scummvm/engines/sky/music/adlibchannel.cpp
2014-02-18 02:39:38 +01:00

312 lines
10 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* 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.
*
*/
#include "common/endian.h"
#include "common/textconsole.h"
#include "common/util.h"
#include "sky/music/adlibchannel.h"
#include "sky/sky.h"
namespace Sky {
AdLibChannel::AdLibChannel(FM_OPL *opl, uint8 *pMusicData, uint16 startOfData) {
_opl = opl;
_musicData = pMusicData;
_channelData.loopPoint = startOfData;
_channelData.eventDataPtr = startOfData;
_channelData.channelActive = true;
_channelData.tremoVibro = 0;
_channelData.assignedInstrument = 0xFF;
_channelData.channelVolume = 0x7F;
_channelData.nextEventTime = getNextEventTime();
_channelData.adlibChannelNumber = _channelData.lastCommand = _channelData.note =
_channelData.adlibReg1 = _channelData.adlibReg2 = _channelData.freqOffset = 0;
_channelData.frequency = 0;
_channelData.instrumentData = NULL;
uint16 instrumentDataLoc;
if (SkyEngine::_systemVars.gameVersion == 109) {
//instrumentDataLoc = (_musicData[0x11D0] << 8) | _musicData[0x11CF];
//_frequenceTable = (uint16 *)(_musicData + 0x835);
//_registerTable = _musicData + 0xE35;
//_opOutputTable = _musicData + 0xE47;
//_adlibRegMirror = _musicData + 0xF4A;
instrumentDataLoc = READ_LE_UINT16(_musicData + 0x1204);
_frequenceTable = (uint16 *)(_musicData + 0x868);
_registerTable = _musicData + 0xE68;
_opOutputTable = _musicData + 0xE7A;
_adlibRegMirror = _musicData + 0xF7D;
} else if (SkyEngine::_systemVars.gameVersion == 267) {
instrumentDataLoc = READ_LE_UINT16(_musicData + 0x11FB);
_frequenceTable = (uint16 *)(_musicData + 0x7F4);
_registerTable = _musicData + 0xDF4;
_opOutputTable = _musicData + 0xE06;
_adlibRegMirror = _musicData + 0xF55;
} else {
instrumentDataLoc = READ_LE_UINT16(_musicData + 0x1205);
_frequenceTable = (uint16 *)(_musicData + 0x7FE);
_registerTable = _musicData + 0xDFE;
_opOutputTable = _musicData + 0xE10;
_adlibRegMirror = _musicData + 0xF5F;
}
_instrumentMap = _musicData+instrumentDataLoc;
_instruments = (InstrumentStruct *)(_instrumentMap+0x80);
}
AdLibChannel::~AdLibChannel() {
stopNote();
}
bool AdLibChannel::isActive() {
return _channelData.channelActive;
}
void AdLibChannel::updateVolume(uint16 pVolume) {
// Do nothing. The mixer handles the music volume for us.
}
/* This class uses the same area for the register mirror as the original
asm driver did (_musicData[0xF5F..0x105E]), so the cache is indeed shared
by all instances of the class.
