def random_in_unit_disk(self):
while True:
p = Vec3(random.random(), random.random(), 0) * 2.0 - Vec3(1, 1, 0)
if (p.dot(p) < 1.0):
break
return p
def readObj(self, path):
with open(path, "rt") as file:
for line in file:
if line.startswith("v "):
info = line.split()
self.vertices.append(Vec3(float(info[1]), float(info[2]), float(info[3])))
elif line.startswith("vt "):
info = line.split()
self.tex_coords.append(Vec3(float(info[1]), float(info[2]), 0.0))
self.has_tex_coords = True
elif line.startswith("vn "):
info = line.split()
self.normals.append(Vec3(float(info[1]), float(info[2]), float(info[3])))
self.has_normals = True
elif line.startswith("f "):
info = line.split()
indices_of_vertices_of_face = []
for i in info:
if i != "f":
vertex_data = []
for j in i.split("/"):
if j == '':
vertex_data.append('')
else:
vertex_data.append(int(j) - 1)
indices_of_vertices_of_face.append(vertex_data)
self.faces.append(indices_of_vertices_of_face)
elif line.startswith("o"):
info = line.split()
self.name = info[1]
else:
continue
def color(r, world, depth):
"""Get colour for:
r ray of interest
world set of hitable objects
depth max interaction count
Returns colour as Vec3.
"""
rec = Hit_Record()
if world.hit(r, 0.001, MAXFLOAT, rec):
#
print('rec=%s' % str(rec))
sys.stdout.flush()
#
scattered = Ray()
attenuation = Vec3()
if depth < 50.0 and rec.mat_ptr.scatter(r, rec, attenuation,
scattered):
print('depth=%s' % str(depth))
return attenuation * color(scattered, world, depth + 1)
return Vec3(0, 0, 0)
else:
unit_direction = r.direction.unit_vector
t = 0.5 * (unit_direction.y + 1.0)
return Vec3(1, 1, 1) * (1.0 - t) + Vec3(0.5, 0.7, 1.0) * t
def main():
with open("output2.ppm", "w") as f:
nx, ny, ns = 200, 100, 100
header = "P3\n{} {}\n255\n".format(nx, ny)
f.write(header)
sphere1 = Sphere(Vec3(0, 0, -1), 0.5)
sphere2 = Sphere(Vec3(0, -100.5, -1), 100)
world = Hitable_list([sphere1, sphere2])
for j in range(ny - 1, -1, -1):
for i in range(0, nx):
col = Vec3(0, 0, 0)
for s in range(ns):
u = float(i + random()) / float(nx)
v = float(j + random()) / float(ny)
ray = Camera().get_ray(u, v)
col += color(ray, world)
col /= ns
col = Vec3(sqrt(col.r()), sqrt(col.g()), sqrt(col.b()))
ir = int(255.99 * col.r())
ig = int(255.99 * col.g())
ib = int(255.99 * col.b())
line = "{} {} {}\n".format(ir, ig, ib)
f.write(line)
def cornell_smoke():
'''Generate a scene with a Cornell box where the boxes are filled with smoke'''
world = HittableList()
red = Lambertian(Color(0.65, 0.05, 0.05))
white = Lambertian(Color(0.73, 0.73, 0.73))
green = Lambertian(Color(0.12, 0.45, 0.15))
light = DiffuseLight(Color(7, 7, 7))
box1 = Box(Point3(0, 0, 0), Point3(165, 330, 165), white)
box1 = RotateY(box1, 15)
box1 = Translate(box1, Vec3(265, 0, 295))
box2 = Box(Point3(0, 0, 0), Point3(165, 165, 165), white)
box2 = RotateY(box2, -18)
box2 = Translate(box2, Vec3(130, 0, 65))
world.add(yzRect(0, 555, 0, 555, 555, green))
world.add(yzRect(0, 555, 0, 555, 0, red))
world.add(xzRect(0, 555, 0, 555, 555, white))
world.add(xzRect(0, 555, 0, 555, 0, white))
world.add(xyRect(0, 555, 0, 555, 555, white))
world.add(ConstantMedium(box1, 0.01, Color(0, 0, 0)))
