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shapes: move tests from doctest to unit.

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This commit is contained in:
Bill Thiede 2021-07-30 20:58:05 -07:00
parent 5d6b3e6d57
commit 135a519526
1 changed files with 322 additions and 325 deletions
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647
rtchallenge/src/shapes.rs
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@ -57,64 +57,20 @@ pub struct Shape {
} }
/// Short hand for creating a ShapeBuilder with a plane geometry. /// Short hand for creating a ShapeBuilder with a plane geometry.
///
/// # Examples
/// ```
/// use rtchallenge::shapes::{plane, Shape};
/// # fn main() -> Result<(), Box<std::error::Error>> {
/// assert_eq!(plane().build()?, Shape::plane());
/// # Ok(())
/// # }
/// ```
pub fn plane() -> ShapeBuilder { pub fn plane() -> ShapeBuilder {
ShapeBuilder::plane() ShapeBuilder::plane()
} }
/// Short hand for creating a ShapeBuilder with a sphere geometry. /// Short hand for creating a ShapeBuilder with a sphere geometry.
///
/// # Examples
/// ```
/// use rtchallenge::shapes::{sphere, Shape};
///
/// # fn main() -> Result<(), Box<std::error::Error>> {
/// assert_eq!(sphere().build()?, Shape::sphere());
/// # Ok(())
/// # }
/// ```
pub fn sphere() -> ShapeBuilder { pub fn sphere() -> ShapeBuilder {
ShapeBuilder::sphere() ShapeBuilder::sphere()
} }
/// Short hand for creating a ShapeBuilder with a test shape geometry. /// Short hand for creating a ShapeBuilder with a test shape geometry.
///
/// # Examples
/// ```
/// use rtchallenge::shapes::{test_shape, Shape};
///
/// # fn main() -> Result<(), Box<std::error::Error>> {
/// assert_eq!(test_shape().build()?, Shape::test_shape());
/// # Ok(())
/// # }
/// ```
pub fn test_shape() -> ShapeBuilder { pub fn test_shape() -> ShapeBuilder {
ShapeBuilder::test_shape() ShapeBuilder::test_shape()
} }
/// Helper for producing a sphere with a glassy material. /// Helper for producing a sphere with a glassy material.
///
/// # Examples
/// ```
/// use rtchallenge::{matrices::identity, shapes::glass_sphere};
///
/// # fn main() -> Result<(), Box<dyn std::error::Error>> {
///
/// let s = glass_sphere().build()?;
/// assert_eq!(s.transform(), identity());
/// assert_eq!(s.material.transparency, 1.);
/// assert_eq!(s.material.refractive_index, 1.5);
///
/// # Ok(())
/// # }
/// ```
pub fn glass_sphere() -> ShapeBuilder { pub fn glass_sphere() -> ShapeBuilder {
ShapeBuilder::sphere().material( ShapeBuilder::sphere().material(
MaterialBuilder::default() MaterialBuilder::default()
@ -126,44 +82,14 @@ pub fn glass_sphere() -> ShapeBuilder {
} }
impl ShapeBuilder { impl ShapeBuilder {
/// Short hand for creating a ShapeBuilder with a plane geometry. /// Short hand for creating a ShapeBuilder with a plane geometry.
///
/// # Examples
/// ```
/// use rtchallenge::shapes::{plane, Shape};
///
/// # fn main() -> Result<(), Box<std::error::Error>> {
/// assert_eq!(plane().build()?, Shape::plane());
/// # Ok(())
/// # }
/// ```
pub fn plane() -> ShapeBuilder { pub fn plane() -> ShapeBuilder {
ShapeBuilder::default().geometry(Geometry::Plane) ShapeBuilder::default().geometry(Geometry::Plane)
} }
/// Short hand for creating a ShapeBuilder with a sphere geometry. /// Short hand for creating a ShapeBuilder with a sphere geometry.
