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// Sega Master System/Mark III, Sega Genesis/Mega Drive, BBC Micro VGM music file emulator
// Game_Music_Emu 0.5.2
#ifndef VGM_EMU_H
#define VGM_EMU_H
#include "Vgm_Emu_Impl.h"
// Emulates VGM music using SN76489/SN76496 PSG, YM2612, and YM2413 FM sound chips.
// Supports custom sound buffer and frequency equalization when VGM uses just the PSG.
// FM sound chips can be run at their proper rates, or slightly higher to reduce
// aliasing on high notes. Currently YM2413 support requires that you supply a
// YM2413 sound chip emulator. I can provide one I've modified to work with the library.
class Vgm_Emu : public Vgm_Emu_Impl {
public:
// True if custom buffer and custom equalization are supported
// TODO: move into Music_Emu and rename to something like supports_custom_buffer()
bool is_classic_emu() const { return !uses_fm; }
// Disable 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; }
// VGM header format
enum { header_size = 0x40 };
struct header_t
{
char tag [4];
byte data_size [4];
byte version [4];
byte psg_rate [4];
byte ym2413_rate [4];
byte gd3_offset [4];
byte track_duration [4];
byte loop_offset [4];
byte loop_duration [4];
byte frame_rate [4];
byte noise_feedback [2];
byte noise_width;
byte unused1;
byte ym2612_rate [4];
byte ym2151_rate [4];
byte data_offset [4];
byte unused2 [8];
};
// Header for currently loaded file
header_t const& header() const { return *(header_t const*) data; }
static gme_type_t static_type() { return gme_vgm_type; }
public:
// deprecated
Music_Emu::load;
blargg_err_t load( header_t const& h, Data_Reader& in ) // use Remaining_Reader
{ return load_remaining_( &h, sizeof h, in ); }
byte const* gd3_data( int* size_out = 0 ) const; // use track_info()
public:
Vgm_Emu();
~Vgm_Emu();
protected:
blargg_err_t track_info_( track_info_t*, int track ) const;
blargg_err_t load_mem_( byte const*, long );
blargg_err_t set_sample_rate_( long sample_rate );
blargg_err_t start_track_( int );
blargg_err_t play_( long count, sample_t* );
blargg_err_t run_clocks( blip_time_t&, int );
void set_tempo_( double );
void mute_voices_( int mask );
void set_voice( int, Blip_Buffer*, Blip_Buffer*, Blip_Buffer* );
void update_eq( blip_eq_t const& );
private:
// removed; use disable_oversampling() and set_tempo() instead
Vgm_Emu( bool oversample, double tempo = 1.0 );
double fm_rate;
long psg_rate;
long vgm_rate;
bool disable_oversampling_;
bool uses_fm;
blargg_err_t setup_fm();
};
#endif
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