world.add(ConstantMedium(box2, 0.01, Color(1, 1, 1)))
world.add(xzRect(113, 443, 127, 432, 554, light))
return world
def blue_to_white(i, j, nx, ny):
r = origin_to_pixel(i, j, nx, ny)
v = r.direction().unit_vector(
) # use y-coordinate of unit direction to scale blueness
t = (v.y() + 1) / 2 # ranges between 0 and 1
return Vec3(255.99, 255.99, 255.99) * (1 - t) + Vec3(
255.99 * 0.5, 255.99 * 0.7, 255.99) * t
def diffuse_sphere(i, j, nx, ny, num_samples=100):
s1 = Sphere(Vec3(-0.75, 0.75, -1), 0.5, Lambertian(Vec3(0.8, 0.3, 0.3)))
s2 = Sphere(Vec3(0, -100.5, -1), 100, Lambertian(Vec3(0.2, 0.6, 0.2)))
spheres = HitableList([s1, s2])
cam = Camera()
def color(r, world):
if world.hit(r, 0.001, float("inf")):
scattered, attenuation = world.matrl.scatter(
r, world.p, world.normal)
if scattered:
return color(scattered, world) * attenuation
else:
return Vec3(0, 0, 0)
else:
v = r.direction().unit_vector(
) # use y-coordinate of unit direction to scale blueness
t = (v.y() + 1) / 2 # ranges between 0 and 1
return Vec3(255.99, 255.99, 255.99) * (1 - t) + Vec3(
255.99 * 0.5, 255.99 * 0.7, 255.99) * t
col = Vec3(0, 0, 0)
for k in range(num_samples):
col += color(
cam.get_ray((i + random.random()) / nx,
(j + random.random()) / ny), spheres)
return col / num_samples
def test_finte():
q1 = Quat(10000000000, 210000000000, 310000000000, -2147483647)
q2 = Quat(np.nan, 210000000000, 310000000000, -2147483647)
q3 = Quat(np.inf, 210000000000, 310000000000, -2147483647)
q4 = Quat(0.0, 210000000000, np.NINF, -2147483647)
v1 = Vec3(10000000000, 210000000000, 310000000000)
v2 = Vec3(np.nan, 210000000000, 310000000000)
v3 = Vec3(np.inf, 210000000000, 310000000000)
v4 = Vec3(0.0, 210000000000, np.NINF)
t1 = Transform(q1, v1)
assert t1.is_finite()
assert not t1.is_nan()
t2 = Transform(q1, v2)
assert not t2.is_finite()
assert t2.is_nan()
t3 = Transform(q3, v1)
assert not t3.is_finite()
assert t3.is_nan()
t4 = Transform(q4, v4)
assert not t4.is_finite()
assert t4.is_nan()
def scatter(self, r_in, rec):
outward_normal = Vec3()
reflected = Vec3.reflect(r_in.direction,rec["normal"])
ni_over_nt = 0.0
attenuation = Vec3(1.0,1.0,1.0)
cosine = 0.0
if Vec3.dot(r_in.direction,rec["normal"]) > 0:
outward_normal = -rec["normal"]
ni_over_nt = self.ref_idx
cosine = self.ref_idx * Vec3.dot(r_in.direction,rec["normal"])/ r_in.direction.length()
else:
outward_normal = rec["normal"]
ni_over_nt = 1.0 / self.ref_idx
cosine = -Vec3.dot(r_in.direction,rec["normal"])/ r_in.direction.length()
scattered = Ray()
reflect_prob = 0.0
refracted = Vec3.refract(r_in.direction,outward_normal,ni_over_nt)
if refracted is not None:
reflect_prob = schlick(cosine,self.ref_idx)
else:
reflect_prob = 1.0
if random() < reflect_prob:
scattered = Ray(rec["p"],reflected)
else:
scattered = Ray(rec["p"],refracted)
return attenuation, scattered
def colored_sphere(i, j, nx, ny):
s = Sphere(Vec3(0, 0, -1), 0.5)
r = origin_to_pixel(i, j, nx, ny)
if s.hit(r, 0, float("inf")):
return (s.normal + Vec3(1, 1, 1)) * 255.99 / 2
else:
return blue_to_white(i, j, nx, ny)
def get_plane(self, sp1, sp2, sp3, dist_21, dist_23, ang_13):
""" Returns the plane object defined by three points projected onto some unknown perspective.
