rustysynth-ext 1.5.0

A SoundFont (sf2, sf3) MIDI synthesizer written in pure Rust (a fork of rustysynth)
Documentation 
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use std::f32::consts;

#[non_exhaustive]
pub(crate) struct SoundFontMath {}

impl SoundFontMath {
    pub(crate) const HALF_PI: f32 = consts::PI / 2_f32;
    pub(crate) const NON_AUDIBLE: f32 = 1.0e-3_f32;
    pub(crate) const LOG_NON_AUDIBLE: f32 = -6.907_755_4_f32;

    pub(crate) fn max(x: f32, y: f32) -> f32 {
        if x > y { x } else { y }
    }

    pub(crate) fn clamp(value: f32, min: f32, max: f32) -> f32 {
        if value < min {
            min
        } else if value > max {
            max
        } else {
            value
        }
    }

    pub(crate) fn timecents_to_seconds(x: f32) -> f32 {
        2_f32.powf((1_f32 / 1200_f32) * x)
    }

    pub(crate) fn cents_to_hertz(x: f32) -> f32 {
        8.176_f32 * 2_f32.powf((1_f32 / 1200_f32) * x)
    }

    pub(crate) fn cents_to_multiplying_factor(x: f32) -> f32 {
        2_f32.powf((1_f32 / 1200_f32) * x)
    }

    pub(crate) fn decibels_to_linear(x: f32) -> f32 {
        10_f32.powf(0.05_f32 * x)
    }

    pub(crate) fn linear_to_decibels(x: f32) -> f32 {
        20_f32 * x.log10()
    }

    pub(crate) fn key_number_to_multiplying_factor(cents: i32, key: i32) -> f32 {
        SoundFontMath::timecents_to_seconds((cents * (60 - key)) as f32)
    }

    pub(crate) fn exp_cutoff(x: f64) -> f64 {
        if x < SoundFontMath::LOG_NON_AUDIBLE as f64 {
            0_f64
        } else {
            x.exp()
        }
    }
}