CGAL 5.4.4 - Intersecting Sequences of dD Iso-oriented Boxes

The function box_self_intersection_all_pairs_d() computes the pairwise intersecting boxes in a sequence of iso-oriented boxes in arbitrary dimension.

It does so by comparing all possible pairs of boxes and is thus inferior to the fast box_self_intersection_d() algorithm.

The sequence of boxes is given with a forward iterator range. The sequence is not modified. For each intersecting pair of boxes a callback function object is called with the two intersecting boxes as argument.

The algorithm is interface compatible with the box_self_intersection_d() function. Similarly, we call the value_type of the iterators the box handle, which is either our box type or a pointer type to our box type.

A \( d\)-dimensional iso-oriented box is defined as the Cartesian product of \( d\) intervals. We call the box half-open if the \( d\) intervals \( \{ [lo_i,hi_i) \,|\, 0 \leq i < d\}\) are half-open intervals, and we call the box closed if the \( d\) intervals \( \{ [lo_i,hi_i] \,|\, 0 \leq i < d\}\) are closed intervals. Note that closed boxes support zero-width boxes and they can intersect at their boundaries, while non-empty half-open boxes always have a positive volume and they only intersect iff their interiors overlap. The distinction between closed or half-open boxes does not require a different representation of boxes, just a different interpretation when comparing boxes, which is selected with the topology parameter and its two values, Box_intersection_d::HALF_OPEN and Box_intersection_d::CLOSED.

The algorithm uses a traits class of the BoxIntersectionTraits_d concept to access the boxes. A default traits class is provided that assumes that the box type is a model of the BoxIntersectionBox_d concept and that the box handle, i.e., the iterators value type, is identical to the box type or a pointer to the box type.


See also


The algorithm is trivially testing all pairs and runs therefore in time \( O(n^2)\) where \( n\) is the size of the input sequence. This algorithm does not use the id-number of the boxes.


template<class ForwardIter , class Callback >
void CGAL::box_self_intersection_all_pairs_d (ForwardIter begin, ForwardIter end, Callback callback, CGAL::Box_intersection_d::Topology topology=CGAL::Box_intersection_d::CLOSED)
 Invocation of box intersection with default box traits Box_intersection_d::Box_traits_d<Box_handle>, where Box_handle corresponds to the iterator value type of ForwardIter.
template<class ForwardIter , class Callback , class BoxTraits >
void CGAL::box_self_intersection_all_pairs_d (ForwardIter begin, ForwardIter end, Callback callback, BoxTraits box_traits, CGAL::Box_intersection_d::Topology topology=CGAL::Box_intersection_d::CLOSED)
 Invocation with custom box traits.