/*

 * C++ RayTracer

 * file: matrix.h

 *

 * Radek Brich, 2006

 */

/* not used at this time */

#ifndef MATRIX_H

#define MATRIX_H

#include "vector.h"

using namespace std;

class Matrix

{

public:

	float data[4][4];

	Matrix(): {};

	// sum

	friend Matrix operator+(const Matrix &a, const Matrix &b)

	{

		Matrix m = Matrix();

		for (int i = 0; i < 4; i++)

			for (int j = 0; j < 4; j++)

				m.data[i][j] = a.data[i][j] + b.data[i][j];

		return m;

	}

	// difference

	friend Matrix operator-(const Matrix &a, const Matrix &b)

	{

		Matrix m = Matrix();

		for (int i = 0; i < 4; i++)

			for (int j = 0; j < 4; j++)

				m.data[i][j] = a.data[i][j] - b.data[i][j];

		return m;

	}

	// product

	friend Matrix operator*(const Matrix &a, const Matrix &b)

	{

		Matrix m = Matrix();

		for (int i = 0; i < 4; i++)

			for (int j = 0; j < 4; j++)

				m.data[i][j] =

					a.data[i][0] * b.data[0][j] +

					a.data[i][1] * b.data[1][j] +

					a.data[i][2] * b.data[2][j] +

					a.data[i][3] * b.data[3][j];

		return m;

	}

	// negative

	Matrix operator-()

	{

		Matrix m = Matrix();

		for (int i = 0; i < 4; i++)

			for (int j = 0; j < 4; j++)

				m.data[i][j] = -data[i][j];

		return m;

	}

	// product of matrix and scalar

	Matrix operator*(const float &f)

	{

		Matrix m = Matrix();

		for (int i = 0; i < 4; i++)

			for (int j = 0; j < 4; j++)

				m.data[i][j] = data[i][j] * f;

		return m;

	}

	friend Matrix operator*(const float &f, Matrix &m) { return m * f; };

	// product of matrix and vector

	Vector3 operator*(const Vector3 &v)

	{

		Vector3 u = Vector3();

		u.x = data[0][0] * v.x + data[0][1] * v.y + data[0][2] * v.z + data[0][3] * v.w;

		u.y = data[1][0] * v.x + data[1][1] * v.y + data[1][2] * v.z + data[1][3] * v.w;

		u.z = data[2][0] * v.x + data[2][1] * v.y + data[2][2] * v.z + data[2][3] * v.w;

		u.w = data[3][0] * v.x + data[3][1] * v.y + data[3][2] * v.z + data[3][3] * v.w;

		return u;

	}

	friend Matrix operator*(const Vector3 &v, Matrix &m) { return m * v; };

};

#endif