mirror of
https://github.com/ZDoom/gzdoom.git
synced 2024-11-27 06:12:19 +00:00
95 lines
2 KiB
C++
95 lines
2 KiB
C++
// Konami VRC6 sound chip emulator
|
|
|
|
// Nes_Snd_Emu 0.1.8
|
|
#ifndef NES_VRC6_APU_H
|
|
#define NES_VRC6_APU_H
|
|
|
|
#include "blargg_common.h"
|
|
#include "Blip_Buffer.h"
|
|
|
|
struct vrc6_apu_state_t;
|
|
|
|
class Nes_Vrc6_Apu {
|
|
public:
|
|
// See Nes_Apu.h for reference
|
|
void reset();
|
|
void volume( double );
|
|
void treble_eq( blip_eq_t const& );
|
|
void output( Blip_Buffer* );
|
|
enum { osc_count = 3 };
|
|
void osc_output( int index, Blip_Buffer* );
|
|
void end_frame( blip_time_t );
|
|
void save_state( vrc6_apu_state_t* ) const;
|
|
void load_state( vrc6_apu_state_t const& );
|
|
|
|
// Oscillator 0 write-only registers are at $9000-$9002
|
|
// Oscillator 1 write-only registers are at $A000-$A002
|
|
// Oscillator 2 write-only registers are at $B000-$B002
|
|
enum { reg_count = 3 };
|
|
enum { base_addr = 0x9000 };
|
|
enum { addr_step = 0x1000 };
|
|
void write_osc( blip_time_t, int osc, int reg, int data );
|
|
|
|
public:
|
|
Nes_Vrc6_Apu();
|
|
BLARGG_DISABLE_NOTHROW
|
|
private:
|
|
// noncopyable
|
|
Nes_Vrc6_Apu( const Nes_Vrc6_Apu& );
|
|
Nes_Vrc6_Apu& operator = ( const Nes_Vrc6_Apu& );
|
|
|
|
struct Vrc6_Osc
|
|
{
|
|
uint8_t regs [3];
|
|
Blip_Buffer* output;
|
|
int delay;
|
|
int last_amp;
|
|
int phase;
|
|
int amp; // only used by saw
|
|
|
|
int period() const
|
|
{
|
|
return (regs [2] & 0x0F) * 0x100L + regs [1] + 1;
|
|
}
|
|
};
|
|
|
|
Vrc6_Osc oscs [osc_count];
|
|
blip_time_t last_time;
|
|
|
|
Blip_Synth<blip_med_quality,1> saw_synth;
|
|
Blip_Synth<blip_good_quality,1> square_synth;
|
|
|
|
void run_until( blip_time_t );
|
|
void run_square( Vrc6_Osc& osc, blip_time_t );
|
|
void run_saw( blip_time_t );
|
|
};
|
|
|
|
struct vrc6_apu_state_t
|
|
{
|
|
uint8_t regs [3] [3];
|
|
uint8_t saw_amp;
|
|
uint16_t delays [3];
|
|
uint8_t phases [3];
|
|
uint8_t unused;
|
|
};
|
|
|
|
inline void Nes_Vrc6_Apu::osc_output( int i, Blip_Buffer* buf )
|
|
{
|
|
assert( (unsigned) i < osc_count );
|
|
oscs [i].output = buf;
|
|
}
|
|
|
|
inline void Nes_Vrc6_Apu::volume( double v )
|
|
{
|
|
double const factor = 0.0967 * 2;
|
|
saw_synth.volume( factor / 31 * v );
|
|
square_synth.volume( factor * 0.5 / 15 * v );
|
|
}
|
|
|
|
inline void Nes_Vrc6_Apu::treble_eq( blip_eq_t const& eq )
|
|
{
|
|
saw_synth.treble_eq( eq );
|
|
square_synth.treble_eq( eq );
|
|
}
|
|
|
|
#endif
|