{

float d[3]; //x,y,z coordinates

#define foreachcoord_i for(int i=0;i<3;i++)

Vector3d () {

foreachcoord_i d[i] = 0;

}

Vector3d (Point3d * p) {

d[0] = p->x;

d[1] = p->y;

d[2] = p->z;

}

Vector3d (float x, float y, float z) {

d[0] = x;

d[1] = y;

d[2] = z;

}

//wektor ab

Vector3d (Point3d * a, Point3d * b) {

d[0] = b->x - a->x;

d[1] = b->y - a->y;

d[2] = b->z - a->z;

}

void add (Vector3d * v) {

foreachcoord_i d[i] += v->d[i];

}

void sub (Vector3d * v) {

foreachcoord_i d[i] -= v->d[i];

}

void mul (float s) {

foreachcoord_i d[i] *= s;

}

float length () {

return sqrt (d[0] * d[0] + d[1] * d[1] + d[2] * d[2]);

}

void normalize () {

float old_length = length();

foreachcoord_i d[i] /= old_length;

}

void print () {

g_print ("v %f %f %f\n", d[0], d[1], d[2]);

}

Vector3d * crossProduct(Vector3d * a)

{

return new Vector3d(this->d[1]*a->d[2] - this->d[2]*a->d[1],

- this->d[0]*a->d[2] + this->d[2]*a->d[0],

this->d[0]*a->d[1] - this->d[1]*a->d[0]);

}

float dotProduct(Vector3d * a)

{

return this->d[0]*a->d[0] + this->d[1]*a->d[1] + this->d[2]*a->d[2];

}

#undef foreachcoord_i