vec.rs

1/// A three-component vector of f32.2#[derive(Clone, Copy, Debug, PartialEq)]3pub struct Vec3 {4    /// The x component.5    pub x: f32,6    /// The y component.7    pub y: f32,8    /// The z component.9    pub z: f32,10}1112impl std::ops::Add for Vec3 {13    type Output = Vec3;14    fn add(self, o: Vec3) -> Vec3 {15        Vec3::new(self.x + o.x, self.y + o.y, self.z + o.z)16    }17}1819impl std::ops::Sub for Vec3 {20    type Output = Vec3;21    fn sub(self, o: Vec3) -> Vec3 {22        Vec3::new(self.x - o.x, self.y - o.y, self.z - o.z)23    }24}2526impl Vec3 {27    /// Builds a vector from its components.28    pub fn new(x: f32, y: f32, z: f32) -> Vec3 {29        Vec3 { x, y, z }30    }31    /// Multiplies every component by the scalar.32    pub fn scale(self, s: f32) -> Vec3 {33        Vec3::new(self.x * s, self.y * s, self.z * s)34    }35    /// Returns the dot product of the two vectors.36    pub fn dot(self, o: Vec3) -> f32 {37        self.x * o.x + self.y * o.y + self.z * o.z38    }39    /// Returns the cross product, perpendicular to both vectors.40    ///41    /// ```42    /// use mrlyrs::math::space::Vec3;43    /// let n = Vec3::new(1.0, 0.0, 0.0).cross(Vec3::new(0.0, 1.0, 0.0));44    /// assert_eq!(n, Vec3::new(0.0, 0.0, 1.0));45    /// ```46    pub fn cross(self, o: Vec3) -> Vec3 {47        Vec3::new(48            self.y * o.z - self.z * o.y,49            self.z * o.x - self.x * o.z,50            self.x * o.y - self.y * o.x,51        )52    }53}5455#[cfg(test)]56mod tests {57    use super::*;5859    #[test]60    fn cross_is_perpendicular() {61        let a = Vec3::new(1.0, 2.0, 3.0);62        let b = Vec3::new(-2.0, 0.5, 1.0);63        let c = a.cross(b);64        assert!(c.dot(a).abs() < 1e-6);65        assert!(c.dot(b).abs() < 1e-6);66    }67}