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#include "opnassg.h"
#ifdef LIBOPNA_ENABLE_OSCILLO
#include "oscillo/oscillo.h"
#endif
// if (i < 2) voltable[i] = 0;
// else voltable[i] = round((0x7fff / 3.0) * pow(2.0, (i - 31)/4.0));
/*
static const int16_t voltable[32] = {
0, 0, 72, 85,
101, 121, 144, 171,
203, 241, 287, 341,
406, 483, 574, 683,
812, 965, 1148, 1365,
1624, 1931, 2296, 2731,
3247, 3862, 4592, 5461,
6494, 7723, 9185, 10922
};
*/
// captured from YMF288
static const uint16_t voltable[32] = {
0, 0, 0, 0,
4, 8, 12, 16,
20, 24, 28, 32,
36, 44, 52, 64,
76, 92, 108, 128,
152, 180, 216, 256,
304, 360, 428, 512,
608, 720, 856, 1020,
};
/*
* on YMF288:
* when TP >= 8:
*
* |
* +voltab + ----- ----- --
* |
* 0 +---------------------------
* |
* -voltab + ----- -----
* |
*
* when TP < 8:
* |
* +voltab + ----------------------
* |
* 0 +---------------------------
* |
* -voltab +
* |
*
* when /TONE=1 && /NOISE=1 (both diabled)
* |
* +2voltab + ----------------------
* |
* +
* |
* 0 +---------------------------
* |
*/
// GNU Octave
// Fc = 7987200
// Ff = Fc/144
// Fs = Fc/32
// Fe = 20000
// O = (((Ff/2)-Fe)*2)/(Fs/2)
// B = 128 * O / 2
// FILTER=sinc(linspace(-127.5,127.5,256)*2/9/2).*rotdim(kaiser(256,B))
// FILTERI=round(FILTER(1:128).*32768)
#if 0
const int16_t opna_ssg_sinctable[OPNA_SSG_SINCTABLELEN*2] = {
1, 0, -1, -2, -3, -5, -6, -6,
-6, -5, -2, 2, 7, 11, 16, 19,
20, 18, 13, 5, -5, -17, -29, -38,
-44, -45, -40, -29, -11, 12, 36, 60,
79, 90, 91, 80, 56, 21, -22, -68,
-112, -146, -166, -166, -144, -100, -37, 39,
119, 193, 251, 282, 280, 241, 166, 61,
-64, -195, -315, -406, -455, -450, -385, -264,
-96, 101, 306, 491, 632, 705, 694, 593,
405, 147, -154, -464, -744, -954, -1062, -1043,
-889, -607, -220, 230, 692, 1108, 1421, 1580,
1552, 1322, 902, 328, -343, -1032, -1655, -2125,
-2369, -2333, -1994, -1365, -498, 523, 1585, 2557,
3306, 3714, 3690, 3185, 2206, 815, -868, -2673,
-4391, -5798, -6670, -6809, -6067, -4359, -1681, 1886,
6178, 10957, 15928, 20765, 25133, 28724, 31275, 32600,
32600, 31275, 28724, 25133, 20765, 15928, 10957, 6178,
1886, -1681, -4359, -6067, -6809, -6670, -5798, -4391,
-2673, -868, 815, 2206, 3185, 3690, 3714, 3306,
2557, 1585, 523, -498, -1365, -1994, -2333, -2369,
-2125, -1655, -1032, -343, 328, 902, 1322, 1552,
1580, 1421, 1108, 692, 230, -220, -607, -889,
-1043, -1062, -954, -744, -464, -154, 147, 405,
593, 694, 705, 632, 491, 306, 101, -96,
-264, -385, -450, -455, -406, -315, -195, -64,
61, 166, 241, 280, 282, 251, 193, 119,
39, -37, -100, -144, -166, -166, -146, -112,
-68, -22, 21, 56, 80, 91, 90, 79,
60, 36, 12, -11, -29, -40, -45, -44,
-38, -29, -17, -5, 5, 13, 18, 20,
19, 16, 11, 7, 2, -2, -5, -6,