///
/// # Examples
/// ```
/// use rtchallenge::shapes::{sphere, Shape};
///
/// # fn main() -> Result<(), Box<std::error::Error>> {
/// assert_eq!(sphere().build()?, Shape::sphere());
/// # Ok(())
/// # }
/// ```
pub fn sphere() -> ShapeBuilder { pub fn sphere() -> ShapeBuilder {
ShapeBuilder::default().geometry(Geometry::Sphere) ShapeBuilder::default().geometry(Geometry::Sphere)
} }
/// Short hand for creating a ShapeBuilder with a test shape geometry. /// Short hand for creating a ShapeBuilder with a test shape geometry.
///
/// # Examples
/// ```
/// use rtchallenge::shapes::{test_shape, Shape};
///
/// # fn main() -> Result<(), Box<std::error::Error>> {
/// assert_eq!(test_shape().build()?, Shape::test_shape());
/// # Ok(())
/// # }
/// ```
pub fn test_shape() -> ShapeBuilder { pub fn test_shape() -> ShapeBuilder {
ShapeBuilder::default().geometry(Geometry::TestShape(Arc::new(Mutex::new( ShapeBuilder::default().geometry(Geometry::TestShape(Arc::new(Mutex::new(
TestData::default(), TestData::default(),
@ -187,24 +113,6 @@ impl Default for Shape {
impl Shape { impl Shape {
/// Create a test shape useful for debugging. /// Create a test shape useful for debugging.
///
/// # Examples
/// ```
/// use rtchallenge::{materials::Material, matrices::Matrix4x4, shapes::Shape};
///
/// let mut s = Shape::test_shape();
/// // The default transform.
/// assert_eq!(s.transform(), Matrix4x4::identity());
/// // The default material.
/// assert_eq!(s.material, Material::default());
/// // Assigning a material.
/// let mut m = Material {
/// ambient: 1.,
/// ..Material::default()
/// };
/// s.material = m.clone();
/// assert_eq!(s.material, m);
/// ```
pub fn test_shape() -> Shape { pub fn test_shape() -> Shape {
Shape { Shape {
transform: Matrix4x4::identity(), transform: Matrix4x4::identity(),
@ -214,28 +122,6 @@ impl Shape {
} }
} }
/// # Examples /// # Examples
/// ```
/// use rtchallenge::{materials::Material, matrices::Matrix4x4, shapes::Shape};
///
/// // A sphere's default transform is the identity matrix.
/// let s = Shape::sphere();
/// assert_eq!(s.transform(), Matrix4x4::identity());
///
/// // It can be changed by directly setting the transform member.
/// let mut s = Shape::sphere();
/// let t = Matrix4x4::translation(2., 3., 4.);
/// s.set_transform(t.clone());
/// assert_eq!(s.transform(), t);
///
/// // Default Sphere has the default material.
/// assert_eq!(s.material, Material::default());
/// // It can be overridden.
/// let mut s = Shape::sphere();
/// let mut m = Material::default();
/// m.ambient = 1.;
/// s.material = m.clone();
/// assert_eq!(s.material, m);
/// ```
pub fn sphere() -> Shape { pub fn sphere() -> Shape {
Shape { Shape {
transform: Matrix4x4::identity(), transform: Matrix4x4::identity(),
@ -253,100 +139,6 @@ impl Shape {
} }
} }
/// Find the normal at the point on the sphere. /// Find the normal at the point on the sphere.
///
/// # Examples
/// ```
/// use rtchallenge::{
/// float::consts::PI, materials::Material, matrices::Matrix4x4, shapes::Shape, tuples::Tuple,
/// Float,
/// };
///
/// // Computing the normal on a translated shape.
/// let mut s = Shape::test_shape();
/// s.set_transform(Matrix4x4::translation(0., 1., 0.));
/// let n = s.normal_at(Tuple::point(0., 1.70711, -0.70711));
/// assert_eq!(n, Tuple::vector(0., 0.70711, -0.70711));
///
/// // Computing the normal on a transform shape.
