aym/
lib.rs

1#![no_std]
2mod backends;
3
4pub use backends::AymPrecise;
5
6use core::fmt::Debug;
7use num_traits::Num;
8
9/// AY/YM Sound chip register count
10pub const AY_REGISTER_COUNT: usize = 14;
11
12/// Samples, returned by `aym` implement this trait; It allows to correctly convert
13/// the sound sample between different types. e.g.
14/// [to_f32](AySample::to_f32)/[to_f64](AySample::to_f64) will always return sample in the
15/// correct range `[-1.0; 1.0]`, while for example [to_i8](AySample::to_i8)
16/// will return the sound sample in range `[-128; 127]`
17pub trait AySample: Num + Copy {
18    // Returns sound sample in range `[i8::MIN; i8::MAX]`
19    fn to_i8(self) -> i8;
20    // Returns sound sample in range `[i16::MIN; i16::MAX]`
21    fn to_i16(self) -> i16;
22    // Returns sound sample in range `[i32::MIN; i32::MAX]`
23    fn to_i32(self) -> i32;
24    // Returns sound sample in range `[-1.0; 1.0]`
25    fn to_f32(self) -> f32;
26    // Returns sound sample in range `[-1.0; 1.0]`
27    fn to_f64(self) -> f64;
28}
29
30impl AySample for f64 {
31    fn to_i8(self) -> i8 {
32        (i8::MAX as f64 * self).clamp(i8::MIN as f64, i8::MAX as f64) as i8
33    }
34
35    fn to_i16(self) -> i16 {
36        (i16::MAX as f64 * self).clamp(i16::MIN as f64, i16::MAX as f64) as i16
37    }
38
39    fn to_i32(self) -> i32 {
40        (i32::MAX as f64 * self).clamp(i32::MIN as f64, i32::MAX as f64) as i32
41    }
42
43    fn to_f32(self) -> f32 {
44        self as f32
45    }
46
47    fn to_f64(self) -> f64 {
48        self
49    }
50}
51
52/// Represents AY stereo sample with `left` and `right` channel samples
53#[derive(Debug)]
54pub struct StereoSample<S>
55where
56    S: AySample + Debug,
57{
58    pub left: S,
59    pub right: S,
60}
61
62/// Sound chip type
63#[derive(Debug)]
64pub enum SoundChip {
65    /// AY-3-8910 sound chip
66    AY,
67    /// YM2149 sound chip
68    YM,
69}
70
71/// Stereo configuration
72///
73/// `Both` - Played on both channels
74/// `Left` - Played only on left channel
75/// `Right` - Played only on right channel
76///
77/// | Mode | A     | B     | C     |
78/// | ---- | ----- | ----- | ----- |
79/// | Mono | Both  | Both  | Both  |
80/// | ABC  | Left  | Both  | Right |
81/// | ACB  | Left  | Right | Both  |
82/// | BAC  | Both  | Left  | Right |
83/// | BCA  | Right | Left  | Both  |
84/// | CAB  | Both  | Right | Left  |
85/// | CBA  | Right | Both  | Left  |
86#[derive(Debug)]
87#[allow(clippy::upper_case_acronyms)]
88pub enum AyMode {
89    Mono,
90    ABC,
91    ACB,
92    BAC,
93    BCA,
94    CAB,
95    CBA,
96}
97
98/// Sound library generation backend.
99///
100/// Currently is only one backend - [AymPrecise],
101pub trait AymBackend: Sized {
102    /// Resulting sample type
103    type SoundSample: AySample + Debug;
104
105    /// Creates new aym instance.
106    ///
107    /// `frequency` - frequency of the sound chip in Hz
108    /// `sample_rate` - target device sound sample rate
109    fn new(chip: SoundChip, mode: AyMode, frequency: usize, sample_rate: usize) -> Self;
110    /// Write value to the sound chip register. `address` should be in `[0..AY_REGISTER_COUNT]`
111    fn write_register(&mut self, address: u8, value: u8);
112    /// Generates next sound sample
113    fn next_sample(&mut self) -> StereoSample<Self::SoundSample>;
114}
aym/lib.rs

aym/
lib.rs
