function float[] matrix_multiplication(vector4 mat_1[]; float mat_2[])

{

float result[];

vector4 temp_matrix[];

temp_matrix[0] = set( 0, 0, 0, 0 );

temp_matrix[1] = set( 0, 0, 0, 0 );

temp_matrix[2] = set( 0, 0, 0, 0 );

temp_matrix[3] = set( 0, 0, 0, 0 );

if (4 == len(mat_2))

{

for (int i = 0; i < len(mat_1); i++)

{

for (int j = 0; j < 1; j++)

{

float temp = 0;

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

{

temp += mat_1[i][k] * mat_2[k];

}

temp_matrix[i][j] = temp;

}

}

}

result[0] = temp_matrix[0][0];

result[1] = temp_matrix[1][0];

result[2] = temp_matrix[2][0];

result[3] = temp_matrix[3][0];

return result;

};

void DrawLine(int offset;int i;int j;vector4 final_coordinates[])

{

vector start = set(final_coordinates[i + offset][0], final_coordinates[i + offset][1], final_coordinates[i + offset][2]);

vector end = set(final_coordinates[j + offset][0], final_coordinates[j + offset][1], final_coordinates[j + offset][2]);

int a = addpoint(0,start);

int b = addpoint(0,end);

int aa = addprim(0,"polyline",a,b);

}

float rot_speed=1.0f;

float theta = 0;

float cam_dist = 3;

int side_length = 5;

vector4 final_coordinates[];

vector4 coordinates[] ={{ -1, -1, -1, 1 },{ 1, -1, -1, 1 },{ 1, 1, -1, 1 },{ -1, 1, -1, 1 },

{ -1, -1, 1, 1 },{ 1, -1, 1, 1 },{ 1, 1, 1, 1 },{ -1, 1, 1, 1 },

{ -1, -1, -1, -1 },{ 1, -1, -1, -1 },{ 1, 1, -1, -1 },{ -1, 1, -1, -1 },

{ -1, -1, 1, -1 },{ 1, -1, 1, -1 },{ 1, 1, 1, -1 },{ -1, 1, 1, -1 }};

theta += rot_speed*$F/50;

vector4 rotation_matrix[] ;

rotation_matrix[0] = set( 1, 0, 0, 0 );

rotation_matrix[1] = set( 0, 1, 0, 0 );

rotation_matrix[2] = set( 0, 0, cos(theta), -sin(theta) );

rotation_matrix[3] = set( 0, 0, sin(theta), cos(theta) );

for (int i = 0; i < 16; i++)

{

float temp_coordinate_matrix[];

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

{

temp_coordinate_matrix[k] = coordinates[i][k];

}

float rot_temp[] = matrix_multiplication(rotation_matrix, temp_coordinate_matrix);

float perspective_dist = 1 / (cam_dist - rot_temp[len(rot_temp) - 1]);

float proj_temp[];

proj_temp[0] = perspective_dist * rot_temp[0] * side_length / 2;

proj_temp[1] = perspective_dist * rot_temp[1] * side_length / 2;

proj_temp[2] = perspective_dist * rot_temp[2] * side_length / 2;

proj_temp[3] = perspective_dist * rot_temp[3] * side_length / 2;

final_coordinates[i] = set(proj_temp[0], proj_temp[1], proj_temp[2], proj_temp[3]);

}

for (int i = 0; i < 8; i++)

{

if (i < 4)

{

DrawLine(0, i, i + 4,final_coordinates);

DrawLine(0, i, i + 8,final_coordinates);

DrawLine(0, i, (i + 1) % 4,final_coordinates);

DrawLine(0, i + 4, ((i + 1) % 4) + 4,final_coordinates);

DrawLine(8, i, i + 4,final_coordinates);

DrawLine(8, i, (i + 1) % 4,final_coordinates);

DrawLine(8, i + 4, ((i + 1) % 4) + 4,final_coordinates);

}

DrawLine(0, i, i + 8,final_coordinates);

}