Translate and scale a ray

This commit is contained in:
Savanni D'Gerinel 2024-06-23 14:13:02 -04:00
parent 8e4f6b06e6
commit af7d8680a0
1 changed files with 42 additions and 16 deletions

View File

@ -1,7 +1,6 @@
use crate::types::{Matrix, Point, Sphere, Vector};
use std::cmp::Ordering;
use crate::types::{Point, Sphere, Vector};
#[derive(Clone, Debug, PartialEq)]
pub struct Intersection<'a> {
t: f64,
@ -10,7 +9,7 @@ pub struct Intersection<'a> {
pub struct Intersections<'a>(Vec<Intersection<'a>>);
impl <'a> Intersections<'a> {
impl<'a> Intersections<'a> {
pub fn len(&'a self) -> usize {
self.0.len()
}
@ -20,14 +19,14 @@ impl <'a> Intersections<'a> {
}
}
impl <'a> std::ops::Index<usize> for Intersections<'a> {
impl<'a> std::ops::Index<usize> for Intersections<'a> {
type Output = Intersection<'a>;
fn index(&self, idx: usize) -> &Intersection<'a> {
&self.0[idx]
}
}
impl <'a> From<Vec<Intersection<'a>>> for Intersections<'a> {
impl<'a> From<Vec<Intersection<'a>>> for Intersections<'a> {
fn from(mut v: Vec<Intersection<'a>>) -> Self {
v.sort_by(|l, r| l.t.partial_cmp(&r.t).unwrap_or(Ordering::Equal));
Self(v)
@ -65,13 +64,22 @@ impl Ray {
vec![
Intersection { t: t1, object: &s },
Intersection { t: t2, object: &s },
].into()
]
.into()
}
pub fn transform(&self, m: Matrix) -> Self {
Self {
origin: m.clone() * self.origin,
direction: m * self.direction,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::transforms::{scaling, translation};
#[test]
fn computing_point_from_distance() {
@ -135,8 +143,8 @@ mod tests {
#[test]
fn hit_all_intersections_are_positive() {
let s = Sphere::new();
let i1 = Intersection{ t: 1., object: &s };
let i2 = Intersection{ t: 2., object: &s };
let i1 = Intersection { t: 1., object: &s };
let i2 = Intersection { t: 2., object: &s };
let xs = Intersections::from(vec![i1.clone(), i2]);
assert_eq!(xs.hit(), Some(&i1));
@ -145,8 +153,8 @@ mod tests {
#[test]
fn hit_some_intersections_are_negative() {
let s = Sphere::new();
let i1 = Intersection{ t: -1., object: &s };
let i2 = Intersection{ t: 1., object: &s };
let i1 = Intersection { t: -1., object: &s };
let i2 = Intersection { t: 1., object: &s };
let xs = Intersections::from(vec![i1, i2.clone()]);
assert_eq!(xs.hit(), Some(&i2));
@ -155,8 +163,8 @@ mod tests {
#[test]
fn hit_all_intersections_are_negative() {
let s = Sphere::new();
let i1 = Intersection{ t: -2., object: &s };
let i2 = Intersection{ t: -1., object: &s };
let i1 = Intersection { t: -2., object: &s };
let i2 = Intersection { t: -1., object: &s };
let xs = Intersections::from(vec![i1, i2]);
assert_eq!(xs.hit(), None);
@ -165,12 +173,30 @@ mod tests {
#[test]
fn hit_is_always_lowest_nonnegative() {
let s = Sphere::new();
let i1 = Intersection{ t: 5., object: &s };
let i2 = Intersection{ t: 7., object: &s };
let i3 = Intersection{ t: -3., object: &s };
let i4 = Intersection{ t: 2., object: &s };
let i1 = Intersection { t: 5., object: &s };
let i2 = Intersection { t: 7., object: &s };
let i3 = Intersection { t: -3., object: &s };
let i4 = Intersection { t: 2., object: &s };
let xs = Intersections::from(vec![i1, i2, i3, i4.clone()]);
assert_eq!(xs.hit(), Some(&i4));
}
#[test]
fn translate_a_ray() {
let r = Ray::new(Point::new(1., 2., 3.), Vector::new(0., 1., 0.));
let m = translation(3., 4., 5.);
let r2 = r.transform(m);
assert_eq!(r2.origin, Point::new(4., 6., 8.));
assert_eq!(r2.direction, Vector::new(0., 1., 0.));
}
#[test]
fn scale_a_ray() {
let r = Ray::new(Point::new(1., 2., 3.), Vector::new(0., 1., 0.));
let m = scaling(2., 3., 4.);
let r2 = r.transform(m);
assert_eq!(r2.origin, Point::new(2., 6., 12.));
assert_eq!(r2.direction, Vector::new(0., 3., 0.,));
}
}