/// let mut s = Shape::test_shape();
/// s.set_transform(Matrix4x4::scaling(1., 0.5, 1.) * Matrix4x4::rotation_z(PI / 5.));
/// let n = s.normal_at(Tuple::point(
/// 0.,
/// (2. as Float).sqrt() / 2.,
/// -(2. as Float).sqrt() / 2.,
/// ));
/// assert_eq!(n, Tuple::vector(0., 0.97014, -0.24254));
///
/// // Normal on X-axis
/// let s = Shape::sphere();
/// let n = s.normal_at(Tuple::point(1., 0., 0.));
/// assert_eq!(n, Tuple::vector(1., 0., 0.));
///
/// // Normal on Y-axis
/// let s = Shape::sphere();
/// let n = s.normal_at(Tuple::point(0., 1., 0.));
/// assert_eq!(n, Tuple::vector(0., 1., 0.));
///
/// // Normal on Z-axis
/// let s = Shape::sphere();
/// let n = s.normal_at(Tuple::point(0., 0., 1.));
/// assert_eq!(n, Tuple::vector(0., 0., 1.));
///
/// // Normal on a sphere at a nonaxial point.
/// let s = Shape::sphere();
/// let n = s.normal_at(Tuple::point(
/// (3. as Float).sqrt() / 3.,
/// (3. as Float).sqrt() / 3.,
/// (3. as Float).sqrt() / 3.,
/// ));
/// assert_eq!(
/// n,
/// Tuple::vector(
/// (3. as Float).sqrt() / 3.,
/// (3. as Float).sqrt() / 3.,
/// (3. as Float).sqrt() / 3.,
/// )
/// );
/// // Normals returned are normalized.
/// let s = Shape::sphere();
/// let n = s.normal_at(Tuple::point(
/// (3. as Float).sqrt() / 3.,
/// (3. as Float).sqrt() / 3.,
/// (3. as Float).sqrt() / 3.,
/// ));
/// assert_eq!(n, n.normalize());
///
/// // Compute the normal on a translated sphere.
/// let mut s = Shape::sphere();
/// s.set_transform(Matrix4x4::translation(0., 1., 0.));
/// let n = s.normal_at(Tuple::point(0., 1.70711, -0.70711));
/// assert_eq!(n, Tuple::vector(0., 0.70711, -0.70711));
///
/// // Compute the normal on a transformed sphere.
/// let mut s = Shape::sphere();
/// s.set_transform(Matrix4x4::scaling(1., 0.5, 1.) * Matrix4x4::rotation_z(PI / 5.));
/// let n = s.normal_at(Tuple::point(
/// 0.,
/// (2. as Float).sqrt() / 2.,
/// -(2. as Float).sqrt() / 2.,
/// ));
/// assert_eq!(n, Tuple::vector(0., 0.97014, -0.24254));
///
/// // Normal of a plane is constant everywhere.
/// let p = Shape::plane();
/// assert_eq!(
/// p.normal_at(Tuple::point(0., 0., 0.)),
/// Tuple::vector(0., 1., 0.)
/// );
/// assert_eq!(
/// p.normal_at(Tuple::point(10., 0., -10.)),
/// Tuple::vector(0., 1., 0.)
/// );
/// assert_eq!(
/// p.normal_at(Tuple::point(-5., 0., 150.)),
/// Tuple::vector(0., 1., 0.)
/// );
/// ```
pub fn normal_at(&self, world_point: Tuple) -> Tuple { pub fn normal_at(&self, world_point: Tuple) -> Tuple {
let object_point = self.inverse_transform * world_point; let object_point = self.inverse_transform * world_point;
let object_normal = match self.geometry { let object_normal = match self.geometry {
@ -377,123 +169,6 @@ impl Shape {
} }
/// Intersect a ray with a shapes. /// Intersect a ray with a shapes.
///
/// # Examples
/// ```
/// use rtchallenge::{
/// intersections::{Intersection, Intersections},
/// matrices::Matrix4x4,
/// rays::Ray,
/// shapes::{intersect, Geometry, Shape},
/// tuples::Tuple,
/// };
///
/// // Intersecting a scaled shape with a ray.