:param sp1: screen point 1
:param sp2: screen point 2
:param sp3: screen point 3
:param dist_21: real distance from 2 to 1
:param dist_23: real distance from 2 to 3
:param ang_13: angle between vectors sp1-sp2 and sp2-sp3
:return: plane in real coordinates
"""
l01 = self.line(sp1)
l02 = self.line(sp2)
l03 = self.line(sp3)
param = 0
a = l02.get_point(param)
t1 = l01.get_point_at_dist(a, dist_21, line.Direction.POSITIVE)
t3 = l03.get_point_at_dist(a, dist_23, line.Direction.POSITIVE)
ang = Vec3.angle_between(t1 - a, t3 - a)
while abs(ang - ang_13) > 0.001:
param += 10.0 * abs(ang - ang_13)
while True:
a = l02.get_point(param)
try:
t1 = l01.get_point_at_dist(a, dist_21, line.Direction.POSITIVE)
t3 = l03.get_point_at_dist(a, dist_23, line.Direction.POSITIVE)
break
except ValueError:
param -= 0.1 * abs(ang - ang_13)
ang = Vec3.angle_between(t1 - a, t3 - a)
i = inspect.getframeinfo(inspect.currentframe())
return Plane(a, t1 - a, t3 - a)
def test_rotate_vec():
v = Vec3(1, 1, 0)
q1 = Quat.from_rotation_on_axis(0, np.pi / 3)
q2 = Quat.from_rotation_on_axis(1, np.pi / 3)
q3 = Quat.from_rotation_on_axis(2, np.pi / 3)
# forward rotation
v1 = q1.rotate(v)
v2 = q2.rotate(v)
v3 = q3.rotate(v)
theta1 = (60) * np.pi / 180.0
v1_true = Vec3(1, math.cos(theta1), math.sin(theta1))
v2_true = Vec3(math.cos(theta1), 1, -math.sin(theta1))
theta2 = (45 + 60) * np.pi / 180.0
v3_true = math.sqrt(2) * Vec3(math.cos(theta2), math.sin(theta2), 0)
assert v1 == v1_true
assert v2 == v2_true
assert v3 == v3_true
# inverse rotate
v1_rev = q1.inverse_rotate(v1_true)
v2_rev = q2.inverse_rotate(v2_true)
v3_rev = q3.inverse_rotate(v3_true)
assert v == v1_rev
assert v == v2_rev
assert v == v3_rev
def random_in_unit_sphere_3():
"""Get a random vector inside the 3d unit sphere."""
while True:
p = Vec3(random(), random(), random()) * 2.0 - Vec3(1, 1, 1)
if p.squared_length < 1.0:
return p
def scatter(self, r_in, rec, attenuation, scattered):
reflected = reflect(r_in.direction, rec.normal)
attenuation = Vec3(1, 1, 1)
refracted = Vec3()
if r_in.direction.dot(rec.normal) > 0.0:
outward_normal = -rec.normal
ni_over_nt = self.ref_idx
cosine = r_in.direction.dot(rec.normal) / r_in.direction.length
cosine = sqrt(1.0 - self.ref_idx * self.ref_idx *
(1.0 - cosine * cosine))
else:
outward_normal = rec.normal
ni_over_nt = 1.0 / self.ref_idx
cosine = -r_in.direction.dot(rec.normal) / r_in.direction.length
if refract(r_in.direction, outward_normal, ni_over_nt, refracted):
reflect_prob = schlick(cosine, self.ref_idx)
else:
reflect_prob = 1.0
if random() < reflect_prob:
scattered.update(rec.p, reflected)
else:
scattered.update(rec.p, refracted)
return True
def main():
# G = 1
# M1 = 1
# M2 = 1
R = 1
v = math.sqrt(1 / (4 * R))
r1 = Vec3(-R, 0, 0)
r2 = Vec3(R, 0, 0)
v1 = Vec3(0, -v, 0)
v2 = Vec3(0, v, 0)
time_step = 0.01
r1_data, r2_data = [], []
n_steps = 100000
for i in range(n_steps + 1):
r1_data.append(r1)
r2_data.append(r2)
r1, r2, v1, v2 = leapfrog(r1, r2, v1, v2, time_step)