-6, -6, -5, -3, -2, -1, 0, 1,
};
#endif
const int16_t opna_ssg_sinctable[OPNA_SSG_SINCTABLELEN*2] = {
1, -1, -3, -6, -6, -2, 7, 16,
20, 13, -5, -29, -44, -40, -11, 36,
79, 91, 56, -22, -112, -166, -144, -37,
119, 251, 280, 166, -64, -315, -455, -385,
-96, 306, 632, 694, 405, -154, -744, -1062,
-889, -220, 692, 1421, 1552, 902, -343, -1655,
-2369, -1994, -498, 1585, 3306, 3690, 2206, -868,
-4391, -6670, -6067, -1681, 6178, 15928, 25133, 31275,
32600, 28724, 20765, 10957, 1886, -4359, -6809, -5798,
-2673, 815, 3185, 3714, 2557, 523, -1365, -2333,
-2125, -1032, 328, 1322, 1580, 1108, 230, -607,
-1043, -954, -464, 147, 593, 705, 491, 101,
-264, -450, -406, -195, 61, 241, 282, 193,
39, -100, -166, -146, -68, 21, 80, 90,
60, 12, -29, -45, -38, -17, 5, 18,
19, 11, 2, -5, -6, -5, -2, 0,
0, -2, -5, -6, -5, 2, 11, 19,
18, 5, -17, -38, -45, -29, 12, 60,
90, 80, 21, -68, -146, -166, -100, 39,
193, 282, 241, 61, -195, -406, -450, -264,
101, 491, 705, 593, 147, -464, -954, -1043,
-607, 230, 1108, 1580, 1322, 328, -1032, -2125,
-2333, -1365, 523, 2557, 3714, 3185, 815, -2673,
-5798, -6809, -4359, 1886, 10957, 20765, 28724, 32600,
31275, 25133, 15928, 6178, -1681, -6067, -6670, -4391,
-868, 2206, 3690, 3306, 1585, -498, -1994, -2369,
-1655, -343, 902, 1552, 1421, 692, -220, -889,
-1062, -744, -154, 405, 694, 632, 306, -96,
-385, -455, -315, -64, 166, 280, 251, 119,
-37, -144, -166, -112, -22, 56, 91, 79,
36, -11, -40, -44, -29, -5, 13, 20,
16, 7, -2, -6, -6, -3, -1, 1,
};
opna_ssg_sinc_calc_func_type opna_ssg_sinc_calc_func = opna_ssg_sinc_calc_c;
void opna_ssg_reset(struct opna_ssg *ssg) {
*ssg = (struct opna_ssg) {
.mix = 0x10000,
.ymf288 = true,
};
}
void opna_ssg_resampler_reset(struct opna_ssg_resampler *resampler) {
for (int i = 0; i < OPNA_SSG_SINCTABLELEN; i++) {
resampler->buf[i] = 0;
}
resampler->index = 0;
#ifdef LIBOPNA_ENABLE_LEVELDATA
for (int c = 0; c < 3; c++) {
leveldata_init(&resampler->leveldata[c]);
}
#endif
}
void opna_ssg_writereg(struct opna_ssg *ssg, unsigned reg, unsigned val) {
if (reg > 0xfu) return;
val &= 0xff;
ssg->regs[reg] = val;
if (reg == 0xd) {
ssg->env_att = ssg->regs[0xd] & 0x4;
if (ssg->regs[0xd] & 0x8) {
ssg->env_alt = ssg->regs[0xd] & 0x2;
ssg->env_hld = ssg->regs[0xd] & 0x1;
} else {
ssg->env_alt = ssg->env_att;
ssg->env_hld = true;
}
ssg->env_holding = false;
ssg->env_level = 0;
ssg->env_counter = 0;
}
}
unsigned opna_ssg_readreg(const struct opna_ssg *ssg, unsigned reg) {
if (reg > 0xfu) return 0xff;
return ssg->regs[reg];
}
unsigned opna_ssg_tone_period(const struct opna_ssg *ssg, int ch) {
if (ch < 0) return 0;
if (ch >= 3) return 0;
return ssg->regs[0+ch*2] | ((ssg->regs[1+ch*2] & 0xf) << 8);
}
