phys_raycast/shapes/
cuboid.rs

1// Copyright (C) 2020-2025 phys-raycast authors. All Rights Reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use phys_geom::math::{Real, *};
16use phys_geom::shape::Cuboid;
17use phys_geom::ComputeAabb3;
18
19use crate::{Raycast, RaycastHitResult};
20
21impl Raycast for Cuboid {
22    fn raycast(
23        &self,
24        local_ray: phys_geom::Ray,
25        max_distance: Real,
26        discard_inside_hit: bool,
27    ) -> Option<RaycastHitResult> {
28        let one_over_direction = local_ray.one_over_direction();
29        let aabb = self.compute_aabb();
30
31        if let Some((entry, max_entry)) = aabb.raycast_by_one_over_direction_impl(
32            local_ray.origin,
33            one_over_direction,
34            max_distance,
35        ) {
36            if max_entry <= 0.0 {
37                if discard_inside_hit {
38                    return None;
39                }
40                return Some(RaycastHitResult {
41                    distance: 0.0,
42                    normal: -local_ray.direction,
43                });
44            }
45
46            let mut normal: UnitVec3;
47            let inverse;
48
49            #[allow(clippy::float_cmp)]
50            // Logic of raycast_by_one_over_direction_impl ensured we can use == here.
51            if entry.x == max_entry {
52                normal = Vec3::x_axis();
53                inverse = local_ray.direction.x > 0.0;
54            } else if entry.y == max_entry {
55                normal = Vec3::y_axis();
56                inverse = local_ray.direction.y > 0.0;
57            } else {
58                normal = Vec3::z_axis();
59                inverse = local_ray.direction.z > 0.0;
60            }
61
62            if inverse {
63                normal = -normal;
64            }
65
66            Some(RaycastHitResult {
67                distance: max_entry,
68                normal,
69            })
70        } else {
71            None
72        }
73    }
74}
75
76#[cfg(test)]
77mod tests {
78    use phys_geom::math::*;
79    use phys_geom::Ray;
80
81    use super::*;
82    #[test]
83    fn test_raycast() {
84        let cuboid = Cuboid::new(Vec3::new(1.0, 1.0, 1.0) * 2.0);
85        let ray_z = Ray::new_with_vec3(Point3::new(0.0, 0.0, 2.0), Vec3::new(0.0, 0.0, -1.0));
86        assert_eq!(
87            cuboid.raycast(ray_z, 5.0, false),
88            Some(RaycastHitResult {
89                distance: 1.0,
90                normal: UnitVec3::new_normalize(Vec3::new(0.0, 0.0, 1.0)),
91            })
92        );
93
94        assert_eq!(cuboid.raycast(ray_z, 0.5, false), None);
95
96        assert_eq!(
97            cuboid.raycast(
98                Ray::new_with_vec3(Point3::new(2.0, 0.0, 0.0), Vec3::new(-1.0, 0.0, 0.0)),
99                5.0,
100                false
101            ),
102            Some(RaycastHitResult {
103                distance: 1.0,
104                normal: UnitVec3::new_normalize(Vec3::new(1.0, 0.0, 0.0)),
105            })
106        );
107
108        assert_eq!(
109            cuboid.raycast(
110                Ray::new_with_vec3(Point3::new(0.0, 2.0, 0.0), Vec3::new(0.0, -1.0, 0.0)),
111                5.0,
112                false
113            ),
114            Some(RaycastHitResult {
115                distance: 1.0,
116                normal: Vec3::y_axis(),
117            })
118        );
119
120        assert_eq!(
121            cuboid.raycast(
122                Ray::new_with_vec3(Point3::new(-2.0, 0.0, 0.0), Vec3::new(1.0, 0.0, 0.0)),
123                5.0,
124                false
125            ),
126            Some(RaycastHitResult {
127                distance: 1.0,
128                normal: -Vec3::x_axis(),
129            })
130        );
131
132        assert_eq!(
133            cuboid.raycast(
134                Ray::new_with_vec3(Point3::new(0.0, -2.0, 0.0), Vec3::new(0.0, 1.0, 0.0)),
135                5.0,
136                false
137            ),
138            Some(RaycastHitResult {
139                distance: 1.0,
140                normal: -Vec3::y_axis(),
141            })
142        );
143
144        assert_eq!(
145            cuboid.raycast(
146                Ray::new_with_vec3(Point3::new(0.0, 0.0, -2.0), Vec3::new(0.0, 0.0, 1.0)),
147                5.0,
148                false
149            ),
150            Some(RaycastHitResult {
151                distance: 1.0,
152                normal: -Vec3::z_axis(),
153            })
154        );
155
156        {
157            let ray = Ray::new_with_vec3(Point3::new(0.0, 0.0, 2.0), Vec3::new(3.0, 0.0, -2.0));
158            assert_eq!(cuboid.raycast(ray, 10.0, false), None);
159        }
160    }
161
162    #[test]
163    fn test_raycast_surface() {
164        let cuboid = Cuboid::new(Vec3::new(1.0, 1.0, 1.0) * 2.0);
165        let ray = Ray::new_with_vec3(Point3::new(0.0, 0.0, 1.0), Vec3::new(0.0, 0.0, 1.0));
166        assert_eq!(cuboid.raycast(ray, 10.0, true), None);
167        assert_eq!(
168            cuboid.raycast(ray, 10.0, false),
169            Some(RaycastHitResult {
170                distance: 0.0,
171                normal: -ray.direction,
172            })
173        );
174    }
175
176    // The origin of the ray is inside the cube.
177    #[test]
178    fn test_raycast_inner() {
179        let cuboid = Cuboid::new(Vec3::new(1.0, 1.0, 1.0) * 2.0);
180        let ray = Ray::new_with_vec3(Point3::new(0.0, 0.0, 0.0), Vec3::new(0.0, 0.0, -1.0));
181        assert_eq!(
182            cuboid.raycast(ray, 5.0, false),
183            Some(RaycastHitResult {
184                distance: 0.0,
185                normal: -ray.direction,
186            })
187        );
188
189        assert_eq!(cuboid.raycast(ray, 5.0, true), None);
190    }
191}
phys_raycast/shapes/cuboid.rs

phys_raycast/shapes/
cuboid.rs
