renamed *_tilde.c-files to *~.c

svn path=/trunk/externals/zexy/; revision=2998

1 files changed, 167 insertions, 0 deletions

diff --git a/src/noisi~.c b/src/noisi~.c
new file mode 100644
index 0000000..14fb1be
--- /dev/null
+++ b/src/noisi~.c
@@ -0,0 +1,167 @@
+/******************************************************
+ *
+ * zexy - implementation file
+ *
+ * copyleft (c) IOhannes m zmölnig
+ *
+ *   1999:forum::für::umläute:2004
+ *
+ *   institute of electronic music and acoustics (iem)
+ *
+ ******************************************************
+ *
+ * license: GNU General Public License v.2
+ *
+ ******************************************************/
+
+/*
+  30041999
+
+  two bandlimited noise gnerators based on DODGE/JERSE "computer music" c3.9 : RANDI & RANDH 
+	
+  I do not care for copyrights
+  (all in all, the used noise~-code (in fact, the pseude-random-code) is from Miller Puckette 
+  and I made only very few modifications so look out for the LICENSE.TXT delivered with 
+  puredata for further (c)-information
+
+  forum für umläute 1999
+
+  this is in fact the very same as the late "NOISE.C", except that I tried to optimize the code a little  bit
+  (by partially removing those very expensive if..then's in about 15 minutes, so there are thousands of new bugs very likely)
+
+  14071999
+  finally added changing seeds, this is to prevent to noise~-units to output the very same, something quite unnatural even for pseudo-random-noise
+*/
+
+#include "zexy.h"
+
+/* general */
+
+typedef struct _nois
+{
+  t_object x_obj;
+  int val;
+  t_float current;
+  t_float decrement;
+  t_float updater;		
+  t_float to_go;
+} t_nois;
+
+
+static void set_noisfreq(t_nois *x, t_floatarg freq)
+{
+  x->updater = (freq > 0) ? sys_getsr() / freq : 1;
+  if (x->updater < 1)
+    {
+      x->updater = 1;
+    }
+  x->to_go = 0;
+}
+
+/* ------------------------ noisi~ ----------------------------- */ 
+
+static t_class *noisi_class;
+
+static t_int *noisi_perform(t_int *w){
+  t_nois *x = (t_nois *)(w[1]);
+  t_float *out = (t_float *)(w[2]);
+  int n = (int)(w[3]);
+
+  int *vp = (int *)(&x->val); /* what the ... */ 
+  int i_value = *vp;
+  t_float f_value = x->current;
+  t_float decrement = x->decrement;
+  t_float all_to_go = x->updater;
+  t_float still_to_go = x->to_go;
+
+  if (all_to_go == 1)	{
+    /* this is "pure white" noise, so we have to calculate each sample */ 
+    while (n--) {
+      i_value *= 435898247;
+      i_value += 382842987;
+      *out++ = ((t_sample)((i_value & 0x7fffffff) - 0x40000000)) * (t_sample)(1.0 / 0x40000000);
+    }
+  }  else if (n < still_to_go)   {
+    /* signal won't change for the next 64 samples */ 
+    still_to_go -= n;
+    while (n--){
+      *out++ = (f_value -= decrement);
+    }
+  }  else if (all_to_go + still_to_go > n) {
+    /* only one update calculation necessary for 64 samples !!! */ 
+    while (still_to_go-- > 0)	{
+      n--;
+      *out++ = (f_value -= decrement);
+    }
+    still_to_go += all_to_go + 1;
+    decrement = (
+		 (f_value = 
+		  ((t_sample)((i_value & 0x7fffffff)-0x40000000))*(t_sample)(1.0 / 0x40000000)) -
+		 ((t_sample)(((i_value = i_value * 435898247 + 382842987) & 0x7fffffff)
+			  - 0x40000000)) * (t_sample)(1.0 / 0x40000000)
+		 )  / all_to_go;
+
+    while (n--)	{
+      still_to_go--;
+      *out++ = (f_value -= decrement);
+    }
+  }  else {
+    /* anything else */ 
+    while (n--)	{
+      if (still_to_go-- <= 0) {		/* update only if all time has elapsed */ 
+	still_to_go += all_to_go;
+	decrement = (
+		     (f_value = ((t_sample)((i_value & 0x7fffffff) - 0x40000000)) * (t_sample)(1.0 / 0x40000000)) -
+		     ((t_sample)(((i_value = i_value * 435898247 + 382842987) & 0x7fffffff) - 0x40000000)) * (t_sample)(1.0 / 0x40000000)
+		     ) / all_to_go;
+      }
+      *out++ = (f_value -= decrement);
+    }
+  }
+
+  *vp = i_value;
+  x->current = f_value;
+  x->decrement = decrement;
+  x->to_go = still_to_go;
+  
+  return (w+4);
+}
+
+static void noisi_dsp(t_nois *x, t_signal **sp){
+  dsp_add(noisi_perform, 3, x, sp[0]->s_vec, sp[0]->s_n);
+}
+
+
+static void noisi_helper(void){
+  post("\n%c noisi~\t:: a bandlimited interpolating pseudo-noise generator", HEARTSYMBOL);
+  post("<freq>\t : sampling-frequency (in Hz)\n"
+       "'help'\t : view this");
+  post("creation : \"noisi~ [<freq>]\"\t: ('0'(default) will produce 'white' noise)\n");
+  post("note\t : the seed of the pseudo-noise generator changes from\n"
+       "\t     instance to instance, so two noisi~-objects created at the\n"
+       "\t     same time will produce different signals, something the original\n"
+       "\t     noise~-object misses\n");
+  post("for further details see DODGE/JERSE \"computer music\" c3.9\n");
+}
+
+static void *noisi_new(t_floatarg f){
+  t_nois *x = (t_nois *)pd_new(noisi_class);
+  
+  static int init = 4259;
+  x->val = (init *= 17);
+
+  set_noisfreq (x, f);
+
+  outlet_new(&x->x_obj, gensym("signal"));
+  return (x);
+}
+
+void noisi_tilde_setup(void){
+  noisi_class = class_new(gensym("noisi~"), (t_newmethod)noisi_new, 0, sizeof(t_nois), 0, A_DEFFLOAT, 0);
+
+  class_addfloat(noisi_class, set_noisfreq);
+  class_addmethod(noisi_class, (t_method)noisi_dsp, gensym("dsp"), 0);
+
+  class_addmethod(noisi_class, (t_method)noisi_helper, gensym("help"), 0);
+  class_sethelpsymbol(noisi_class, gensym("zexy/noisi~"));
+}