/* This code is placed in the public domain. */ #include <stdlib.h>#include <math.h>#include "soundpipe.h" int sp_tseg_create(sp_tseg **p){    *p = malloc(sizeof(sp_tseg));    return SP_OK;} int sp_tseg_destroy(sp_tseg **p){    free(*p);    return SP_OK;} int sp_tseg_init(sp_data *sp, sp_tseg *p, SPFLOAT ibeg){    p->beg = ibeg;    p->end = 1.0;    p->val = ibeg;    p->type = -3;    p->slope = 1.0;    p->dur = 1.0;    p->tdivnsteps = 0.0;    p->count = 0;    p->steps = p->dur * sp->sr;    return SP_OK;} int sp_tseg_compute(sp_data *sp, sp_tseg *p, SPFLOAT *in, SPFLOAT *out){    *out = p->val;    if(*in != 0) {        p->slope = 1.0 / (1.0 - exp(p->type));        p->beg = p->val;        p->count = 0;        p->steps = p->dur * sp->sr;        p->tdivnsteps = (SPFLOAT)p->type / (p->steps - 1);    }    if(p->count < p->steps) {        *out = p->beg + (p->end - p->beg) *            ((1 - exp(p->count * p->tdivnsteps)) * p->slope);        p->val = *out;        p->count++;    }    return SP_OK;}