1 /*

     2  * C++ RayTracer

     3  * file: matrix.h

     4  *

     5  * Radek Brich, 2006

     6  */

     7 

     8 /* not used at this time */

     9 

    10 #ifndef MATRIX_H

    11 #define MATRIX_H

    12 

    13 #include "vector.h"

    14 

    15 using namespace std;

    16 

    17 class Matrix

    18 {

    19 public:

    20 	float data[4][4];

    21 

    22 	Matrix(): {};

    23 

    24 	// sum

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

    26 	{

    27 		Matrix m = Matrix();

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

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

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

    31 		return m;

    32 	}

    33 

    34 	// difference

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

    36 	{

    37 		Matrix m = Matrix();

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

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

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

    41 		return m;

    42 	}

    43 

    44 	// product

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

    46 	{

    47 		Matrix m = Matrix();

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

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

    50 				m.data[i][j] =

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

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

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

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

    55 		return m;

    56 	}

    57 

    58 	// negative

    59 	Matrix operator-()

    60 	{

    61 		Matrix m = Matrix();

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

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

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

    65 		return m;

    66 	}

    67 

    68 	// product of matrix and scalar

    69 	Matrix operator*(const float &f)

    70 	{

    71 		Matrix m = Matrix();

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

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

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

    75 		return m;

    76 	}

    77 

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

    79 

    80 	// product of matrix and vector

    81 	Vector3 operator*(const Vector3 &v)

    82 	{

    83 		Vector3 u = Vector3();

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

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

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

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

    88 		return u;

    89 	}

    90 

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

    92 };

    93 

    94 #endif