;
+	float	x_msi;
+} t_siglp1_t;
+
+t_class *siglp1_t_class;
+
+static void siglp1_t_dsp_tick(t_siglp1_t *x)
+{
+	if(x->counter_t)
+	{
+		if(x->counter_t <= 1)
+		{
+			x->cur_t = x->end_t;
+			x->counter_t = 0;
+		}
+		else
+		{
+			x->counter_t--;
+			x->cur_t += x->delta_t;
+		}
+		if(x->cur_t == 0.0f)
+			x->c1 = 0.0f;
+		else
+			x->c1 = exp((x->sr)/x->cur_t);
+		x->c0 = 1.0f - x->c1;
+	}
+}
+
+static t_int *siglp1_t_perform(t_int *w)
+{
+	float *in = (float *)(w[1]);
+	float *out = (float *)(w[2]);
+	t_siglp1_t *x = (t_siglp1_t *)(w[3]);
+	int i, n = (t_int)(w[4]);
+	float yn0, yn1=x->yn1;
+	float c0=x->c0, c1=x->c1;
+
+	siglp1_t_dsp_tick(x);
+	for(i=0; i<n; i++)
+	{
+		yn0 = (*in++)*c0 + yn1*c1;
+		*out++ = yn0;
+		yn1 = yn0;
+	}
+	/* NAN protect */
+	if(PD_BADFLOAT(yn1))
+		yn1 = 0.0f;
+	x->yn1 = yn1;
+	return(w+5);
+}
+
+static t_int *siglp1_t_perf8(t_int *w)
+{
+	float *in = (float *)(w[1]);
+	float *out = (float *)(w[2]);
+	t_siglp1_t *x = (t_siglp1_t *)(w[3]);
+	int i, n = (t_int)(w[4]);
+	float yn[9];
+	float c0=x->c0, c1=x->c1;
+
+	siglp1_t_dsp_tick(x);
+	yn[0] = x->yn1;
+	for(i=0; i<n; i+=8, in+=8, out+=8)
+	{
+		yn[1] = in[0]*c0 + yn[0]*c1;
+		out[0] = yn[1];
+		yn[2] = in[1]*c0 + yn[1]*c1;
+		out[1] = yn[2];
+		yn[3] = in[2]*c0 + yn[2]*c1;
+		out[2] = yn[3];
+		yn[4] = in[3]*c0 + yn[3]*c1;
+		out[3] = yn[4];
+		yn[5] = in[4]*c0 + yn[4]*c1;
+		out[4] = yn[5];
+		yn[6] = in[5]*c0 + yn[5]*c1;
+		out[5] = yn[6];
+		yn[7] = in[6]*c0 + yn[6]*c1;
+		out[6] = yn[7];
+		yn[8] = in[7]*c0 + yn[7]*c1;
+		out[7] = yn[8];
+		yn[0] = yn[8];
+	}
+	/* NAN protect */
+	if(PD_BADFLOAT(yn[0]))
+		yn[0] = 0.0f;
+
+	x->yn1 = yn[0];
+	return(w+5);
+}
+
+static void siglp1_t_ft2(t_siglp1_t *x, t_floatarg t)
+{
+	int i = (int)((x->ticks_per_interpol_time)*t);
+
+	x->interpol_time = t;
+	if(i <= 0)
+		i = 1;
+	x->ticks = i;
+	x->rcp_ticks = 1.0f / (float)i;
+}
+
+static void siglp1_t_ft1(t_siglp1_t *x, t_floatarg time_const)
+{
+	if(time_const < 0.0f)
+		time_const = 0.0f;
+	if(time_const != x->cur_t)
+	{
+		x->end_t = time_const;
+		x->counter_t = x->ticks;
+		x->delta_t = (time_const - x->cur_t) * x->rcp_ticks;
+	}
+}
+
+static void siglp1_t_dsp(t_siglp1_t *x, t_signal **sp)
+{
+	int i, n=(int)sp[0]->s_n;
+
+	x->sr = -1000.0f / (float)(sp[0]->s_sr);
+	x->ticks_per_interpol_time = 0.001f * (float)(sp[0]->s_sr) / (float)n;
+	i = (int)((x->ticks_per_interpol_time)*(x->interpol_time));
+	if(i <= 0)
+		i = 1;
+	x->ticks = i;
+	x->rcp_ticks = 1.0f / (float)i;
+	if(x->cur_t == 0.0f)
+		x->c1 = 0.0f;
+	else
+		x->c1 = exp((x->sr)/x->cur_t);
+	x->c0 = 1.0f - x->c1;
+	if(n&7)
+		dsp_add(siglp1_t_perform, 4, sp[0]->s_vec, sp[1]->s_vec, x, n);
+	else
+		dsp_add(siglp1_t_perf8, 4, sp[0]->s_vec, sp[1]->s_vec, x, n);
+}
+
+static void *siglp1_t_new(t_symbol *s, int argc, t_atom *argv)
+{
+	t_siglp1_t *x = (t_siglp1_t *)pd_new(siglp1_t_class);
+	int i;
+	float time_const=0.0f, interpol=0.0f;
+
+	inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_float, gensym("ft1"));
+	inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_float, gensym("ft2"));
+	outlet_new(&x->x_obj, &s_signal);
+	x->x_msi = 0;
+	x->counter_t = 1;
+	x->delta_t = 0.0f;
+	x->interpol_time = 0.0f;
+	x->yn1 = 0.0f;
+	x->sr = -1.0f / 44.1f;
+	if((argc >= 1)&&IS_A_FLOAT(argv,0))
+		time_const = (float)atom_getfloatarg(0, argc, argv);
+	if((argc >= 2)&&IS_A_FLOAT(argv,1))
+		interpol = (float)atom_getfloatarg(1, argc, argv);
+	if(time_const < 0.0f)
+		time_const = 0.0f;
+	x->cur_t = time_const;
+	if(time_const == 0.0f)
+		x->c1 = 0.0f;
+	else
+		x->c1 = exp((x->sr)/time_const);
+	x->c0 = 1.0f - x->c1;
+	if(interpol < 0.0f)
+		interpol = 0.0f;
+	x->interpol_time = interpol;
+	x->ticks_per_interpol_time = 0.5f;
+	i = (int)((x->ticks_per_interpol_time)*(x->interpol_time));
+	if(i <= 0)
+		i = 1;
+	x->ticks = i;
+	x->rcp_ticks = 1.0f / (float)i;
+	x->end_t = x->cur_t;
+	return (x);
+}
+
+void siglp1_t_setup(void)
+{
+	siglp1_t_class = class_new(gensym("lp1_t~"), (t_newmethod)siglp1_t_new,
+				0, sizeof(t_siglp1_t), 0, A_GIMME, 0);
+	CLASS_MAINSIGNALIN(siglp1_t_class, t_siglp1_t, x_msi);
+	class_addmethod(siglp1_t_class, (t_method)siglp1_t_dsp, gensym("dsp"), 0);
+	class_addmethod(siglp1_t_class, (t_method)siglp1_t_ft1, gensym("ft1"), A_FLOAT, 0);
+	class_addmethod(siglp1_t_class, (t_method)siglp1_t_ft2, gensym("ft2"), A_FLOAT, 0);
+	class_sethelpsymbol(siglp1_t_class, gensym("iemhelp/help-lp1_t~"));
+}
-- 
cgit v1.2.1