resoncv.c

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	susp->bw_pHaSe = bw_pHaSe_ReG;
	susp->bw_x1_sample = bw_x1_sample_reg;
	/* using s1_ptr_reg is a bad idea on RS/6000: */
	susp->s1_ptr += togo;
	out_ptr += togo;
	susp_took(s1_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;
    }
    /* test for logical stop */
    if (susp->logically_stopped) {
	snd_list->logically_stopped = true;
    } else if (susp->susp.log_stop_cnt == susp->susp.current) {
	susp->logically_stopped = true;
    }
} /* resoncv_ni_fetch */


void resoncv_nr_fetch(register resoncv_susp_type susp, snd_list_type snd_list)
{
    int cnt = 0; /* how many samples computed */
    sample_type bw_val;
    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 scale1_reg;
    register double c3co_reg;
    register double coshz_reg;
    register double c2_reg;
    register double c1_reg;
    register int normalization_reg;
    register double y1_reg;
    register double y2_reg;
    register sample_block_values_type s1_ptr_reg;
    falloc_sample_block(out, "resoncv_nr_fetch");
    out_ptr = out->samples;
    snd_list->block = out;

    /* make sure sounds are primed with first values */
    if (!susp->started) {
	susp->started = true;
	susp->bw_pHaSe = 1.0;
    }

    susp_check_term_samples(bw, bw_ptr, bw_cnt);

    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 s1 input sample block: */
	susp_check_term_log_samples(s1, s1_ptr, s1_cnt);
	togo = MIN(togo, susp->s1_cnt);

	/* grab next bw_x1_sample when phase goes past 1.0; */
	/* use bw_n (computed below) to avoid roundoff errors: */
	if (susp->bw_n <= 0) {
	    double c3p1;
	    double c3t4;
	    double omc3;
	    susp_check_term_samples(bw, bw_ptr, bw_cnt);
	    susp->bw_x1_sample = susp_fetch_sample(bw, bw_ptr, bw_cnt);
	    susp->bw_pHaSe -= 1.0;
	    /* bw_n gets number of samples before phase exceeds 1.0: */
	    susp->bw_n = (long) ((1.0 - susp->bw_pHaSe) *
					susp->output_per_bw);
	    susp->c3co = exp(susp->bw_x1_sample);
	    c3p1 = susp->c3co + 1.0;
	    c3t4 = susp->c3co * 4.0;
	    omc3 = 1.0 - susp->c3co;
	    susp->c2 = c3t4 * susp->coshz / c3p1;
	    susp->c1 = (susp->normalization == 0 ? 1.0 :
          (susp->normalization == 1 ? omc3 * sqrt(1.0 - susp->c2 * susp->c2 / c3t4) :
              sqrt(c3p1 * c3p1 - susp->c2 * susp->c2) * omc3 / c3p1)) * susp->scale1;
	}
	togo = MIN(togo, susp->bw_n);
	bw_val = susp->bw_x1_sample;
	/* 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;
	}


	/* don't run past logical stop time */
	if (!susp->logically_stopped && susp->susp.log_stop_cnt != UNKNOWN) {
	    int to_stop = susp->susp.log_stop_cnt - (susp->susp.current + cnt);
	    /* break if to_stop == 0 (we're at the logical stop)
	     * AND cnt > 0 (we're not at the beginning of the
	     * output block).
	     */
	    if (to_stop < togo) {
		if (to_stop == 0) {
		    if (cnt) {
			togo = 0;
			break;
		    } else /* keep togo as is: since cnt == 0, we
		            * can set the logical stop flag on this
		            * output block
		            */
			susp->logically_stopped = true;
		} else /* limit togo so we can start a new
		        * block at the LST
		        */
		    togo = to_stop;
	    }
	}

	n = togo;
	scale1_reg = susp->scale1;
	c3co_reg = susp->c3co;
	coshz_reg = susp->coshz;
	c2_reg = susp->c2;
	c1_reg = susp->c1;
	normalization_reg = susp->normalization;
	y1_reg = susp->y1;
	y2_reg = susp->y2;
	s1_ptr_reg = susp->s1_ptr;
	out_ptr_reg = out_ptr;
	if (n) do { /* the inner sample computation loop */
{ double y0 = c1_reg * *s1_ptr_reg++ + c2_reg * y1_reg - c3co_reg * y2_reg;
            *out_ptr_reg++ = (sample_type) y0; 
            y2_reg = y1_reg; y1_reg = y0; };
	} while (--n); /* inner loop */

	susp->y1 = y1_reg;
	susp->y2 = y2_reg;
	/* using s1_ptr_reg is a bad idea on RS/6000: */
	susp->s1_ptr += togo;
	out_ptr += togo;
	susp_took(s1_cnt, togo);
	susp->bw_pHaSe += togo * susp->bw_pHaSe_iNcR;
	susp->bw_n -= 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;
    }
    /* test for logical stop */
    if (susp->logically_stopped) {
	snd_list->logically_stopped = true;
    } else if (susp->susp.log_stop_cnt == susp->susp.current) {
	susp->logically_stopped = true;
    }
} /* resoncv_nr_fetch */


