sound_sarien.h

/* 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 AGI_SOUND_SARIEN_H
#define AGI_SOUND_SARIEN_H

#include "audio/audiostream.h"

namespace Agi {

#define BUFFER_SIZE 410

#define WAVEFORM_SIZE 64
#define ENV_ATTACK    10000 
#define ENV_DECAY     1000  
#define ENV_SUSTAIN   100   
#define ENV_RELEASE   7500  
#define NUM_CHANNELS  7     
enum AgiSoundFlags {
    AGI_SOUND_LOOP      = 0x0001,
    AGI_SOUND_ENVELOPE  = 0x0002
};
enum AgiSoundEnv {
    AGI_SOUND_ENV_ATTACK    = 3,
    AGI_SOUND_ENV_DECAY     = 2,
    AGI_SOUND_ENV_SUSTAIN   = 1,
    AGI_SOUND_ENV_RELEASE   = 0
};


struct ChannelInfo {
    AgiSoundEmuType type;
    const uint8 *ptr; // Pointer to the AgiNote data
    const int16 *ins;
    int32 size;
    uint32 phase;
    uint32 flags;   // ORs values from AgiSoundFlags
    AgiSoundEnv adsr;
    int32 timer;
    uint32 end;
    uint32 freq;
    uint32 vol;
    uint32 env;
};

class SoundGenSarien : public SoundGen, public Audio::AudioStream {
public:
    SoundGenSarien(AgiBase *vm, Audio::Mixer *pMixer);
    ~SoundGenSarien() override;

    void play(int resnum) override;
    void stop() override;

    // AudioStream API
    int readBuffer(int16 *buffer, const int numSamples) override;

    bool isStereo() const override {
        return false;
    }

    bool endOfData() const override {
        return false;
    }

    int getRate() const override {
        // FIXME: Ideally, we should use _sampleRate.
        return 22050;
    }

private:
    ChannelInfo _chn[NUM_CHANNELS];
    uint8 _env;

    int16 *_sndBuffer;
    const int16 *_waveform;

    bool _useChorus;

    bool _playing;
    int _playingSound;

private:
    void playSound();
    uint32 mixSound();
    void fillAudio(int16 *stream, uint len);

    void stopNote(int i);
    void playNote(int i, int freq, int vol);

};

} // End of namespace Agi

#endif /* AGI_SOUND_SARIEN_H */