gzdoom-gles/libraries/opnmidi/chips/np2/fmgen_psg.cpp

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// ---------------------------------------------------------------------------
// PSG Sound Implementation
// Copyright (C) cisc 1997, 1999.
// ---------------------------------------------------------------------------
// $Id: psg.cpp,v 1.10 2002/05/15 21:38:01 cisc Exp $
#include "fmgen_headers.h"
#include "fmgen_misc.h"
#include "fmgen_psg.h"
// ---------------------------------------------------------------------------
// コンストラクタ・デストラクタ
//
PSG::PSG()
{
SetVolume(0);
MakeNoiseTable();
Reset();
mask = 0x3f;
}
PSG::~PSG()
{
}
// ---------------------------------------------------------------------------
// PSG を初期化する(RESET)
//
void PSG::Reset()
{
for (int i=0; i<14; i++)
SetReg(i, 0);
SetReg(7, 0xff);
SetReg(14, 0xff);
SetReg(15, 0xff);
}
// ---------------------------------------------------------------------------
// クロック周波数の設定
//
void PSG::SetClock(int clock, int rate)
{
tperiodbase = int((1 << toneshift ) / 4.0 * clock / rate);
eperiodbase = int((1 << envshift ) / 4.0 * clock / rate);
nperiodbase = int((1 << noiseshift) / 4.0 * clock / rate);
// 各データの更新
int tmp;
tmp = ((reg[0] + reg[1] * 256) & 0xfff);
speriod[0] = tmp ? tperiodbase / tmp : tperiodbase;
tmp = ((reg[2] + reg[3] * 256) & 0xfff);
speriod[1] = tmp ? tperiodbase / tmp : tperiodbase;
tmp = ((reg[4] + reg[5] * 256) & 0xfff);
speriod[2] = tmp ? tperiodbase / tmp : tperiodbase;
tmp = reg[6] & 0x1f;
nperiod = tmp ? nperiodbase / tmp / 2 : nperiodbase / 2;
tmp = ((reg[11] + reg[12] * 256) & 0xffff);
eperiod = tmp ? eperiodbase / tmp : eperiodbase * 2;
}
// ---------------------------------------------------------------------------
// ノイズテーブルを作成する
//
void PSG::MakeNoiseTable()
{
if (!noisetable[0])
{
int noise = 14321;
for (int i=0; i<noisetablesize; i++)
{
int n = 0;
for (int j=0; j<32; j++)
{
n = n * 2 + (noise & 1);
noise = (noise >> 1) | (((noise << 14) ^ (noise << 16)) & 0x10000);
}
noisetable[i] = n;
}
}
}
// ---------------------------------------------------------------------------
// 出力テーブルを作成
// 素直にテーブルで持ったほうが省スペース。
//
void PSG::SetVolume(int volume)
{
double base = 0x4000 / 3.0 * pow(10.0, volume / 40.0);
for (int i=31; i>=2; i--)
{
EmitTable[i] = int(base);
base /= 1.189207115;
}
EmitTable[1] = 0;
EmitTable[0] = 0;
MakeEnvelopTable();
SetChannelMask(~mask);
}
void PSG::SetChannelMask(int c)
{
mask = ~c;
for (int i=0; i<3; i++)
olevel[i] = mask & (1 << i) ? EmitTable[(reg[8+i] & 15) * 2 + 1] : 0;
}
// ---------------------------------------------------------------------------
// エンベロープ波形テーブル
//
void PSG::MakeEnvelopTable()
{
// 0 lo 1 up 2 down 3 hi
static uint8 table1[16*2] =
{
2,0, 2,0, 2,0, 2,0, 1,0, 1,0, 1,0, 1,0,
2,2, 2,0, 2,1, 2,3, 1,1, 1,3, 1,2, 1,0,
};
static uint8 table2[4] = { 0, 0, 31, 31 };
static int8 table3[4] = { 0, 1, -1, 0 };
uint* ptr = enveloptable[0];
for (int i=0; i<16*2; i++)
{
uint8 v = table2[table1[i]];
for (int j=0; j<32; j++)
{
*ptr++ = EmitTable[v];
v += table3[table1[i]];
}
}
}
// ---------------------------------------------------------------------------
// PSG のレジスタに値をセットする
// regnum レジスタの番号 (0 - 15)
