/*
* step~: unity step function
*
* (c) 1999-2011 IOhannes m zmölnig, forum::für::umläute, institute of electronic music and acoustics (iem)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see .
*/
/*
step~ : will make a unity step at a desired point in the signal-vector; the second input specifies a
length: after the so-specified time has elapsed, the step will toggle back to the previous
value;
the length can be passed as an argument when creating the object
with length==1 you might do the dirac~ thing a little bit more complicated
with length==0 the output just toggles between 0 and 1 every time you bang the object
NOTE : the inlets do NOT specify any times but sample-NUMBERS; there are 64 samples in a signal-vector,
each "lasting" for 1/44100 secs.
*/
#include "zexy.h"
/* ------------------------ step~ ----------------------------- */
static t_class *step_class;
typedef struct _step
{
t_object x_obj;
int position;
int length;
int toggle;
int wait4start;
int wait4stop;
} t_step;
static void step_bang(t_step *x)
{
x->wait4stop = x->length + (x->wait4start = x->position);
}
static void step_float(t_step *x, t_float where)
{
x->wait4stop = x->length +
(x->wait4start =
(x->position = (where>0)*where)
);
}
static void step_setlength(t_step *x, t_float arg)
{
x->length = 1 + (arg>0)*arg;
}
static t_int *step_perform(t_int *w)
{
t_step *x = (t_step *)(w[1]);
t_sample *out = (t_sample *)(w[2]);
int n = (int)(w[3]);
int toggle = x->toggle;
int wait4start = x->wait4start, wait4stop = x->wait4stop;
while (n--)
{
wait4stop--;
if (!wait4start--) toggle ^= 1;
else if (!wait4stop) toggle ^= 1;
*out++ = toggle;
}
x->wait4start = wait4start;
x->wait4stop = wait4stop;
x->toggle = toggle;
return (w+4);
}
static void step_dsp(t_step *x, t_signal **sp)
{
dsp_add(step_perform, 3, x, sp[0]->s_vec, sp[0]->s_n);
}
static void step_helper(void)
{
post(""HEARTSYMBOL" step~-object :: generates a unity-step");
post("creation : \"dirac~ [ []]\" : create a rectangular window\n"
"\t\t\tat specified position and with specified length (in samples)\n"
"inlet1\t: \t: create a rectangular window at new position\n"
"\t 'bang'\t: create a rectangular window at specified position\n"
"\t 'help'\t: view this\n"
"inlet2\t: \t: define new window length ('0' will make a unity-step)\n"
"outlet\t: signal~");
}
static void *step_new(t_floatarg farg)
{
t_step *x = (t_step *)pd_new(step_class);
inlet_new(&x->x_obj, &x->x_obj.ob_pd, gensym("float"), gensym("ft1"));
outlet_new(&x->x_obj, gensym("signal"));
x->position = 0;
x->wait4start = x->wait4stop = 0;
x->toggle = 1;
step_setlength(x, farg);
return (x);
}
void step_tilde_setup(void)
{
step_class = class_new(gensym("step~"), (t_newmethod)step_new, 0,
sizeof(t_step), 0, A_DEFFLOAT, 0);
class_addfloat(step_class, step_float);
class_addbang(step_class, step_bang);
class_addmethod(step_class, (t_method)step_setlength, gensym("ft1"), A_FLOAT, 0);
class_addmethod(step_class, (t_method)step_dsp, gensym("dsp"), 0);
class_addmethod(step_class, (t_method)step_helper, gensym("help"), 0);
zexy_register("step~");
}