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#include "stdio.h"
#ifndef mips
#include "stdlib.h"
#endif
#include "xlisp.h"
#include "sound.h"
#include "falloc.h"
#include "cext.h"
#include "delay.h"
void delay_free();
typedef struct delay_susp_struct {
snd_susp_node susp;
long terminate_cnt;
sound_type input;
long input_cnt;
sample_block_values_type input_ptr;
double feedback;
long delaylen;
sample_type *delaybuf;
sample_type *delayptr;
sample_type *endptr;
} delay_susp_node, *delay_susp_type;
void delay_n_fetch(register delay_susp_type susp, snd_list_type snd_list)
{
int cnt = 0; /* how many samples computed */
int togo;
int n;
sample_block_type out;
register sample_block_values_type out_ptr;
register sample_block_values_type out_ptr_reg;
register double feedback_reg;
register sample_type * delayptr_reg;
register sample_type * endptr_reg;
register sample_block_values_type input_ptr_reg;
falloc_sample_block(out, "delay_n_fetch");
out_ptr = out->samples;
snd_list->block = out;
while (cnt < max_sample_block_len) { /* outer loop */
/* first compute how many samples to generate in inner loop: */
/* don't overflow the output sample block: */
togo = max_sample_block_len - cnt;
/* don't run past the input input sample block: */
susp_check_term_samples(input, input_ptr, input_cnt);
togo = MIN(togo, susp->input_cnt);
/* don't run past terminate time */
if (susp->terminate_cnt != UNKNOWN &&
susp->terminate_cnt <= susp->susp.current + cnt + togo) {
togo = susp->terminate_cnt - (susp->susp.current + cnt);
if (togo == 0) break;
}
n = togo;
feedback_reg = susp->feedback;
delayptr_reg = susp->delayptr;
endptr_reg = susp->endptr;
input_ptr_reg = susp->input_ptr;
out_ptr_reg = out_ptr;
if (n) do { /* the inner sample computation loop */
*out_ptr_reg++ = *delayptr_reg;
*delayptr_reg = (sample_type) (*delayptr_reg * feedback_reg) + *input_ptr_reg++;
if (++delayptr_reg >= endptr_reg) delayptr_reg = susp->delaybuf;;
} while (--n); /* inner loop */
susp->delayptr = delayptr_reg;
/* using input_ptr_reg is a bad idea on RS/6000: */
susp->input_ptr += togo;
out_ptr += togo;
susp_took(input_cnt, togo);
cnt += togo;
} /* outer loop */
/* test for termination */
if (togo == 0 && cnt == 0) {
snd_list_terminate(snd_list);
} else {
snd_list->block_len = cnt;
susp->susp.current += cnt;
}
} /* delay_n_fetch */
void delay_toss_fetch(susp, snd_list)
register delay_susp_type susp;
snd_list_type snd_list;
{
long final_count = susp->susp.toss_cnt;
time_type final_time = susp->susp.t0;
long n;
/* fetch samples from input up to final_time for this block of zeros */
while ((round((final_time - susp->input->t0) * susp->input->sr)) >=
susp->input->current)
susp_get_samples(input, input_ptr, input_cnt);
/* convert to normal processing when we hit final_count */
/* we want each signal positioned at final_time */
n = round((final_time - susp->input->t0) * susp->input->sr -
(susp->input->current - susp->input_cnt));
susp->input_ptr += n;
susp_took(input_cnt, n);
susp->susp.fetch = susp->susp.keep_fetch;
(*(susp->susp.fetch))(susp, snd_list);
}
void delay_mark(delay_susp_type susp)
{
sound_xlmark(susp->input);
}
void delay_free(delay_susp_type susp)
{
free(susp->delaybuf); sound_unref(susp->input);
ffree_generic(susp, sizeof(delay_susp_node), "delay_free");
}
void delay_print_tree(delay_susp_type susp, int n)
{
indent(n);
stdputstr("input:");
sound_print_tree_1(susp->input, n);
}
sound_type snd_make_delay(sound_type input, time_type delay, double feedback)
{
register delay_susp_type susp;
rate_type sr = input->sr;
time_type t0 = input->t0;
int interp_desc = 0;
sample_type scale_factor = 1.0F;
time_type t0_min = t0;
/* combine scale factors of linear inputs (INPUT) */
scale_factor *= input->scale;
input->scale = 1.0F;
/* try to push scale_factor back to a low sr input */
if (input->sr < sr) { input->scale = scale_factor; scale_factor = 1.0F; }
falloc_generic(susp, delay_susp_node, "snd_make_delay");
susp->feedback = feedback;
susp->delaylen = MAX(1, round(input->sr * delay));
susp->delaybuf = (sample_type *) calloc (susp->delaylen, sizeof(sample_type));
susp->delayptr = susp->delaybuf;
susp->endptr = susp->delaybuf + susp->delaylen;
susp->susp.fetch = delay_n_fetch;
susp->terminate_cnt = UNKNOWN;
/* handle unequal start times, if any */
if (t0 < input->t0) sound_prepend_zeros(input, t0);
/* minimum start time over all inputs: */
t0_min = MIN(input->t0, t0);
/* how many samples to toss before t0: */
susp->susp.toss_cnt = (long) ((t0 - t0_min) * sr + 0.5);
if (susp->susp.toss_cnt > 0) {
susp->susp.keep_fetch = susp->susp.fetch;
susp->susp.fetch = delay_toss_fetch;
}
/* initialize susp state */
susp->susp.free = delay_free;
susp->susp.sr = sr;
susp->susp.t0 = t0;
susp->susp.mark = delay_mark;
susp->susp.print_tree = delay_print_tree;
susp->susp.name = "delay";
susp->susp.log_stop_cnt = UNKNOWN;
susp->susp.current = 0;
susp->input = input;
susp->input_cnt = 0;
return sound_create((snd_susp_type)susp, t0, sr, scale_factor);
}
sound_type snd_delay(sound_type input, time_type delay, double feedback)
{
sound_type input_copy = sound_copy(input);
return snd_make_delay(input_copy, delay, feedback);
}
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