code: function sphereVsAabb(contactPoint, contactNormal, sphere, aabb) {
    findClosestPointFromAabbSurfaceToPoint(contactPoint, aabb, sphere.centerOfVolume);
    findAabbNormalFromContactPoint(contactNormal, contactPoint, aabb);
    vec3.negate(contactNormal, contactNormal);
  }
docs: Finds the closest point on the surface of the AABB to the sphere center.
  
  @param {vec3} contactPoint Output param.
  @param {vec3} contactNormal Output param.
  @param {Sphere} sphere
  @param {Aabb} aabb