gemath 0.1.0

Type-safe game math with type-level units/spaces, typed angles, and explicit fallible ops (plus optional geometry/collision).
Documentation 
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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243

#![cfg(all(feature = "rect3", feature = "mat4"))]

use gemath::*;
use gemath::rect3::*;
use gemath::vec3::*;

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_rect3_new() {
        let r: Rect3<(),()> = Rect3::new(Vec3::new(1.0, 2.0, 3.0), Vec3::new(4.0, 5.0, 6.0));
        assert_eq!(r.pos, Vec3::new(1.0, 2.0, 3.0));
        assert_eq!(r.dim, Vec3::new(4.0, 5.0, 6.0));
    }

    #[test]
    fn test_rect3_default() {
        let r: Rect3 = Default::default();
        assert_eq!(r.pos, Vec3::ZERO);
        assert_eq!(r.dim, Vec3::ZERO);
    }

    #[test]
    fn test_rect3_from_slice() {
        let r: Rect3<(),()> = Rect3::from_array([1.0, 2.0, 3.0, 4.0, 5.0, 6.0]);
        assert_eq!(r.pos, Vec3::new(1.0, 2.0, 3.0));
        assert_eq!(r.dim, Vec3::new(4.0, 5.0, 6.0));
    }

    #[test]
    fn test_rect3_contains_point_coords() {
        let r: Rect3<(),()> = Rect3::new(Vec3::new(1.0, 1.0, 1.0), Vec3::new(3.0, 3.0, 3.0));
        // Point inside
        assert!(r.contains_point_coords(2.0, 2.0, 2.0));
        // Point on min_edge (inclusive)
        assert!(r.contains_point_coords(1.0, 1.0, 1.0));
        assert!(r.contains_point_coords(1.0, 2.5, 2.5));
        assert!(r.contains_point_coords(2.5, 1.0, 2.5));
        assert!(r.contains_point_coords(2.5, 2.5, 1.0));
        // Point on max_edge (exclusive)
        assert!(!r.contains_point_coords(4.0, 4.0, 4.0));
        assert!(!r.contains_point_coords(1.0, 1.0, 4.0));
        assert!(!r.contains_point_coords(1.0, 4.0, 1.0));
        assert!(!r.contains_point_coords(4.0, 1.0, 1.0));
        // Point outside
        assert!(!r.contains_point_coords(0.0, 0.0, 0.0));
        assert!(!r.contains_point_coords(5.0, 5.0, 5.0));

        // Test with negative dimensions (should normalize)
        let r_neg_dim: Rect3<(),()> = Rect3::new(Vec3::new(4.0, 4.0, 4.0), Vec3::new(-3.0, -3.0, -3.0));
        assert!(r_neg_dim.contains_point_coords(2.0, 2.0, 2.0));
        assert!(r_neg_dim.contains_point_coords(1.0, 1.0, 1.0)); // min edge
        assert!(!r_neg_dim.contains_point_coords(4.0, 4.0, 4.0)); // max edge
    }

    #[test]
    fn test_rect3_contains_point() {
        let r: Rect3<(),()> = Rect3::new(Vec3::new(1.0, 1.0, 1.0), Vec3::new(3.0, 3.0, 3.0));
        assert!(r.contains_point(Vec3::new(2.0, 2.0, 2.0)));
        assert!(!r.contains_point(Vec3::new(5.0, 5.0, 5.0)));
    }

    #[test]
    fn test_rect3_intersects_and_intersection() {
        let r1: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(2.0, 2.0, 2.0));
        let r2: Rect3<(),()> = Rect3::new(Vec3::new(1.0, 1.0, 1.0), Vec3::new(2.0, 2.0, 2.0));
        let r3: Rect3<(),()> = Rect3::new(Vec3::new(3.0, 3.0, 3.0), Vec3::new(1.0, 1.0, 1.0));
        let r4: Rect3<(),()> = Rect3::new(Vec3::new(0.5, 0.5, 0.5), Vec3::new(1.0, 1.0, 1.0)); // r4 is inside r1

        // Intersection r1 and r2
        assert!(r1.intersects(&r2));
        assert_eq!(
            r1.intersection(&r2),
            Some(Rect3::new(
                Vec3::new(1.0, 1.0, 1.0),
                Vec3::new(1.0, 1.0, 1.0)
            ))
        );

        // No intersection r1 and r3
        assert!(!r1.intersects(&r3));
        assert_eq!(r1.intersection(&r3), None);

        // r4 is contained in r1
        assert!(r1.intersects(&r4));
        assert_eq!(r1.intersection(&r4), Some(r4));
        assert!(r4.intersects(&r1));
        assert_eq!(r4.intersection(&r1), Some(r4));

        // Touching edges
        let r_touch_x = Rect3::new(Vec3::new(2.0, 0.0, 0.0), Vec3::new(1.0, 2.0, 2.0));
        assert!(!r1.intersects(&r_touch_x));
        assert_eq!(r1.intersection(&r_touch_x), None);

