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
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131

mod midi;
mod low;
mod font;
mod loader;
mod reverb;
mod chorus;
mod count;
mod params;
mod gen;
mod tuning;
mod misc;
mod write;

pub use self::tuning::TuningIter;
pub use self::write::IsSamples;

use crate::{ffi, Settings, SettingsRef, Result, result_from_ptr};

/**
The synth object

You create a new synthesizer with `Synth::new()`.
Use the settings structure to specify the synthesizer characteristics.

You have to load a SoundFont in order to hear any sound.
For that you use the `Synth::sfload()` function.

You can use the audio driver functions described below to open
the audio device and create a background audio thread.

The API for sending MIDI events is probably what you expect:
`Synth::noteon()`, `Synth::noteoff()`, ...
 */
pub struct Synth {
    handle: *mut ffi::fluid_synth_t,
}

unsafe impl Send for Synth {}

impl Synth {
    /**
    Creates a new synthesizer object.

    As soon as the synthesizer is created, it will start playing.
     */
    pub fn new(settings: Settings) -> Result<Self> {
        result_from_ptr(unsafe { ffi::new_fluid_synth(settings.into_ptr()) })
            .map(|handle| Self { handle })
    }

    /**
    Set synth sample rate
     */
    pub fn set_sample_rate(&self, sample_rate: f32) {
        unsafe { ffi::fluid_synth_set_sample_rate(self.handle, sample_rate); }
    }

    /**
    Get a reference to the settings of the synthesizer.
     */
    pub fn get_settings(&self) -> SettingsRef<'_> {
        SettingsRef::from_ptr(unsafe { ffi::fluid_synth_get_settings(self.handle) })
    }
}

impl Drop for Synth {
    fn drop(&mut self) {
        let _settings = Settings::from_ptr(unsafe { ffi::fluid_synth_get_settings(self.handle) });
        unsafe { ffi::delete_fluid_synth(self.handle); }
    }
}

#[cfg(test)]
mod test {
    use std::{
        io::Write,
        fs::File,
    };
    use byte_slice_cast::AsByteSlice;
    use super::{Settings, Synth};

    #[test]
    fn synth_sf2() {
        let mut pcm = File::create("Boomwhacker.sf2.pcm").unwrap();

        let settings = Settings::new().unwrap();

        let synth = Synth::new(settings).unwrap();

        synth.sfload("../sf_/Boomwhacker.sf2", true).unwrap();

        let mut samples = [0f32; 44100 * 2];

        synth.note_on(0, 60, 127).unwrap();

        synth.write(samples.as_mut()).unwrap();
        pcm.write(samples.as_byte_slice()).unwrap();

        synth.note_off(0, 60).unwrap();

        synth.write(samples.as_mut()).unwrap();
        pcm.write(samples.as_byte_slice()).unwrap();

        drop(synth);
    }

    #[test]
    fn synth_sf3() {
        let mut pcm = File::create("Boomwhacker.sf3.pcm").unwrap();

        let settings = Settings::new().unwrap();

        let synth = Synth::new(settings).unwrap();

        synth.sfload("../sf_/Boomwhacker.sf3", true).unwrap();

        let mut samples = [0f32; 44100 * 2];

        synth.note_on(0, 60, 127).unwrap();

        synth.write(samples.as_mut()).unwrap();
        pcm.write(samples.as_byte_slice()).unwrap();

        synth.note_off(0, 60).unwrap();

        synth.write(samples.as_mut()).unwrap();
        pcm.write(samples.as_byte_slice()).unwrap();

        drop(synth);
    }
}