static bool opna_ssg_chan_env(const struct opna_ssg *ssg, int chan) {
return ssg->regs[0x8+chan] & 0x10;
}
static int opna_ssg_tone_volume(const struct opna_ssg *ssg, int chan) {
return ssg->regs[0x8+chan] & 0xf;
}
static bool opna_ssg_tone_out(const struct opna_ssg *ssg, int chan) {
unsigned reg = ssg->regs[0x7] >> chan;
return (ssg->ch[chan].out || (reg & 0x1)) && ((ssg->lfsr & 1) || (reg & 0x8));
}
static bool opna_ssg_tone_out_ymf288(const struct opna_ssg *ssg, int chan) {
unsigned reg = ssg->regs[0x7] >> chan;
bool toneout =
opna_ssg_tone_period(ssg, chan) < 8 ? true : ssg->ch[chan].out;
return (toneout || (reg & 0x1)) && ((ssg->lfsr & 1) || (reg & 0x8));
}
static bool opna_ssg_tone_silent(const struct opna_ssg *ssg, int chan) {
unsigned reg = ssg->regs[0x7] >> chan;
return (reg & 0x1) && (reg & 0x8);
}
static int opna_ssg_noise_period(const struct opna_ssg *ssg) {
return ssg->regs[0x6] & 0x1f;
}
static int opna_ssg_env_period(const struct opna_ssg *ssg) {
return (ssg->regs[0xc] << 8) | ssg->regs[0xb];
}
static int opna_ssg_env_level(const struct opna_ssg *ssg) {
return ssg->env_att ? ssg->env_level : 31-ssg->env_level;
}
int opna_ssg_channel_level(const struct opna_ssg *ssg, int ch) {
return opna_ssg_chan_env(ssg, ch)
? opna_ssg_env_level(ssg)
: (opna_ssg_tone_volume(ssg, ch) << 1) + 1;
}
#define COEFF 0x3fff
#define COEFFSH 14
// 3 samples per frame
// output buf: 0 1 2 x 0 1 2 x ...
void opna_ssg_generate_raw(struct opna_ssg *ssg, int16_t *buf, int samples) {
for (int i = 0; i < samples; i++) {
if (((++ssg->noise_counter) >> 1) >= opna_ssg_noise_period(ssg)) {
ssg->noise_counter = 0;
ssg->lfsr |= (!((ssg->lfsr & 1) ^ ((ssg->lfsr >> 3) & 1))) << 17;
ssg->lfsr >>= 1;
}
if (!ssg->env_holding) {
if (++ssg->env_counter >= opna_ssg_env_period(ssg)) {
ssg->env_counter = 0;
ssg->env_level++;
if (ssg->env_level == 0x20) {
ssg->env_level = 0;
if (ssg->env_alt) {
ssg->env_att = !ssg->env_att;
}
if (ssg->env_hld) {
ssg->env_level = 0x1f;
ssg->env_holding = true;
}
}
}
}
//int16_t out = 0;
for (int ch = 0; ch < 3; ch++) {
buf[i*4+ch] = 0;
if (++ssg->ch[ch].tone_counter >= opna_ssg_tone_period(ssg, ch)) {
ssg->ch[ch].tone_counter = 0;
ssg->ch[ch].out = !ssg->ch[ch].out;
}
if (!ssg->ymf288) {
// OPNA output level + HPF
int32_t previntmp = 0;
if (opna_ssg_tone_out(ssg, ch)) {
int level = opna_ssg_channel_level(ssg, ch);
previntmp = voltable[level]*5;
}
previntmp *= COEFF;
ssg->prevout[ch] = previntmp - ssg->previn[ch] + ((((int64_t)COEFF)*ssg->prevout[ch]) >> COEFFSH);
ssg->previn[ch] = previntmp;
buf[i*4+ch] = ssg->prevout[ch] >> COEFFSH;
} else {
// YMF288
int level = opna_ssg_channel_level(ssg, ch);
if (!opna_ssg_tone_silent(ssg, ch)) {
