logo
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137

// Copyright Jeron A. Lau 2017-2018.
// Copyright Douglas Lau 2017
// Dual-licensed under either the MIT License or the Boost Software License,
// Version 1.0.  (See accompanying file LICENSE_1_0.txt or copy at
// https://www.boost.org/LICENSE_1_0.txt)

use std::{ fmt, ops };
use *;

/// Single-precision bounding box
#[derive(Clone, Copy)]
pub struct BBox {
	pub(crate) min: Vector,
	pub(crate) max: Vector,
}

impl fmt::Debug for BBox {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		write!(f, "{:?} → {:?}", self.min, self.max)
	}
}

impl ops::Sub<Vector> for BBox {
	type Output = BBox;

	fn sub(self, other: Vector) -> Self::Output {
		BBox::new(self.min - other, self.max - other)
	}
}

impl ops::Add<Vector> for BBox {
	type Output = BBox;

	fn add(self, other: Vector) -> Self::Output {
		BBox::new(self.min + other, self.max + other)
	}
}

impl Into<BCube> for BBox {
	fn into(self) -> BCube {
		let span = self.max - self.min;

		BCube {
			center: self.center(),
			half_len: span.x.max(span.y).max(span.z) / 2.0,
		}
	}
}

impl BBox {
	/// Create an new `BBox` at position `p`.
	pub fn new(min: Vector, max: Vector) -> BBox {
		assert!(min.x <= max.x);
		assert!(min.y <= max.y);
		assert!(min.z <= max.z);

		BBox { min, max }
	}

	/// Check if `BBox` collides with `other` `BBox`.
	pub fn collide(&self, other: BBox) -> bool {
		   other.max.x >= self.min.x
		&& self.max.x >= other.min.x
		&& other.max.y >= self.min.y
		&& self.max.y >= other.min.y
		&& other.max.z >= self.min.z
		&& self.max.z >= other.min.z
	}

	/// Check if `BBox` collides with `BCube`.
	pub fn collide_bcube(&self, bcube: BCube) -> bool {
		let (max, min) = bcube.to_point_pair();
		self.collide(BBox::new(min, max))
	}

	/// Get which sides are the farthest away from the bbox (to extend).
	pub(crate) fn bcube_sides(&self, bcube: BCube) -> (bool, bool, bool) {
		let (max, min) = bcube.to_point_pair();
		let cube = BBox::new(min, max);

		let lt_dist = self.max.x - cube.max.x;
		let rt_dist = cube.min.x - self.min.x;
		let up_dist = self.max.y - cube.max.y;
		let dn_dist = cube.min.y - self.min.y;
		let nr_dist = self.max.z - cube.max.z;
		let fr_dist = cube.min.z - self.min.z;

		(rt_dist <= lt_dist, dn_dist <= up_dist, fr_dist <= nr_dist)
	}

	/// Check if `BBox` collides with point `p`.
	pub fn collide_vec3(&self, p: Vector) -> bool {
		(p.x >= self.min.x) &&
		(p.x <= self.max.x) &&
		(p.y >= self.min.y) &&
		(p.y <= self.max.y) &&
		(p.z >= self.min.z) &&
		(p.z <= self.max.z)
	}

	/// Get all 8 points of the `BBox`.
	pub fn all_points(&self) -> [Vector; 8] {
		[
			Vector::new(self.min.x, self.min.y, self.min.z),
			Vector::new(self.min.x, self.min.y, self.max.z),
			Vector::new(self.min.x, self.max.y, self.min.z),
			Vector::new(self.min.x, self.max.y, self.max.z),
			Vector::new(self.max.x, self.min.y, self.min.z),
			Vector::new(self.max.x, self.min.y, self.max.z),
			Vector::new(self.max.x, self.max.y, self.min.z),
			Vector::new(self.max.x, self.max.y, self.max.z),
		]
	}

	/// Get all 6 sides of the `BBox` as points.
	pub fn side_points(&self) -> [Vector; 6] {
		let center = self.center();

		[
			Vector::new(self.min.x, center.y, center.z),
			Vector::new(center.x, self.min.y, center.z),
			Vector::new(center.x, center.y, self.min.z),
			Vector::new(self.max.x, center.y, center.z),
			Vector::new(center.x, self.max.y, center.z),
			Vector::new(center.x, center.y, self.max.z),
		]
	}

	/// Get the center of the `BBox`.
	pub fn center(&self) -> Vector {
		Vector::new(
			(self.min.x + self.max.x) / 2.0,
			(self.min.y + self.max.y) / 2.0,
			(self.min.z + self.max.z) / 2.0,
		)
	}
}