#ifndef GFXMATH_MAT4_INCLUDED // -*- C++ -*-
#define GFXMATH_MAT4_INCLUDED

/************************************************************************

  4x4 Matrix class

  $Id: Mat4.h,v 1.14 1997/06/18 15:55:22 garland Exp $

 ************************************************************************/

#include <gfx/math/Vec3.h>
#include <gfx/math/Vec4.h>

namespace simplif
{
	class Mat4
	{
	private:
		Vec4 row[4];

	protected:

		inline void copy(const Mat4& m);
		inline Vec4 col(int i) const
			{ return Vec4(row[0][i],row[1][i],row[2][i],row[3][i]); }

	public:
		// Standard matrices
		static Mat4 identity;
		static Mat4 zero;
		static Mat4 unit;

		static Mat4 trans(real,real,real);
		static Mat4 scale(real,real,real);
		static Mat4 xrot(real); //
		static Mat4 yrot(real); // Arguments are in radians
		static Mat4 zrot(real); //


		// Standard constructors
		Mat4() { copy(zero); }
		Mat4(const Vec4& r0,const Vec4& r1,const Vec4& r2,const Vec4& r3)
		{ row[0]=r0; row[1]=r1; row[2]=r2; row[3]=r3; }
		Mat4(const Mat4& 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]; }
		const Vec4& operator[](int i) const { return row[i]; }

		// Comparison methods
		inline int operator==(const Mat4&);

		// Assignment methods
		inline Mat4& operator=(const Mat4& m) { copy(m); return *this; }
		inline Mat4& operator+=(const Mat4& m);
		inline Mat4& operator-=(const Mat4& m);

		inline Mat4& operator*=(real s);
		inline Mat4& operator/=(real s);


		// Arithmetic methods
		inline Mat4 operator+(const Mat4& m) const;
		inline Mat4 operator-(const Mat4& m) const;
		inline Mat4 operator-() const;

		inline Mat4 operator*(real s) const;
		inline Mat4 operator/(real s) const;
		Mat4 operator*(const Mat4& m) const;

		inline Vec4 operator*(const Vec4& v) const; // [x y z w]
		inline Vec3 operator*(const Vec3& v) const; // [x y z w]

		// Matrix operations
		real det() const;
		Mat4 transpose() const;
		Mat4 adjoint() const;
		real inverse(Mat4&) const;
		real cramerInverse(Mat4&) const;

		// Input/Output methods
//		friend ostream& operator<<(ostream&, const Mat4&);
//		friend istream& operator>>(istream&, Mat4&);
	};


	inline void Mat4::copy(const Mat4& m)
	{
		row[0] = m.row[0]; row[1] = m.row[1];
		row[2] = m.row[2]; row[3] = m.row[3];
	}

	inline int Mat4::operator==(const Mat4& m)
	{
		return row[0]==m.row[0] &&
		   row[1]==m.row[1] &&
		   row[2]==m.row[2] &&
		   row[3]==m.row[3] ;
	}

	inline Mat4& Mat4::operator+=(const Mat4& m)
	{
		row[0] += m.row[0]; row[1] += m.row[1];
		row[2] += m.row[2]; row[3] += m.row[3];
		return *this;
	}

	inline Mat4& Mat4::operator-=(const Mat4& m)
	{
		row[0] -= m.row[0]; row[1] -= m.row[1];
		row[2] -= m.row[2]; row[3] -= m.row[3];
		return *this;
	}

	inline Mat4& Mat4::operator*=(real s)
	{
		row[0] *= s; row[1] *= s; row[2] *= s; row[3] *= s;
		return *this;
	}

	inline Mat4& Mat4::operator/=(real s)
	{
		row[0] /= s; row[1] /= s; row[2] /= s; row[3] /= s;
		return *this;
	}

	inline Mat4 Mat4::operator+(const Mat4& m) const
	{
		return Mat4(row[0]+m.row[0],
			row[1]+m.row[1],
			row[2]+m.row[2],
			row[3]+m.row[3]);
	}

	inline Mat4 Mat4::operator-(const Mat4& m) const
	{
		return Mat4(row[0]-m.row[0],
			row[1]-m.row[1],
			row[2]-m.row[2],
			row[3]-m.row[3]);
	}

	inline Mat4 Mat4::operator-() const
	{
		return Mat4(-row[0], -row[1], -row[2], -row[3]);
	}

	inline Mat4 Mat4::operator*(real s) const
	{
		return Mat4(row[0]*s, row[1]*s, row[2]*s, row[3]*s);
	}

	inline Mat4 Mat4::operator/(real s) const
	{
		return Mat4(row[0]/s, row[1]/s, row[2]/s, row[3]/s);
	}

	inline Vec4 Mat4::operator*(const Vec4& v) const
	{
		return Vec4(row[0]*v, row[1]*v, row[2]*v, row[3]*v);
	}

	//
	// Transform a homogeneous 3-vector and reproject into normal 3-space
	//
	inline Vec3 Mat4::operator*(const Vec3& v) const
	{
		Vec4 u=Vec4(v,1);
		real w=row[3]*u;

		if(w==0.0)
		return Vec3(row[0]*u, row[1]*u, row[2]*u);
		else
		return Vec3(row[0]*u/w, row[1]*u/w, row[2]*u/w);
	}

/*	inline ostream& operator<<(ostream& out, const Mat4& M)
	{
		return out<<M.row[0]<<endl<<M.row[1]<<endl<<M.row[2]<<endl<<M.row[3];
	}

	inline istream& operator>>(istream& in, Mat4& M)
	{
		return in >> M.row[0] >> M.row[1] >> M.row[2] >> M.row[3];
	}
*/
	extern bool cholesky(Mat4&, Vec4&);
	extern bool jacobi(const Mat4& m, Vec4& vals, Vec4 vecs[4]);
}

// GFXMATH_MAT4_INCLUDED
#endif