def time_sphere_intersection():
# create a transform
o2w = translate(Vector(10,0,0)) * scale(1.3, 1.8, 2.0)
w2o = o2w.inverse()
# create the sphere
sphere = Sphere(o2w, w2o, False, 1.0, -1.0, 1.0, 360)
# create a large amount of rays,
# choose so that half of them will intersect the ray
positions = [Point(random.randint(0,100),
random.randint(0,100),
random.randint(0,100)
) for i in range(size)]
ray = Ray(Point(0,0,0), Vector(1.0, 1.0, 1.0))
vectors = []
for i in xrange(size):
position = positions[i]
if i%2 == 0:
# make sure this ray hit the sphere
vector = sphere.object_to_world(Point(0, 0, 0)) - position
vector /= float(random.randint(1,10))
else:
# construct a random vector
vector = Vector((random.random()-0.5)*random.randint(1,5),
(random.random()-0.5)*random.randint(1,5),
(random.random()-0.5*random.randint(1,5)))
vectors.append(vector)
intersections = 0
t1 = time.time()
for i in xrange(nb_calls):
ray.o = positions[i%size]
ray.d = vectors[i%size]
if sphere.intersect_p(ray):
intersections += 1
t2 = time.time()
for i in xrange(nb_calls):
ray.o = positions[i%size]
ray.d = vectors[i%size]
sphere.intersect(ray)
t3 = time.time()
print "%d calls, %d intersections" % (nb_calls, intersections)
print "Sphere.intersect_p() %.2fms" % ((t2-t1)/float(nb_calls)*1000.0)
print "Sphere.intersect() %.2fms" % ((t3-t2)/float(nb_calls)*1000.0)
def generate_ray(self, sample):
"""Generate a Ray from the camera."""
# Generate raster and camera samples
p_ras = Point(sample.image_x, sample.image_y, 0)
p_camera = self.raster_to_camera(p_ras)
ray = Ray(Point(0, 0, 0),
normalize(Vector.from_point(p_camera)),
0.0,
float('inf'))
# Modify ray for depth of field
if self.lens_radius > 0.0:
# Sample point on lens
lens_u, lens_v = concentric_sample_disk(sample.lens_u,
sample.lens_v)
lens_u *= self.lens_radius
lens_v *= self.lens_radius
# Compute point on plane of focus
ft = self.focal_distance / ray.d.z
p_focus = ray(ft)
# Update ray for effect of lens
ray.o = Point(lens_u, lens_v, 0.0)
ray.d = normalize(p_focus - ray.o)
ray.time = sample.time
ray = self.camera_to_world(ray)
return 1.0, ray
def generate_ray(self, sample):
"""Generate a Ray from the camera."""
# Generate raster and camera samples
p_ras = Point(sample.image_x, sample.image_y, 0)
p_camera = self.raster_to_camera(p_ras)
ray = Ray(Point(0, 0, 0), normalize(Vector.from_point(p_camera)), 0.0,
float('inf'))
# Modify ray for depth of field
if self.lens_radius > 0.0:
# Sample point on lens
lens_u, lens_v = concentric_sample_disk(sample.lens_u,
sample.lens_v)
lens_u *= self.lens_radius
lens_v *= self.lens_radius
# Compute point on plane of focus
ft = self.focal_distance / ray.d.z
p_focus = ray(ft)
# Update ray for effect of lens
ray.o = Point(lens_u, lens_v, 0.0)
ray.d = normalize(p_focus - ray.o)
ray.time = sample.time
ray = self.camera_to_world(ray)
return 1.0, ray
