#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); }