        // Rectangles with negative dimensions
        let r_neg_dim1: Rect3<(),()> = Rect3::new(Vec3::new(2.0, 2.0, 2.0), Vec3::new(-2.0, -2.0, -2.0));
        let r_neg_dim2: Rect3<(),()> = Rect3::new(Vec3::new(3.0, 3.0, 3.0), Vec3::new(-2.0, -2.0, -2.0));
        assert!(r_neg_dim1.intersects(&r_neg_dim2));
        assert_eq!(
            r_neg_dim1.intersection(&r_neg_dim2),
            Some(Rect3::new(
                Vec3::new(1.0, 1.0, 1.0),
                Vec3::new(1.0, 1.0, 1.0)
            ))
        );

        // No overlap, touching at a point
        let r5: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(1.0, 1.0, 1.0));
        let r6: Rect3<(),()> = Rect3::new(Vec3::new(1.0, 1.0, 1.0), Vec3::new(1.0, 1.0, 1.0));
        assert!(!r5.intersects(&r6));
        assert_eq!(r5.intersection(&r6), None);
    }

    #[test]
    fn test_rect3_min_max_size() {
        let r: Rect3<(),()> = Rect3::new(Vec3::new(3.0, 2.0, 5.0), Vec3::new(-2.0, 5.0, -3.0));
        assert_eq!(r.min(), Vec3::new(1.0, 2.0, 2.0));
        assert_eq!(r.max(), Vec3::new(3.0, 7.0, 5.0));
        assert_eq!(r.size(), Vec3::new(2.0, 5.0, 3.0));
    }

    #[test]
    fn test_rect3_volume() {
        let r: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(3.0, 4.0, 2.0));
        assert_eq!(r.volume(), 24.0);
        let r_neg: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(-3.0, 4.0, 2.0));
        assert_eq!(r_neg.volume(), 24.0);
    }

    #[test]
    fn test_rect3_is_empty() {
        let r: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(0.0, 4.0, 2.0));
        assert!(r.is_empty());
        let r2: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(3.0, 0.0, 2.0));
        assert!(r2.is_empty());
        let r3: Rect3<(),()> = Rect3::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(3.0, 4.0, 2.0));
        assert!(!r3.is_empty());
    }

    #[test]
    fn test_rect3_from_min_max() {
        let min: Vec3<(),()> = Vec3::new(1.0, 2.0, 3.0);
        let max: Vec3<(),()> = Vec3::new(4.0, 6.0, 7.0);
        let r: Rect3<(),()> = Rect3::from_min_max(min, max);
        assert_eq!(r.min(), min);
        assert_eq!(r.max(), max);
    }

    #[test]
    fn test_rect3_expand_to_include() {
        let r: Rect3<(),()> = Rect3::from_min_max(Vec3::new(1.0, 2.0, 3.0), Vec3::new(3.0, 4.0, 5.0));
        let expanded = r.expand_to_include(Vec3::new(5.0, 0.0, 6.0));
        assert_eq!(expanded.min(), Vec3::new(1.0, 0.0, 3.0));
        assert_eq!(expanded.max(), Vec3::new(5.0, 4.0, 6.0));
    }

    #[test]
    fn test_rect3_union() {
        let a: Rect3<(),()> = Rect3::from_min_max(Vec3::new(0.0, 0.0, 0.0), Vec3::new(2.0, 2.0, 2.0));
        let b: Rect3<(),()> = Rect3::from_min_max(Vec3::new(1.0, -1.0, 1.0), Vec3::new(3.0, 1.0, 4.0));
        let u = a.union(&b);
        assert_eq!(u.min(), Vec3::new(0.0, -1.0, 0.0));
        assert_eq!(u.max(), Vec3::new(3.0, 2.0, 4.0));
    }

    #[test]
    fn test_rect3_closest_point_and_distance() {
        let rect: Rect3<(),()> = Rect3::from_min_max(Vec3::new(1.0, 1.0, 1.0), Vec3::new(3.0, 4.0, 5.0));
        // Inside
        assert_eq!(
            rect.closest_point(Vec3::new(2.0, 2.0, 2.0)),
            Vec3::new(2.0, 2.0, 2.0)
        );
        assert_eq!(rect.distance(Vec3::new(2.0, 2.0, 2.0)), 0.0);
        // Outside
        assert_eq!(
            rect.closest_point(Vec3::new(0.0, 0.0, 0.0)),
            Vec3::new(1.0, 1.0, 1.0)
        );
        assert!((rect.distance(Vec3::new(0.0, 0.0, 0.0)) - (3.0_f32).sqrt()).abs() < 1e-6);
        assert_eq!(
            rect.closest_point(Vec3::new(4.0, 5.0, 6.0)),
            Vec3::new(3.0, 4.0, 5.0)
        );
    }

