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// Common interface to game music file emulators
// Game_Music_Emu 0.5.5
#ifndef MUSIC_EMU_H
#define MUSIC_EMU_H
#include "Gme_File.h"
class Multi_Buffer;
struct Music_Emu : public Gme_File {
public:
// Basic functionality (see Gme_File.h for file loading/track info functions)
// Set output sample rate. Must be called only once before loading file.
blargg_err_t set_sample_rate( long sample_rate );
// Start a track, where 0 is the first track. Also clears warning string.
blargg_err_t start_track( int );
// Generate 'count' samples info 'buf'. Output is in stereo. Any emulation
// errors set warning string, and major errors also end track.
typedef short sample_t;
blargg_err_t play( long count, sample_t* buf );
// Informational
// Sample rate sound is generated at
long sample_rate() const;
// Index of current track or -1 if one hasn't been started
int current_track() const;
// Number of voices used by currently loaded file
int voice_count() const;
// Names of voices
const char** voice_names() const;
// Track status/control
// Number of milliseconds (1000 msec = 1 second) played since beginning of track
long tell() const;
// Seek to new time in track. Seeking backwards or far forward can take a while.
blargg_err_t seek( long msec );
// Skip n samples
blargg_err_t skip( long n );
// True if a track has reached its end
bool track_ended() const;
// Set start time and length of track fade out. Once fade ends track_ended() returns
// true. Fade time can be changed while track is playing.
void set_fade( long start_msec, long length_msec = 8000 );
// Disable automatic end-of-track detection and skipping of silence at beginning
void ignore_silence( bool disable = true );
// Info for current track
Gme_File::track_info;
blargg_err_t track_info( track_info_t* out ) const;
// Sound customization
// Adjust song tempo, where 1.0 = normal, 0.5 = half speed, 2.0 = double speed.
// Track length as returned by track_info() assumes a tempo of 1.0.
void set_tempo( double );
// Mute/unmute voice i, where voice 0 is first voice
void mute_voice( int index, bool mute = true );
// Set muting state of all voices at once using a bit mask, where -1 mutes them all,
// 0 unmutes them all, 0x01 mutes just the first voice, etc.
void mute_voices( int mask );
// Change overall output amplitude, where 1.0 results in minimal clamping.
// Must be called before set_sample_rate().
void set_gain( double );
// Request use of custom multichannel buffer. Only supported by "classic" emulators;
// on others this has no effect. Should be called only once *before* set_sample_rate().
virtual void set_buffer( Multi_Buffer* ) { }
// Sound equalization (treble/bass)
// Frequency equalizer parameters (see gme.txt)
// See gme.h for definition of struct gme_equalizer_t.
typedef gme_equalizer_t equalizer_t;
// Current frequency equalizater parameters
equalizer_t const& equalizer() const;
// Set frequency equalizer parameters
void set_equalizer( equalizer_t const& );
// Equalizer settings for TV speaker
static equalizer_t const tv_eq;
public:
Music_Emu();
~Music_Emu();
protected:
void set_max_initial_silence( int n ) { max_initial_silence = n; }
void set_silence_lookahead( int n ) { silence_lookahead = n; }
void set_voice_count( int n ) { voice_count_ = n; }
void set_voice_names( const char* const* names );
void set_track_ended() { emu_track_ended_ = true; }
double gain() const { return gain_; }
double tempo() const { return tempo_; }
void remute_voices();
virtual blargg_err_t set_sample_rate_( long sample_rate ) = 0;
virtual void set_equalizer_( equalizer_t const& ) { };
virtual void mute_voices_( int mask ) = 0;
virtual void set_tempo_( double ) = 0;
virtual blargg_err_t start_track_( int ) = 0; // tempo is set before this
virtual blargg_err_t play_( long count, sample_t* out ) = 0;
virtual blargg_err_t skip_( long count );
protected:
virtual void unload();
virtual void pre_load();
virtual void post_load_();
private:
// general
equalizer_t equalizer_;
int max_initial_silence;
const char** voice_names_;
int voice_count_;
int mute_mask_;
double tempo_;
double gain_;
long sample_rate_;
blargg_long msec_to_samples( blargg_long msec ) const;
// track-specific
int current_track_;
blargg_long out_time; // number of samples played since start of track
blargg_long emu_time; // number of samples emulator has generated since start of track
bool emu_track_ended_; // emulator has reached end of track
volatile bool track_ended_;
void clear_track_vars();
void end_track_if_error( blargg_err_t );
// fading
blargg_long fade_start;
int fade_step;
void handle_fade( long count, sample_t* out );
// silence detection
int silence_lookahead; // speed to run emulator when looking ahead for silence
bool ignore_silence_;
long silence_time; // number of samples where most recent silence began
long silence_count; // number of samples of silence to play before using buf
long buf_remain; // number of samples left in silence buffer
enum { buf_size = 2048 };
blargg_vector<sample_t> buf;
void fill_buf();
void emu_play( long count, sample_t* out );
Multi_Buffer* effects_buffer;
friend Music_Emu* gme_new_emu( gme_type_t, int );
friend void gme_set_stereo_depth( Music_Emu*, double );
};
// base class for info-only derivations
struct Gme_Info_ : Music_Emu
{
virtual blargg_err_t set_sample_rate_( long sample_rate );
virtual void set_equalizer_( equalizer_t const& );
virtual void mute_voices_( int mask );
virtual void set_tempo_( double );
virtual blargg_err_t start_track_( int );
virtual blargg_err_t play_( long count, sample_t* out );
virtual void pre_load();
virtual void post_load_();
};
inline blargg_err_t Music_Emu::track_info( track_info_t* out ) const
{
return track_info( out, current_track_ );
}
inline long Music_Emu::sample_rate() const { return sample_rate_; }
inline const char** Music_Emu::voice_names() const { return voice_names_; }
inline int Music_Emu::voice_count() const { return voice_count_; }
inline int Music_Emu::current_track() const { return current_track_; }
inline bool Music_Emu::track_ended() const { return track_ended_; }
inline const Music_Emu::equalizer_t& Music_Emu::equalizer() const { return equalizer_; }
inline void Music_Emu::set_tempo_( double t ) { tempo_ = t; }
inline void Music_Emu::remute_voices() { mute_voices( mute_mask_ ); }
inline void Music_Emu::ignore_silence( bool b ) { ignore_silence_ = b; }
inline blargg_err_t Music_Emu::start_track_( int ) { return 0; }
inline void Music_Emu::set_voice_names( const char* const* names )
{
// Intentional removal of const, so users don't have to remember obscure const in middle
voice_names_ = const_cast<const char**> (names);
}
inline void Music_Emu::mute_voices_( int ) { }
inline void Music_Emu::set_gain( double g )
{
assert( !sample_rate() ); // you must set gain before setting sample rate
gain_ = g;
}
#endif
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