# print("\rcalculation progress: t = {:.2f} / {:.2f} ({:.2f}%)".format(i * time_step, n_steps * time_step,
# 100 * i / n_steps),
# end="")
print(runge(r1, v1))
print(runge(r2, v2))
x1_data = [p.x for p in r1_data]
y1_data = [p.y for p in r1_data]
x2_data = [p.x for p in r2_data]
y2_data = [p.y for p in r2_data]
plt.figure(figsize=(8, 8))
plt.plot(x1_data, y1_data)
plt.plot(x2_data, y2_data)
plt.xlim(-5, 5)
plt.ylim(-5, 5)
plt.show()
def __init__(self,
look_from: Vec3 = Vec3(3.0, 3.0, 2.0),
look_at: Vec3 = Vec3(0.0, 0.0, -1.0),
vec_up: Vec3 = Vec3(0.0, 1.0, 0.0),
v_fov: float = 90.0,
aspect: float = 1.0,
aperture: float = 0.0,
focus_dist: float = 1.0):
self.lens_radius = aperture / 2.0
theta = v_fov * 3.14159 / 180.0
half_height = math.tan(theta / 2.0)
half_width = aspect * half_height
w = unit_vector(look_from - look_at)
self.u = unit_vector(vec_up.cross(w))
self.v = w.cross(self.u)
self.origin = look_from
self.upper_left_corner = look_from - \
half_width*self.u*focus_dist + \
half_height*self.v*focus_dist - w*focus_dist
self.horizontal = 2 * half_width * self.u * focus_dist
self.vertical = -2 * half_height * self.v * focus_dist
def two_spheres():
l = []
checker = CheckerTexture(ConstantTexture(Vec3(0.2, 0.3, 0.1)),
ConstantTexture(Vec3(0.9, 0.9, 0.9)))
l.append(Sphere(Vec3(0.0, -10.0, 0.0), 10, Lambertian(checker)))
l.append(Sphere(Vec3(0.0, 10.0, 0.0), 10, Lambertian(checker)))
return HitableList(l)
def random_in_unit_disk_2():
"""Get a random vector inside the unit sphere."""
while True:
p = Vec3(random(), random(), 0) * 2.0 - Vec3(1, 1, 0)
if p.dot(p) < 1.0:
return p
def main():
nx = 200
ny = 100
ns = 30
f = open("generated_images/first_world.ppm","w")
f.write("P3\n%d %d\n255\n"%(nx,ny))
cam = Camera()
world = Object3DList(
[Sphere(Vec3(0.0,0.0,-1.0), 0.5),
Sphere(Vec3(0.0,-100.5,-1.0),100)])
# Note break with guide convention, vertical pixels start with index 0 at top
for y in range(0,ny):
for x in range(0,nx):
col = Vec3(0.0,0.0,0.0)
for _ in range(0, ns):
u = (float(x)+random.random())/float(nx)
v = (float(y)+random.random())/float(ny)
r = cam.get_ray(u, v)
col += color(r, world)
col /= ns
f.write(col.color_string(scale=255.99))
f.close()
def scatter(self, ray, rec, srec):
srec.is_specular = True
srec.pdf_ptr = 0
srec.attenuation = Vec3(1.0, 1.0, 1.0)
outward_normal = Vec3()
reflected = ray.dir.reflect(rec.normal)
refracted = Vec3()
if ray.dir.dot(rec.normal) > 0:
outward_normal = -rec.normal
ni_over_nt = self.ref_idx
cosine = self.ref_idx * ray.dir.dot(rec.normal) / ray.dir.length()
else:
outward_normal = rec.normal
ni_over_nt = 1.0 / self.ref_idx
cosine = -ray.dir.dot(rec.normal) / ray.dir.length()
if self.refract(ray.dir, outward_normal, ni_over_nt, refracted):
reflect_prob = self.schlick(cosine, self.ref_idx)
else:
reflect_prob = 1.0
if random() < reflect_prob:
srec.specular_ray = Ray(rec.p, reflected)
else:
srec.specular_ray = Ray(rec.p, refracted)
return True
def getSegmentsFromIntersections( solidXIntersectionList, y, z ):
"Get endpoint segments from the intersections."
