1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
|
/*
* copyright Steve Harris, Ben Saylor
* see GPL.txt
*/
#include <math.h>
#include <string.h>
#include "m_pd.h"
#ifdef NT
#define inline __inline
#define M_PI 3.14159265358979323846
#pragma warning( disable : 4244 )
#pragma warning( disable : 4305 )
#endif
// Number of filter oversamples
#define F_R 3
// Denormalise floats, only actually needed for PIII and very recent PowerPC
#define FLUSH_TO_ZERO(fv) (((*(unsigned int*)&(fv))&0x7f800000)==0)?0.0f:(fv)
/* pd's samplerate */
float fs;
static t_class *svf_class;
typedef struct _svf
{
t_object x_obj;
float f; // 2.0*sin(PI*fs/(fc*r));
float q; // 2.0*cos(pow(q, 0.1)*PI*0.5);
float qnrm; // sqrt(m/2.0f+0.01f);
float h; // high pass output
float b; // band pass output
float l; // low pass output
float p; // peaking output (allpass with resonance)
float n; // notch output
float *op; // pointer to output value
} t_svf;
/* Store data in SVF struct, takes the sampling frequency, cutoff frequency
and Q, and fills in the structure passed */
//static inline void setup_svf(sv_filter *sv, float fs, float fc, float q, int t) {
static inline void setup_svf(t_svf *sv, float fc, float q) {
sv->f = 2.0f * sin(M_PI * fc / (float)(fs * F_R));
sv->q = 2.0f * cos(pow(q, 0.1f) * M_PI * 0.5f);
sv->qnrm = sqrt(sv->q/2.0+0.01);
}
/* Run one sample through the SV filter. Filter is by andy@vellocet */
static inline float run_svf(t_svf *sv, float in) {
float out;
int i;
in = sv->qnrm * in ;
for (i=0; i < F_R; i++) {
// only needed for pentium chips
// OLD VERSION
in = FLUSH_TO_ZERO(in);
sv->l = FLUSH_TO_ZERO(sv->l);
// new versions, thanks to Damon Chaplin, inserted by Ed Kelly, not yet working!!!
//in = ((int)in & 0x7f800000)==0?0.0f:in;
//sv->l = ((int)sv->l & 0x7f800000)==0?0.0f:sv->l;
// very slight waveshape for extra stability
sv->b = sv->b - sv->b * sv->b * sv->b * 0.001f;
// regular state variable code here
// the notch and peaking outputs are optional
sv->h = in - sv->l - sv->q * sv->b;
sv->b = sv->b + sv->f * sv->h;
sv->l = sv->l + sv->f * sv->b;
sv->n = sv->l + sv->h;
sv->p = sv->l - sv->h;
out = *(sv->op);
in = out;
}
return out;
}
static void svf_setstate_LP(t_svf *sv)
{
sv->op = &(sv->l);
}
static void svf_setstate_HP(t_svf *sv)
{
sv->op = &(sv->h);
}
static void svf_setstate_BP(t_svf *sv)
{
sv->op = &(sv->b);
}
static void svf_setstate_BR(t_svf *sv)
{
sv->op = &(sv->n);
}
static void svf_setstate_AP(t_svf *sv)
{
sv->op = &(sv->p);
}
static t_int *svf_perform(t_int *w)
{
t_svf *obj = (t_svf *)(w[1]);
t_float *in = (t_float *)(w[2]);
t_float *freq = (t_float *)(w[3]);
t_float *q = (t_float *)(w[4]);
t_float *res = (t_float *)(w[5]);
t_float *out = (t_float *)(w[6]);
int n = (int)(w[7]);
while (n--) {
float f = *(in++);
setup_svf(obj, *(freq++), *(q++));
*(out++) = run_svf(obj, f + ((obj->b) * (*(res++))));
}
return (w+8);
}
static void svf_dsp(t_svf *x, t_signal **sp)
{
dsp_add(svf_perform, 7, x, sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec, sp[3]->s_vec, sp[4]->s_vec, sp[0]->s_n);
}
static void *svf_new(t_symbol *s, int argc, t_atom *argv)
{
char string[11];
t_svf *x = (t_svf *)pd_new(svf_class);
svf_setstate_LP(x);
if (argc > 0) {
atom_string(argv, string, 10);
if (!strcmp(string, "high"))
svf_setstate_HP(x);
if (!strcmp(string, "band"))
svf_setstate_BP(x);
if (!strcmp(string, "notch"))
svf_setstate_BR(x);
if (!strcmp(string, "peak"))
svf_setstate_AP(x);
}
inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
outlet_new(&x->x_obj, gensym("signal"));
return (x);
}
void svf_tilde_setup(void)
{
fs = sys_getsr();
svf_class = class_new(gensym("svf~"), (t_newmethod)svf_new, 0, sizeof(t_svf), 0, A_GIMME, 0);
class_addmethod(svf_class, nullfn, gensym("signal"), 0);
class_addmethod(svf_class, (t_method)svf_dsp, gensym("dsp"), 0);
class_addmethod(svf_class, (t_method)svf_setstate_LP, gensym("low"), 0);
class_addmethod(svf_class, (t_method)svf_setstate_HP, gensym("high"), 0);
class_addmethod(svf_class, (t_method)svf_setstate_BP, gensym("band"), 0);
class_addmethod(svf_class, (t_method)svf_setstate_BR, gensym("notch"), 0);
class_addmethod(svf_class, (t_method)svf_setstate_AP, gensym("peak"), 0);
}
|