scummvm/engines/darkseed/adlib_worx.h

65 lines
2.3 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef DARKSEED_ADLIB_WORX_H
#define DARKSEED_ADLIB_WORX_H
#include "audio/adlib_ms.h"
namespace Darkseed {
/**
* Implementation of the AdLib code from the Worx Toolkit library,
* based on version 2.1, as used by Dark Seed (CD version).
* Implements the OPL channel allocation algorithm and note frequency
* and volume calculation.
*
* TODO Implementation is incomplete, because Dark Seed does not use
* some functionality of the library:
* - OPL rhythm mode
* - Transpose controllers 0x68 and 0x69 (seems to be buggy)
*/
class MidiDriver_Worx_AdLib : public MidiDriver_ADLIB_Multisource {
private:
/**
* The OPL instrument bank of the Worx Toolkit.
* This was taken from the Dark Seed executable and might have been
* customized for the game.
*/
static const AdLibIbkInstrumentDefinition WORX_INSTRUMENT_BANK[];
/**
* The OPL frequency (F-num) for each octave note.
*/
static const uint16 OPL_NOTE_FREQUENCIES[];
public:
MidiDriver_Worx_AdLib(OPL::Config::OplType oplType, int timerFrequency = OPL::OPL::kDefaultCallbackFrequency);
~MidiDriver_Worx_AdLib();
protected:
uint8 allocateOplChannel(uint8 channel, uint8 source, InstrumentInfo &instrumentInfo) override;
uint16 calculateFrequency(uint8 channel, uint8 source, uint8 note) override;
uint8 calculateUnscaledVolume(uint8 channel, uint8 source, uint8 velocity, const OplInstrumentDefinition &instrumentDef, uint8 operatorNum) override;
};
} // namespace Darkseed
#endif // DARKSEED_ADLIB_WORX_H