MADS::Dragonsphere::ASound Class Reference

Inheritance diagram for MADS::Dragonsphere::ASound:

Public Member Functions
	ASound (Audio::Mixer *mixer, const Common::Path &filename, int dataOffset, int dataSize)
virtual int	stop () override
int	poll () override
void	noise () override
void	playSound (int offset)
void	setVolume (int volume) override
Public Member Functions inherited from MADS::SoundDriver
	SoundDriver (Audio::Mixer *mixer, const Common::Path &filename, int dataOffset, int dataSize)
virtual int	command (int commandId, int param)=0

Static Public Member Functions
static void	validate (bool isDemo)

Protected Types
typedef void(ASound::*	CallbackFunction) ()

Protected Member Functions
int	isMusicChannelsActive ()
int	isAnyChannelActive ()
void	scheduleCallback (CallbackFunction fn)
void	resetCallbackTimer (uint16 period)
void	resetCallbackTimerEx (uint16 counter, uint16 period)
void	setMusicIndex (uint16 idx)
uint16	getMusicIndex () const
void	setScriptVar (int idx, uint8 val)
void	write (uint8 reg, uint8 value)
uint16	getRandomNumber ()
void	adlib_channelOn (uint8 portIndex)
void	signalSoundPlaying ()
void	pollAllChannels ()
void	pollActiveChannel ()
bool	isSoundActive (byte *ptr) const
void	findFreeChannel (byte *soundData)
void	findFreeChannelFull (byte *soundData)
byte *	loadData (int offset)
int	command0 ()
int	command1 ()
int	command2 ()
int	command3 ()
int	command4 ()
int	command5 ()
int	command6 ()
int	command7 ()
int	command8 ()
virtual void	callFunction (uint16 offset)
int	command18 ()
Protected Member Functions inherited from MADS::SoundDriver
Common::MemoryReadStream	getDataStream (int offset) const

Protected Attributes
AdlibChannel	_channel0
AdlibChannel	_channel1
AdlibChannel	_channel2
AdlibChannel	_channel3
AdlibChannel	_channel4
AdlibChannel	_channel5
AdlibChannel	_channel6
AdlibChannel	_channel7
AdlibChannel	_channel8
AdlibChannel *	_channels [9]
uint8	_adlibPorts [0x100] = { 0 }
Common::Array< AdlibSample >	_samples
Protected Attributes inherited from MADS::SoundDriver
Audio::Mixer *	_mixer
Common::Array< byte >	_soundData
Common::Mutex	_driverMutex

Member Typedef Documentation

CallbackFunction

typedef void(ASound::* MADS::Dragonsphere::ASound::CallbackFunction) ()

protected

Member-function pointer type for deferred sound-loader callbacks.

Constructor & Destructor Documentation

ASound()

MADS::Dragonsphere::ASound::ASound	(	Audio::Mixer *	mixer,
		const Common::Path &	filename,
		int	dataOffset,
		int	dataSize
	)

Constructor.

Parameters

mixer	Mixer instance
filename	Path to the .DR1 (or equivalent) sound-driver file
dataOffset	Offset in the file of the data segment
dataSize	Size of the data segment

Member Function Documentation

isMusicChannelsActive()

int MADS::Dragonsphere::ASound::isMusicChannelsActive ( )

protected

Checks whether any of channels 0-6 (or 0-8 when _musicOnlyFlag is clear) have a non-zero _activeCount. Returns non-zero if sound is playing. This is 'sub_1061A' in the disassembly.

isAnyChannelActive()

int MADS::Dragonsphere::ASound::isAnyChannelActive ( )

protected

Like isMusicChannelsActive but scans all 9 channels unconditionally (clears the ch0-6-only flag first). This is 'sub_1064E'.

scheduleCallback()

void MADS::Dragonsphere::ASound::scheduleCallback ( CallbackFunction  fn )

inlineprotected

Schedule fn as the next deferred-load callback. Does NOT touch _callbackCounter or _callbackPeriod — those are preserved from the previous loader so the callback fires on the right beat. Cast the derived-class member-function pointer with reinterpret_cast.

