distance_segment_segment.h

// Description: Distance between two line segments

#ifndef PASTELGEOMETRY_DISTANCE_SEGMENT_SEGMENT_H
#define PASTELGEOMETRY_DISTANCE_SEGMENT_SEGMENT_H

#include "pastel/geometry/shape/segment.h"
#include "pastel/geometry/closest/closest_segment_segment.h"
#include "pastel/math/norm/euclidean_norm.h"

namespace Pastel
{

    //! Euclidean distance between line segments.
    /*!
   Preconditions:
   aSegment.n() == bSegment.n()

   Time complexity: O(aSegment.n())
   */
    template <typename Real, int N>
    auto distance2(
        const Segment<Real, N>& aSegment,
        const Segment<Real, N>& bSegment)
    {
        PENSURE_OP(aSegment.n(), ==, bSegment.n());
        auto norm = Euclidean_Norm<Real>();
        const Tuple<Real, 2> t = closest(aSegment, bSegment);
        return norm[dot(bSegment.at(t[1]) - aSegment.at(t[0]))];
    }

}

#endif