/// let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
/// let mut s = Shape::test_shape();
/// s.set_transform(Matrix4x4::scaling(2., 2., 2.));
/// let xs = intersect(&s, &r);
/// if let Geometry::TestShape(data) = s.geometry() {
/// if let Some(ray) = &data.lock().unwrap().saved_ray {
/// assert_eq!(ray.origin, Tuple::point(0., 0., -2.5));
/// assert_eq!(ray.direction, Tuple::vector(0., 0., 0.5));
/// } else {
/// panic!("ray wasn't set");
/// };
/// } else {
/// panic!("test_shape returned a non-TestShape geometry")
/// };
///
/// // Intersecting a translated shape with a ray.
/// let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
/// let mut s = Shape::test_shape();
/// s.set_transform(Matrix4x4::translation(5., 0., 0.));
/// let xs = intersect(&s, &r);
/// if let Geometry::TestShape(data) = s.geometry() {
/// if let Some(ray) = &data.lock().unwrap().saved_ray {
/// assert_eq!(ray.origin, Tuple::point(-5., 0., -5.));
/// assert_eq!(ray.direction, Tuple::vector(0., 0., 1.));
/// } else {
/// panic!("ray wasn't set");
/// };
/// } else {
/// panic!("test_shape returned a non-TestShape geometry")
/// };
///
/// // A ray intersects a sphere in two points.
/// let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
/// let s = Shape::sphere();
/// let xs = intersect(&s, &r);
/// assert_eq!(
/// xs,
/// Intersections::new(vec![Intersection::new(4., &s), Intersection::new(6., &s)])
/// );
///
/// // A ray intersects a sphere at a tangent.
/// let r = Ray::new(Tuple::point(0., 2., -5.), Tuple::vector(0., 0., 1.));
/// let s = Shape::sphere();
/// let xs = intersect(&s, &r);
/// assert_eq!(xs, Intersections::default());
///
/// // A ray originates inside a sphere.
/// let r = Ray::new(Tuple::point(0., 0., 0.), Tuple::vector(0., 0., 1.));
/// let s = Shape::sphere();
/// let xs = intersect(&s, &r);
/// assert_eq!(
/// xs,
/// Intersections::new(vec![Intersection::new(-1., &s), Intersection::new(1., &s)])
/// );
///
/// // A sphere is behind a ray.
/// let r = Ray::new(Tuple::point(0., 0., 5.), Tuple::vector(0., 0., 1.));
/// let s = Shape::sphere();
/// let xs = intersect(&s, &r);
/// assert_eq!(
/// xs,
/// Intersections::new(vec![Intersection::new(-6., &s), Intersection::new(-4., &s)])
/// );
///
/// // Intersect a scaled sphere with a ray.
/// let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
/// let mut s = Shape::sphere();
/// s.set_transform(Matrix4x4::scaling(2., 2., 2.));
/// let xs = intersect(&s, &r);
/// assert_eq!(xs.len(), 2, "xs {:?}", xs);
/// assert_eq!(xs[0].t, 3., "xs {:?}", xs);
/// assert_eq!(xs[1].t, 7., "xs {:?}", xs);
///
/// // Intersect a translated sphere with a ray.
/// let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
/// let mut s = Shape::sphere();
/// s.set_transform(Matrix4x4::translation(5., 0., 0.));
/// let xs = intersect(&s, &r);
/// assert_eq!(xs.len(), 0);
///
/// // Intersect with a ray parallel to the plane.
/// let p = Shape::plane();
/// let r = Ray::new(Tuple::point(0., 10., 0.), Tuple::vector(0., 0., 1.));
/// let xs = intersect(&p, &r);
/// assert_eq!(xs.len(), 0);
///
/// // Intersect with a coplanar.
/// let r = Ray::new(Tuple::point(0., 0., 0.), Tuple::vector(0., 0., 1.));
/// let xs = intersect(&p, &r);
/// assert_eq!(xs.len(), 0);
///
/// // A ray intersecting a plane from above.
