bsnes/higan/ms/psg/psg.cpp

71 lines
1.7 KiB
C++

#include <ms/ms.hpp>
namespace MasterSystem {
PSG psg;
#include "io.cpp"
#include "tone.cpp"
#include "noise.cpp"
#include "serialization.cpp"
auto PSG::Enter() -> void {
while(true) scheduler.synchronize(), psg.main();
}
auto PSG::main() -> void {
tone0.run();
tone1.run();
tone2.run();
noise.run();
int left = 0;
if(tone0.output && tone0.left) left += levels[tone0.volume];
if(tone1.output && tone1.left) left += levels[tone1.volume];
if(tone2.output && tone2.left) left += levels[tone2.volume];
if(noise.output && noise.left) left += levels[noise.volume];
lowpassLeft += (left - lowpassLeft) * 20 / 256;
left = left * 2 / 6 + lowpassLeft * 3 / 4;
left = sclamp<16>(left - 32768);
int right = 0;
if(tone0.output && tone0.right) right += levels[tone0.volume];
if(tone1.output && tone1.right) right += levels[tone1.volume];
if(tone2.output && tone2.right) right += levels[tone2.volume];
if(noise.output && noise.right) right += levels[noise.volume];
lowpassRight += (right - lowpassRight) * 20 / 256;
right = right * 2 / 6 + lowpassRight * 3 / 4;
right = sclamp<16>(right - 32768);
stream->sample(left / 32768.0, right / 32768.0);
step(1);
}
auto PSG::step(uint clocks) -> void {
Thread::step(clocks);
synchronize(cpu);
}
auto PSG::power() -> void {
//Master System is monaural; Game Gear is stereo
//use stereo mode for both; output same sample to both channels for Master System
create(PSG::Enter, system.colorburst() / 16.0);
stream = Emulator::audio.createStream(2, frequency());
select = 0;
lowpassLeft = 0;
lowpassRight = 0;
for(auto n : range(15)) {
levels[n] = 0x2000 * pow(2, n * -2.0 / 6.0) + 0.5;
}
levels[15] = 0;
tone0.power();
tone1.power();
tone2.power();
noise.power();
}
}