ref: 299e1c5abf804e2e249c4f77b82fb7949a3f9d7b
dir: /opl/fmopl.c/
/* This file is derived from fmopl.cpp from ScummVM.
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* LGPL licensed version of MAMEs fmopl (V0.37a modified) by
* Tatsuyuki Satoh. Included from LGPL'ed AdPlug.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <math.h>
#include "fmopl.h"
#define PI 3.1415926539
#define CLIP(value, min, max) \
( (value) < (min) ? (min) : \
(value) > (max) ? (max) : (value) )
/* -------------------- preliminary define section --------------------- */
/* attack/decay rate time rate */
#define OPL_ARRATE 141280 /* RATE 4 = 2826.24ms @ 3.6MHz */
#define OPL_DRRATE 1956000 /* RATE 4 = 39280.64ms @ 3.6MHz */
#define FREQ_BITS 24 /* frequency turn */
/* counter bits = 20 , octerve 7 */
#define FREQ_RATE (1<<(FREQ_BITS-20))
#define TL_BITS (FREQ_BITS+2)
/* final output shift , limit minimum and maximum */
#define OPL_OUTSB (TL_BITS+3-16) /* OPL output final shift 16bit */
#define OPL_MAXOUT (0x7fff<<OPL_OUTSB)
#define OPL_MINOUT (-0x8000<<OPL_OUTSB)
/* -------------------- quality selection --------------------- */
/* sinwave entries */
/* used static memory = SIN_ENT * 4 (byte) */
#define SIN_ENT_SHIFT 11
#define SIN_ENT (1<<SIN_ENT_SHIFT)
/* output level entries (envelope,sinwave) */
/* envelope counter lower bits */
static int ENV_BITS;
/* envelope output entries */
static int EG_ENT;
/* used dynamic memory = EG_ENT*4*4(byte)or EG_ENT*6*4(byte) */
/* used static memory = EG_ENT*4 (byte) */
static int EG_OFF; /* OFF */
static int EG_DED;
static int EG_DST; /* DECAY START */
static int EG_AED;
#define EG_AST 0 /* ATTACK START */
#define EG_STEP (96.0/EG_ENT) /* OPL is 0.1875 dB step */
/* LFO table entries */
#define VIB_ENT 512
#define VIB_SHIFT (32-9)
#define AMS_ENT 512
#define AMS_SHIFT (32-9)
#define VIB_RATE_SHIFT 8
#define VIB_RATE (1<<VIB_RATE_SHIFT)
/* -------------------- local defines , macros --------------------- */
/* register number to channel number , slot offset */
#define SLOT1 0
#define SLOT2 1
/* envelope phase */
#define ENV_MOD_RR 0x00
#define ENV_MOD_DR 0x01
#define ENV_MOD_AR 0x02
/* -------------------- tables --------------------- */
static const int slot_array[32] = {
0, 2, 4, 1, 3, 5,-1,-1,
6, 8,10, 7, 9,11,-1,-1,
12,14,16,13,15,17,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1
};
static uint32_t KSL_TABLE[8 * 16];
static const double KSL_TABLE_SEED[8 * 16] = {
/* OCT 0 */
0.000, 0.000, 0.000, 0.000,
0.000, 0.000, 0.000, 0.000,
0.000, 0.000, 0.000, 0.000,
0.000, 0.000, 0.000, 0.000,
/* OCT 1 */
0.000, 0.000, 0.000, 0.000,
0.000, 0.000, 0.000, 0.000,
0.000, 0.750, 1.125, 1.500,
1.875, 2.250, 2.625, 3.000,
/* OCT 2 */
0.000, 0.000, 0.000, 0.000,
0.000, 1.125, 1.875, 2.625,
3.000, 3.750, 4.125, 4.500,
4.875, 5.250, 5.625, 6.000,
/* OCT 3 */
0.000, 0.000, 0.000, 1.875,
3.000, 4.125, 4.875, 5.625,
6.000, 6.750, 7.125, 7.500,
7.875, 8.250, 8.625, 9.000,
/* OCT 4 */
0.000, 0.000, 3.000, 4.875,
6.000, 7.125, 7.875, 8.625,
9.000, 9.750, 10.125, 10.500,
10.875, 11.250, 11.625, 12.000,
/* OCT 5 */
0.000, 3.000, 6.000, 7.875,
9.000, 10.125, 10.875, 11.625,
12.000, 12.750, 13.125, 13.500,
13.875, 14.250, 14.625, 15.000,
/* OCT 6 */
0.000, 6.000, 9.000, 10.875,
12.000, 13.125, 13.875, 14.625,
15.000, 15.750, 16.125, 16.500,
16.875, 17.250, 17.625, 18.000,
/* OCT 7 */
0.000, 9.000, 12.000, 13.875,
15.000, 16.125, 16.875, 17.625,
18.000, 18.750, 19.125, 19.500,
19.875, 20.250, 20.625, 21.000
};
/* sustain level table (3db per step) */
/* 0 - 15: 0, 3, 6, 9,12,15,18,21,24,27,30,33,36,39,42,93 (dB)*/
static int SL_TABLE[16];
static const uint32_t SL_TABLE_SEED[16] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 31
};
#define TL_MAX (EG_ENT * 2) /* limit(tl + ksr + envelope) + sinwave */
/* TotalLevel : 48 24 12 6 3 1.5 0.75 (dB) */
/* TL_TABLE[ 0 to TL_MAX ] : plus section */
/* TL_TABLE[ TL_MAX to TL_MAX+TL_MAX-1 ] : minus section */
static int *TL_TABLE;
/* pointers to TL_TABLE with sinwave output offset */
static int **SIN_TABLE;
/* LFO table */
static int *AMS_TABLE;
static int *VIB_TABLE;
/* envelope output curve table */
/* attack + decay + OFF */
//static int ENV_CURVE[2*EG_ENT+1];
//static int ENV_CURVE[2 * 4096 + 1]; // to keep it static ...
