affine_transformation.hpp

#ifndef PASTELMATH_AFFINE_TRANSFORMATION_HPP
#define PASTELMATH_AFFINE_TRANSFORMATION_HPP

#include "pastel/math/affine/affine_transformation.h"

namespace Pastel
{

    template <typename Real>
    void swap(
        AffineTransformation<Real>& left,
        AffineTransformation<Real>& right)
    {
        left.swap(right);
    }

    template <typename Real>
    Matrix<Real> asMatrix(
        const AffineTransformation<Real>& that)
    {
        integer n = that.n();
        Matrix<Real> result(n + 1, n + 1);
        for (integer i = 0;i < n;++i)
        {
            result.column(i) = extend(that.matrix().column(i), 0);
        }
        result.column(n) = extend(that.translation(), 1);

        return result;
    }

    template <typename Real, integer N>
    Vector<Real, N> transformVector(
        const AffineTransformation<Real>& affine,
        const Vector<Real, N>& vector)
    {
        // Ax
        return affine.matrix() * vector;
    }

    template <typename Real, integer N>
    Vector<Real, N> transformPoint(
        const AffineTransformation<Real>& affine,
        const Vector<Real, N>& point)
    {
        // Ax + b
        return affine.matrix() * point + affine.translation();
    }

    template <typename Real, integer N>
    Vector<Real, N> transformNormal(
        const AffineTransformation<Real>& affineInverse,
        const Vector<Real, N>& normal)
    {
        // A^(-T) x
        return transpose(affineInverse.matrix()) * normal;
    }

}

#endif