mirror of
https://github.com/libretro/scummvm.git
synced 2024-12-23 10:19:27 +00:00
149 lines
4.5 KiB
C++
149 lines
4.5 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.
|
|
*
|
|
*/
|
|
|
|
#ifndef SOUND_MIXER_INTERN_H
|
|
#define SOUND_MIXER_INTERN_H
|
|
|
|
#include "common/scummsys.h"
|
|
#include "common/mutex.h"
|
|
#include "audio/mixer.h"
|
|
|
|
namespace Audio {
|
|
|
|
/**
|
|
* The (default) implementation of the ScummVM audio mixing subsystem.
|
|
*
|
|
* Backends are responsible for allocating (and later releasing) an instance
|
|
* of this class, which engines can access via OSystem::getMixer().
|
|
*
|
|
* Initialisation of instances of this class usually happens as follows:
|
|
* 1) Creat a new Audio::MixerImpl instance.
|
|
* 2) Set the hardware output sample rate via the setSampleRate() method.
|
|
* 3) Hook up the mixCallback() in a suitable audio processing thread/callback.
|
|
* 4) Change the mixer into ready mode via setReady(true).
|
|
* 5) Start audio processing (e.g. by resuming the audio thread, if applicable).
|
|
*
|
|
* In the future, we might make it possible for backends to provide
|
|
* (partial) alternative implementations of the mixer, e.g. to make
|
|
* better use of native sound mixing support on low-end devices.
|
|
*
|
|
* @see OSystem::getMixer()
|
|
*/
|
|
class MixerImpl : public Mixer {
|
|
private:
|
|
enum {
|
|
NUM_CHANNELS = 16
|
|
};
|
|
|
|
OSystem *_syst;
|
|
Common::Mutex _mutex;
|
|
|
|
const uint _sampleRate;
|
|
bool _mixerReady;
|
|
uint32 _handleSeed;
|
|
|
|
struct SoundTypeSettings {
|
|
SoundTypeSettings() : mute(false), volume(kMaxMixerVolume) {}
|
|
|
|
bool mute;
|
|
int volume;
|
|
};
|
|
|
|
SoundTypeSettings _soundTypeSettings[4];
|
|
Channel *_channels[NUM_CHANNELS];
|
|
|
|
|
|
public:
|
|
|
|
MixerImpl(OSystem *system, uint sampleRate);
|
|
~MixerImpl();
|
|
|
|
virtual bool isReady() const { return _mixerReady; }
|
|
|
|
virtual void playStream(
|
|
SoundType type,
|
|
SoundHandle *handle,
|
|
AudioStream *input,
|
|
int id, byte volume, int8 balance,
|
|
DisposeAfterUse::Flag autofreeStream,
|
|
bool permanent,
|
|
bool reverseStereo);
|
|
|
|
virtual void stopAll();
|
|
virtual void stopID(int id);
|
|
virtual void stopHandle(SoundHandle handle);
|
|
|
|
virtual void pauseAll(bool paused);
|
|
virtual void pauseID(int id, bool paused);
|
|
virtual void pauseHandle(SoundHandle handle, bool paused);
|
|
|
|
virtual bool isSoundIDActive(int id);
|
|
virtual int getSoundID(SoundHandle handle);
|
|
|
|
virtual bool isSoundHandleActive(SoundHandle handle);
|
|
|
|
virtual void muteSoundType(SoundType type, bool mute);
|
|
virtual bool isSoundTypeMuted(SoundType type) const;
|
|
|
|
virtual void setChannelVolume(SoundHandle handle, byte volume);
|
|
virtual byte getChannelVolume(SoundHandle handle);
|
|
virtual void setChannelBalance(SoundHandle handle, int8 balance);
|
|
virtual int8 getChannelBalance(SoundHandle handle);
|
|
|
|
virtual uint32 getSoundElapsedTime(SoundHandle handle);
|
|
virtual Timestamp getElapsedTime(SoundHandle handle);
|
|
|
|
virtual bool hasActiveChannelOfType(SoundType type);
|
|
|
|
virtual void setVolumeForSoundType(SoundType type, int volume);
|
|
virtual int getVolumeForSoundType(SoundType type) const;
|
|
|
|
virtual uint getOutputRate() const;
|
|
|
|
protected:
|
|
void insertChannel(SoundHandle *handle, Channel *chan);
|
|
|
|
public:
|
|
/**
|
|
* The mixer callback function, to be called at regular intervals by
|
|
* the backend (e.g. from an audio mixing thread). All the actual mixing
|
|
* work is done from here.
|
|
*
|
|
* @param samples Sample buffer, in which stereo 16-bit samples will be stored.
|
|
* @param len Length of the provided buffer to fill (in bytes, should be divisible by 4).
|
|
* @return number of sample pairs processed (which can still be silence!)
|
|
*/
|
|
int mixCallback(byte *samples, uint len);
|
|
|
|
/**
|
|
* Set the internal 'is ready' flag of the mixer.
|
|
* Backends should invoke Mixer::setReady(true) once initialisation of
|
|
* their audio system has been completed.
|
|
*/
|
|
void setReady(bool ready);
|
|
};
|
|
|
|
|
|
} // End of namespace Audio
|
|
|
|
#endif
|