#ifndef VECTOR_H
#define VECTOR_H


/* instead of doing 2 v3_mag, save sqrt ops
	return -1 if 1>2, 0 eq, 1 if 2>1
*/
int v3_v1Compv2(double v1[3], double v2[3]);


double v3_sin_bw2v( double v1[3], double v2[3]);

double v3_cos_bw2v(double v1[3], double v2[3]);

double v3_magnitude(double v[3]);

void v3_assign(double vTo[3], double vFrom[3]);
void v3_assign(double vTo[3], double x, double y, double z);
double *v3_assign(double vFrom[3]);

void v3_crossp(double v1[3], double v2[3], double vres[3]);
double *v3_crossp(double v1[3], double v2[3]);

void v3_dotp(double v1[3], double v2[3], double &a);
double v3_dotp(double v1[3], double v2[3]);

/* vect vprod[3] = v[3] * s */
void v3_scale(double v[3], double s, double vprod[3]);
double *v3_scale(double v[3], double s);

void v3_add(double v1[3], double v2[3], double vres[3]);
double *v3_add(double v1[3], double v2[3]);

void v3_sub(double v1[3], double v2[3], double vres[3]);
double *v3_sub(double v1[3], double v2[3]);

/* in case of tiny mag, make the vect 0 */
void v3_normalize(double v[3], double v_unit[3]);
double *v3_normalize(double v[3]);

// for 4-d vectors
void v4_scale(double v[4], double s, double vprod[4]);

void v4_add(double v1[4], double v2[4], double vres[4]);

void v4_sub(double v1[4], double v2[4], double vres[4]);

void v4_assign(double vTo[4], double vFrom[4]);
void v4_assign(double vTo[3], double x, double y, double z, double w);

void v4_set(double vTo[4], double c);	// set vect to a const

void v4_normalize(double v[4], double v_unit[4]); /* in case of tiny mag, make the vect 0 */

// vector v2 = glmat * v1, glmat is a col major mat
void glmat44_mult_vec41(double *mat, double *v1, double *v2);

// vector v2 = mat * v1, mat is regular row major
void mat44_mult_vec41(double *mat, double *v1, double *v2);

#endif