def intersect(self, ray):
"""The ray t value of the first intersection point of the
ray with self, or None if no intersection occurs"""
hit = None
q = self.centre - ray.start
vDotQ = dot(ray.dir, q)
squareDiffs = dot(q, q) - self.radius*self.radius
discrim = vDotQ * vDotQ - squareDiffs
if discrim >= 0:
root = sqrt(discrim)
t0 = (vDotQ - root)
t1 = (vDotQ + root)
if t0 < t1:
hit = Hit(self, ray, t0, t1, None, self.material)
else:
hit = Hit(self, ray, t1, t0, None, self.material)
if hit.entry > 0:
hit.normal = self.normal(ray.pos(hit.entry))
if hit.exit > 0:
hit.normal2 = self.normal(ray.pos(hit.exit))
return hit
def intersect(self, ray):
"""The ray t value of the first intersection point of the
ray with self, or None if no intersection occurs"""
hit = None
q = self.centre - ray.start
vDotQ = dot(ray.dir, q)
squareDiffs = dot(q, q) - self.radius * self.radius
discrim = vDotQ * vDotQ - squareDiffs
if discrim >= 0:
root = sqrt(discrim)
t0 = (vDotQ - root)
t1 = (vDotQ + root)
if t0 < t1:
hit = Hit(self, ray, t0, t1, None, self.material)
else:
hit = Hit(self, ray, t1, t0, None, self.material)
if hit.entry > 0:
hit.normal = self.normal(ray.pos(hit.entry))
if hit.exit > 0:
hit.normal2 = self.normal(ray.pos(hit.exit))
return hit
