Module manifold 

Contact manifold generation for convex primitive pairs and mesh narrow phase.

Port of box3d-cpp-reference/src/convex_manifold.c (sphere / capsule / hull pairs), triangle_manifold.c, plus the clip/edge helpers from manifold.h / manifold.c. Mesh contact assembly lives in contact/mesh_contact.rs.

SPDX-FileCopyrightText: 2025 Erin Catto SPDX-License-Identifier: MIT

Structs

FeaturePair

Contact points are always the result of two edges intersecting. It can be two edges of the same shape, which is just a shape vertex. Or a contact point can be the result of two edges crossing from different shapes. (b3FeaturePair)

LocalManifold

A local manifold with no dynamic information. Used by collide functions.

LocalManifoldPoint

A local manifold point and normal in frame A. (b3LocalManifoldPoint)

Manifold

A contact manifold describes the contact points between colliding shapes. (b3Manifold)

ManifoldPoint

A manifold point is a contact point belonging to a contact manifold. Box3D uses speculative collision so some contact points may be separated. (b3ManifoldPoint)

SatCache

Separating axis test cache. Provides temporal acceleration of collision routines. (b3SATCache)

Enums

FeatureOwner

Which shape owns a clipped feature edge. (b3FeatureOwner)

SeparatingFeature

Cached separating axis feature. (b3SeparatingFeature)

TriangleFeature

Cached triangle feature for mesh/height-field contacts. (b3TriangleFeature)

Constants

FEATURE_PAIR_SINGLE

For single point contact, such as sphere-sphere, sphere-capsule, sphere-triangle. (b3FeaturePair_single)

Functions

collide_capsule_and_sphere

Collide a capsule and a sphere. (b3CollideCapsuleAndSphere)

collide_capsule_and_triangle

Collide a capsule and a triangle. (b3CollideCapsuleAndTriangle)

collide_capsules

Collide two capsules. (b3CollideCapsules)

collide_hull_and_capsule

Collide a hull and a capsule. (b3CollideHullAndCapsule)

collide_hull_and_sphere

Collide a hull and a sphere. (b3CollideHullAndSphere)

collide_hull_and_triangle

Collide a hull and a triangle in the local space of the hull. (b3CollideHullAndTriangle)

collide_hulls

Collide two convex hulls. (b3CollideHulls)

collide_sphere_and_triangle

Collide a sphere and a triangle. (b3CollideSphereAndTriangle)

collide_spheres

Collide two spheres. (b3CollideSpheres)

edge_edge_separation

Edge-edge separation along the common normal. (b3EdgeEdgeSeparation)

find_incident_face

Find the incident face given a reference normal and closest vertex. (b3FindIncidentFace)

flip_pair

Flip a feature pair so face-A / face-B reference choice does not change ids. (b3FlipPair)

make_feature_id

Pack a feature pair into a 32-bit id. (b3MakeFeatureId)

make_feature_pair

Build a feature pair. (b3MakeFeaturePair)