void resoncv_toss_fetch(susp, snd_list)
  register resoncv_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 s1 up to final_time for this block of zeros */
    while ((round((final_time - susp->s1->t0) * susp->s1->sr)) >=
	   susp->s1->current)
	susp_get_samples(s1, s1_ptr, s1_cnt);
    /* fetch samples from bw up to final_time for this block of zeros */
    while ((round((final_time - susp->bw->t0) * susp->bw->sr)) >=
	   susp->bw->current)
	susp_get_samples(bw, bw_ptr, bw_cnt);
    /* convert to normal processing when we hit final_count */
    /* we want each signal positioned at final_time */
    n = round((final_time - susp->s1->t0) * susp->s1->sr -
         (susp->s1->current - susp->s1_cnt));
    susp->s1_ptr += n;
    susp_took(s1_cnt, n);
    n = round((final_time - susp->bw->t0) * susp->bw->sr -
         (susp->bw->current - susp->bw_cnt));
    susp->bw_ptr += n;
    susp_took(bw_cnt, n);
    susp->susp.fetch = susp->susp.keep_fetch;
    (*(susp->susp.fetch))(susp, snd_list);
}


void resoncv_mark(resoncv_susp_type susp)
{
    sound_xlmark(susp->s1);
    sound_xlmark(susp->bw);
}


void resoncv_free(resoncv_susp_type susp)
{
    sound_unref(susp->s1);
    sound_unref(susp->bw);
    ffree_generic(susp, sizeof(resoncv_susp_node), "resoncv_free");
}


void resoncv_print_tree(resoncv_susp_type susp, int n)
{
    indent(n);
    stdputstr("s1:");
    sound_print_tree_1(susp->s1, n);

    indent(n);
    stdputstr("bw:");
    sound_print_tree_1(susp->bw, n);
}


sound_type snd_make_resoncv(sound_type s1, double hz, sound_type bw, int normalization)
{
    register resoncv_susp_type susp;
    rate_type sr = s1->sr;
    time_type t0 = MAX(s1->t0, bw->t0);
    int interp_desc = 0;
    sample_type scale_factor = 1.0F;
    time_type t0_min = t0;
    falloc_generic(susp, resoncv_susp_node, "snd_make_resoncv");
    susp->scale1 = s1->scale;
    susp->c3co = 0.0;
    susp->coshz = cos(hz * PI2 / s1->sr);
    susp->c2 = 0.0;
    susp->c1 = 0.0;
    susp->normalization = normalization;
    susp->y1 = 0.0;
    susp->y2 = 0.0;
    bw->scale = (sample_type) (bw->scale * (-PI2 / s1->sr));

    /* select a susp fn based on sample rates */
    interp_desc = (interp_desc << 2) + interp_style(s1, sr);
    interp_desc = (interp_desc << 2) + interp_style(bw, sr);
    switch (interp_desc) {
      case INTERP_sn: /* handled below */
      case INTERP_ss: /* handled below */
      case INTERP_nn: /* handled below */
      case INTERP_ns: susp->susp.fetch = resoncv_ns_fetch; break;
      case INTERP_si: /* handled below */
      case INTERP_ni: susp->susp.fetch = resoncv_ni_fetch; break;
      case INTERP_sr: /* handled below */
      case INTERP_nr: susp->susp.fetch = resoncv_nr_fetch; break;
      default: snd_badsr(); break;
    }

    susp->terminate_cnt = UNKNOWN;
    /* handle unequal start times, if any */
    if (t0 < s1->t0) sound_prepend_zeros(s1, t0);
    if (t0 < bw->t0) sound_prepend_zeros(bw, t0);
    /* minimum start time over all inputs: */
    t0_min = MIN(s1->t0, MIN(bw->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 = resoncv_toss_fetch;
    }

    /* initialize susp state */
    susp->susp.free = resoncv_free;
    susp->susp.sr = sr;
    susp->susp.t0 = t0;
    susp->susp.mark = resoncv_mark;
    susp->susp.print_tree = resoncv_print_tree;
    susp->susp.name = "resoncv";
    susp->logically_stopped = false;
    susp->susp.log_stop_cnt = logical_stop_cnt_cvt(s1);
    susp->started = false;
    susp->susp.current = 0;
    susp->s1 = s1;
    susp->s1_cnt = 0;
    susp->bw = bw;
    susp->bw_cnt = 0;
    susp->bw_pHaSe = 0.0;
    susp->bw_pHaSe_iNcR = bw->sr / sr;
    susp->bw_n = 0;
    susp->output_per_bw = sr / bw->sr;
    return sound_create((snd_susp_type)susp, t0, sr, scale_factor);
}


sound_type snd_resoncv(sound_type s1, double hz, sound_type bw, int normalization)
{
    sound_type s1_copy = sound_copy(s1);
    sound_type bw_copy = sound_copy(bw);
    return snd_make_resoncv(s1_copy, hz, bw_copy, normalization);
}