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use crate::{SoundChip, Stereo, Vtx};
use aym::{AySample, AymBackend};
use num_traits::Num;
pub type PrecisePlayer = Player<aym::AymPrecise>;
pub struct Player<AY: AymBackend> {
vtx: Vtx,
frame: usize,
frame_sample: usize,
stereo: bool,
ay: AY,
samples_per_frame: usize,
}
pub trait PlayerSample: Num {
fn from_aym_sample(sample: impl aym::AySample) -> Self;
}
impl PlayerSample for i8 {
fn from_aym_sample(sample: impl AySample) -> Self {
sample.to_i8()
}
}
impl PlayerSample for i16 {
fn from_aym_sample(sample: impl AySample) -> Self {
sample.to_i16()
}
}
impl PlayerSample for i32 {
fn from_aym_sample(sample: impl AySample) -> Self {
sample.to_i32()
}
}
impl PlayerSample for f32 {
fn from_aym_sample(sample: impl AySample) -> Self {
sample.to_f32()
}
}
impl PlayerSample for f64 {
fn from_aym_sample(sample: impl AySample) -> Self {
sample.to_f64()
}
}
impl<AY: AymBackend> Player<AY> {
pub fn new(vtx: Vtx, sample_rate: usize, stereo: bool) -> Self {
let chip_type = match vtx.chip {
SoundChip::AY => aym::SoundChip::AY,
SoundChip::YM => aym::SoundChip::YM,
};
let mode = if stereo {
match vtx.stereo {
Stereo::Mono => aym::AyMode::Mono,
Stereo::ABC => aym::AyMode::ABC,
Stereo::ACB => aym::AyMode::ACB,
Stereo::BAC => aym::AyMode::BAC,
Stereo::BCA => aym::AyMode::BCA,
Stereo::CAB => aym::AyMode::CAB,
Stereo::CBA => aym::AyMode::CBA,
}
} else {
aym::AyMode::Mono
};
let ay = AY::new(chip_type, mode, vtx.frequency as usize, sample_rate);
let samples_per_frame = sample_rate / vtx.player_frequency as usize;
Self {
vtx,
frame: 0,
frame_sample: 0,
stereo,
ay,
samples_per_frame,
}
}
fn update_ay(&mut self) -> bool {
if let Some(frame) = self.vtx.frame_registers(self.frame) {
for (idx, value) in frame.iter().copied().enumerate() {
if idx == 13 && value == 0xFF {
continue;
}
self.ay.write_register(idx as u8, value);
}
return true;
}
false
}
pub fn play<S: PlayerSample>(&mut self, samples: &mut [S]) -> usize {
let mut processed_samples = 0;
if self.stereo {
for sample in samples.chunks_exact_mut(2) {
if self.frame_sample == 0 && !self.update_ay() {
return processed_samples * 2;
}
let ay_sample = self.ay.next_sample();
sample[0] = S::from_aym_sample(ay_sample.left);
sample[1] = S::from_aym_sample(ay_sample.right);
processed_samples += 1;
self.frame_sample += 1;
if self.frame_sample == self.samples_per_frame {
self.frame_sample = 0;
self.frame += 1;
}
}
processed_samples * 2
} else {
for sample in samples {
if self.frame_sample == 0 && !self.update_ay() {
return processed_samples;
}
let ay_sample = self.ay.next_sample();
*sample = S::from_aym_sample(ay_sample.left);
processed_samples += 1;
self.frame_sample += 1;
if self.frame_sample == self.samples_per_frame {
self.frame_sample = 0;
self.frame += 1;
}
}
processed_samples
}
}
pub fn rewind(&mut self) {
self.frame = 0;
self.frame_sample = 0;
self.ay.write_register(13, 0);
}
pub fn rewind_loop(&mut self) {
self.frame = self.vtx.loop_start_frame as usize;
self.frame_sample = 0;
self.ay.write_register(13, 0);
}
pub fn set_frame(&mut self, frame: usize) -> bool {
if frame >= self.vtx.frames_count() {
return false;
}
self.frame = frame;
self.frame_sample = 0;
self.ay.write_register(13, 0);
true
}
}
#[cfg(test)]
mod tests {
use super::*;
use expect_test::expect;
use sha2::{Digest, Sha256};
fn generate_samples_hash_for_vtx<B: AymBackend>(data: &[u8]) -> String {
const SAMPLE_RATE: usize = 44100;
let vtx = Vtx::load(std::io::Cursor::new(data)).unwrap();
let buffer_size = SAMPLE_RATE * 15;
let mut buffer = vec![0i16; buffer_size];
let mut player = PrecisePlayer::new(vtx, SAMPLE_RATE, true);
let actual_length = player.play(&mut buffer);
buffer.truncate(actual_length);
let mut hashable_buffer = Vec::with_capacity(buffer.len() * 2);
buffer.into_iter().for_each(|sample| {
hashable_buffer.extend_from_slice(&sample.to_ne_bytes());
});
let mut hasher = Sha256::default();
hasher.update(&hashable_buffer);
let frame_data_fingerprint = hasher.finalize();
format!("{:x}", frame_data_fingerprint)
}
#[test]
fn precise_player_wroks_normally() {
expect![[r#"65127ad0e493b23b43e838b6281d7f8d07a47549efd0c9d1eda3d3ccaf0b7e5c"#]].assert_eq(
&generate_samples_hash_for_vtx::<aym::AymPrecise>(include_bytes!("test/csoon.vtx")),
)
}
}