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More comments, and some very minor cleanup.

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svn-id: r21208
This commit is contained in:
Torbjörn Andersson 2006-03-10 15:30:22 +00:00
parent b07e6f6eed
commit 47589ec06f
1 changed files with 46 additions and 3 deletions
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49
engines/kyra/sound_adlib.cpp
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@ -272,6 +272,39 @@ private:
int updateCallback55(uint8 *&dataptr, OutputState &state, uint8 value);
int updateCallback56(uint8 *&dataptr, OutputState &state, uint8 value);
private:
// These variables have not yet been named, but some of them are partly
// known nevertheless:
//
// _unk4 - Unknown, but probably indicates that Adlib's
// rhythm section is active.
// _unk5 - Currently unused, except for updateCallback54()
// _unkValue1 - Unknown. Used for updating _unkValue2
// _unkValue2 - Unknown. Used for updating _unkValue4
// _unkValue3 - Unknown. Used for updating _unkValue2
// _unkValue4 - Unknown. Used for updating _unkValue5
// _unkValue5 - Unknown. Used for controlling updateCallback24().
// _unkValue6 - Unknown. Something to do with channel 1 volume?
// _unkValue7 - Unknown. Something to do with channel 2 volume?
// _unkValue8 - Unknown. Something to do with channel 2 volume?
// _unkValue9 - Unknown. Something to do with channel 3 volume?
// _unkValue10 - Unknown. Something to do with channel 3 volume?
// _unkValue11 - Unknown. Something to do with channel 2 volume?
// _unkValue12 - Unknown. Something to do with channel 2 volume?
// _unkValue13 - Unknown. Something to do with channel 3 volume?
// _unkValue14 - Unknown. Something to do with channel 3 volume?
// _unkValue15 - Unknown. Something to do with channel 3 volume?
// _unkValue16 - Unknown. Something to do with channel 3 volume?
// _unkValue17 - Unknown. Something to do with channel 2 volume?
// _unkValue18 - Unknown. Something to do with channel 2 volume?
// _unkValue19 - Unknown. Something to do with channel 1 volume?
// _unkValue20 - Unknown. Something to do with channel 1 volume?
// _unkOutputByte2 - Unknown. Something to do with the BD register.
// _unkTable[] - Probably frequences for the 12-tone scale.
// _unkTable2[] - Unknown. Currently only used by updateCallback46()
// _unkTable2_1[] - One of the tables in _unkTable2[]
// _unkTable2_2[] - One of the tables in _unkTable2[]
// _unkTable2_3[] - One of the tables in _unkTable2[]
int _lastProcessed;
int8 _flagTrigger;
int _curTable;
@ -689,8 +722,13 @@ void AdlibDriver::initTable(OutputState &table) {
void AdlibDriver::noteOff(OutputState &table) {
debugC(9, kDebugLevelSound, "noteOff(%d)", &table - _outputTables);
// I believe that 9 is the percussion channel.
if (_curTable == 9)
return;
// I believe this has to do with channels 6, 7, and 8 being special
// when Adlib's rhythm section is enabled.
if (_unk4 && _curTable >= 6)
return;
@ -703,9 +741,11 @@ void AdlibDriver::noteOff(OutputState &table) {
void AdlibDriver::unkOutput2(uint8 num) {
debugC(9, kDebugLevelSound, "unkOutput2(%d)", num);
if (_unk4)
if (num >= 6)
return;
// I believe this has to do with channels 6, 7, and 8 being special
// when Adlib's rhythm section is enabled.
if (_unk4 && num >= 6)
return;
uint8 value = _outputTable[num];
@ -1913,6 +1953,9 @@ const uint16 AdlibDriver::_unkTable[] = {
0x0207, 0x0225, 0x0246
};
// These tables are currently only used by updateCallback46(), which only ever
// uses the first element of one of the sub-tables.
const uint8 *AdlibDriver::_unkTable2[] = {
AdlibDriver::_unkTable2_1,
AdlibDriver::_unkTable2_2,