This commit was generated by cvs2svn to compensate for changes in r232,

which included commits to RCS files with non-trunk default branches.

svn path=/trunk/; revision=233

1 files changed, 20 insertions, 2 deletions

diff --git a/pd/doc/6.externs/dspobj~.c b/pd/doc/6.externs/dspobj~.c
index a8841f21..5c3fa86b 100644
--- a/pd/doc/6.externs/dspobj~.c
+++ b/pd/doc/6.externs/dspobj~.c
@@ -12,9 +12,16 @@ static t_class *dspobj_class;
 
 typedef struct _dspobj
 {
-    t_object x_obj;
+    t_object x_obj; 	/* obligatory header */
+    t_float x_f;    	/* place to hold inlet's value if it's set by message */
 } t_dspobj;
 
+    /* this is the actual performance routine which acts on the samples.
+    It's called with a single pointer "w" which is our location in the
+    DSP call list.  We return a new "w" which will point to the next item
+    after us.  Meanwhile, w[0] is just a pointer to dsp-perform itself
+    (no use to us), w[1] and w[2] are the input and output vector locations,
+    and w[3] is the number of points to calculate. */
 static t_int *dspobj_perform(t_int *w)
 {
     t_float *in = (t_float *)(w[1]);
@@ -28,6 +35,9 @@ static t_int *dspobj_perform(t_int *w)
     return (w+4);
 }
 
+    /* called to start DSP.  Here we call Pd back to add our perform
+    routine to a linear callback list which Pd in turn calls to grind
+    out the samples. */
 static void dspobj_dsp(t_dspobj *x, t_signal **sp)
 {
     dsp_add(dspobj_perform, 3, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);
@@ -37,13 +47,21 @@ static void *dspobj_new(void)
 {
     t_dspobj *x = (t_dspobj *)pd_new(dspobj_class);
     outlet_new(&x->x_obj, gensym("signal"));
+    x->x_f = 0;
     return (x);
 }
 
+    /* this routine, which must have exactly this name (with the "~" replaced
+    by "_tilde) is called when the code is first loaded, and tells Pd how
+    to build the "class". */
 void dspobj_tilde_setup(void)
 {
     dspobj_class = class_new(gensym("dspobj~"), (t_newmethod)dspobj_new, 0,
     	sizeof(t_dspobj), 0, A_DEFFLOAT, 0);
-    class_addmethod(dspobj_class, nullfn, gensym("signal"), 0);
+	    /* this is magic to declare that the leftmost, "main" inlet
+	    takes signals; other signal inlets are done differently... */
+    CLASS_MAINSIGNALIN(dspobj_class, t_dspobj, x_f);
+    	/* here we tell Pd about the "dsp" method, which is called back
+	when DSP is turned on. */
     class_addmethod(dspobj_class, (t_method)dspobj_dsp, gensym("dsp"), 0);
 }