    #[test]
    fn test_rect3_intersect_ray() {
        let rect: Rect3<(),()> = Rect3::from_min_max(Vec3::new(1.0, 1.0, 1.0), Vec3::new(3.0, 4.0, 5.0));
        // Ray from outside, hits
        let t = rect.intersect_ray(Vec3::new(0.0, 2.0, 2.0), Vec3::new(1.0, 0.0, 0.0));
        assert!(t.is_some() && (t.unwrap() - 1.0).abs() < 1e-6);
        // Ray from inside
        let t2 = rect.intersect_ray(Vec3::new(2.0, 2.0, 2.0), Vec3::new(1.0, 0.0, 0.0));
        assert!(t2.is_some() && (t2.unwrap() - 1.0).abs() < 1e-6);
        // Ray misses
        let t3 = rect.intersect_ray(Vec3::new(0.0, 0.0, 0.0), Vec3::new(-1.0, 0.0, 0.0));
        assert!(t3.is_none());
    }

    #[test]
    fn test_rect3_transform() {
        use crate::mat4::Mat4;
        let rect: Rect3<(),()> = Rect3::from_min_max(Vec3::new(1.0, 2.0, 3.0), Vec3::new(3.0, 4.0, 5.0));
        let m = Mat4::from_translation(Vec3::new(10.0, 20.0, 30.0));
        let t = rect.transform(&m);
        assert_eq!(t.min(), Vec3::new(11.0, 22.0, 33.0));
        assert_eq!(t.max(), Vec3::new(13.0, 24.0, 35.0));
    }
}

// --- Compile-time (const) tests/examples for Rect3 ---
const _CONST_RECT0: Rect3f32 = Rect3f32::new(Vec3f32::new(1.0, 2.0, 3.0), Vec3f32::new(4.0, 5.0, 6.0));
const _CONST_RECT1: Rect3f32 = Rect3f32::new(Vec3f32::new(7.0, 8.0, 9.0), Vec3f32::new(10.0, 11.0, 12.0));
const _CONST_RECT_FROM_ARRAY: Rect3f32 = Rect3f32::from_array([1.0, 2.0, 3.0, 4.0, 5.0, 6.0]);
const _CONST_RECT_MIN: Vec3f32 = _CONST_RECT0.min();
const _CONST_RECT_MAX: Vec3f32 = _CONST_RECT0.max();
const _CONST_RECT_METERS: Rect3Meters = Rect3Meters::new(Vec3Meters::new(1.0, 2.0, 3.0), Vec3Meters::new(4.0, 5.0, 6.0));
const _CONST_RECT_WORLD: Rect3World = Rect3World::new(Vec3World::new(1.0, 2.0, 3.0), Vec3World::new(4.0, 5.0, 6.0));

const _: () = {
    // Compile-time assertions for const-everything
    assert!(_CONST_RECT0.pos.x == 1.0 && _CONST_RECT0.pos.y == 2.0 && _CONST_RECT0.pos.z == 3.0);
    assert!(_CONST_RECT0.dim.x == 4.0 && _CONST_RECT0.dim.y == 5.0 && _CONST_RECT0.dim.z == 6.0);
    assert!(_CONST_RECT_FROM_ARRAY.pos.x == 1.0 && _CONST_RECT_FROM_ARRAY.pos.y == 2.0 && _CONST_RECT_FROM_ARRAY.pos.z == 3.0);
    assert!(_CONST_RECT_FROM_ARRAY.dim.x == 4.0 && _CONST_RECT_FROM_ARRAY.dim.y == 5.0 && _CONST_RECT_FROM_ARRAY.dim.z == 6.0);
    assert!(_CONST_RECT_MIN.x == 1.0 && _CONST_RECT_MIN.y == 2.0 && _CONST_RECT_MIN.z == 3.0);
    assert!(_CONST_RECT_MAX.x == 5.0 && _CONST_RECT_MAX.y == 7.0 && _CONST_RECT_MAX.z == 9.0);
};

// Compile-time type safety: the following lines would fail to compile if uncommented
// const _FAIL: Rect3Meters = Rect3Pixels::new(Vec3Pixels::new(1.0, 2.0, 3.0), Vec3Pixels::new(4.0, 5.0, 6.0)); // error: mismatched types
// const _FAIL2: Rect3World = Rect3Local::new(Vec3Local::new(1.0, 2.0, 3.0), Vec3Local::new(4.0, 5.0, 6.0)); // error: mismatched types

#[test]
fn test_rect3_meters_to_pixels() {
    let meters: Rect3Meters = Rect3Meters::new(Vec3Meters::new(2.0, 3.0, 4.0), Vec3Meters::new(5.0, 6.0, 7.0));
    let pixels = meters.to_pixels(100.0);
    assert_eq!(pixels.pos, Vec3Pixels::new(200.0, 300.0, 400.0));
    assert_eq!(pixels.dim, Vec3Pixels::new(500.0, 600.0, 700.0));
}