rtrace 1.0.0

A pet raytracer to test overall pseudo-performance and multi-threading
Documentation 
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//! A module implementing a Vector type which can be parametized to support different
//! floating point precision.

use std::ops::{Add, Sub, Mul};

pub type RFloat = f32;

#[derive(PartialEq, Clone, Copy, Default, Debug)]
pub struct Vector {
    pub x: RFloat,
    pub y: RFloat,
    pub z: RFloat,
}

impl Add for Vector {
    type Output = Vector;

    // Probably it will be optimized to not actually copy self and rhs for each call !
    #[inline(always)]
    fn add(self, rhs: Vector) -> Vector {
        Vector {
            x: self.x + rhs.x,
            y: self.y + rhs.y,
            z: self.z + rhs.z,
        }
    }
}

impl Sub for Vector {
    type Output = Vector;

    #[inline(always)]
    fn sub(self, rhs: Vector) -> Vector {
        Vector {
            x: self.x - rhs.x,
            y: self.y - rhs.y,
            z: self.z - rhs.z,
        }
    }
}

impl Mul for Vector {
    type Output = Vector;

    #[inline(always)]
    fn mul(self, rhs: Vector) -> Vector {
        Vector {
            x: self.x * rhs.x,
            y: self.y * rhs.y,
            z: self.z * rhs.z,
        }
    }
}

impl<'a> Vector {
    #[inline(always)]
    pub fn mulfed(&self, m: RFloat) -> Vector {
        Vector {
            x: self.x * m,
            y: self.y * m,
            z: self.z * m,
        }
    }

    // in ruby, you can use ! to signal it's in-place - here we have to find another way
    #[inline(always)]
    pub fn mulf(&'a mut self, m: RFloat) -> &'a mut Vector {
        self.x = self.x * m;
        self.y = self.y * m;
        self.z = self.z * m;
        self
    }

    // The dot product - should we keep going and use  &ref type as self ?
    // Or just keep copying self around as in sub, add, mul ?
    #[inline(always)]
    pub fn dot(&self, r: &Vector) -> RFloat {
        self.x * r.x + self.y * r.y + self.z * r.z
    }

    #[inline(always)]
    pub fn len(&self) -> RFloat {
        self.dot(self).sqrt()
    }

    #[inline(always)]
    pub fn normalize(&'a mut self) -> &'a mut Vector {
        let len = self.len();
        self.mulf(len.recip())
    }

    #[inline(always)]
    pub fn normalized(&self) -> Vector {
        self.mulfed(self.len().recip())
    }
}


#[cfg(test)]
mod tests {
    extern crate test;
    use std::default::Default;
    use super::*;

    #[test]
    fn basics() {
        let v32 = Vector {
            x: 5.0,
            y: 4.0,
            z: 0.0,
        };
        assert_eq!(v32.x, 5.0);
        assert_eq!(v32, v32);
        assert!(!(v32 != v32));
        {
            // This is a copyable type - if not, this assignment would fail
            let mut copy = v32;
            copy.x = 10.0;
        }

        let v64 = Vector {
            x: 1.0,
            y: 2.0,
            z: 3.0,
        };
        assert_eq!(v64.x, 1.0);


        // Addition
        let v = v32 + v32;
        assert_eq!(v.x, v32.x + v32.x);
        assert_eq!(v.y, v32.y + v32.y);
        assert_eq!(v.z, v32.z + v32.z);

        // Subtraction
        let v = v32 - v32;
        assert_eq!(v.x, 0.0);

        // Multiplication
        let v = v32 * v32;
        assert_eq!(v.x, v32.x * v32.x);

        let mut v = v32.mulfed(3.0);
        assert_eq!(v.x, v32.x * 3.0);

        v.mulf(2.0);
        assert_eq!(v.x, v32.x * 3.0 * 2.0);
    }

    #[test]
    fn default() {
        let v1: Vector = Default::default();
        let v2 = <Vector as Default>::default();
        assert_eq!(v1, v2);
    }

    #[test]
    fn normalize() {
        let v = Vector {
            x: 2.0,
            y: 0.0,
            z: 0.0,
        };
        assert_eq!(v.len(), 2.0);
        assert_eq!(v.normalized().len(), 1.0);

        let mut v = v;
        assert_eq!(v.normalize().len(), 1.0);

    }
}