fluffl 0.0.1

A cross-platform multimedia layer that exposes opengl,sockets,and audio utilities for desktop and broswer
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87

//the dektop implementation of sound is in the sdl2_audio module 
#[cfg(feature = "desktop")]
#[path = "./audio/sdl2_audio.rs"]
pub mod audio_util;

//the wasm(javascript) implementation for sound playback is in the web_audio module
#[cfg(feature = "web")]
#[path = "./audio/web_audio.rs"]
pub mod audio_util;

/// When playing/generating sound a callback will be required and it will need to be of this format.
pub type DeviceCB<State> = fn(&mut State, &mut [f32]);

/// Platform specific code awaits
pub use audio_util::*;
/// A trait used to define properties of the sound before playing
pub trait GenericAudioSpecs {
    fn sample_rate(&self) -> Option<u32>;
    fn bits_per_sample(&self) -> Option<u32>;
    fn channels(&self) ->Option<u32>;
}

/// A POD-ish struct for defining properties of the sound we with to play \
/// If one of the fields isn't defined it will fallback to a somewhat sane default value
pub struct DesiredSpecs {
    pub sample_rate: Option<u32>,
    pub channels: Option<u32>,
    pub buffer_size: Option<u32>,
}
impl DesiredSpecs {
    #[allow(dead_code)]
    fn get_specs(&self) -> (u32, usize, usize) {
        (
            self.sample_rate.unwrap_or(48000),
            self.channels.unwrap_or(2) as usize,
            self.buffer_size.unwrap_or(1024) as usize,
        )
    }
}

/// The core of `AudioDeviceCore` has common resources all platform-specific implementations will need. \
/// Creating this object is not enough to play sound. We will need to convert this into a `FlufflAudioDeviceContex`\
/// This struct is mostly used as a way to setup state, define a callback and specify things like channels, frequency, etc.\
/// Look at the examples for a complete example on how to do this.
pub struct AudioDeviceCore<Callback, State> {
    cb: Option<Callback>,
    state: Option<State>,
    desired_specs: DesiredSpecs,
}

impl<Callback, State> AudioDeviceCore<Callback, State>
where
    Callback: FnMut(&mut State, &mut [f32]) + Copy + 'static,
    State: 'static,
{
    pub fn new() -> Self {
        Self {
            cb: None,
            state: None,
            desired_specs: DesiredSpecs {
                sample_rate: None,
                channels: None,
                buffer_size: None,
            },
        }
    }
    ///A callback is needed to supply the audio backend with sound samples.
    ///Sound samples are expected to be interleaved-pcm 
    pub fn with_callback(mut self, cb: Callback) -> Self {
        self.cb = Some(cb);
        self
    }

    pub fn with_state(mut self, state: State) -> Self {
        self.state = Some(state);
        self
    }

    pub fn with_specs(mut self, specs: DesiredSpecs) -> Self {
        self.desired_specs = specs;
        self
    }

    pub fn callback(&self) -> Callback {
        self.cb.unwrap()
    }
}