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-rw-r--r--iemlib2/src/LFO_noise~.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/iemlib2/src/LFO_noise~.c b/iemlib2/src/LFO_noise~.c
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+++ b/iemlib2/src/LFO_noise~.c
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+/* For information on usage and redistribution, and for a DISCLAIMER OF ALL
+* WARRANTIES, see the file, "LICENSE.txt," in this distribution.
+
+iemlib2 written by Thomas Musil, Copyright (c) IEM KUG Graz Austria 2000 - 2006 */
+
+
+#include "m_pd.h"
+#include "iemlib.h"
+
+
+/* -------------------- LFO_noise~ --------------------- */
+/* ---- outputs a 2 point interpolated white noise ----- */
+/* -- with lower cutoff frequency than 0.5 samplerate -- */
+
+static t_class *LFO_noise_tilde_class;
+
+typedef struct _LFO_noise_tilde
+{
+ t_object x_obj;
+ double x_range;
+ double x_rcp_range;
+ unsigned int x_state;
+ t_float x_fact;
+ t_float x_incr;
+ t_float x_y1;
+ t_float x_y2;
+ t_float x_phase;
+} t_LFO_noise_tilde;
+
+static int LFO_noise_tilde_makeseed(void)
+{
+ static unsigned int LFO_noise_tilde_nextseed = 1489853723;
+
+ LFO_noise_tilde_nextseed = LFO_noise_tilde_nextseed * 435898247 + 938284287;
+ return(LFO_noise_tilde_nextseed & 0x7fffffff);
+}
+
+static float LFO_noise_tilde_new_rand(t_LFO_noise_tilde *x)
+{
+ unsigned int state = x->x_state;
+ double new_val, range = x->x_range;
+
+ x->x_state = state = state * 472940017 + 832416023;
+ new_val = range * ((double)state) * (1./4294967296.);
+ if(new_val >= range)
+ new_val = range-1;
+ new_val -= 32767.0;
+ return(new_val*(1.0/32767.0));
+}
+
+static void *LFO_noise_tilde_new(t_float freq)
+{
+ t_LFO_noise_tilde *x = (t_LFO_noise_tilde *)pd_new(LFO_noise_tilde_class);
+
+ x->x_range = 65535.0;
+ x->x_rcp_range = (double)x->x_range * (1.0/4294967296.0);
+ x->x_state = LFO_noise_tilde_makeseed();
+ x->x_fact = 2.0f / 44100.0f;
+ x->x_incr = freq * x->x_fact;
+ if(x->x_incr < 0.0f)
+ x->x_incr = 0.0f;
+ else if(x->x_incr > 0.1f)
+ x->x_incr = 0.1f;
+ x->x_y1 = LFO_noise_tilde_new_rand(x);
+ x->x_y2 = LFO_noise_tilde_new_rand(x);
+ x->x_phase = 0.0f;
+ outlet_new(&x->x_obj, gensym("signal"));
+ return (x);
+}
+
+static t_int *LFO_noise_tilde_perform(t_int *w)
+{
+ t_float *out = (t_float *)(w[1]);
+ t_LFO_noise_tilde *x = (t_LFO_noise_tilde *)(w[2]);
+ int n = (int)(w[3]);
+ t_float phase = x->x_phase;
+ t_float x_y1 = x->x_y1;
+ t_float x_y2 = x->x_y2;
+ t_float incr = x->x_incr;
+
+ while(n--)
+ {
+ if(phase > 1.0f)
+ {
+ x_y1 = x_y2;
+ x_y2 = LFO_noise_tilde_new_rand(x);
+ phase -= 1.0;
+ }
+ *out++ = (x_y2 - x_y1) * phase + x_y1;
+ phase += incr;
+ }
+ x->x_phase = phase;
+ x->x_y1 = x_y1;
+ x->x_y2 = x_y2;
+ return (w+4);
+}
+
+static void LFO_noise_tilde_float(t_LFO_noise_tilde *x, t_floatarg freq)
+{
+ x->x_incr = freq * x->x_fact;
+ if(x->x_incr < 0.0f)
+ x->x_incr = 0.0f;
+ else if(x->x_incr > 0.1f)
+ x->x_incr = 0.1f;
+}
+
+static void LFO_noise_tilde_dsp(t_LFO_noise_tilde *x, t_signal **sp)
+{
+ x->x_fact = 2.0f / sp[0]->s_sr;
+ dsp_add(LFO_noise_tilde_perform, 3, sp[0]->s_vec, x, sp[0]->s_n);
+}
+
+void LFO_noise_tilde_setup(void)
+{
+ LFO_noise_tilde_class = class_new(gensym("LFO_noise~"),
+ (t_newmethod)LFO_noise_tilde_new, 0,
+ sizeof(t_LFO_noise_tilde), 0, A_DEFFLOAT, 0);
+ class_addmethod(LFO_noise_tilde_class, (t_method)LFO_noise_tilde_dsp,
+ gensym("dsp"), 0);
+ class_addfloat(LFO_noise_tilde_class, (t_method)LFO_noise_tilde_float);
+// class_sethelpsymbol(LFO_noise_tilde_class, gensym("iemhelp/help-LFO_noise~"));
+}