Gym_Emu.h

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// Sega Genesis/Mega Drive GYM music file emulator
// Includes with PCM timing recovery to improve sample quality.
 
// Game_Music_Emu https://bitbucket.org/mpyne/game-music-emu/
#ifndef GYM_EMU_H
#define GYM_EMU_H
 
#include "Dual_Resampler.h"
#include "Ym2612_Emu.h"
#include "Music_Emu.h"
#include "Sms_Apu.h"
 
class Gym_Emu : public Music_Emu, private Dual_Resampler {
public:
        // GYM file header
        enum { header_size = 428 };
        struct header_t
        {
            char tag [4];
            char song [32];
            char game [32];
            char copyright [32];
            char emulator [32];
            char dumper [32];
            char comment [256];
            byte loop_start [4]; // in 1/60 seconds, 0 if not looped
            byte packed [4];
        };
        
        // Header for currently loaded file
        header_t const& header() const { return header_; }
        
        static gme_type_t static_type() { return gme_gym_type; }
        
public:
        // deprecated
        using Music_Emu::load;
        blargg_err_t load( header_t const& h, Data_Reader& in ) // use Remaining_Reader
                        { return load_remaining_( &h, sizeof h, in ); }
        enum { gym_rate = 60 }; 
        long track_length() const; // use track_info()
 
public:
        Gym_Emu();
        ~Gym_Emu();
protected:
        blargg_err_t load_mem_( byte const*, long );
        blargg_err_t track_info_( track_info_t*, int track ) const;
        blargg_err_t set_sample_rate_( long sample_rate );
        blargg_err_t start_track_( int );
        blargg_err_t play_( long count, sample_t* );
        void mute_voices_( int );
        void set_tempo_( double );
        int play_frame( blip_time_t blip_time, int sample_count, sample_t* buf );
private:
        // sequence data begin, loop begin, current position, end
        const byte* data;
        const byte* loop_begin;
        const byte* pos;
        const byte* data_end;
        blargg_long loop_remain; // frames remaining until loop beginning has been located
        header_t header_;
        double fm_sample_rate;
        blargg_long clocks_per_frame;
        void parse_frame();
        
        // dac (pcm)
        int dac_amp;
        int prev_dac_count;
        bool dac_enabled;
        bool dac_muted;
        void run_dac( int );
        
        // sound
        Blip_Buffer blip_buf;
        Ym2612_Emu fm;
        Blip_Synth<blip_med_quality,1> dac_synth;
        Sms_Apu apu;
        byte dac_buf [1024];
};
 
#endif