/// let r = Ray::new(Tuple::point(0., 1., 0.), Tuple::vector(0., -1., 0.));
/// let xs = intersect(&p, &r);
/// assert_eq!(xs.len(), 1);
/// assert_eq!(xs[0].t, 1.);
/// assert_eq!(xs[0].object, &p);
///
/// // A ray intersecting a plane from below.
/// let r = Ray::new(Tuple::point(0., -1., 0.), Tuple::vector(0., 1., 0.));
/// let xs = intersect(&p, &r);
/// assert_eq!(xs.len(), 1);
/// assert_eq!(xs[0].t, 1.);
/// assert_eq!(xs[0].object, &p);
/// ```
pub fn intersect<'s>(shape: &'s Shape, ray: &Ray) -> Intersections<'s> { pub fn intersect<'s>(shape: &'s Shape, ray: &Ray) -> Intersections<'s> {
let local_ray = ray.transform(shape.inverse_transform); let local_ray = ray.transform(shape.inverse_transform);
match shape.geometry { match shape.geometry {
@ -559,3 +234,325 @@ mod plane {
)]) )])
} }
} }
#[cfg(test)]
mod tests {
mod shape_builder {
use std::error::Error;
use crate::shapes::{plane, sphere, test_shape, Shape};
#[test]
fn plane_builder() -> Result<(), Box<dyn Error>> {
assert_eq!(plane().build()?, Shape::plane());
Ok(())
}
#[test]
fn sphere_builder() -> Result<(), Box<dyn Error>> {
assert_eq!(sphere().build()?, Shape::sphere());
Ok(())
}
#[test]
fn test_shape_builder() -> Result<(), Box<dyn Error>> {
assert_eq!(test_shape().build()?, Shape::test_shape());
Ok(())
}
}
mod shape {
use crate::{
materials::Material,
matrices::{identity, translation},
shapes::Shape,
};
#[test]
fn test_shape() {
let mut s = Shape::test_shape();
// The default transform.
assert_eq!(s.transform(), identity());
// The default material.
assert_eq!(s.material, Material::default());
// Assigning a material.
let m = Material {
ambient: 1.,
..Material::default()
};
s.material = m.clone();
assert_eq!(s.material, m);
}
#[test]
fn sphere() {
// A sphere's default transform is the identity matrix.
let s = Shape::sphere();
assert_eq!(s.transform(), identity());
// It can be changed by directly setting the transform member.
let mut s = Shape::sphere();
let t = translation(2., 3., 4.);
s.set_transform(t.clone());
assert_eq!(s.transform(), t);
// Default Sphere has the default material.
assert_eq!(s.material, Material::default());
// It can be overridden.
let mut s = Shape::sphere();
let mut m = Material::default();
m.ambient = 1.;
s.material = m.clone();
assert_eq!(s.material, m);
}
}
mod normal_at {
use crate::{float::consts::PI, matrices::Matrix4x4, shapes::Shape, tuples::Tuple, Float};
#[test]
fn compute_normal_on_translated_shape() {
// Computing the normal on a translated shape.
let mut s = Shape::test_shape();
s.set_transform(Matrix4x4::translation(0., 1., 0.));
let n = s.normal_at(Tuple::point(0., 1.70711, -0.70711));
assert_eq!(n, Tuple::vector(0., 0.70711, -0.70711));
}
#[test]
fn compute_normal_on_scaled_shape() {
// Computing the normal on a scaled shape.
let mut s = Shape::test_shape();
s.set_transform(Matrix4x4::scaling(1., 0.5, 1.) * Matrix4x4::rotation_z(PI / 5.));
let n = s.normal_at(Tuple::point(
0.,
(2. as Float).sqrt() / 2.,
-(2. as Float).sqrt() / 2.,
));
assert_eq!(n, Tuple::vector(0., 0.97014, -0.24254));
}
#[test]
fn sphere_normal_on_x_axis() {
// Normal on X-axis
let s = Shape::sphere();
let n = s.normal_at(Tuple::point(1., 0., 0.));
assert_eq!(n, Tuple::vector(1., 0., 0.));
}
#[test]
fn sphere_normal_on_y_axis() {
// Normal on Y-axis
let s = Shape::sphere();
let n = s.normal_at(Tuple::point(0., 1., 0.));
assert_eq!(n, Tuple::vector(0., 1., 0.));
}
#[test]
fn sphere_normal_on_z_axis() {
// Normal on Z-axis
let s = Shape::sphere();
let n = s.normal_at(Tuple::point(0., 0., 1.));
assert_eq!(n, Tuple::vector(0., 0., 1.));
}
#[test]
fn sphere_normal_non_axial() {
// Normal on a sphere at a nonaxial point.
