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-rw-r--r--iemlib1/src/iem_sqrt4~.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/iemlib1/src/iem_sqrt4~.c b/iemlib1/src/iem_sqrt4~.c
new file mode 100644
index 0000000..78b4ef6
--- /dev/null
+++ b/iemlib1/src/iem_sqrt4~.c
@@ -0,0 +1,108 @@
+/* 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 - 2006 */
+
+#include "m_pd.h"
+#include "iemlib.h"
+#include <math.h>
+
+#define IEMSQRT4TAB1SIZE 256
+#define IEMSQRT4TAB2SIZE 1024
+
+/* ------------------------ iem_sqrt4~ ----------------------------- */
+
+t_float *iem_sqrt4_tilde_exptab=(t_float *)0L;
+t_float *iem_sqrt4_tilde_mantissatab=(t_float *)0L;
+
+static t_class *iem_sqrt4_tilde_class;
+
+typedef struct _iem_sqrt4_tilde
+{
+ t_object x_obj;
+ t_float x_msi;
+} t_iem_sqrt4_tilde;
+
+static t_int *iem_sqrt4_tilde_perform(t_int *w)
+{
+ t_float *in = (t_float *)(w[1]);
+ t_float *out = (t_float *)(w[2]);
+ t_int n = (t_int)(w[3])/4;
+
+ while(n--)
+ {
+ t_float f = *in;
+ t_float g, h;
+ long l = *(long *)(in);
+
+ if(f < 0.0f)
+ {
+ *out++ = 0.0f;
+ *out++ = 0.0f;
+ *out++ = 0.0f;
+ *out++ = 0.0f;
+ }
+ else
+ {
+ g = iem_sqrt4_tilde_exptab[(l >> 23) & 0xff] * iem_sqrt4_tilde_mantissatab[(l >> 13) & 0x3ff];
+ h = f * (1.5f * g - 0.5f * g * g * g * f);
+ *out++ = h;
+ *out++ = h;
+ *out++ = h;
+ *out++ = h;
+ }
+ in += 4;
+ }
+ return(w+4);
+}
+
+static void iem_sqrt4_tilde_dsp(t_iem_sqrt4_tilde *x, t_signal **sp)
+{
+ dsp_add(iem_sqrt4_tilde_perform, 3, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);
+}
+
+static void iem_sqrt4_tilde_maketable(void)
+{
+ int i;
+ t_float f;
+ long l;
+
+ if(!iem_sqrt4_tilde_exptab)
+ {
+ iem_sqrt4_tilde_exptab = (t_float *)getbytes(sizeof(t_float) * IEMSQRT4TAB1SIZE);
+ for(i=0; i<IEMSQRT4TAB1SIZE; i++)
+ {
+ l = (i ? (i == IEMSQRT4TAB1SIZE-1 ? IEMSQRT4TAB1SIZE-2 : i) : 1)<< 23;
+ *(long *)(&f) = l;
+ iem_sqrt4_tilde_exptab[i] = 1.0f/sqrt(f);
+ }
+ }
+ if(!iem_sqrt4_tilde_mantissatab)
+ {
+ iem_sqrt4_tilde_mantissatab = (t_float *)getbytes(sizeof(t_float) * IEMSQRT4TAB2SIZE);
+ for(i=0; i<IEMSQRT4TAB2SIZE; i++)
+ {
+ f = 1.0f + (1.0f/(t_float)IEMSQRT4TAB2SIZE) * (t_float)i;
+ iem_sqrt4_tilde_mantissatab[i] = 1.0f/sqrt(f);
+ }
+ }
+}
+
+static void *iem_sqrt4_tilde_new(void)
+{
+ t_iem_sqrt4_tilde *x = (t_iem_sqrt4_tilde *)pd_new(iem_sqrt4_tilde_class);
+
+ outlet_new(&x->x_obj, gensym("signal"));
+ x->x_msi = 0;
+ return (x);
+}
+
+void iem_sqrt4_tilde_setup(void)
+{
+ iem_sqrt4_tilde_class = class_new(gensym("iem_sqrt4~"), (t_newmethod)iem_sqrt4_tilde_new, 0,
+ sizeof(t_iem_sqrt4_tilde), 0, 0);
+ CLASS_MAINSIGNALIN(iem_sqrt4_tilde_class, t_iem_sqrt4_tilde, x_msi);
+ class_addmethod(iem_sqrt4_tilde_class, (t_method)iem_sqrt4_tilde_dsp, gensym("dsp"), 0);
+ iem_sqrt4_tilde_maketable();
+// class_sethelpsymbol(iem_sqrt4_tilde_class, gensym("iemhelp/help-iem_sqrt4~"));
+}