ref: 70285956de156f146984f42c8ffa42401d42edd7
dir: /modules/phasor.c/
/* * Phasor * * A phasor produces a non-bandlimited sawtooth wave, * normalized to be in range 0-1. Phasors are most * frequently used to create table-lookup oscillators. */ #include <stdlib.h> #include "soundpipe.h" int sp_phasor_create(sp_phasor **p) { *p = malloc(sizeof(sp_phasor)); return SP_OK; } int sp_phasor_destroy(sp_phasor **p) { free(*p); return SP_OK; } int sp_phasor_init(sp_data *sp, sp_phasor *p, SPFLOAT iphs) { p->freq = 440; p->phs = iphs; p->onedsr = 1.0 / sp->sr; return SP_OK; } int sp_phasor_compute(sp_data *sp, sp_phasor *p, SPFLOAT *in, SPFLOAT *out) { SPFLOAT phs; SPFLOAT incr; phs = p->phs; incr = p->freq * p->onedsr; *out = phs; phs += incr; if (phs >= 1.0) { phs -= 1.0; } else if (phs < 0.0) { phs += 1.0; } p->phs = phs; return SP_OK; }