static int *ENV_CURVE;
/* multiple table */
#define ML(a) (int)(a * 2)
static const uint32_t MUL_TABLE[16]= {
/* 1/2, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15 */
ML(0.50), ML(1.00), ML(2.00), ML(3.00), ML(4.00), ML(5.00), ML(6.00), ML(7.00),
ML(8.00), ML(9.00), ML(10.00), ML(10.00),ML(12.00),ML(12.00),ML(15.00),ML(15.00)
};
#undef ML
/* dummy attack / decay rate ( when rate == 0 ) */
static int RATE_0[16]=
{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
/* -------------------- static state --------------------- */
/* lock level of common table */
static int num_lock = 0;
/* work table */
static void *cur_chip = NULL; /* current chip point */
/* currenct chip state */
/* static OPLSAMPLE *bufL,*bufR; */
static OPL_CH *S_CH;
static OPL_CH *E_CH;
static OPL_SLOT *SLOT7_1, *SLOT7_2, *SLOT8_1, *SLOT8_2;
static int outd[1];
static int ams;
static int vib;
static int *ams_table;
static int *vib_table;
static int amsIncr;
static int vibIncr;
static int feedback2; /* connect for SLOT 2 */
/* --------------------- rebuild tables ------------------- */
#define ARRAYSIZE(x) (sizeof(x) / sizeof(*x))
#define SC_KSL(mydb) ((uint32_t) (mydb / (EG_STEP / 2)))
#define SC_SL(db) (int)(db * ((3 / EG_STEP) * (1 << ENV_BITS))) + EG_DST
void OPLBuildTables(int ENV_BITS_PARAM, int EG_ENT_PARAM) {
int i;
ENV_BITS = ENV_BITS_PARAM;
EG_ENT = EG_ENT_PARAM;
EG_OFF = ((2 * EG_ENT)<<ENV_BITS); /* OFF */
EG_DED = EG_OFF;
EG_DST = (EG_ENT << ENV_BITS); /* DECAY START */
EG_AED = EG_DST;
//EG_STEP = (96.0/EG_ENT);
for (i = 0; i < ARRAYSIZE(KSL_TABLE_SEED); i++)
KSL_TABLE[i] = SC_KSL(KSL_TABLE_SEED[i]);
for (i = 0; i < ARRAYSIZE(SL_TABLE_SEED); i++)
SL_TABLE[i] = SC_SL(SL_TABLE_SEED[i]);
}
#undef SC_KSL
#undef SC_SL
/* --------------------- subroutines --------------------- */
/* status set and IRQ handling */
static inline void OPL_STATUS_SET(FM_OPL *OPL, int flag) {
/* set status flag */
OPL->status |= flag;
if(!(OPL->status & 0x80)) {
if(OPL->status & OPL->statusmask) { /* IRQ on */
OPL->status |= 0x80;
/* callback user interrupt handler (IRQ is OFF to ON) */
if(OPL->IRQHandler)
(OPL->IRQHandler)(OPL->IRQParam,1);
}
}
}
/* status reset and IRQ handling */
static inline void OPL_STATUS_RESET(FM_OPL *OPL, int flag) {
/* reset status flag */
OPL->status &= ~flag;
if((OPL->status & 0x80)) {
if (!(OPL->status & OPL->statusmask)) {
OPL->status &= 0x7f;
/* callback user interrupt handler (IRQ is ON to OFF) */
if(OPL->IRQHandler) (OPL->IRQHandler)(OPL->IRQParam,0);
}
}
}
/* IRQ mask set */
static inline void OPL_STATUSMASK_SET(FM_OPL *OPL, int flag) {
OPL->statusmask = flag;
/* IRQ handling check */
OPL_STATUS_SET(OPL,0);
OPL_STATUS_RESET(OPL,0);
}
/* ----- key on ----- */
static inline void OPL_KEYON(OPL_SLOT *SLOT) {
/* sin wave restart */
SLOT->Cnt = 0;
/* set attack */
SLOT->evm = ENV_MOD_AR;
SLOT->evs = SLOT->evsa;
SLOT->evc = EG_AST;
SLOT->eve = EG_AED;
}
/* ----- key off ----- */
static inline void OPL_KEYOFF(OPL_SLOT *SLOT) {
if( SLOT->evm > ENV_MOD_RR) {
/* set envelope counter from envleope output */
// WORKAROUND: The Kyra engine does something very strange when
// starting a new song. For each channel:
//
// * The release rate is set to "fastest".
// * Any note is keyed off.
// * A very low-frequency note is keyed on.
//
// Usually, what happens next is that the real notes is keyed
// on immediately, in which case there's no problem.
//
// However, if the note is again keyed off (because the channel
// begins on a rest rather than a note), the envelope counter
// was moved from the very lowest point on the attack curve to
// the very highest point on the release curve.
//
// Again, this might not be a problem, if the release rate is
// still set to "fastest". But in many cases, it had already
// been increased. And, possibly because of inaccuracies in the
// envelope generator, that would cause the note to "fade out"
// for quite a long time.
