zmusic/thirdparty/game-music-emu/gme/Gym_Emu.h
Christoph Oelckers a4eae42ec5 - initial commit
2020-01-02 17:52:30 +01:00

82 lines
2 KiB
C++

// 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