distance_point_point.h

// Description: Distance between two points

#ifndef PASTELGEOMETRY_DISTANCE_POINT_POINT_H
#define PASTELGEOMETRY_DISTANCE_POINT_POINT_H

#include "pastel/math/norm/norm_concept.h"
#include "pastel/sys/point/point_concept.h"

// Template defaults

#include "pastel/math/norm/euclidean_norm.h"
#include "pastel/sys/indicator/all_indicator.h"

namespace Pastel
{

    //! Computes the distance between points.
    template <
        Point_Concept A_Point,
        Point_Concept B_Point, 
        typename Real = Point_Real<A_Point, B_Point>,
        typename... ArgumentSet
    >
    auto distance2(
        const A_Point& aPoint,
        const B_Point& bPoint,
        ArgumentSet&&... argumentSet)
    {
        auto&& norm = 
            PASTEL_ARG_C(norm, Euclidean_Norm<Real>(), Norm_Concept);

        auto distance = norm();
        using Distance = decltype(distance);

        auto&& keepGoing = PASTEL_ARG_C1(keepGoing, allIndicator(), Indicator_Concept, Distance);

        PENSURE_OP(dimension(aPoint), ==, dimension(bPoint));

        integer n = dimension(aPoint);
        for (integer i = 0;i < n && keepGoing(distance);++i)
        {
            distance.set(i, pointAxis(bPoint, i) - pointAxis(aPoint, i));
        }

        return distance;
    }

}

#endif