//
// What we really need is a way to find the correct starting
// point for the envelope counter, and that may be what the
// commented-out line below is meant to do. For now, simply
// handle the pathological case.
if (SLOT->evm == ENV_MOD_AR && SLOT->evc == EG_AST)
SLOT->evc = EG_DED;
else if( !(SLOT->evc & EG_DST) )
//SLOT->evc = (ENV_CURVE[SLOT->evc>>ENV_BITS]<<ENV_BITS) + EG_DST;
SLOT->evc = EG_DST;
SLOT->eve = EG_DED;
SLOT->evs = SLOT->evsr;
SLOT->evm = ENV_MOD_RR;
}
}
/* ---------- calcrate Envelope Generator & Phase Generator ---------- */
/* return : envelope output */
static inline uint32_t OPL_CALC_SLOT(OPL_SLOT *SLOT) {
/* calcrate envelope generator */
if((SLOT->evc += SLOT->evs) >= SLOT->eve) {
switch( SLOT->evm ) {
case ENV_MOD_AR: /* ATTACK -> DECAY1 */
/* next DR */
SLOT->evm = ENV_MOD_DR;
SLOT->evc = EG_DST;
SLOT->eve = SLOT->SL;
SLOT->evs = SLOT->evsd;
break;
case ENV_MOD_DR: /* DECAY -> SL or RR */
SLOT->evc = SLOT->SL;
SLOT->eve = EG_DED;
if(SLOT->eg_typ) {
SLOT->evs = 0;
} else {
SLOT->evm = ENV_MOD_RR;
SLOT->evs = SLOT->evsr;
}
break;
case ENV_MOD_RR: /* RR -> OFF */
SLOT->evc = EG_OFF;
SLOT->eve = EG_OFF + 1;
SLOT->evs = 0;
break;
}
}
/* calcrate envelope */
return SLOT->TLL + ENV_CURVE[SLOT->evc>>ENV_BITS] + (SLOT->ams ? ams : 0);
}
/* set algorythm connection */
static void set_algorythm(OPL_CH *CH) {
int *carrier = &outd[0];
CH->connect1 = CH->CON ? carrier : &feedback2;
CH->connect2 = carrier;
}
/* ---------- frequency counter for operater update ---------- */
static inline void CALC_FCSLOT(OPL_CH *CH, OPL_SLOT *SLOT) {
int ksr;
/* frequency step counter */
SLOT->Incr = CH->fc * SLOT->mul;
ksr = CH->kcode >> SLOT->KSR;
if( SLOT->ksr != ksr ) {
SLOT->ksr = ksr;
/* attack , decay rate recalcration */
SLOT->evsa = SLOT->AR[ksr];
SLOT->evsd = SLOT->DR[ksr];
SLOT->evsr = SLOT->RR[ksr];
}
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
}
/* set multi,am,vib,EG-TYP,KSR,mul */
static inline void set_mul(FM_OPL *OPL, int slot, int v) {
OPL_CH *CH = &OPL->P_CH[slot>>1];
OPL_SLOT *SLOT = &CH->SLOT[slot & 1];
SLOT->mul = MUL_TABLE[v & 0x0f];
SLOT->KSR = (v & 0x10) ? 0 : 2;
SLOT->eg_typ = (v & 0x20) >> 5;
SLOT->vib = (v & 0x40);
SLOT->ams = (v & 0x80);
CALC_FCSLOT(CH, SLOT);
}
/* set ksl & tl */
static inline void set_ksl_tl(FM_OPL *OPL, int slot, int v) {
OPL_CH *CH = &OPL->P_CH[slot>>1];
OPL_SLOT *SLOT = &CH->SLOT[slot & 1];
int ksl = v >> 6; /* 0 / 1.5 / 3 / 6 db/OCT */
SLOT->ksl = ksl ? 3-ksl : 31;
SLOT->TL = (int)((v & 0x3f) * (0.75 / EG_STEP)); /* 0.75db step */
if(!(OPL->mode & 0x80)) { /* not CSM latch total level */
SLOT->TLL = SLOT->TL + (CH->ksl_base >> SLOT->ksl);
}
}
/* set attack rate & decay rate */
static inline void set_ar_dr(FM_OPL *OPL, int slot, int v) {
OPL_CH *CH = &OPL->P_CH[slot>>1];
OPL_SLOT *SLOT = &CH->SLOT[slot & 1];
int ar = v >> 4;
int dr = v & 0x0f;
SLOT->AR = ar ? &OPL->AR_TABLE[ar << 2] : RATE_0;
SLOT->evsa = SLOT->AR[SLOT->ksr];
if(SLOT->evm == ENV_MOD_AR)
SLOT->evs = SLOT->evsa;
SLOT->DR = dr ? &OPL->DR_TABLE[dr<<2] : RATE_0;
SLOT->evsd = SLOT->DR[SLOT->ksr];
if(SLOT->evm == ENV_MOD_DR)
SLOT->evs = SLOT->evsd;
}
/* set sustain level & release rate */
static inline void set_sl_rr(FM_OPL *OPL, int slot, int v) {
OPL_CH *CH = &OPL->P_CH[slot>>1];
OPL_SLOT *SLOT = &CH->SLOT[slot & 1];
int sl = v >> 4;
int rr = v & 0x0f;
SLOT->SL = SL_TABLE[sl];
if(SLOT->evm == ENV_MOD_DR)
SLOT->eve = SLOT->SL;
SLOT->RR = &OPL->DR_TABLE[rr<<2];
SLOT->evsr = SLOT->RR[SLOT->ksr];
if(SLOT->evm == ENV_MOD_RR)
SLOT->evs = SLOT->evsr;