*/
void AdLibChannel::setRegister(uint8 regNum, uint8 value) {
if (_adlibRegMirror[regNum] != value) {
OPLWriteReg (_opl, regNum, value);
_adlibRegMirror[regNum] = value;
}
}
void AdLibChannel::stopNote() {
if (_channelData.note & 0x20) {
_channelData.note &= ~0x20;
setRegister(0xB0 | _channelData.adlibChannelNumber, _channelData.note);
}
}
int32 AdLibChannel::getNextEventTime() {
int32 retV = 0;
uint8 cnt, lVal = 0;
for (cnt = 0; cnt < 4; cnt++) {
lVal = _musicData[_channelData.eventDataPtr];
_channelData.eventDataPtr++;
retV = (retV << 7) | (lVal & 0x7F);
if (!(lVal & 0x80))
break;
}
if (lVal & 0x80) {
return -1; // should never happen
} else
return retV;
}
uint8 AdLibChannel::process(uint16 aktTime) {
if (!_channelData.channelActive) {
return 0;
}
uint8 returnVal = 0;
_channelData.nextEventTime -= aktTime;
uint8 opcode;
while ((_channelData.nextEventTime < 0) && (_channelData.channelActive)) {
opcode = _musicData[_channelData.eventDataPtr];
_channelData.eventDataPtr++;
if (opcode & 0x80) {
if (opcode == 0xFF) {
// dummy opcode
} else if (opcode >= 0x90) {
switch (opcode&0xF) {
case 0: com90_caseNoteOff(); break;
case 1: com90_stopChannel(); break;
case 2: com90_setupInstrument(); break;
case 3:
returnVal = com90_updateTempo();
break;
case 5: com90_getFreqOffset(); break;
case 6: com90_getChannelVolume(); break;
case 7: com90_getTremoVibro(); break;
case 8: com90_loopMusic(); break;
case 9: com90_keyOff(); break;
case 12: com90_setLoopPoint(); break;
default:
error("AdLibChannel: Unknown music opcode 0x%02X", opcode);
break;
}
} else {
// new adlib channel assignment
_channelData.adlibChannelNumber = opcode & 0xF;
_channelData.adlibReg1 = _registerTable[((opcode & 0xF) << 1) | 0];
_channelData.adlibReg2 = _registerTable[((opcode & 0xF) << 1) | 1];
}
} else {
_channelData.lastCommand = opcode;
stopNote();
// not sure why this "if" is necessary...either a bug in my
// code or a bug in the music data (section 1, music 2)
if (_channelData.instrumentData || _channelData.tremoVibro) {
setupInstrument(opcode);
opcode = _musicData[_channelData.eventDataPtr];
_channelData.eventDataPtr++;
setupChannelVolume(opcode);
} else
_channelData.eventDataPtr++;
}
if (_channelData.channelActive)
_channelData.nextEventTime += getNextEventTime();
}
return returnVal;
}
void AdLibChannel::setupInstrument(uint8 opcode) {
uint16 nextNote;
if (_channelData.tremoVibro) {
uint8 newInstrument = _instrumentMap[opcode];
if (newInstrument != _channelData.assignedInstrument) {
_channelData.assignedInstrument = newInstrument;
_channelData.instrumentData = _instruments + newInstrument;
adlibSetupInstrument();
}
_channelData.lastCommand = _channelData.instrumentData->bindedEffect;
nextNote = getNextNote(_channelData.lastCommand);
} else {
nextNote = getNextNote(opcode - 0x18 + _channelData.instrumentData->bindedEffect);
}
_channelData.frequency = nextNote;
setRegister(0xA0 | _channelData.adlibChannelNumber, (uint8)nextNote);
setRegister(0xB0 | _channelData.adlibChannelNumber, (uint8)((nextNote >> 8) | 0x20));
_channelData.note = (uint8)((nextNote >> 8) | 0x20);
}
void AdLibChannel::setupChannelVolume(uint8 volume) {
uint8 resultOp;
uint32 resVol = ((volume + 1) * (_channelData.instrumentData->totOutLev_Op2 + 1)) << 1;
resVol &= 0xFFFF;
resVol *= (_channelData.channelVolume + 1) << 1;
resVol >>= 16;
assert(resVol < 0x81);
resultOp = ((_channelData.instrumentData->scalingLevel << 6) & 0xC0) | _opOutputTable[resVol];
