Enum TetrahedronPointLocation

pub enum TetrahedronPointLocation {
    OnVertex(u32),
    OnEdge(u32, [f32; 2]),
    OnFace(u32, [f32; 3]),
    OnSolid,
}

Logical description of the location of a point on a tetrahedron.

This enum describes where a point is located relative to a tetrahedron’s features (vertices, edges, faces, or interior). It’s commonly used in collision detection and geometric queries to understand spatial relationships.

Variants

• OnVertex: Point is at one of the four vertices (0=a, 1=b, 2=c, 3=d)
• OnEdge: Point lies on one of the six edges with barycentric coordinates
• OnFace: Point lies on one of the four triangular faces with barycentric coordinates
• OnSolid: Point is inside the tetrahedron volume

Examples

use parry3d::shape::{Tetrahedron, TetrahedronPointLocation};
use parry3d::math::Point;

let tetra = Tetrahedron::new(
    Point::new(0.0, 0.0, 0.0),
    Point::new(1.0, 0.0, 0.0),
    Point::new(0.0, 1.0, 0.0),
    Point::new(0.0, 0.0, 1.0),
);

// Check location of vertex
let location = TetrahedronPointLocation::OnVertex(0);
if let Some(bcoords) = location.barycentric_coordinates() {
    println!("Barycentric coordinates: {:?}", bcoords);
    // For vertex 0, this will be [1.0, 0.0, 0.0, 0.0]
}

Variants

OnVertex(u32)

The point lies on a vertex.

The vertex index maps to: 0=a, 1=b, 2=c, 3=d

OnEdge(u32, [f32; 2])

The point lies on an edge.

Contains the edge index and barycentric coordinates [u, v] where:

• u is the weight of the first vertex
• v is the weight of the second vertex
• u + v = 1.0

Edge indices:

• 0: segment AB
• 1: segment AC
• 2: segment AD
• 3: segment BC
• 4: segment BD
• 5: segment CD

OnFace(u32, [f32; 3])

The point lies on a triangular face interior.

Contains the face index and barycentric coordinates [u, v, w] where:

• u, v, w are the weights of the three vertices
• u + v + w = 1.0

Face indices:

• 0: triangle ABC
• 1: triangle ABD
• 2: triangle ACD
• 3: triangle BCD

OnSolid

The point lies inside of the tetrahedron.

Implementations

impl TetrahedronPointLocation

pub fn barycentric_coordinates(&self) -> Option<[f32; 4]>

The barycentric coordinates corresponding to this point location.

Barycentric coordinates represent a point as a weighted combination of the tetrahedron’s four vertices. The returned array [wa, wb, wc, wd] contains weights such that: point = wa*a + wb*b + wc*c + wd*d where wa + wb + wc + wd = 1.0.

Returns

• Some([wa, wb, wc, wd]): The barycentric coordinates for points on features
• None: If the location is OnSolid (point is in the interior)

Examples

use parry3d::shape::TetrahedronPointLocation;

// A point on vertex 0 (vertex a)
let location = TetrahedronPointLocation::OnVertex(0);
let bcoords = location.barycentric_coordinates().unwrap();
assert_eq!(bcoords, [1.0, 0.0, 0.0, 0.0]);

// A point on edge 0 (segment AB) at midpoint
let location = TetrahedronPointLocation::OnEdge(0, [0.5, 0.5]);
let bcoords = location.barycentric_coordinates().unwrap();
assert_eq!(bcoords, [0.5, 0.5, 0.0, 0.0]);

// A point inside the tetrahedron
let location = TetrahedronPointLocation::OnSolid;
assert!(location.barycentric_coordinates().is_none());

pub fn same_feature_as(&self, other: &TetrahedronPointLocation) -> bool

Returns true if both self and other correspond to points on the same feature of a tetrahedron.

Two point locations are considered to be on the same feature if they’re both:

• On the same vertex (same vertex index)
• On the same edge (same edge index)
• On the same face (same face index)
• Both inside the tetrahedron (OnSolid)

This is useful for determining if two points share a common geometric feature, which is important in collision detection and contact point generation.

Examples

use parry3d::shape::TetrahedronPointLocation;

let loc1 = TetrahedronPointLocation::OnVertex(0);
let loc2 = TetrahedronPointLocation::OnVertex(0);
let loc3 = TetrahedronPointLocation::OnVertex(1);

assert!(loc1.same_feature_as(&loc2));  // Same vertex
assert!(!loc1.same_feature_as(&loc3)); // Different vertices

let edge1 = TetrahedronPointLocation::OnEdge(0, [0.5, 0.5]);
let edge2 = TetrahedronPointLocation::OnEdge(0, [0.3, 0.7]);
let edge3 = TetrahedronPointLocation::OnEdge(1, [0.5, 0.5]);

assert!(edge1.same_feature_as(&edge2));  // Same edge, different coords
assert!(!edge1.same_feature_as(&edge3)); // Different edges

Trait Implementations

impl Clone for TetrahedronPointLocation

fn clone(&self) -> TetrahedronPointLocation

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TetrahedronPointLocation

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for TetrahedronPointLocation