oxihuman-mesh 0.2.1

Mesh processing, topology, and geometry algorithms for OxiHuman
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

//! Point set operations on mesh vertices.
#![allow(dead_code)]

/// A point set for spatial queries.
#[allow(dead_code)]
pub struct PointSet {
    pub points: Vec<[f32; 3]>,
}

/// Create a new, empty point set.
#[allow(dead_code)]
pub fn new_point_set() -> PointSet {
    PointSet { points: Vec::new() }
}

/// Add a point to the set.
#[allow(dead_code)]
pub fn add_point(set: &mut PointSet, p: [f32; 3]) {
    set.points.push(p);
}

/// Find the nearest point to a query point. Returns its index.
#[allow(dead_code)]
pub fn nearest_point(set: &PointSet, q: [f32; 3]) -> Option<usize> {
    if set.points.is_empty() { return None; }
    let mut best = 0;
    let mut best_dist = f32::MAX;
    for (i, &p) in set.points.iter().enumerate() {
        let dx = p[0]-q[0]; let dy = p[1]-q[1]; let dz = p[2]-q[2];
        let d = dx*dx + dy*dy + dz*dz;
        if d < best_dist { best_dist = d; best = i; }
    }
    Some(best)
}

/// Return the number of points in the set.
#[allow(dead_code)]
pub fn point_count(set: &PointSet) -> usize {
    set.points.len()
}

/// Compute the centroid of all points.
#[allow(dead_code)]
pub fn centroid(set: &PointSet) -> [f32; 3] {
    let n = set.points.len();
    if n == 0 { return [0.0; 3]; }
    let sum = set.points.iter().fold([0.0f32;3], |acc, p| [acc[0]+p[0], acc[1]+p[1], acc[2]+p[2]]);
    [sum[0]/n as f32, sum[1]/n as f32, sum[2]/n as f32]
}

/// Find all points within `radius` of query point `q`.
#[allow(dead_code)]
pub fn points_in_radius(set: &PointSet, q: [f32; 3], radius: f32) -> Vec<usize> {
    let r2 = radius * radius;
    set.points.iter().enumerate().filter_map(|(i, &p)| {
        let dx = p[0]-q[0]; let dy = p[1]-q[1]; let dz = p[2]-q[2];
        if dx*dx+dy*dy+dz*dz <= r2 { Some(i) } else { None }
    }).collect()
}

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

    fn sample_set() -> PointSet {
        let mut s = new_point_set();
        add_point(&mut s, [0.0, 0.0, 0.0]);
        add_point(&mut s, [1.0, 0.0, 0.0]);
        add_point(&mut s, [0.0, 1.0, 0.0]);
        s
    }

    #[test]
    fn test_new_point_set_empty() {
        let s = new_point_set();
        assert_eq!(point_count(&s), 0);
    }

    #[test]
    fn test_add_point() {
        let mut s = new_point_set();
        add_point(&mut s, [1.0, 2.0, 3.0]);
        assert_eq!(point_count(&s), 1);
    }

    #[test]
    fn test_nearest_point_empty() {
        let s = new_point_set();
        assert!(nearest_point(&s, [0.0,0.0,0.0]).is_none());
    }

    #[test]
    fn test_nearest_point() {
        let s = sample_set();
        let idx = nearest_point(&s, [0.9, 0.0, 0.0]).expect("should succeed");
        assert_eq!(idx, 1);
    }

    #[test]
    fn test_nearest_point_origin() {
        let s = sample_set();
        let idx = nearest_point(&s, [0.0,0.0,0.0]).expect("should succeed");
        assert_eq!(idx, 0);
    }

    #[test]
    fn test_centroid() {
        let s = sample_set();
        let c = centroid(&s);
        assert!((c[0] - 1.0/3.0).abs() < 1e-5);
    }

    #[test]
    fn test_centroid_empty() {
        let s = new_point_set();
        let c = centroid(&s);
        assert!((c[0]).abs() < 1e-5);
    }

    #[test]
    fn test_points_in_radius() {
        let s = sample_set();
        let r = points_in_radius(&s, [0.0,0.0,0.0], 0.5);
        assert!(r.contains(&0));
        assert!(!r.contains(&1));
    }

    #[test]
    fn test_points_in_radius_all() {
        let s = sample_set();
        let r = points_in_radius(&s, [0.0,0.0,0.0], 10.0);
        assert_eq!(r.len(), 3);
    }
}