resetCallbackTimer()

void MADS::Dragonsphere::ASound::resetCallbackTimer ( uint16  period )

inlineprotected

Arm the periodic timer and clear any pending callback pointer. Call at the head of every immediate-load function (symmetric counter/period).

resetCallbackTimerEx()

void MADS::Dragonsphere::ASound::resetCallbackTimerEx ( uint16  counter, uint16  period  )

inlineprotected

Arm the periodic timer with separate counter and period values. Used by command44 which sets counter=0x60 but period=0xE0.

setMusicIndex()

void MADS::Dragonsphere::ASound::setMusicIndex ( uint16  idx )

inlineprotected

Set the music-piece index (word_12370) read by command18.

getMusicIndex()

uint16 MADS::Dragonsphere::ASound::getMusicIndex ( ) const

inlineprotected

Read the current music-piece index.

setScriptVar()

void MADS::Dragonsphere::ASound::setScriptVar ( int  idx, uint8  val  )

inlineprotected

Write one script-variable register (byte_16A10[idx]).

write()

void MADS::Dragonsphere::ASound::write ( uint8  reg, uint8  value  )

protected

Writes (reg, value) to the OPL chip and updates the _adlibPorts shadow array so subsequent reads return the last-written value.

getRandomNumber()

uint16 MADS::Dragonsphere::ASound::getRandomNumber ( )

protected

Updates and returns _randomSeed using a simple linear-feedback shift.

adlib_channelOn()

void MADS::Dragonsphere::ASound::adlib_channelOn ( uint8  portIndex )

protected

Restores one OPL operator by re-writing the value already stored in the _adlibPorts shadow array. command7 uses this to resume playback after a command6 pause without recalculating any TL values. 'portIndex' is the operator register index into _adlibPorts.

signalSoundPlaying()

void MADS::Dragonsphere::ASound::signalSoundPlaying ( )

protected

Sets _pollResult and _resultFlag to indicate that sound is playing.

pollAllChannels()

void MADS::Dragonsphere::ASound::pollAllChannels ( )

protected

Iterates over all 9 channels, sets _activeChannelPtr / _activeChannelNumber, and calls pollActiveChannel for each one.

pollActiveChannel()

void MADS::Dragonsphere::ASound::pollActiveChannel ( )

protected

Per-channel bytecode interpreter, called once per frame per active channel.

Sound data is a sequence of (note, duration) byte pairs plus command bytes with the high bit set (0x80-0xFF). The upper nibble of a command byte (after masking out the high bit) selects one of seven opcode groups:

0x0_ -> opcodes1 (patch/velocity/volume/vibrato/transpose/arpeggio) 0x1_ -> opcodes2 (inner/outer loop control, restart, branch/call) 0x2_ -> opcodes3 (tempo, script-variable arithmetic, call-by-address) 0x3_ -> opcodes4 (script-variable load/store/copy/inc/dec) 0x4_ -> opcodes5 (script-variable ALU: add/sub/mul/div with imm or var) 0x5_ -> opcodes6 (extended: random-range, indexed table read/write) 0x6_ -> opcodes7 (driver-level calls: command dispatch, etc.)

The lower nibble is passed as the sub-opcode to each group handler. Note bytes (high bit clear) consume one duration tick per call.

isSoundActive()

bool MADS::Dragonsphere::ASound::isSoundActive ( byte *  ptr ) const

protected

Returns true if the sound data block at 'ptr' is already playing.

findFreeChannel()

void MADS::Dragonsphere::ASound::findFreeChannel ( byte *  soundData )

protected

Scans channels 0-6 for an empty slot (_activeCount == 0) and calls load() on the first one found. Falls through to findFreeChannelFull for channels 6-8 when _findChannelMode != 1.

findFreeChannelFull()

void MADS::Dragonsphere::ASound::findFreeChannelFull ( byte *  soundData )

protected

Extends the search to channels 7-8, then checks for pending-stop channels (which can be pre-empted), working in reverse priority order (ch8, ch7, ch6 ... ch0).

loadData()

byte* MADS::Dragonsphere::ASound::loadData ( int  offset )

inlineprotected

Returns a pointer to the sound data at the given offset.

command0()

int MADS::Dragonsphere::ASound::command0 ( )

protected

command0: Full hardware reset.