}
/* operator output calcrator */
#define OP_OUT(slot,env,con) slot->wavetable[((slot->Cnt + con)>>(24-SIN_ENT_SHIFT)) & (SIN_ENT-1)][env]
/* ---------- calcrate one of channel ---------- */
static inline void OPL_CALC_CH(OPL_CH *CH) {
uint32_t env_out;
OPL_SLOT *SLOT;
feedback2 = 0;
/* SLOT 1 */
SLOT = &CH->SLOT[SLOT1];
env_out=OPL_CALC_SLOT(SLOT);
if(env_out < (uint32_t)(EG_ENT - 1)) {
/* PG */
if(SLOT->vib)
SLOT->Cnt += (SLOT->Incr * vib) >> VIB_RATE_SHIFT;
else
SLOT->Cnt += SLOT->Incr;
/* connection */
if(CH->FB) {
int feedback1 = (CH->op1_out[0] + CH->op1_out[1]) >> CH->FB;
CH->op1_out[1] = CH->op1_out[0];
*CH->connect1 += CH->op1_out[0] = OP_OUT(SLOT, env_out, feedback1);
} else {
*CH->connect1 += OP_OUT(SLOT, env_out, 0);
}
} else {
CH->op1_out[1] = CH->op1_out[0];
CH->op1_out[0] = 0;
}
/* SLOT 2 */
SLOT = &CH->SLOT[SLOT2];
env_out=OPL_CALC_SLOT(SLOT);
if(env_out < (uint32_t)(EG_ENT - 1)) {
/* PG */
if(SLOT->vib)
SLOT->Cnt += (SLOT->Incr * vib) >> VIB_RATE_SHIFT;
else
SLOT->Cnt += SLOT->Incr;
/* connection */
outd[0] += OP_OUT(SLOT, env_out, feedback2);
}
}
/* ---------- calcrate rythm block ---------- */
#define WHITE_NOISE_db 6.0
static inline void OPL_CALC_RH(FM_OPL *OPL, OPL_CH *CH) {
uint32_t env_tam, env_sd, env_top, env_hh;
// This code used to do int(OPL->rnd.getRandomBit() * (WHITE_NOISE_db / EG_STEP)),
// but EG_STEP = 96.0/EG_ENT, and WHITE_NOISE_db=6.0. So, that's equivalent to
// int(OPL->rnd.getRandomBit() * EG_ENT/16). We know that EG_ENT is 4096, or 1024,
// or 128, so we can safely avoid any FP ops.
int whitenoise = (rand() & 1) * (EG_ENT>>4);
int tone8;
OPL_SLOT *SLOT;
int env_out;
/* BD : same as FM serial mode and output level is large */
feedback2 = 0;
/* SLOT 1 */
SLOT = &CH[6].SLOT[SLOT1];
env_out = OPL_CALC_SLOT(SLOT);
if(env_out < EG_ENT-1) {
/* PG */
if(SLOT->vib)
SLOT->Cnt += (SLOT->Incr * vib) >> VIB_RATE_SHIFT;
else
SLOT->Cnt += SLOT->Incr;
/* connection */
if(CH[6].FB) {
int feedback1 = (CH[6].op1_out[0] + CH[6].op1_out[1]) >> CH[6].FB;
CH[6].op1_out[1] = CH[6].op1_out[0];
feedback2 = CH[6].op1_out[0] = OP_OUT(SLOT, env_out, feedback1);
}
else {
feedback2 = OP_OUT(SLOT, env_out, 0);
}
} else {
feedback2 = 0;
CH[6].op1_out[1] = CH[6].op1_out[0];
CH[6].op1_out[0] = 0;
}
/* SLOT 2 */
SLOT = &CH[6].SLOT[SLOT2];
env_out = OPL_CALC_SLOT(SLOT);
if(env_out < EG_ENT-1) {
/* PG */
if(SLOT->vib)
SLOT->Cnt += (SLOT->Incr * vib) >> VIB_RATE_SHIFT;
else
SLOT->Cnt += SLOT->Incr;
/* connection */
outd[0] += OP_OUT(SLOT, env_out, feedback2) * 2;
}
// SD (17) = mul14[fnum7] + white noise
// TAM (15) = mul15[fnum8]
// TOP (18) = fnum6(mul18[fnum8]+whitenoise)
// HH (14) = fnum7(mul18[fnum8]+whitenoise) + white noise
env_sd = OPL_CALC_SLOT(SLOT7_2) + whitenoise;
env_tam =OPL_CALC_SLOT(SLOT8_1);
env_top = OPL_CALC_SLOT(SLOT8_2);
env_hh = OPL_CALC_SLOT(SLOT7_1) + whitenoise;
/* PG */
if(SLOT7_1->vib)
SLOT7_1->Cnt += (SLOT7_1->Incr * vib) >> (VIB_RATE_SHIFT-1);
else
SLOT7_1->Cnt += 2 * SLOT7_1->Incr;
if(SLOT7_2->vib)
SLOT7_2->Cnt += (CH[7].fc * vib) >> (VIB_RATE_SHIFT-3);
else
SLOT7_2->Cnt += (CH[7].fc * 8);
if(SLOT8_1->vib)
SLOT8_1->Cnt += (SLOT8_1->Incr * vib) >> VIB_RATE_SHIFT;
else
SLOT8_1->Cnt += SLOT8_1->Incr;
if(SLOT8_2->vib)
SLOT8_2->Cnt += ((CH[8].fc * 3) * vib) >> (VIB_RATE_SHIFT-4);
else
SLOT8_2->Cnt += (CH[8].fc * 48);
tone8 = OP_OUT(SLOT8_2,whitenoise,0 );
/* SD */
if(env_sd < (uint32_t)(EG_ENT - 1))
outd[0] += OP_OUT(SLOT7_1, env_sd, 0) * 8;
/* TAM */
if(env_tam < (uint32_t)(EG_ENT - 1))
outd[0] += OP_OUT(SLOT8_1, env_tam, 0) * 2;
