apps/plugins/pdbox/PDa/intern/vcf~.c

   1 #include "../src/m_pd.h"
   2 #include <../src/m_fixed.h>
   3 #include "cos_table.h"
   4
   5 /* ---------------- vcf~ - 2-pole bandpass filter. ----------------- */
   6 /* GG: complex resonator with signal frequency control
   7    this time using the bigger cos_table without interpolation
   8    really have to switch to a separate fixpoint format sometime
   9 */
  10
  11 typedef struct vcfctl
  12 {
  13     t_sample c_re;
  14     t_sample c_im;
  15     t_sample c_q;
  16     t_sample c_isr;
  17 } t_vcfctl;
  18
  19 typedef struct sigvcf
  20 {
  21     t_object x_obj;
  22     t_vcfctl x_cspace;
  23     t_vcfctl *x_ctl;
  24     float x_f;
  25 } t_sigvcf;
  26
  27 t_class *sigvcf_class;
  28
  29 static void *sigvcf_new(t_floatarg q)
  30 {
  31     t_sigvcf *x = (t_sigvcf *)pd_new(sigvcf_class);
  32     inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
  33     inlet_new(&x->x_obj, &x->x_obj.ob_pd, gensym("float"), gensym("ft1"));
  34     outlet_new(&x->x_obj, gensym("signal"));
  35     outlet_new(&x->x_obj, gensym("signal"));
  36     x->x_ctl = &x->x_cspace;
  37     x->x_cspace.c_re = 0;
  38     x->x_cspace.c_im = 0;
  39     x->x_cspace.c_q = ftofix(q);
  40     x->x_cspace.c_isr = 0;
  41     x->x_f = 0;
  42     return (x);
  43 }
  44
  45 static void sigvcf_ft1(t_sigvcf *x, t_floatarg f)
  46 {
  47     x->x_ctl->c_q = (f > 0 ? ftofix(f) : 0);
  48 }
  49
  50 static t_int *sigvcf_perform(t_int *w)
  51 {
  52     t_sample *in1 = (t_sample *)(w[1]);
  53     t_sample *in2 = (t_sample *)(w[2]);
  54     t_sample *out1 = (t_sample *)(w[3]);
  55     t_sample *out2 = (t_sample *)(w[4]);
  56     t_vcfctl *c = (t_vcfctl *)(w[5]);
  57     int n = (t_int)(w[6]);
  58     int i;
  59     t_sample re = c->c_re, re2;
  60     t_sample im = c->c_im;
  61     t_sample q = c->c_q;
  62     t_sample qinv = (q > 0 ? idiv(ftofix(1.0),q) : 0);
  63     t_sample ampcorrect = ftofix(2.0f) - idiv(ftofix(2.0f) , (q + ftofix(2.0f)));
  64     t_sample isr = c->c_isr;
  65     t_sample coefr, coefi;
  66     t_sample *tab = cos_table;
  67         t_sample oneminusr,cfindx,cf,r;
  68
  69     for (i = 0; i < n; i++)
  70     {
  71         cf = mult(*in2++,isr);
  72         if (cf < 0) cf = 0;
  73         cfindx = mult(cf,ftofix(0.15915494))>>(fix1-ILOGCOSTABSIZE); /* 1/2*PI */
  74         r = (qinv > 0 ? ftofix(1.01) - mult(cf,qinv) : 0);
  75
  76         if (r < 0) r = 0;
  77         oneminusr = ftofix(1.02f) - r; /* hand adapted */
  78
  79         /* r*cos(cf) */
  80         coefr = mult(r,tab[cfindx]);
  81
  82         /* r*sin(cf) */
  83         cfindx-=(ICOSTABSIZE>>2);
  84         cfindx += cfindx < 0 ? ICOSTABSIZE:0;
  85         coefi = mult(r,tab[cfindx]);
  86
  87         re2 = re;
  88         *out1++ = re = mult(ampcorrect,mult(oneminusr,*in1++))
  89             + mult(coefr,re2) - mult(coefi, im);
  90         *out2++ = im = mult(coefi,re2) + mult(coefr,im);
  91     }
  92     c->c_re = re;
  93     c->c_im = im;
  94     return (w+7);
  95 }
  96
  97 static void sigvcf_dsp(t_sigvcf *x, t_signal **sp)
  98 {
  99     /* TODO sr is hardcoded */
 100     x->x_ctl->c_isr = ftofix(0.0001424758);
 101 // idiv(ftofix(6.28318),ftofix(sp[0]->s_sr));
 102     post("%f",fixtof(x->x_ctl->c_isr));
 103    dsp_add(sigvcf_perform, 6,
 104         sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec, sp[3]->s_vec,
 105             x->x_ctl, sp[0]->s_n);
 106
 107 }
 108
 109 void vcf_tilde_setup(void)
 110 {
 111     sigvcf_class = class_new(gensym("vcf~"), (t_newmethod)sigvcf_new, 0,
 112         sizeof(t_sigvcf), 0, A_DEFFLOAT, 0);
 113     CLASS_MAINSIGNALIN(sigvcf_class, t_sigvcf, x_f);
 114     class_addmethod(sigvcf_class, (t_method)sigvcf_dsp, gensym("dsp"), 0);
 115     class_addmethod(sigvcf_class, (t_method)sigvcf_ft1,
 116         gensym("ft1"), A_FLOAT, 0);
 117     class_sethelpsymbol(sigvcf_class, gensym("lop~-help.pd"));
 118 }
 119