scummvm/sound/fmopl.h
Johannes Schickel 72686a5a9e Make 'create' return an OPL2 by default.
svn-id: r40503
2009-05-12 19:24:04 +00:00

179 lines
4.4 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.
*
* $URL$
* $Id$
*/
#ifndef SOUND_FMOPL_H
#define SOUND_FMOPL_H
#include "common/scummsys.h"
#include "common/str.h"
namespace OPL {
class OPL;
class Config {
public:
enum OplFlags {
kFlagOpl2 = (1 << 0),
kFlagDualOpl2 = (1 << 1),
kFlagOpl3 = (1 << 2)
};
/**
* OPL type to emulate.
*/
enum OplType {
kOpl2,
kDualOpl2,
kOpl3
};
typedef int8 DriverId;
struct EmulatorDescription {
const char *name;
const char *description;
DriverId id; // A unique ID for each driver
uint32 flags; // Capabilities of this driver
};
/**
* Get a list of all available OPL emulators.
* @return list of all available OPL emulators, terminated by a zero entry
*/
static const EmulatorDescription *getAvailable() { return _drivers; }
/**
* Returns the driver id of a given name.
*/
static DriverId parse(const Common::String &name);
/**
* Detects a driver for the specific type.
*/
static DriverId detect(OplType type);
/**
* Creates the specific driver with a specific type setup.
*/
static OPL *create(DriverId driver, OplType type);
/**
* Wrapper to easily init an OPL chip, without specifing an emulator.
* By default it will try to initialize an OPL2 emulator, thus an AdLib card.
*/
static OPL *create(OplType type = kOpl2) { return create(detect(type), type); }
private:
static const EmulatorDescription _drivers[];
};
class OPL {
private:
// TODO: This is part of a temporary HACK to allow only 1 instance
static bool _hasInstance;
public:
OPL() { _hasInstance = true; }
virtual ~OPL() { _hasInstance = false; }
/**
* Initializes the OPL emulator.
*
* @param rate output sample rate
* @return true on success, false on failure
*/
virtual bool init(int rate) = 0;
/**
* Reinitializes the OPL emulator
*/
virtual void reset() = 0;
/**
* Writes a byte to the given I/O port.
*
* @param a port address
* @param v value, which will be written
*/
virtual void write(int a, int v) = 0;
/**
* Reads a byte from the given I/O port.
*
* @param a port address
* @return value read
*/
virtual byte read(int a) = 0;
/**
* Function to directly write to a specific OPL register.
* This writes to *both* chips for a Dual OPL2.
*
* @param r hardware register number to write to
* @param v value, which will be written
*/
virtual void writeReg(int r, int v) = 0;
/**
* Read up to 'length' samples.
*
* Data will be in native endianess, 16 bit per sample, signed.
* For stereo OPL, buffer will be filled with interleaved
* left and right channel samples, starting with a left sample.
* Furthermore, the samples in the left and right are summed up.
* So if you request 4 samples from a stereo OPL, you will get
* a total of two left channel and two right channel samples.
*/
virtual void readBuffer(int16 *buffer, int length) = 0;
/**
* Returns whether the setup OPL mode is stereo or not
*/
virtual bool isStereo() const = 0;
};
} // end of namespace OPL
// Legacy API
// !You should not write any new code using the legacy API!
typedef OPL::OPL FM_OPL;
void OPLDestroy(FM_OPL *OPL);
void OPLResetChip(FM_OPL *OPL);
void OPLWrite(FM_OPL *OPL, int a, int v);
unsigned char OPLRead(FM_OPL *OPL, int a);
void OPLWriteReg(FM_OPL *OPL, int r, int v);
void YM3812UpdateOne(FM_OPL *OPL, int16 *buffer, int length);
/**
* Legacy factory to create an AdLib (OPL2) chip.
*
* !You should not write any new code using the legacy API!
*/
FM_OPL *makeAdlibOPL(int rate);
#endif