let s = Shape::sphere();
let n = s.normal_at(Tuple::point(
(3. as Float).sqrt() / 3.,
(3. as Float).sqrt() / 3.,
(3. as Float).sqrt() / 3.,
));
assert_eq!(
n,
Tuple::vector(
(3. as Float).sqrt() / 3.,
(3. as Float).sqrt() / 3.,
(3. as Float).sqrt() / 3.,
)
);
}
#[test]
fn normals_are_normalized() {
// Normals returned are normalized.
let s = Shape::sphere();
let n = s.normal_at(Tuple::point(
(3. as Float).sqrt() / 3.,
(3. as Float).sqrt() / 3.,
(3. as Float).sqrt() / 3.,
));
assert_eq!(n, n.normalize());
}
#[test]
fn compute_normal_on_translated_sphere() {
// Compute the normal on a translated sphere.
let mut s = Shape::sphere();
s.set_transform(Matrix4x4::translation(0., 1., 0.));
let n = s.normal_at(Tuple::point(0., 1.70711, -0.70711));
assert_eq!(n, Tuple::vector(0., 0.70711, -0.70711));
}
#[test]
fn compute_normal_on_scaled_sphere() {
// Compute the normal on a transformed sphere.
let mut s = Shape::sphere();
s.set_transform(Matrix4x4::scaling(1., 0.5, 1.) * Matrix4x4::rotation_z(PI / 5.));
let n = s.normal_at(Tuple::point(
0.,
(2. as Float).sqrt() / 2.,
-(2. as Float).sqrt() / 2.,
));
assert_eq!(n, Tuple::vector(0., 0.97014, -0.24254));
}
#[test]
fn nomal_of_plane_constant() {
// Normal of a plane is constant everywhere.
let p = Shape::plane();
assert_eq!(
p.normal_at(Tuple::point(0., 0., 0.)),
Tuple::vector(0., 1., 0.)
);
assert_eq!(
p.normal_at(Tuple::point(10., 0., -10.)),
Tuple::vector(0., 1., 0.)
);
assert_eq!(
p.normal_at(Tuple::point(-5., 0., 150.)),
Tuple::vector(0., 1., 0.)
);
}
}
mod intersect {
use crate::{
intersections::{Intersection, Intersections},
matrices::Matrix4x4,
rays::Ray,
shapes::{intersect, Geometry, Shape},
tuples::Tuple,
};
#[test]
fn scaled_shape_with_ray() {
// Intersecting a scaled shape with a ray.
let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
let mut s = Shape::test_shape();
s.set_transform(Matrix4x4::scaling(2., 2., 2.));
let xs = intersect(&s, &r);
if let Geometry::TestShape(data) = s.geometry() {
if let Some(ray) = &data.lock().unwrap().saved_ray {
assert_eq!(ray.origin, Tuple::point(0., 0., -2.5));
assert_eq!(ray.direction, Tuple::vector(0., 0., 0.5));
} else {
panic!("ray wasn't set");
};
} else {
panic!("test_shape returned a non-TestShape geometry")
};
}
#[test]
fn translated_shape_with_ray() {
// Intersecting a translated shape with a ray.
