cog/Frameworks/GME/gme/Ym2612_Emu_MAME.cpp

98 lines
2.0 KiB
C++

// Game_Music_Emu $vers. http://www.slack.net/~ant/
#ifdef YM2612_EMU_CPP
#include "Ym2612_Emu.h"
extern "C" {
#include "../vgmplay/chips/mamedef.h"
#include "../vgmplay/chips/fm.h"
}
#include "blargg_errors.h"
// Ym2612_Emu
Ym2612_Emu::~Ym2612_Emu()
{
if ( impl )
ym2612_shutdown( impl );
}
static BOOST::uint8_t dummy = 0;
const char* Ym2612_Emu::set_rate( double sample_rate, double clock_rate )
{
if ( impl )
{
ym2612_shutdown( impl );
impl = 0;
}
if ( !clock_rate )
clock_rate = sample_rate * 144.;
impl = ym2612_init( 0, (int) (clock_rate + 0.5), (int) (sample_rate + 0.5), 0, 0, &dummy, 0 );
if ( !impl )
return blargg_err_memory;
return 0;
}
void Ym2612_Emu::reset()
{
ym2612_reset_chip( impl );
}
static stream_sample_t* DUMMYBUF[0x02] = {(stream_sample_t*)NULL, (stream_sample_t*)NULL};
void Ym2612_Emu::write0( int addr, int data )
{
ym2612_update_one( impl, DUMMYBUF, 0 );
ym2612_write( impl, 0, addr );
ym2612_write( impl, 1, data );
}
void Ym2612_Emu::write1( int addr, int data )
{
ym2612_update_one( impl, DUMMYBUF, 0 );
ym2612_write( impl, 2, addr );
ym2612_write( impl, 3, data );
}
void Ym2612_Emu::mute_voices( int mask )
{
ym2612_set_mutemask( impl, mask );
}
void Ym2612_Emu::run( int pair_count, sample_t* out )
{
stream_sample_t bufL[ 1024 ];
stream_sample_t bufR[ 1024 ];
stream_sample_t * buffers[2] = { bufL, bufR };
while (pair_count > 0)
{
int todo = pair_count;
if (todo > 1024) todo = 1024;
ym2612_update_one( impl, buffers, todo );
for (int i = 0; i < todo; i++)
{
int output_l = bufL [i];
int output_r = bufR [i];
output_l += out [0];
output_r += out [1];
if ( (short)output_l != output_l ) output_l = 0x7FFF ^ ( output_l >> 31 );
if ( (short)output_r != output_r ) output_r = 0x7FFF ^ ( output_r >> 31 );
out [0] = output_l;
out [1] = output_r;
out += 2;
}
pair_count -= todo;
}
}
#endif