/* TOP-CY */
if(env_top < (uint32_t)(EG_ENT - 1))
outd[0] += OP_OUT(SLOT7_2, env_top, tone8) * 2;
/* HH */
if(env_hh < (uint32_t)(EG_ENT-1))
outd[0] += OP_OUT(SLOT7_2, env_hh, tone8) * 2;
}
/* ----------- initialize time tabls ----------- */
static void init_timetables(FM_OPL *OPL, int ARRATE, int DRRATE) {
int i;
double rate;
/* make attack rate & decay rate tables */
for (i = 0; i < 4; i++)
OPL->AR_TABLE[i] = OPL->DR_TABLE[i] = 0;
for (i = 4; i <= 60; i++) {
rate = OPL->freqbase; /* frequency rate */
if(i < 60)
rate *= 1.0 + (i & 3) * 0.25; /* b0-1 : x1 , x1.25 , x1.5 , x1.75 */
rate *= 1 << ((i >> 2) - 1); /* b2-5 : shift bit */
rate *= (double)(EG_ENT << ENV_BITS);
OPL->AR_TABLE[i] = (int)(rate / ARRATE);
OPL->DR_TABLE[i] = (int)(rate / DRRATE);
}
for (i = 60; i < 76; i++) {
OPL->AR_TABLE[i] = EG_AED-1;
OPL->DR_TABLE[i] = OPL->DR_TABLE[60];
}
}
/* ---------- generic table initialize ---------- */
static int OPLOpenTable(void) {
int s,t;
double rate;
int i,j;
double pom;
/* allocate dynamic tables */
if((TL_TABLE = (int *)malloc(TL_MAX * 2 * sizeof(int))) == NULL)
return 0;
if((SIN_TABLE = (int **)malloc(SIN_ENT * 4 * sizeof(int *))) == NULL) {
free(TL_TABLE);
return 0;
}
if((AMS_TABLE = (int *)malloc(AMS_ENT * 2 * sizeof(int))) == NULL) {
free(TL_TABLE);
free(SIN_TABLE);
return 0;
}
if((VIB_TABLE = (int *)malloc(VIB_ENT * 2 * sizeof(int))) == NULL) {
free(TL_TABLE);
free(SIN_TABLE);
free(AMS_TABLE);
return 0;
}
/* make total level table */
for (t = 0; t < EG_ENT - 1 ; t++) {
rate = ((1 << TL_BITS) - 1) / pow(10.0, EG_STEP * t / 20); /* dB -> voltage */
TL_TABLE[ t] = (int)rate;
TL_TABLE[TL_MAX + t] = -TL_TABLE[t];
}
/* fill volume off area */
for (t = EG_ENT - 1; t < TL_MAX; t++) {
TL_TABLE[t] = TL_TABLE[TL_MAX + t] = 0;
}
/* make sinwave table (total level offet) */
/* degree 0 = degree 180 = off */
SIN_TABLE[0] = SIN_TABLE[SIN_ENT /2 ] = &TL_TABLE[EG_ENT - 1];
for (s = 1;s <= SIN_ENT / 4; s++) {
pom = sin(2 * PI * s / SIN_ENT); /* sin */
pom = 20 * log10(1 / pom); /* decibel */
j = (int) (pom / EG_STEP); /* TL_TABLE steps */
/* degree 0 - 90 , degree 180 - 90 : plus section */
SIN_TABLE[ s] = SIN_TABLE[SIN_ENT / 2 - s] = &TL_TABLE[j];
/* degree 180 - 270 , degree 360 - 270 : minus section */
SIN_TABLE[SIN_ENT / 2 + s] = SIN_TABLE[SIN_ENT - s] = &TL_TABLE[TL_MAX + j];
}
for (s = 0;s < SIN_ENT; s++) {
SIN_TABLE[SIN_ENT * 1 + s] = s < (SIN_ENT / 2) ? SIN_TABLE[s] : &TL_TABLE[EG_ENT];
SIN_TABLE[SIN_ENT * 2 + s] = SIN_TABLE[s % (SIN_ENT / 2)];
SIN_TABLE[SIN_ENT * 3 + s] = (s / (SIN_ENT / 4)) & 1 ? &TL_TABLE[EG_ENT] : SIN_TABLE[SIN_ENT * 2 + s];
}
ENV_CURVE = (int *)malloc(sizeof(int) * (2*EG_ENT+1));
/* envelope counter -> envelope output table */
for (i=0; i < EG_ENT; i++) {
/* ATTACK curve */
pom = pow(((double)(EG_ENT - 1 - i) / EG_ENT), 8) * EG_ENT;
/* if( pom >= EG_ENT ) pom = EG_ENT-1; */
ENV_CURVE[i] = (int)pom;
/* DECAY ,RELEASE curve */
ENV_CURVE[(EG_DST >> ENV_BITS) + i]= i;
}
/* off */
ENV_CURVE[EG_OFF >> ENV_BITS]= EG_ENT - 1;
/* make LFO ams table */
for (i=0; i < AMS_ENT; i++) {
pom = (1.0 + sin(2 * PI * i / AMS_ENT)) / 2; /* sin */
AMS_TABLE[i] = (int)((1.0 / EG_STEP) * pom); /* 1dB */
AMS_TABLE[AMS_ENT + i] = (int)((4.8 / EG_STEP) * pom); /* 4.8dB */
}
/* make LFO vibrate table */
for (i=0; i < VIB_ENT; i++) {
/* 100cent = 1seminote = 6% ?? */
pom = (double)VIB_RATE * 0.06 * sin(2 * PI * i / VIB_ENT); /* +-100sect step */
VIB_TABLE[i] = (int)(VIB_RATE + (pom * 0.07)); /* +- 7cent */
VIB_TABLE[VIB_ENT + i] = (int)(VIB_RATE + (pom * 0.14)); /* +-14cent */