setRegister(0x40 | _channelData.adlibReg2, resultOp);
if (_channelData.instrumentData->feedBack & 1) {
resVol = ((volume + 1) * (_channelData.instrumentData->totOutLev_Op1 + 1)) << 1;
resVol &= 0xFFFF;
resVol *= (_channelData.channelVolume + 1) << 1;
resVol >>= 16;
} else
resVol = _channelData.instrumentData->totOutLev_Op1;
assert(resVol < 0x81);
resultOp = ((_channelData.instrumentData->scalingLevel << 2) & 0xC0) | _opOutputTable[resVol];
setRegister(0x40 | _channelData.adlibReg1, resultOp);
}
void AdLibChannel::adlibSetupInstrument() {
setRegister(0x60 | _channelData.adlibReg1, _channelData.instrumentData->ad_Op1);
setRegister(0x60 | _channelData.adlibReg2, _channelData.instrumentData->ad_Op2);
setRegister(0x80 | _channelData.adlibReg1, _channelData.instrumentData->sr_Op1);
setRegister(0x80 | _channelData.adlibReg2, _channelData.instrumentData->sr_Op2);
setRegister(0xE0 | _channelData.adlibReg1, _channelData.instrumentData->waveSelect_Op1);
setRegister(0xE0 | _channelData.adlibReg2, _channelData.instrumentData->waveSelect_Op2);
setRegister(0xC0 | _channelData.adlibChannelNumber, _channelData.instrumentData->feedBack);
setRegister(0x20 | _channelData.adlibReg1, _channelData.instrumentData->ampMod_Op1);
setRegister(0x20 | _channelData.adlibReg2, _channelData.instrumentData->ampMod_Op2);
}
uint16 AdLibChannel::getNextNote(uint8 param) {
int16 freqIndex = ((int16)_channelData.freqOffset) - 0x40;
if (freqIndex >= 0x3F)
freqIndex++;
freqIndex *= 2;
freqIndex += param << 6;
uint16 freqData = FROM_LE_16(_frequenceTable[freqIndex % 0x300]);
if ((freqIndex % 0x300 >= 0x1C0) || (freqIndex / 0x300 > 0)) {
return (((freqIndex / 0x300) - 1) << 10) + (freqData & 0x7FF);
} else {
// looks like a bug. dunno why. It's what the ASM code says.
return (uint16)(((int16)freqData) >> 1);
}
}
//- command 90h routines
void AdLibChannel::com90_caseNoteOff() {
if (_musicData[_channelData.eventDataPtr] == _channelData.lastCommand)
stopNote();
_channelData.eventDataPtr++;
}
void AdLibChannel::com90_stopChannel() {
stopNote();
_channelData.channelActive = false;
}
void AdLibChannel::com90_setupInstrument() {
_channelData.channelVolume = 0x7F;
_channelData.freqOffset = 0x40;
_channelData.assignedInstrument = _musicData[_channelData.eventDataPtr];
_channelData.eventDataPtr++;
_channelData.instrumentData = _instruments + _channelData.assignedInstrument;
adlibSetupInstrument();
}
uint8 AdLibChannel::com90_updateTempo() {
return _musicData[_channelData.eventDataPtr++];
}
void AdLibChannel::com90_getFreqOffset() {
_channelData.freqOffset = _musicData[_channelData.eventDataPtr++];
if (_channelData.note & 0x20) {
uint16 nextNote = getNextNote(
_channelData.lastCommand - 0x18 + _channelData.instrumentData->bindedEffect);
setRegister(0xA0 | _channelData.adlibChannelNumber, (uint8)nextNote);
setRegister(0xB0 | _channelData.adlibChannelNumber, (uint8)((nextNote >> 8) | 0x20));
_channelData.note = (uint8)(nextNote >> 8) | 0x20;
}
}
void AdLibChannel::com90_getChannelVolume() {
_channelData.channelVolume = _musicData[_channelData.eventDataPtr++];
}
void AdLibChannel::com90_getTremoVibro() {
_channelData.tremoVibro = _musicData[_channelData.eventDataPtr++];
}
void AdLibChannel::com90_loopMusic() {
_channelData.eventDataPtr = _channelData.loopPoint;
}
void AdLibChannel::com90_keyOff() {
stopNote();
}
void AdLibChannel::com90_setLoopPoint() {
_channelData.loopPoint = _channelData.eventDataPtr;
}
} // End of namespace Sky