#include <stdint.h>
#include <math.h>
#include <vect_base.h>
-
+
/* Return scalar product */
-float
+float
vect_pscal(vect_t *v, vect_t *w)
{
return v->x * w->x + v->y * w->y;
}
/* Return Z of vectorial product */
-float
+float
vect_pvect(vect_t *v, vect_t *w)
{
return v->x*w->y - v->y*w->x;
}
/* Return scalar product */
-int8_t
+int8_t
vect_pscal_sign(vect_t *v, vect_t *w)
{
float z;
}
/* Return Z of vectorial product */
-int8_t
+int8_t
vect_pvect_sign(vect_t *v, vect_t *w)
{
float z;
return z>0?1:-1;
}
-/* float norm(float x1, float y1, float x2, float y2) */
-/* { */
-/* float x = x2 - x1; */
-/* float y = y2 - y1; */
-/* return sqrt(x*x + y*y); */
-/* } */
+float xy_norm(float x1, float y1, float x2, float y2)
+{
+ float x = x2 - x1;
+ float y = y2 - y1;
+ return sqrt(x*x + y*y);
+}
-float pt_norm(point_t *p1, point_t *p2)
+float pt_norm(const point_t *p1, const point_t *p2)
{
float x = p2->x - p1->x;
float y = p2->y - p1->y;
}
/* norm of a vector */
-float
-vect_norm(vect_t *v)
+float vect_norm(const vect_t *v)
{
return sqrt(v->x*v->x+v->y*v->y);
}
void vect_rot_trigo(vect_t *v)
{
float s;
-
+
s = v->x;
v->x= -v->y;
v->y = s;
-}
+}
void vect_rot_retro(vect_t *v)
{
float s;
-
+
s = v->x;
v->x= v->y;
v->y = -s;
-}
+}
float vect_get_angle(vect_t *v, vect_t *w)
{
float ps;
float n;
-
+
ps = vect_pscal(v, w);
n = vect_norm(v) * vect_norm(w);
-
+
return acos((float)ps/n);
}