}
return 1;
}
static void OPLCloseTable(void) {
free(TL_TABLE);
free(SIN_TABLE);
free(AMS_TABLE);
free(VIB_TABLE);
free(ENV_CURVE);
}
/* CSM Key Controll */
static inline void CSMKeyControll(OPL_CH *CH) {
OPL_SLOT *slot1 = &CH->SLOT[SLOT1];
OPL_SLOT *slot2 = &CH->SLOT[SLOT2];
/* all key off */
OPL_KEYOFF(slot1);
OPL_KEYOFF(slot2);
/* total level latch */
slot1->TLL = slot1->TL + (CH->ksl_base>>slot1->ksl);
slot1->TLL = slot1->TL + (CH->ksl_base>>slot1->ksl);
/* key on */
CH->op1_out[0] = CH->op1_out[1] = 0;
OPL_KEYON(slot1);
OPL_KEYON(slot2);
}
/* ---------- opl initialize ---------- */
static void OPL_initalize(FM_OPL *OPL) {
int fn;
/* frequency base */
OPL->freqbase = (OPL->rate) ? ((double)OPL->clock / OPL->rate) / 72 : 0;
/* Timer base time */
OPL->TimerBase = 1.0/((double)OPL->clock / 72.0 );
/* make time tables */
init_timetables(OPL, OPL_ARRATE, OPL_DRRATE);
/* make fnumber -> increment counter table */
for( fn=0; fn < 1024; fn++) {
OPL->FN_TABLE[fn] = (uint32_t)(OPL->freqbase * fn * FREQ_RATE * (1<<7) / 2);
}
/* LFO freq.table */
OPL->amsIncr = (int)(OPL->rate ? (double)AMS_ENT * (1 << AMS_SHIFT) / OPL->rate * 3.7 * ((double)OPL->clock/3600000) : 0);
OPL->vibIncr = (int)(OPL->rate ? (double)VIB_ENT * (1 << VIB_SHIFT) / OPL->rate * 6.4 * ((double)OPL->clock/3600000) : 0);
}
/* ---------- write a OPL registers ---------- */
void OPLWriteReg(FM_OPL *OPL, int r, int v) {
OPL_CH *CH;
int slot;
uint32_t block_fnum;
switch(r & 0xe0) {
case 0x00: /* 00-1f:controll */
switch(r & 0x1f) {
case 0x01:
/* wave selector enable */
if(OPL->type&OPL_TYPE_WAVESEL) {
OPL->wavesel = v & 0x20;
if(!OPL->wavesel) {
/* preset compatible mode */
int c;
for(c=0; c<OPL->max_ch; c++) {
OPL->P_CH[c].SLOT[SLOT1].wavetable = &SIN_TABLE[0];
OPL->P_CH[c].SLOT[SLOT2].wavetable = &SIN_TABLE[0];
}
}
}
return;
case 0x02: /* Timer 1 */
OPL->T[0] = (256-v) * 4;
break;
case 0x03: /* Timer 2 */
OPL->T[1] = (256-v) * 16;
return;
case 0x04: /* IRQ clear / mask and Timer enable */
if(v & 0x80) { /* IRQ flag clear */
OPL_STATUS_RESET(OPL, 0x7f);
} else { /* set IRQ mask ,timer enable*/
uint8_t st1 = v & 1;
uint8_t st2 = (v >> 1) & 1;
/* IRQRST,T1MSK,t2MSK,EOSMSK,BRMSK,x,ST2,ST1 */
OPL_STATUS_RESET(OPL, v & 0x78);
OPL_STATUSMASK_SET(OPL,((~v) & 0x78) | 0x01);
/* timer 2 */
if(OPL->st[1] != st2) {
double interval = st2 ? (double)OPL->T[1] * OPL->TimerBase : 0.0;
OPL->st[1] = st2;
if (OPL->TimerHandler) (OPL->TimerHandler)(OPL->TimerParam + 1, interval);
}
/* timer 1 */
if(OPL->st[0] != st1) {
double interval = st1 ? (double)OPL->T[0] * OPL->TimerBase : 0.0;
OPL->st[0] = st1;
if (OPL->TimerHandler) (OPL->TimerHandler)(OPL->TimerParam + 0, interval);
}
}
return;
}
break;
case 0x20: /* am,vib,ksr,eg type,mul */
slot = slot_array[r&0x1f];
if(slot == -1)
return;
set_mul(OPL,slot,v);
return;
case 0x40:
slot = slot_array[r&0x1f];
if(slot == -1)
return;
set_ksl_tl(OPL,slot,v);
return;
case 0x60:
slot = slot_array[r&0x1f];
if(slot == -1)
return;
set_ar_dr(OPL,slot,v);
return;
case 0x80:
slot = slot_array[r&0x1f];
if(slot == -1)
return;
set_sl_rr(OPL,slot,v);
return;
case 0xa0:
switch(r) {
case 0xbd:
/* amsep,vibdep,r,bd,sd,tom,tc,hh */
{
uint8_t rkey = OPL->rythm ^ v;
OPL->ams_table = &AMS_TABLE[v & 0x80 ? AMS_ENT : 0];
OPL->vib_table = &VIB_TABLE[v & 0x40 ? VIB_ENT : 0];
OPL->rythm = v & 0x3f;
if(OPL->rythm & 0x20) {
/* BD key on/off */
if(rkey & 0x10) {
if(v & 0x10) {
OPL->P_CH[6].op1_out[0] = OPL->P_CH[6].op1_out[1] = 0;
OPL_KEYON(&OPL->P_CH[6].SLOT[SLOT1]);
OPL_KEYON(&OPL->P_CH[6].SLOT[SLOT2]);
