code: public IntersectionType intersectionType (Box box) {
          // exit quickly in cases where the bounding boxes don't overlap (equivalent to a separating
          // axis test using the axes of the box)
          if (!_bounds.intersects(box)) {
              return IntersectionType.NONE;
          }
  
          // consider each side of the frustum as a potential separating axis
          int ccount = 0;
          for (int ii = 0; ii < 6; ii++) {
              // determine how many vertices fall inside/outside the plane
              int inside = 0;
              Plane plane = _planes[ii];
              for (int jj = 0; jj < 8; jj++) {
                  if (plane.distance(box.vertex(jj, _vertex)) <= 0f) {
                      inside++;
                  }
              }
              if (inside == 0) {
                  return IntersectionType.NONE;
              } else if (inside == 8) {
                  ccount++;
              }
          }
          return (ccount == 6) ? IntersectionType.CONTAINS : IntersectionType.INTERSECTS;
      }
docs: Checks whether the frustum intersects the specified box.