buf[i*4+ch] = (opna_ssg_tone_out_ymf288(ssg, ch) ? voltable[level] : -voltable[level]);
} else {
buf[i*4+ch] = voltable[level]*2;
}
}
}
//buf[i] = out / 2;
}
}
#define BUFINDEX(n) ((((resampler->index)>>1)+n)&(OPNA_SSG_SINCTABLELEN-1))
void opna_ssg_mix_55466(
struct opna_ssg *ssg, struct opna_ssg_resampler *resampler,
int16_t *buf, int samples,
struct oscillodata *oscillo, unsigned offset
) {
#ifdef LIBOPNA_ENABLE_OSCILLO
if (oscillo) {
for (unsigned c = 0; c < 3; c++) {
unsigned period = (opna_ssg_tone_period(ssg, c) << OSCILLO_OFFSET_SHIFT) * 2 * 32 / 144;
if (period) {
oscillo[c].offset += (samples << OSCILLO_OFFSET_SHIFT);
oscillo[c].offset %= period;
} else {
oscillo[c].offset = 0;
}
}
}
#else
(void)oscillo;
(void)offset;
#endif
unsigned level[3] = {0};
for (int i = 0; i < samples; i++) {
{
int ssg_samples = ((resampler->index + 9)>>1) - ((resampler->index)>>1);
int16_t ssgbuf[20];
opna_ssg_generate_raw(ssg, ssgbuf, ssg_samples);
for (int j = 0; j < ssg_samples; j++) {
resampler->buf[BUFINDEX(j)*4+0] = ssgbuf[j*4+0];
resampler->buf[BUFINDEX(j)*4+1] = ssgbuf[j*4+1];
resampler->buf[BUFINDEX(j)*4+2] = ssgbuf[j*4+2];
}
resampler->index += 9;
}
int32_t sample = 0;
resampler->index &= (1u<<(OPNA_SSG_SINCTABLEBIT+1))-1;
memcpy(resampler->buf + OPNA_SSG_SINCTABLELEN*4, resampler->buf, OPNA_SSG_SINCTABLELEN*4*sizeof(*resampler->buf));
int32_t outbuf[3];
if (!ssg->ymf288) {
// OPNA analog: bandlimited sinc resample
opna_ssg_sinc_calc_func(resampler->index, resampler->buf, outbuf);
for (int ch = 0; ch < 3; ch++) {
outbuf[ch] >>= 16;
outbuf[ch] *= 13000;
outbuf[ch] >>= 16;
outbuf[ch] *= ssg->mix;
outbuf[ch] >>= 16;
}
} else {
// YMF288: average of the samples (equivalent to FIR with rectangular function
for (int ch = 0; ch < 3; ch++) {
int ind = (resampler->index & 1) ? BUFINDEX(5) : BUFINDEX(0);
outbuf[ch] = resampler->buf[ind*4+ch];
for (int s = 0; s < 4; s++) {
outbuf[ch] += resampler->buf[BUFINDEX(s+1)*4+ch] * 2;
}
outbuf[ch] /= 9;
}
}
for (int ch = 0; ch < 3; ch++) {
#ifdef LIBOPNA_ENABLE_OSCILLO
if (oscillo) oscillo[ch].buf[offset+i] = outbuf[ch] << 1;
#endif
int32_t nlevel = outbuf[ch];
if (nlevel < 0) nlevel = -nlevel;
if (((unsigned)nlevel) > level[ch]) level[ch] = nlevel;
if (!(ssg->mask & (1<<ch))) sample += outbuf[ch];
}
int32_t lo = buf[i*2+0];
int32_t ro = buf[i*2+1];
lo += sample;
ro += sample;
if (lo < INT16_MIN) lo = INT16_MIN;
if (lo > INT16_MAX) lo = INT16_MAX;
if (ro < INT16_MIN) ro = INT16_MIN;
if (ro > INT16_MAX) ro = INT16_MAX;
buf[i*2+0] = lo;
buf[i*2+1] = ro;
}
#ifdef LIBOPNA_ENABLE_LEVELDATA
for (int c = 0; c < 3; c++) {
leveldata_update(&resampler->leveldata[c], level[c]);
}
#endif
}
#undef BUFINDEX
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