FCL is a library for performing three types of proximity queries on a pair of
geometric models composed of triangles.

It performs:
* Collision detection: detecting whether the two models overlap, and optionally,
  all of the triangles that overlap.
* Distance computation: computing the minimum distance between a pair of models,
  i.e., the distance between the closest pair of points.
* Tolerance verification: determining whether two models are closer or farther
  than a tolerance distance.
* Continuous collision detection: detecting whether the two moving models
  overlap during the movement, and optionally, the time of contact.
* Contact information: for collision detection and continuous collision
  detection, the contact information (including contact normals and contact
  points) can be returned optionally.

WWW: https://github.com/flexible-collision-library/fcl