gzdoom/game-music-emu/gme/Hes_Apu.h
2018-11-01 00:15:41 +01:00

66 lines
1.4 KiB
C++

// Turbo Grafx 16 (PC Engine) PSG sound chip emulator
// Game_Music_Emu https://bitbucket.org/mpyne/game-music-emu/
#ifndef HES_APU_H
#define HES_APU_H
#include "blargg_common.h"
#include "Blip_Buffer.h"
struct Hes_Osc
{
unsigned char wave [32];
short volume [2];
int last_amp [2];
int delay;
int period;
unsigned char noise;
unsigned char phase;
unsigned char balance;
unsigned char dac;
blip_time_t last_time;
Blip_Buffer* outputs [2];
Blip_Buffer* chans [3];
unsigned noise_lfsr;
unsigned char control;
enum { amp_range = 0x8000 };
typedef Blip_Synth<blip_med_quality,1> synth_t;
void run_until( synth_t& synth, blip_time_t );
};
class Hes_Apu {
public:
void treble_eq( blip_eq_t const& );
void volume( double );
enum { osc_count = 6 };
void osc_output( int index, Blip_Buffer* center, Blip_Buffer* left, Blip_Buffer* right );
void reset();
enum { start_addr = 0x0800 };
enum { end_addr = 0x0809 };
void write_data( blip_time_t, int addr, int data );
void end_frame( blip_time_t );
public:
Hes_Apu();
private:
Hes_Osc oscs [osc_count];
int latch;
int balance;
Hes_Osc::synth_t synth;
void balance_changed( Hes_Osc& );
void recalc_chans();
};
inline void Hes_Apu::volume( double v ) { synth.volume( 1.8 / osc_count / Hes_Osc::amp_range * v ); }
inline void Hes_Apu::treble_eq( blip_eq_t const& eq ) { synth.treble_eq( eq ); }
#endif