ref: 29851f9c445d41cd82e422cb4b8c13fd2a13aea5
dir: /modules/tenvx.c/
/* This code is placed in the public domain. */ #include <stdlib.h> #include <math.h> #include "soundpipe.h" int sp_tenvx_create(sp_tenvx **p) { *p = malloc(sizeof(sp_tenvx)); return SP_OK; } int sp_tenvx_destroy(sp_tenvx **p) { free(*p); return SP_OK; } int sp_tenvx_init(sp_data *sp, sp_tenvx *p) { p->hold = 0.5; p->atk = 0.5; p->rel = 0.5; p->a_a = p->b_a = 0; p->a_r = p->b_r = 0; p->y = 0; p->count = (uint32_t) (p->hold * sp->sr); return SP_OK; } int sp_tenvx_compute(sp_data *sp, sp_tenvx *p, SPFLOAT *in, SPFLOAT *out) { *out = 0; if(*in != 0) { p->a_a = exp(-1.0/(p->atk * sp->sr)); p->b_a = 1.0 - p->a_a; p->a_r = exp(-1.0/(p->rel * sp->sr)); p->b_r = 1.0 - p->a_r; p->count = (uint32_t) (p->hold * sp->sr); } if(p->count > 0) { *out = p->b_a + p->a_a * p->y; p->y = *out; p->count--; } else { *out = p->a_r * p->y; p->y = *out; } return SP_OK; }