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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 "sine.h"
void sine_free();
typedef struct sine_susp_struct {
snd_susp_node susp;
long terminate_cnt;
long phase;
long ph_incr;
} sine_susp_node, *sine_susp_type;
sample_type sine_table[SINE_TABLE_LEN + 1];
void sine_init()
{
int i;
for (i = 0; i <= SINE_TABLE_LEN; i++)
sine_table[i] = (sample_type) (sin((PI * 2 * i) / SINE_TABLE_LEN));
}
void sine__fetch(register sine_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 long phase_reg;
register long ph_incr_reg;
falloc_sample_block(out, "sine__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 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;
phase_reg = susp->phase;
ph_incr_reg = susp->ph_incr;
out_ptr_reg = out_ptr;
if (n) do { /* the inner sample computation loop */
*out_ptr_reg++ = sine_table[phase_reg >> SINE_TABLE_SHIFT];
phase_reg += ph_incr_reg;
phase_reg &= SINE_TABLE_MASK;;
} while (--n); /* inner loop */
susp->phase = (susp->phase + susp->ph_incr * togo) & SINE_TABLE_MASK;
out_ptr += 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;
}
} /* sine__fetch */
void sine_free(sine_susp_type susp)
{
ffree_generic(susp, sizeof(sine_susp_node), "sine_free");
}
void sine_print_tree(sine_susp_type susp, int n)
{
}
sound_type snd_make_sine(time_type t0, double hz, rate_type sr, time_type d)
{
register sine_susp_type susp;
/* sr specified as input parameter */
/* t0 specified as input parameter */
sample_type scale_factor = 1.0F;
falloc_generic(susp, sine_susp_node, "snd_make_sine");
susp->phase = 0;
susp->ph_incr = round(((hz * SINE_TABLE_LEN) * (1 << SINE_TABLE_SHIFT) / sr));
susp->susp.fetch = sine__fetch;
susp->terminate_cnt = round((d) * sr);
/* initialize susp state */
susp->susp.free = sine_free;
susp->susp.sr = sr;
susp->susp.t0 = t0;
susp->susp.mark = NULL;
susp->susp.print_tree = sine_print_tree;
susp->susp.name = "sine";
susp->susp.log_stop_cnt = UNKNOWN;
susp->susp.current = 0;
return sound_create((snd_susp_type)susp, t0, sr, scale_factor);
}
sound_type snd_sine(time_type t0, double hz, rate_type sr, time_type d)
{
return snd_make_sine(t0, hz, sr, d);
}
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