cog/Frameworks/GME/gme/Gym_Emu.h

89 lines
2.5 KiB
C++

// Sega Genesis/Mega Drive GYM music file emulator
// Performs PCM timing recovery to improve sample quality.
// Game_Music_Emu $vers
#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 {
public:
// GYM file header (optional; many files have NO header at all)
struct header_t
{
enum { size = 428 };
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; }
// Disables running FM chips at higher than normal rate. Will result in slightly
// more aliasing of high notes.
void disable_oversampling( bool disable = true ) { disable_oversampling_ = disable; }
blargg_err_t hash_( Hash_Function& ) const;
// Implementation
public:
Gym_Emu();
~Gym_Emu();
protected:
virtual blargg_err_t load_mem_( byte const [], int );
virtual blargg_err_t track_info_( track_info_t*, int track ) const;
virtual blargg_err_t set_sample_rate_( int sample_rate );
virtual blargg_err_t start_track_( int );
virtual blargg_err_t play_( int count, sample_t [] );
virtual void mute_voices_( int );
virtual void set_tempo_( double );
private:
// Log
byte const* pos; // current position
byte const* loop_begin;
int log_offset; // size of header (0 or header_t::size)
int loop_remain; // frames remaining until loop_begin has been located
int clocks_per_frame;
bool disable_oversampling_;
// PCM
int pcm_amp;
int prev_pcm_count; // for detecting beginning/end of group of samples
int pcm_enabled;
// large objects
Dual_Resampler resampler;
Stereo_Buffer stereo_buf;
Blip_Buffer * pcm_buf;
Ym2612_Emu fm;
Sms_Apu apu;
Blip_Synth_Fast pcm_synth;
header_t header_;
byte const* log_begin() const { return file_begin() + log_offset; }
void parse_frame();
void run_pcm( byte const in [], int count );
int play_frame( blip_time_t blip_time, int sample_count, sample_t buf [] );
static int play_frame_( void*, blip_time_t, int, sample_t [] );
};
#endif