let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
let mut s = Shape::test_shape();
s.set_transform(Matrix4x4::translation(5., 0., 0.));
let xs = intersect(&s, &r);
if let Geometry::TestShape(data) = s.geometry() {
if let Some(ray) = &data.lock().unwrap().saved_ray {
assert_eq!(ray.origin, Tuple::point(-5., 0., -5.));
assert_eq!(ray.direction, Tuple::vector(0., 0., 1.));
} else {
panic!("ray wasn't set");
};
} else {
panic!("test_shape returned a non-TestShape geometry")
};
}
#[test]
fn ray_intersects_sphere_two_points() {
// A ray intersects a sphere in two points.
let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
let s = Shape::sphere();
let xs = intersect(&s, &r);
assert_eq!(
xs,
Intersections::new(vec![Intersection::new(4., &s), Intersection::new(6., &s)])
);
}
#[test]
fn ray_intersects_at_tangent() {
// A ray intersects a sphere at a tangent.
let r = Ray::new(Tuple::point(0., 2., -5.), Tuple::vector(0., 0., 1.));
let s = Shape::sphere();
let xs = intersect(&s, &r);
assert_eq!(xs, Intersections::default());
}
#[test]
fn ray_originates_inside_sphere() {
// A ray originates inside a sphere.
let r = Ray::new(Tuple::point(0., 0., 0.), Tuple::vector(0., 0., 1.));
let s = Shape::sphere();
let xs = intersect(&s, &r);
assert_eq!(
xs,
Intersections::new(vec![Intersection::new(-1., &s), Intersection::new(1., &s)])
);
}
#[test]
fn sphere_behind_ray() {
// A sphere is behind a ray.
let r = Ray::new(Tuple::point(0., 0., 5.), Tuple::vector(0., 0., 1.));
let s = Shape::sphere();
let xs = intersect(&s, &r);
assert_eq!(
xs,
Intersections::new(vec![Intersection::new(-6., &s), Intersection::new(-4., &s)])
);
}
#[test]
fn ray_intersects_scaled_sphere() {
// Intersect a scaled sphere with a ray.
let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
let mut s = Shape::sphere();
s.set_transform(Matrix4x4::scaling(2., 2., 2.));
let xs = intersect(&s, &r);
assert_eq!(xs.len(), 2, "xs {:?}", xs);
assert_eq!(xs[0].t, 3., "xs {:?}", xs);
assert_eq!(xs[1].t, 7., "xs {:?}", xs);
}
#[test]
fn ray_intersects_translated_sphere() {
// Intersect a translated sphere with a ray.
let r = Ray::new(Tuple::point(0., 0., -5.), Tuple::vector(0., 0., 1.));
let mut s = Shape::sphere();
s.set_transform(Matrix4x4::translation(5., 0., 0.));
let xs = intersect(&s, &r);
assert_eq!(xs.len(), 0);
}
#[test]
fn ray_parallel_to_plane() {
// Intersect with a ray parallel to the plane.
let p = Shape::plane();
let r = Ray::new(Tuple::point(0., 10., 0.), Tuple::vector(0., 0., 1.));
let xs = intersect(&p, &r);
assert_eq!(xs.len(), 0);
}
#[test]
fn ray_coplanar_to_plane() {
// Intersect with a coplanar.
let p = Shape::plane();
let r = Ray::new(Tuple::point(0., 0., 0.), Tuple::vector(0., 0., 1.));
let xs = intersect(&p, &r);
assert_eq!(xs.len(), 0);
}
#[test]
fn ray_intersects_plane_from_above() {
// A ray intersecting a plane from above.
let p = Shape::plane();
let r = Ray::new(Tuple::point(0., 1., 0.), Tuple::vector(0., -1., 0.));
let xs = intersect(&p, &r);
assert_eq!(xs.len(), 1);
assert_eq!(xs[0].t, 1.);
assert_eq!(xs[0].object, &p);
}
#[test]
fn ray_intersects_plane_from_below() {
// A ray intersecting a plane from below.
let p = Shape::plane();
let r = Ray::new(Tuple::point(0., -1., 0.), Tuple::vector(0., 1., 0.));
let xs = intersect(&p, &r);
assert_eq!(xs.len(), 1);
assert_eq!(xs[0].t, 1.);
assert_eq!(xs[0].object, &p);
}
}
}