mathpak 0.4.0

Rust Math Routines, a simple to use math focused library written in rust
Documentation 
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use crate::points::{point2::Point2, point::Point};

/// ! turn 3 points into a bezier curve

#[derive(Debug, Clone, Copy)]
pub struct Bezier {
    pub p0: Point2,
    pub p1: Point2,
    pub p2: Point2,
}

impl Bezier {
    pub fn new(p0: Point2, p1: Point2, p2: Point2) -> Self {
        Bezier { p0, p1, p2 }
    }

    pub fn get_point(&self, t: f64) -> Point2 {
        let inter_a =  self.p0.lerp(self.p1, t);
        let inter_b =  self.p1.lerp(self.p2, t);
        inter_a.lerp(inter_b, t)
    }

    /// Get a list of points along the bezier curve
    /// `resolution` is the number of points to generate, points are evenly spaced along the curve
    pub fn get_points(&self, resolution: usize) -> Vec<Point2> {
        let mut points = Vec::new();
        for i in 0..resolution {
            let t = i as f64 / (resolution - 1) as f64;
            points.push(self.get_point(t));
        }
        points
    }

    /// Update the points of the bezier curve without creating a new one
    /// if the same resolution is used, no new vector will be created
    pub fn update_points(&self, resolution: usize, points: &mut Vec<Point2>) {
        if resolution != points.len() {
            *points = Vec::with_capacity(resolution);
        }
        for i in 0..resolution {
            let t = i as f64 / (resolution - 1) as f64;
            points.push(self.get_point(t));
        }
    }

    /// Refresh the points of the bezier curve without creating a new one
    /// if the same resolution is used, no new vector will be created
    pub fn refresh(&self, points: &mut Vec<Point2>) {
        self.update_points(points.len(), points);
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_bezier() {
        let p0 = Point2::new(0.0, 0.0);
        let p1 = Point2::new(1.0, 1.0);
        let p2 = Point2::new(2.0, 0.0);
        let bezier = Bezier::new(p0, p1, p2);
        let points = bezier.get_points(5);
        assert_eq!(points.len(), 5);
        assert_eq!(points[0], p0);
        assert_eq!(points[4], p2);
    }
}