def hit(self, r: Ray, t_min: float, t_max: float) -> Optional[HitRecord]:
rec1 = self.boundary.hit(r, -np.inf, np.inf)
if rec1 is None:
return None
rec2 = self.boundary.hit(r, rec1.t + 0.0001, np.inf)
if rec2 is None:
return None
if rec1.t < t_min:
rec1.t = t_min
if rec1.t < 0:
rec1.t = 0
if rec2.t > t_max:
rec2.t = t_max
if rec1.t >= rec2.t:
return None
ray_length = r.direction().length()
distance_inside_boundary = (rec2.t - rec1.t) * ray_length
hit_distance = self.neg_inv_density * np.log(random_float())
if hit_distance > distance_inside_boundary:
return None
t = rec1.t + hit_distance / ray_length
p = r.at(t)
rec = HitRecord(p, t, self.phase_function)
rec.normal = Vec3(1, 0, 0)
rec.front_face = True
return rec
def hit(self, r: Ray, t_min: float, t_max: float) -> Optional[HitRecord]:
oc: Vec3 = r.origin() - self.center
a: float = r.direction().length_squared()
half_b: float = oc @ r.direction()
c: float = oc.length_squared() - self.radius**2
discriminant: float = half_b**2 - a * c
if discriminant > 0:
root: float = np.sqrt(discriminant)
t_0: float = (-half_b - root) / a
t_1: float = (-half_b + root) / a
if t_min < t_0 < t_max:
t = t_0
elif t_min < t_1 < t_max:
t = t_1
else:
return None
point: Point3 = r.at(t)
outward_normal: Vec3 = (point - self.center) / self.radius
rec = HitRecord(point, t, self.material)
rec.set_face_normal(r, outward_normal)
return rec
return None
def hit(self, r: Ray, t_min: float, t_max: float) -> Optional[HitRecord]:
t = (self.k - r.origin().x()) / r.direction().x()
if t < t_min or t > t_max:
return None
y = r.origin().y() + t*r.direction().y()
z = r.origin().z() + t*r.direction().z()
if (y < self.y0) or (y > self.y1) or (z < self.z0) or (z > self.z1):
return None
rec = HitRecord(r.at(t), t, self.material)
rec.set_face_normal(r, Vec3(1, 0, 0))
rec.u = (y - self.y0) / (self.y1 - self.y0)
rec.v = (z - self.z0) / (self.z1 - self.z0)
return rec