#ifndef GFXMATH_MAT2_INCLUDED // -*- C++ -*-
#define GFXMATH_MAT2_INCLUDED

#include <gfx/math/Vec2.h>

namespace simplif
{
	class Mat2
	{
	private:
		Vec2 row[2];

	protected:

		inline void copy(const Mat2& m);
		inline Vec2 col(int i) const {return Vec2(row[0][i],row[1][i]);}

	public:
		// Standard matrices
		static Mat2 identity;
		static Mat2 zero;
		static Mat2 unit;

		// Standard constructors
		Mat2() { copy(zero); }
		Mat2(const Vec2& r0,const Vec2& r1)
		{ row[0]=r0; row[1]=r1; }
		Mat2(const Mat2& m) { copy(m); }

		// Access methods
		// M(i, j) == row i;col j
		real& operator()(int i, int j)       { return row[i][j]; }
		real  operator()(int i, int j) const { return row[i][j]; }

		// Assignment methods
		inline Mat2& operator=(const Mat2& m) { copy(m); return *this; }
		inline Mat2& operator+=(const Mat2& m);
		inline Mat2& operator-=(const Mat2& m);

		inline Mat2& operator*=(real s);
		inline Mat2& operator/=(real s);


		// Arithmetic methods
		inline Mat2 operator+(const Mat2& m) const;
		inline Mat2 operator-(const Mat2& m) const;
		inline Mat2 operator-() const;

		inline Mat2 operator*(real s) const;
		inline Mat2 operator/(real s) const;
		Mat2 operator*(const Mat2& m) const;

		inline Vec2 operator*(const Vec2& v) const; // [x y]

		// Matrix operations
		real det();
		Mat2 transpose();
		real inverse(Mat2&);


		// Input/Output methods
/*		friend ostream& operator<<(ostream&, const Mat2&);
		friend istream& operator>>(istream&, Mat2&);*/
	};


	inline void Mat2::copy(const Mat2& m)
	{
		row[0] = m.row[0]; row[1] = m.row[1];
	}

	inline Mat2& Mat2::operator+=(const Mat2& m)
	{
		row[0] += m.row[0]; row[1] += m.row[1];
		return *this;
	}

	inline Mat2& Mat2::operator-=(const Mat2& m)
	{
		row[0] -= m.row[0]; row[1] -= m.row[1];
		return *this;
	}

	inline Mat2& Mat2::operator*=(real s)
	{
		row[0] *= s; row[1] *= s;
		return *this;
	}

	inline Mat2& Mat2::operator/=(real s)
	{
		row[0] /= s; row[1] /= s;
		return *this;
	}

	inline Mat2 Mat2::operator+(const Mat2& m) const
	{
		return Mat2(row[0]+m.row[0],
			row[1]+m.row[1]);
	}

	inline Mat2 Mat2::operator-(const Mat2& m) const
	{
		return Mat2(row[0]-m.row[0],
			row[1]-m.row[1]);
	}

	inline Mat2 Mat2::operator-() const
	{
		return Mat2(-row[0], -row[1]);
	}

	inline Mat2 Mat2::operator*(real s) const
	{
		return Mat2(row[0]*s, row[1]*s);
	}

	inline Mat2 Mat2::operator/(real s) const
	{
		return Mat2(row[0]/s, row[1]/s);
	}

	inline Vec2 Mat2::operator*(const Vec2& v) const
	{
		return Vec2(row[0]*v, row[1]*v);
	}
}
/*
inline ostream& operator<<(ostream& out, const Mat2& M)
{
    return out << M.row[0] << endl  << M.row[1];
}

inline istream& operator>>(istream& in, Mat2& M)
{
    return in >> M.row[0] >> M.row[1];
}
*/

// GFXMATH_MAT2_INCLUDED
#endif