1. Reset all 9 channels.
2. Mute all operator TL registers (0x40-0x55) to 0x3F.
3. Zero remaining operator registers (0x60-0xFF and 0x01-0x3F).
4. Write Waveform Select Enable (register 0x01 = 0x20).
5. Reset the tick callback.

command1()

int MADS::Dragonsphere::ASound::command1 ( )

protected

command1: Fade out all channels. Calls command3 (fade music channels 0-6) then command5 (fade SFX 7-8).

command2()

int MADS::Dragonsphere::ASound::command2 ( )

protected

command2: Fade out music channels 0-6. Calls AdlibChannel::setPtr2 on each, redirecting to the null stream and arming a one-step fade.

command3()

int MADS::Dragonsphere::ASound::command3 ( )

protected

command3: Fade out music channels 0-6 with pending-stop. Calls AdlibChannel::enable on channels 0-6.

command4()

int MADS::Dragonsphere::ASound::command4 ( )

protected

command4: Fade out SFX channels 7-8. Calls AdlibChannel::setPtr2 on channels 7 and 8.

command5()

int MADS::Dragonsphere::ASound::command5 ( )

protected

command5: Stop SFX channels 7-8 with pending-stop flag. Calls AdlibChannel::enable on channels 7 and 8, letting each channel finish its current OPL envelope before going idle.

command6()

int MADS::Dragonsphere::ASound::command6 ( )

protected

command6: Pause playback. Saves each channel's _freqSweepCounter into _savedSweepCounter, zeroes _freqSweepCounter on all channels, then mutes all 22 operator TL registers (the byte_1239B table covers all operator slots 0x40-0x55). Sets _isDisabled to prevent further updates.

command7()

int MADS::Dragonsphere::ASound::command7 ( )

protected

command7: Resume playback. Restores operator volumes for all channels from _adlibPorts shadow, copies _savedSweepCounter back to _freqSweepCounter on all channels, signals sound playing if any channel was active, then clears _isDisabled.

command8()

int MADS::Dragonsphere::ASound::command8 ( )

protected

command8: Returns non-zero if any of the 9 channels has a non-zero _activeCount (i.e. sound is currently playing). Also clears the music-only flag (byte_12393 = 0) so the check covers all 9 channels.

callFunction()

virtual void MADS::Dragonsphere::ASound::callFunction ( uint16  offset )

protectedvirtual

Calls a function at a fixed offset within the sound driver.

Parameters

offset

Offset of the function

command18()

int MADS::Dragonsphere::ASound::command18 ( )

protected

command18: Re-entrant music launcher. First calls command1 to fade current output, then branches on _musicIndex (word_12370): <= 0x12 -> calls off_11A26 table (commands 16-19) > 0x12 -> calls funcs_12251 table (commands 32-49), index = _musicIndex - 0x20

validate()

static void MADS::Dragonsphere::ASound::validate ( bool  isDemo )

static

Validate the sound driver files needed for data

stop()

virtual int MADS::Dragonsphere::ASound::stop ( )

overridevirtual

Stop all currently playing sounds (wraps command0).

Implements MADS::SoundDriver.

poll()

int MADS::Dragonsphere::ASound::poll ( )

overridevirtual

Main poll method; drives the per-frame update.

Implements MADS::SoundDriver.

noise()

void MADS::Dragonsphere::ASound::noise ( )

overridevirtual

Noise channel tick: for each of the 9 channels calls noise_inner, which randomises the voice frequency each frame using _noiseFreqMask.

Implements MADS::SoundDriver.

playSound()

void MADS::Dragonsphere::ASound::playSound

(

int

offset

)

Starts playback of the sound data at the given byte offset within the driver's data segment, using findFreeChannelFull to select a channel.

setVolume()

void MADS::Dragonsphere::ASound::setVolume ( int  volume )

inlineoverridevirtual

Set the volume

Implements MADS::SoundDriver.

Member Data Documentation

_channels

AdlibChannel* MADS::Dragonsphere::ASound::_channels[9]

protected

Initial value:

= {
        &_channel0, &_channel1, &_channel2,
        &_channel3, &_channel4, &_channel5,
        &_channel6, &_channel7, &_channel8
    }

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The documentation for this class was generated from the following file:

• engines/mads/dragonsphere/asound.h