def velocity(self, pnt: Vector):
r = pnt
ra = self.pnta
rb = self.pntb
a = r - ra
b = r - rb
am = a.return_magnitude()
bm = b.return_magnitude()
vel = Vector(0.0, 0.0, 0.0)
if pnt != self.pnti:
axb = a**b
if axb.return_magnitude() != 0.0:
den = am * bm + a * b
vel += axb / den * (1 / am + 1 / bm)
axx = Vector(0.0, a.z, -a.y)
if axx.return_magnitude() != 0.0:
den = am - a.x
vel += axx / den / am
bxx = Vector(0.0, b.z, -b.y)
if bxx.return_magnitude() != 0.0:
den = bm - b.x
vel -= bxx / den / bm
vel = vel / fourPi
return vel
def set_hinge_vector(self, hvec: Vector):
if hvec.return_magnitude() != 0.0:
self.uhvec = hvec.to_unit()
else:
self.uhvec = hvec
