As a corrolar, I would like to know why in the pan~ example code of Iohannes's "How to write externals" I can only see declaration of two inlets and after compiling, the creation in Pd of pan~ object appears to have three inlets ??? If somebody can point me out where in this following code is specified the fact that the object has to be instantiated with three inlets, it would be nice.

#include "m_pd.h"

static t_class *pan_tilde_class;

typedef struct _pan_tilde { t_object x_obj; t_sample f_pan; t_sample f; } t_pan_tilde;

t_int *pan_tilde_perform(t_int *w) { t_pan_tilde *x = (t_pan_tilde *)(w[1]); t_sample *in1 = (t_sample *)(w[2]); t_sample *in2 = (t_sample *)(w[3]); t_sample *out = (t_sample *)(w[4]); int n = (int)(w[5]); t_sample f_pan = (x->f_pan<0)?0.0:(x->f_pan>1)?1.0:x->f_pan;

while (n--) *out++ = (*in1++)*(1-f_pan)+(*in2++)*f_pan;

return (w+6); }

void pan_tilde_dsp(t_pan_tilde *x, t_signal **sp) { dsp_add(pan_tilde_perform, 5, x, sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec, sp[0]->s_n); }

void *pan_tilde_new(t_floatarg f) { t_pan_tilde *x = (t_pan_tilde *)pd_new(pan_tilde_class);

x->f_pan = f;

inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal); floatinlet_new (&x->x_obj, &x->f_pan); outlet_new(&x->x_obj, &s_signal);

return (void *)x; }

void pan_tilde_setup(void) { pan_tilde_class = class_new(gensym("pan~"), (t_newmethod)pan_tilde_new, 0, sizeof(t_pan_tilde), CLASS_DEFAULT, A_DEFFLOAT, 0);

class_addmethod(pan_tilde_class, (t_method)pan_tilde_dsp, gensym("dsp"), 0); CLASS_MAINSIGNALIN(pan_tilde_class, t_pan_tilde, f); }