1 files changed, 154 insertions, 0 deletions

diff --git a/apps/plugins/pdbox/PDa/intern/sqrt~.c b/apps/plugins/pdbox/PDa/intern/sqrt~.c
new file mode 100644
index 0000000000..5e4b649f8e
--- /dev/null
+++ b/apps/plugins/pdbox/PDa/intern/sqrt~.c
@@ -0,0 +1,154 @@
+#define DUMTAB1SIZE 256
+#define DUMTAB2SIZE 1024
+
+#include<m_pd.h>
+#include<m_fixed.h>
+
+/* sigsqrt -  square root good to 8 mantissa bits  */
+
+static float rsqrt_exptab[DUMTAB1SIZE], rsqrt_mantissatab[DUMTAB2SIZE];
+
+static void init_rsqrt(void)
+{
+    int i;
+    for (i = 0; i < DUMTAB1SIZE; i++)
+    {
+        float f;
+        long l = (i ? (i == DUMTAB1SIZE-1 ? DUMTAB1SIZE-2 : i) : 1)<< 23;
+        *(long *)(&f) = l;
+        rsqrt_exptab[i] = 1./sqrt(f);   
+    }
+    for (i = 0; i < DUMTAB2SIZE; i++)
+    {
+        float f = 1 + (1./DUMTAB2SIZE) * i;
+        rsqrt_mantissatab[i] = 1./sqrt(f);      
+    }
+}
+
+typedef struct sigsqrt
+{
+    t_object x_obj;
+    float x_f;
+} t_sigsqrt;
+
+static t_class *sigsqrt_class;
+
+static void *sigsqrt_new(void)
+{
+    t_sigsqrt *x = (t_sigsqrt *)pd_new(sigsqrt_class);
+    outlet_new(&x->x_obj, gensym("signal"));
+    x->x_f = 0;
+    return (x);
+}
+
+t_int *sigsqrt_perform(t_int *w)    /* not static; also used in d_fft.c */
+{
+    float *in = *(t_float **)(w+1), *out = *(t_float **)(w+2);
+    t_int n = *(t_int *)(w+3);
+    while (n--)
+    {   
+        float f = *in;
+        long l = *(long *)(in++);
+        if (f < 0) *out++ = 0;
+        else
+        {
+            float g = rsqrt_exptab[(l >> 23) & 0xff] *
+                rsqrt_mantissatab[(l >> 13) & 0x3ff];
+            *out++ = f * (1.5 * g - 0.5 * g * g * g * f);
+        }
+    }
+    return (w + 4);
+}
+
+static void sigsqrt_dsp(t_sigsqrt *x, t_signal **sp)
+{
+    dsp_add(sigsqrt_perform, 3, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);
+}
+
+void sqrt_tilde_setup(void)
+{
+    init_rsqrt();
+    sigsqrt_class = class_new(gensym("sqrt~"), (t_newmethod)sigsqrt_new, 0,
+        sizeof(t_sigsqrt), 0, 0);
+    class_addcreator(sigsqrt_new, gensym("q8_sqrt~"), 0);   /* old name */
+    CLASS_MAINSIGNALIN(sigsqrt_class, t_sigsqrt, x_f);
+    class_addmethod(sigsqrt_class, (t_method)sigsqrt_dsp, gensym("dsp"), 0);
+}
+
+#define DUMTAB1SIZE 256
+#define DUMTAB2SIZE 1024
+
+#include<m_pd.h>
+#include<m_fixed.h>
+
+/* sigsqrt -  square root good to 8 mantissa bits  */
+
+static float rsqrt_exptab[DUMTAB1SIZE], rsqrt_mantissatab[DUMTAB2SIZE];
+
+static void init_rsqrt(void)
+{
+    int i;
+    for (i = 0; i < DUMTAB1SIZE; i++)
+    {
+        float f;
+        long l = (i ? (i == DUMTAB1SIZE-1 ? DUMTAB1SIZE-2 : i) : 1)<< 23;
+        *(long *)(&f) = l;
+        rsqrt_exptab[i] = 1./sqrt(f);   
+    }
+    for (i = 0; i < DUMTAB2SIZE; i++)
+    {
+        float f = 1 + (1./DUMTAB2SIZE) * i;
+        rsqrt_mantissatab[i] = 1./sqrt(f);      
+    }
+}
+
+typedef struct sigsqrt
+{
+    t_object x_obj;
+    float x_f;
+} t_sigsqrt;
+
+static t_class *sigsqrt_class;
+
+static void *sigsqrt_new(void)
+{
+    t_sigsqrt *x = (t_sigsqrt *)pd_new(sigsqrt_class);
+    outlet_new(&x->x_obj, gensym("signal"));
+    x->x_f = 0;
+    return (x);
+}
+
+t_int *sigsqrt_perform(t_int *w)    /* not static; also used in d_fft.c */
+{
+    float *in = *(t_float **)(w+1), *out = *(t_float **)(w+2);
+    t_int n = *(t_int *)(w+3);
+    while (n--)
+    {   
+        float f = *in;
+        long l = *(long *)(in++);
+        if (f < 0) *out++ = 0;
+        else
+        {
+            float g = rsqrt_exptab[(l >> 23) & 0xff] *
+                rsqrt_mantissatab[(l >> 13) & 0x3ff];
+            *out++ = f * (1.5 * g - 0.5 * g * g * g * f);
+        }
+    }
+    return (w + 4);
+}
+
+static void sigsqrt_dsp(t_sigsqrt *x, t_signal **sp)
+{
+    dsp_add(sigsqrt_perform, 3, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);
+}
+
+void sqrt_tilde_setup(void)
+{
+    init_rsqrt();
+    sigsqrt_class = class_new(gensym("sqrt~"), (t_newmethod)sigsqrt_new, 0,
+        sizeof(t_sigsqrt), 0, 0);
+    class_addcreator(sigsqrt_new, gensym("q8_sqrt~"), 0);   /* old name */
+    CLASS_MAINSIGNALIN(sigsqrt_class, t_sigsqrt, x_f);
+    class_addmethod(sigsqrt_class, (t_method)sigsqrt_dsp, gensym("dsp"), 0);
+}
+