// data セットする値
//
void PSG::SetReg(uint regnum, uint8 data)
{
if (regnum < 0x10)
{
reg[regnum] = data;
switch (regnum)
{
int tmp;
case 0: // ChA Fine Tune
case 1: // ChA Coarse Tune
tmp = ((reg[0] + reg[1] * 256) & 0xfff);
speriod[0] = tmp ? tperiodbase / tmp : tperiodbase;
break;
case 2: // ChB Fine Tune
case 3: // ChB Coarse Tune
tmp = ((reg[2] + reg[3] * 256) & 0xfff);
speriod[1] = tmp ? tperiodbase / tmp : tperiodbase;
break;
case 4: // ChC Fine Tune
case 5: // ChC Coarse Tune
tmp = ((reg[4] + reg[5] * 256) & 0xfff);
speriod[2] = tmp ? tperiodbase / tmp : tperiodbase;
break;
case 6: // Noise generator control
data &= 0x1f;
nperiod = data ? nperiodbase / data : nperiodbase;
break;
case 8:
olevel[0] = mask & 1 ? EmitTable[(data & 15) * 2 + 1] : 0;
break;
case 9:
olevel[1] = mask & 2 ? EmitTable[(data & 15) * 2 + 1] : 0;
break;
case 10:
olevel[2] = mask & 4 ? EmitTable[(data & 15) * 2 + 1] : 0;
break;
case 11: // Envelop period
case 12:
tmp = ((reg[11] + reg[12] * 256) & 0xffff);
eperiod = tmp ? eperiodbase / tmp : eperiodbase * 2;
break;
case 13: // Envelop shape
ecount = 0;
envelop = enveloptable[data & 15];
break;
}
}
}
// ---------------------------------------------------------------------------
void PSG::DataSave(struct PSGData* data) {
memcpy(data->reg, reg, 16);
memcpy(data->olevel, olevel, sizeof(uint) * 6);
memcpy(data->scount, scount, sizeof(uint32) * 3);
memcpy(data->speriod, speriod, sizeof(uint32) * 3);
data->ecount = ecount;
data->eperiod = eperiod;
data->ncount = ncount;
data->nperiod = nperiod;
data->tperiodbase = tperiodbase;
data->eperiodbase = eperiodbase;
data->nperiodbase = nperiodbase;
data->volume = volume;
data->mask = mask;
}
// ---------------------------------------------------------------------------
void PSG::DataLoad(struct PSGData* data) {
memcpy(reg, data->reg, 16);
memcpy(olevel, data->olevel, sizeof(uint) * 6);
memcpy(scount, data->scount, sizeof(uint32) * 3);
memcpy(speriod, data->speriod, sizeof(uint32) * 3);
ecount = data->ecount;
eperiod = data->eperiod;
ncount = data->ncount;
nperiod = data->nperiod;
tperiodbase = data->tperiodbase;
eperiodbase = data->eperiodbase;
nperiodbase = data->nperiodbase;
volume = data->volume;
mask = data->mask;
}
// ---------------------------------------------------------------------------
//
//
inline void PSG::StoreSample(Sample& dest, int32 data)
{
if (sizeof(Sample) == 2)
dest = (Sample) Limit(dest + data, 0x7fff, -0x8000);
else
dest += data;
}
// ---------------------------------------------------------------------------
// PCM データを吐き出す(2ch)
// dest PCM データを展開するポインタ
// nsamples 展開する PCM のサンプル数
//
void PSG::Mix(Sample* dest, int nsamples)
{
uint8 chenable[3], nenable[3];
uint8 r7 = ~reg[7];
if ((r7 & 0x3f) | ((reg[8] | reg[9] | reg[10]) & 0x1f))
{
chenable[0] = (r7 & 0x01) && (speriod[0] <= (1 << toneshift));
chenable[1] = (r7 & 0x02) && (speriod[1] <= (1 << toneshift));
chenable[2] = (r7 & 0x04) && (speriod[2] <= (1 << toneshift));
nenable[0] = (r7 >> 3) & 1;
nenable[1] = (r7 >> 4) & 1;
nenable[2] = (r7 >> 5) & 1;
int noise, sample;
uint env;
uint* p1 = ((mask & 1) && (reg[ 8] & 0x10)) ? &env : &olevel[0];
uint* p2 = ((mask & 2) && (reg[ 9] & 0x10)) ? &env : &olevel[1];