} else {
OPL_KEYOFF(&OPL->P_CH[6].SLOT[SLOT1]);
OPL_KEYOFF(&OPL->P_CH[6].SLOT[SLOT2]);
}
}
/* SD key on/off */
if(rkey & 0x08) {
if(v & 0x08)
OPL_KEYON(&OPL->P_CH[7].SLOT[SLOT2]);
else
OPL_KEYOFF(&OPL->P_CH[7].SLOT[SLOT2]);
}/* TAM key on/off */
if(rkey & 0x04) {
if(v & 0x04)
OPL_KEYON(&OPL->P_CH[8].SLOT[SLOT1]);
else
OPL_KEYOFF(&OPL->P_CH[8].SLOT[SLOT1]);
}
/* TOP-CY key on/off */
if(rkey & 0x02) {
if(v & 0x02)
OPL_KEYON(&OPL->P_CH[8].SLOT[SLOT2]);
else
OPL_KEYOFF(&OPL->P_CH[8].SLOT[SLOT2]);
}
/* HH key on/off */
if(rkey & 0x01) {
if(v & 0x01)
OPL_KEYON(&OPL->P_CH[7].SLOT[SLOT1]);
else
OPL_KEYOFF(&OPL->P_CH[7].SLOT[SLOT1]);
}
}
}
return;
default:
break;
}
/* keyon,block,fnum */
if((r & 0x0f) > 8)
return;
CH = &OPL->P_CH[r & 0x0f];
if(!(r&0x10)) { /* a0-a8 */
block_fnum = (CH->block_fnum & 0x1f00) | v;
} else { /* b0-b8 */
int keyon = (v >> 5) & 1;
block_fnum = ((v & 0x1f) << 8) | (CH->block_fnum & 0xff);
if(CH->keyon != keyon) {
if((CH->keyon=keyon)) {
CH->op1_out[0] = CH->op1_out[1] = 0;
OPL_KEYON(&CH->SLOT[SLOT1]);
OPL_KEYON(&CH->SLOT[SLOT2]);
} else {
OPL_KEYOFF(&CH->SLOT[SLOT1]);
OPL_KEYOFF(&CH->SLOT[SLOT2]);
}
}
}
/* update */
if(CH->block_fnum != block_fnum) {
int blockRv = 7 - (block_fnum >> 10);
int fnum = block_fnum & 0x3ff;
CH->block_fnum = block_fnum;
CH->ksl_base = KSL_TABLE[block_fnum >> 6];
CH->fc = OPL->FN_TABLE[fnum] >> blockRv;
CH->kcode = CH->block_fnum >> 9;
if((OPL->mode & 0x40) && CH->block_fnum & 0x100)
CH->kcode |=1;
CALC_FCSLOT(CH,&CH->SLOT[SLOT1]);
CALC_FCSLOT(CH,&CH->SLOT[SLOT2]);
}
return;
case 0xc0:
/* FB,C */
if((r & 0x0f) > 8)
return;
CH = &OPL->P_CH[r&0x0f];
{
int feedback = (v >> 1) & 7;
CH->FB = feedback ? (8 + 1) - feedback : 0;
CH->CON = v & 1;
set_algorythm(CH);
}
return;
case 0xe0: /* wave type */
slot = slot_array[r & 0x1f];
if(slot == -1)
return;
CH = &OPL->P_CH[slot>>1];
if(OPL->wavesel) {
CH->SLOT[slot&1].wavetable = &SIN_TABLE[(v & 0x03) * SIN_ENT];
}
return;
}
}
/* lock/unlock for common table */
static int OPL_LockTable(void) {
num_lock++;
if(num_lock>1)
return 0;
/* first time */
cur_chip = NULL;
/* allocate total level table (128kb space) */
if(!OPLOpenTable()) {
num_lock--;
return -1;
}
return 0;
}
static void OPL_UnLockTable(void) {
if(num_lock)
num_lock--;
if(num_lock)
return;
/* last time */
cur_chip = NULL;
OPLCloseTable();
}
/*******************************************************************************/
/* YM3812 local section */
/*******************************************************************************/
/* ---------- update one of chip ----------- */
void YM3812UpdateOne(FM_OPL *OPL, int16_t *buffer, int length, int interleave) {
int i;
int data;
int16_t *buf = buffer;
uint32_t amsCnt = OPL->amsCnt;
uint32_t vibCnt = OPL->vibCnt;
uint8_t rythm = OPL->rythm & 0x20;
OPL_CH *CH, *R_CH;
if((void *)OPL != cur_chip) {
cur_chip = (void *)OPL;
/* channel pointers */
S_CH = OPL->P_CH;
E_CH = &S_CH[9];
/* rythm slot */
SLOT7_1 = &S_CH[7].SLOT[SLOT1];
SLOT7_2 = &S_CH[7].SLOT[SLOT2];
SLOT8_1 = &S_CH[8].SLOT[SLOT1];
SLOT8_2 = &S_CH[8].SLOT[SLOT2];
/* LFO state */
amsIncr = OPL->amsIncr;
vibIncr = OPL->vibIncr;
ams_table = OPL->ams_table;
vib_table = OPL->vib_table;
}
R_CH = rythm ? &S_CH[6] : E_CH;
for(i = 0; i < length; i++) {
/* channel A channel B channel C */
/* LFO */
ams = ams_table[(amsCnt += amsIncr) >> AMS_SHIFT];
vib = vib_table[(vibCnt += vibIncr) >> VIB_SHIFT];
outd[0] = 0;
/* FM part */
for(CH=S_CH; CH < R_CH; CH++)
OPL_CALC_CH(CH);
/* Rythn part */
if(rythm)
OPL_CALC_RH(OPL, S_CH);
/* limit check */
