mirror of
https://git.do.srb2.org/STJr/SRB2.git
synced 2024-11-28 23:21:58 +00:00
106 lines
2.3 KiB
C++
106 lines
2.3 KiB
C++
// Konami SCC sound chip emulator
|
|
|
|
// Game_Music_Emu 0.6.0
|
|
#ifndef KSS_SCC_APU_H
|
|
#define KSS_SCC_APU_H
|
|
|
|
#include "blargg_common.h"
|
|
#include "Blip_Buffer.h"
|
|
#include <string.h>
|
|
|
|
class Scc_Apu {
|
|
public:
|
|
// Set buffer to generate all sound into, or disable sound if NULL
|
|
void output( Blip_Buffer* );
|
|
|
|
// Reset sound chip
|
|
void reset();
|
|
|
|
// Write to register at specified time
|
|
enum { reg_count = 0x90 };
|
|
void write( blip_time_t time, int reg, int data );
|
|
|
|
// Run sound to specified time, end current time frame, then start a new
|
|
// time frame at time 0. Time frames have no effect on emulation and each
|
|
// can be whatever length is convenient.
|
|
void end_frame( blip_time_t length );
|
|
|
|
// Additional features
|
|
|
|
// Set sound output of specific oscillator to buffer, where index is
|
|
// 0 to 4. If buffer is NULL, the specified oscillator is muted.
|
|
enum { osc_count = 5 };
|
|
void osc_output( int index, Blip_Buffer* );
|
|
|
|
// Set overall volume (default is 1.0)
|
|
void volume( double );
|
|
|
|
// Set treble equalization (see documentation)
|
|
void treble_eq( blip_eq_t const& );
|
|
|
|
public:
|
|
Scc_Apu();
|
|
private:
|
|
enum { amp_range = 0x8000 };
|
|
struct osc_t
|
|
{
|
|
int delay;
|
|
int phase;
|
|
int last_amp;
|
|
Blip_Buffer* output;
|
|
};
|
|
osc_t oscs [osc_count];
|
|
blip_time_t last_time;
|
|
unsigned char regs [reg_count];
|
|
Blip_Synth<blip_med_quality,1> synth;
|
|
|
|
void run_until( blip_time_t );
|
|
};
|
|
|
|
inline void Scc_Apu::volume( double v ) { synth.volume( 0.43 / osc_count / amp_range * v ); }
|
|
|
|
inline void Scc_Apu::treble_eq( blip_eq_t const& eq ) { synth.treble_eq( eq ); }
|
|
|
|
inline void Scc_Apu::osc_output( int index, Blip_Buffer* b )
|
|
{
|
|
assert( (unsigned) index < osc_count );
|
|
oscs [index].output = b;
|
|
}
|
|
|
|
inline void Scc_Apu::write( blip_time_t time, int addr, int data )
|
|
{
|
|
assert( (unsigned) addr < reg_count );
|
|
run_until( time );
|
|
regs [addr] = data;
|
|
}
|
|
|
|
inline void Scc_Apu::end_frame( blip_time_t end_time )
|
|
{
|
|
if ( end_time > last_time )
|
|
run_until( end_time );
|
|
last_time -= end_time;
|
|
assert( last_time >= 0 );
|
|
}
|
|
|
|
inline void Scc_Apu::output( Blip_Buffer* buf )
|
|
{
|
|
for ( int i = 0; i < osc_count; i++ )
|
|
oscs [i].output = buf;
|
|
}
|
|
|
|
inline Scc_Apu::Scc_Apu()
|
|
{
|
|
output( 0 );
|
|
}
|
|
|
|
inline void Scc_Apu::reset()
|
|
{
|
|
last_time = 0;
|
|
|
|
for ( int i = 0; i < osc_count; i++ )
|
|
memset( &oscs [i], 0, offsetof (osc_t,output) );
|
|
|
|
memset( regs, 0, sizeof regs );
|
|
}
|
|
|
|
#endif
|