uint* p3 = ((mask & 4) && (reg[10] & 0x10)) ? &env : &olevel[2];
#define SCOUNT(ch) (scount[ch] >> (toneshift+oversampling))
if (p1 != &env && p2 != &env && p3 != &env)
{
// エンベロープ無し
if ((r7 & 0x38) == 0)
{
// ノイズ無し
for (int i=0; i<nsamples; i++)
{
sample = 0;
for (int j=0; j < (1 << oversampling); j++)
{
int x, y, z;
x = (SCOUNT(0) & chenable[0]) - 1;
sample += (olevel[0] + x) ^ x;
scount[0] += speriod[0];
y = (SCOUNT(1) & chenable[1]) - 1;
sample += (olevel[1] + y) ^ y;
scount[1] += speriod[1];
z = (SCOUNT(2) & chenable[2]) - 1;
sample += (olevel[2] + z) ^ z;
scount[2] += speriod[2];
}
sample /= (1 << oversampling);
StoreSample(dest[0], sample);
StoreSample(dest[1], sample);
dest += 2;
}
}
else
{
// ノイズ有り
for (int i=0; i<nsamples; i++)
{
sample = 0;
for (int j=0; j < (1 << oversampling); j++)
{
#ifdef _M_IX86
noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
>> (ncount >> (noiseshift+oversampling+1));
#else
noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
>> (ncount >> (noiseshift+oversampling+1) & 31);
#endif
ncount += nperiod;
int x, y, z;
x = ((SCOUNT(0) & chenable[0]) | (nenable[0] & noise)) - 1; // 0 or -1
sample += (olevel[0] + x) ^ x;
scount[0] += speriod[0];
y = ((SCOUNT(1) & chenable[1]) | (nenable[1] & noise)) - 1;
sample += (olevel[1] + y) ^ y;
scount[1] += speriod[1];
z = ((SCOUNT(2) & chenable[2]) | (nenable[2] & noise)) - 1;
sample += (olevel[2] + z) ^ z;
scount[2] += speriod[2];
}
sample /= (1 << oversampling);
StoreSample(dest[0], sample);
StoreSample(dest[1], sample);
dest += 2;
}
}
// エンベロープの計算をさぼった帳尻あわせ
ecount = (ecount >> 8) + (eperiod >> (8-oversampling)) * nsamples;
if (ecount >= (1 << (envshift+6+oversampling-8)))
{
if ((reg[0x0d] & 0x0b) != 0x0a)
ecount |= (1 << (envshift+5+oversampling-8));
ecount &= (1 << (envshift+6+oversampling-8)) - 1;
}
ecount <<= 8;
}
else
{
// エンベロープあり
for (int i=0; i<nsamples; i++)
{
sample = 0;
for (int j=0; j < (1 << oversampling); j++)
{
env = envelop[ecount >> (envshift+oversampling)];
ecount += eperiod;
if (ecount >= (1 << (envshift+6+oversampling)))
{
if ((reg[0x0d] & 0x0b) != 0x0a)
ecount |= (1 << (envshift+5+oversampling));
ecount &= (1 << (envshift+6+oversampling)) - 1;
}
#ifdef _M_IX86
noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
>> (ncount >> (noiseshift+oversampling+1));
#else
noise = noisetable[(ncount >> (noiseshift+oversampling+6)) & (noisetablesize-1)]
>> (ncount >> (noiseshift+oversampling+1) & 31);
#endif
ncount += nperiod;
int x, y, z;
x = ((SCOUNT(0) & chenable[0]) | (nenable[0] & noise)) - 1; // 0 or -1
sample += (*p1 + x) ^ x;
scount[0] += speriod[0];
y = ((SCOUNT(1) & chenable[1]) | (nenable[1] & noise)) - 1;
sample += (*p2 + y) ^ y;
scount[1] += speriod[1];
z = ((SCOUNT(2) & chenable[2]) | (nenable[2] & noise)) - 1;
sample += (*p3 + z) ^ z;
scount[2] += speriod[2];
}
sample /= (1 << oversampling);
StoreSample(dest[0], sample);
StoreSample(dest[1], sample);
dest += 2;
}
}
}
}
// ---------------------------------------------------------------------------
// テーブル
//
uint PSG::noisetable[noisetablesize] = { 0, };
int PSG::EmitTable[0x20] = { -1, };
uint PSG::enveloptable[16][64] = { {0, } };