intersect_line_alignedplane.h

// Description: Intersection between a line and an aligned plane

#ifndef PASTELGEOMETRY_INTERSECT_LINE_ALIGNEDPLANE_H
#define PASTELGEOMETRY_INTERSECT_LINE_ALIGNEDPLANE_H

#include "pastel/sys/mytypes.h"
#include "pastel/geometry/shape/line.h"
#include "pastel/geometry/shape/alignedplane.h"

namespace Pastel
{

    //! Finds the intersection between a line and an aligned plane.
    template <typename Real, int N>
    bool intersect(const Line<Real, N>& line,
        const AlignedPlane<Real, N>& alignedPlane, Real& t)
    {
        Real result(
            alignedPlane.position() - line.position()[alignedPlane.axis()]);
        Real divider(
            line.direction()[alignedPlane.axis()]);

        // EPSILON
        if (divider == 0)
        {
            // EPSILON
            if (result == 0)
            {
                t = 0;
                // Parallel, on the plane
                return true;
            }

            // Parallel, not on the plane.
            return false;
        }

        t = result / divider;

        return true;
    }

}

#endif