src/math/mod.rs


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pub mod rect;
pub use self::rect::*;

pub mod vec2;
pub use self::vec2::*;

/// Round a floating point number to the nearest step given by the step argument. For instance, if
/// the step is 0.5, then all numbers from 0.0 to 0.24999... will be 0., while all numbers from
/// 0.25 to 0.74999... will be 0.5 and so on.
pub fn round(num: f32, step: f32) -> f32 {
    // Only positive steps will be accepted.
    assert!(step > 0.);

    let lower_bound = ((num / step) as i32) as f32 * step;
    let upper_bound = lower_bound + step;

    // Compare the distances and prefer the smaller. If they are the same, prefer the upper bound.
    if (num - lower_bound) < (upper_bound - num) {
        lower_bound
    } else {
        upper_bound
    }
}