shithub: soundpipe

ref: a7639e57d9ba60b4eab83a0658816b15f7c7699d
dir: /modules/rpt.c/

/* This code is placed in the public domain. */

#include <stdlib.h>
#include "soundpipe.h"

static int sp_rpt_set(sp_rpt *p, SPFLOAT bpm, int div, int rep);

int sp_rpt_create(sp_rpt **p)
{
    *p = malloc(sizeof(sp_rpt));
    return SP_OK;
}

int sp_rpt_destroy(sp_rpt **p)
{
    free((*p)->buf);
    free(*p);
    return SP_OK;
}

int sp_rpt_init(sp_data *sp, sp_rpt *p, SPFLOAT maxdur)
{
    uint32_t maxlen;
    maxlen = (uint32_t)maxdur * sp->sr;
    p->playpos = 0;
    p->bufpos = 0;
    p->running = 0;
    p->reps = 4;
    p->count = p->reps;
    p->maxlen = maxlen;
    p->buf = calloc(1, sizeof(SPFLOAT) * maxlen);
    p->size = maxlen;
    p->sr = sp->sr;
    p->bpm = 130;
    p->div = 4;
    p->rep = 4;
    p->rc = SP_OK;
    return SP_OK;
}

int sp_rpt_compute(sp_data *sp, sp_rpt *p, SPFLOAT *trig,
        SPFLOAT *in, SPFLOAT *out)
{
    SPFLOAT *buf = p->buf;

    if (p->rc == SP_NOT_OK) {
        *out = 0;
        return SP_NOT_OK;
    }

    if (*trig > 0) {
        p->rc = sp_rpt_set(p, p->bpm, p->div, p->rep);
        p->running = 1;
        p->playpos = 0;
        p->bufpos = 0;
        p->count = p->reps + 1;
    }

    if (p->bufpos < p->maxlen) {
        p->rc = sp_rpt_set(p, p->bpm, p->div, p->rep);
        buf[p->bufpos] = *in;
        p->bufpos++;
    } else {
        p->running = 0;
    }

    if(p->running && p->count > 0) {
        if (p->playpos == 0) {
            p->count--;
        }
        *out = buf[p->playpos];
        p->playpos = (p->playpos + 1) % p->size;
    } else {
        *out = *in;
    }

    return SP_OK;
}

static int sp_rpt_set(sp_rpt *p, SPFLOAT bpm, int div, int rep)
{
    uint32_t size = (p->sr * (60.0 / bpm)) / (SPFLOAT) div;
    p->reps = rep;
    if (size > p->maxlen) {
        fprintf(stderr, "Error: not enough memory allocated for buffer.\n");
        return SP_NOT_OK;
    } else if(size <= 0) {
        fprintf(stderr, "Error: Size cannot be zero.\n");
        return SP_NOT_OK;
    } else {
        p->size = size;
    }
    return SP_OK;
}