data = CLIP(outd[0], OPL_MINOUT, OPL_MAXOUT);
/* store to sound buffer */
buf[i << interleave] = data >> OPL_OUTSB;
}
OPL->amsCnt = amsCnt;
OPL->vibCnt = vibCnt;
}
/* ---------- reset a chip ---------- */
void OPLResetChip(FM_OPL *OPL) {
int c,s;
int i;
/* reset chip */
OPL->mode = 0; /* normal mode */
OPL_STATUS_RESET(OPL, 0x7f);
/* reset with register write */
OPLWriteReg(OPL, 0x01,0); /* wabesel disable */
OPLWriteReg(OPL, 0x02,0); /* Timer1 */
OPLWriteReg(OPL, 0x03,0); /* Timer2 */
OPLWriteReg(OPL, 0x04,0); /* IRQ mask clear */
for(i = 0xff; i >= 0x20; i--)
OPLWriteReg(OPL,i,0);
/* reset OPerator parameter */
for(c = 0; c < OPL->max_ch ;c++ ) {
OPL_CH *CH = &OPL->P_CH[c];
/* OPL->P_CH[c].PAN = OPN_CENTER; */
for(s = 0; s < 2; s++ ) {
/* wave table */
CH->SLOT[s].wavetable = &SIN_TABLE[0];
/* CH->SLOT[s].evm = ENV_MOD_RR; */
CH->SLOT[s].evc = EG_OFF;
CH->SLOT[s].eve = EG_OFF + 1;
CH->SLOT[s].evs = 0;
}
}
}
/* ---------- Create a virtual YM3812 ---------- */
/* 'rate' is sampling rate and 'bufsiz' is the size of the */
FM_OPL *OPLCreate(int type, int clock, int rate) {
char *ptr;
FM_OPL *OPL;
int state_size;
int max_ch = 9; /* normaly 9 channels */
if( OPL_LockTable() == -1)
return NULL;
/* allocate OPL state space */
state_size = sizeof(FM_OPL);
state_size += sizeof(OPL_CH) * max_ch;
/* allocate memory block */
ptr = (char *)calloc(state_size, 1);
if(ptr == NULL)
return NULL;
/* clear */
memset(ptr, 0, state_size);
OPL = (FM_OPL *)ptr; ptr += sizeof(FM_OPL);
OPL->P_CH = (OPL_CH *)ptr; ptr += sizeof(OPL_CH) * max_ch;
/* set channel state pointer */
OPL->type = type;
OPL->clock = clock;
OPL->rate = rate;
OPL->max_ch = max_ch;
/* init grobal tables */
OPL_initalize(OPL);
/* reset chip */
OPLResetChip(OPL);
return OPL;
}
/* ---------- Destroy one of vietual YM3812 ---------- */
void OPLDestroy(FM_OPL *OPL) {
OPL_UnLockTable();
free(OPL);
}
/* ---------- Option handlers ---------- */
void OPLSetTimerHandler(FM_OPL *OPL, OPL_TIMERHANDLER TimerHandler,int channelOffset) {
OPL->TimerHandler = TimerHandler;
OPL->TimerParam = channelOffset;
}
void OPLSetIRQHandler(FM_OPL *OPL, OPL_IRQHANDLER IRQHandler, int param) {
OPL->IRQHandler = IRQHandler;
OPL->IRQParam = param;
}
void OPLSetUpdateHandler(FM_OPL *OPL, OPL_UPDATEHANDLER UpdateHandler,int param) {
OPL->UpdateHandler = UpdateHandler;
OPL->UpdateParam = param;
}
/* ---------- YM3812 I/O interface ---------- */
int OPLWrite(FM_OPL *OPL,int a,int v) {
if(!(a & 1)) { /* address port */
OPL->address = v & 0xff;
} else { /* data port */
if(OPL->UpdateHandler)
OPL->UpdateHandler(OPL->UpdateParam,0);
OPLWriteReg(OPL, OPL->address,v);
}
return OPL->status >> 7;
}
unsigned char OPLRead(FM_OPL *OPL,int a) {
if(!(a & 1)) { /* status port */
return OPL->status & (OPL->statusmask | 0x80);
}
return 0;
}
int OPLTimerOver(FM_OPL *OPL, int c) {
if(c) { /* Timer B */
OPL_STATUS_SET(OPL, 0x20);
} else { /* Timer A */
OPL_STATUS_SET(OPL, 0x40);
/* CSM mode key,TL controll */
if(OPL->mode & 0x80) { /* CSM mode total level latch and auto key on */
int ch;
if(OPL->UpdateHandler)
OPL->UpdateHandler(OPL->UpdateParam,0);
for(ch = 0; ch < 9; ch++)
CSMKeyControll(&OPL->P_CH[ch]);
}
}
/* reload timer */
if (OPL->TimerHandler)
(OPL->TimerHandler)(OPL->TimerParam + c, (double)OPL->T[c] * OPL->TimerBase);
return OPL->status >> 7;
}
FM_OPL *makeAdlibOPL(int rate) {
// We need to emulate one YM3812 chip
int env_bits = FMOPL_ENV_BITS_HQ;
int eg_ent = FMOPL_EG_ENT_HQ;
OPLBuildTables(env_bits, eg_ent);
return OPLCreate(OPL_TYPE_YM3812, 3579545, rate);
}