segments = []
xIntersectionList = []
fill = False
solid = False
solidTable = {}
solidXIntersectionList.sort( compareSolidXByX )
for solidX in solidXIntersectionList:
solidXYInteger = int( solidX.imag )
if solidXYInteger >= 0:
toggleHashtable( solidTable, solidXYInteger, "" )
else:
fill = not fill
oldSolid = solid
solid = ( len( solidTable ) == 0 and fill )
if oldSolid != solid:
xIntersectionList.append( solidX.real )
for xIntersectionIndex in range( 0, len( xIntersectionList ), 2 ):
firstX = xIntersectionList[ xIntersectionIndex ]
secondX = xIntersectionList[ xIntersectionIndex + 1 ]
endpointFirst = Endpoint()
endpointSecond = Endpoint().getFromOtherPoint( endpointFirst, Vec3( secondX, y, z ) )
endpointFirst.getFromOtherPoint( endpointSecond, Vec3( firstX, y, z ) )
segment = ( endpointFirst, endpointSecond )
segments.append( segment )
return segments
def main():
with open("output.ppm", "w") as f:
nx, ny, ns = 200, 100, 100
header = "P3\n{} {}\n255\n".format(nx, ny)
f.write(header)
camera = Camera()
sphere1 = Sphere(Vec3(0.0, 0.0, -1.0), 0.5,
Lambertian(Vec3(0.8, 0.3, 0.3)))
sphere2 = Sphere(Vec3(0.0, -100.5, -1.0), 100.0,
Lambertian(Vec3(0.8, 0.8, 0.0)))
sphere3 = Sphere(Vec3(1.0, 0.0, -1.0), 0.5, Metal(Vec3(0.8, 0.6, 0.2)))
sphere4 = Sphere(Vec3(-1.0, 0.0, -1.0), 0.5, Metal(Vec3(0.8, 0.8,
0.8)))
world = Hitable_list([sphere1, sphere2, sphere3, sphere4])
for j in range(ny - 1, -1, -1):
for i in range(nx):
col = Vec3(0.0, 0.0, 0.0)
for k in range(0, ns):
u = float(i + random()) / float(nx)
v = float(j + random()) / float(ny)
ray = camera.get_ray(u, v)
col += color(ray, world, 0)
col /= float(ns)
col = Vec3(sqrt(col.e0), sqrt(col.e1), sqrt(col.e2))
ir = int(255.99 * col.r())
ig = int(255.99 * col.g())
ib = int(255.99 * col.b())
line = "{} {} {}\n".format(ir, ig, ib)
f.write(line)
def cornell_box():
'''Generate a scene with a Cornell box, using rectangles and boxes'''
world = HittableList()
red = Lambertian(Color(0.65, 0.05, 0.05))
white = Lambertian(Color(0.73, 0.73, 0.73))
green = Lambertian(Color(0.12, 0.45, 0.15))
light = DiffuseLight(Color(15, 15, 15))
aluminum = Metal(Color(0.8, 0.85, 0.88), 0.0)
glass = Dielectric(1.5)
box1 = Box(Point3(0, 0, 0), Point3(165, 330, 165), aluminum)
box1 = RotateY(box1, 15)
box1 = Translate(box1, Vec3(265, 0, 295))
box2 = Box(Point3(0, 0, 0), Point3(165, 165, 165), white)
box2 = RotateY(box2, -18)
box2 = Translate(box2, Vec3(130, 0, 65))
world.add(yzRect(0, 555, 0, 555, 555, green))
world.add(yzRect(0, 555, 0, 555, 0, red))
world.add(xzRect(0, 555, 0, 555, 555, white))
world.add(xzRect(0, 555, 0, 555, 0, white))
world.add(xyRect(0, 555, 0, 555, 555, white))
world.add(box1)
world.add(box2)
world.add(FlipFace(xzRect(213, 343, 227, 332, 554, light)))
return world
def hit_sphere(center,radius,r): oc = r.origin -center a = Vec3.dot(r.direction,r.direction) b = 2.0 * Vec3.dot(oc,r.direction) c = Vec3.dot(oc,oc) - radius * radius discriminant = b*b - 4*a*c return discriminant > 0
def hit(self,r,t_min,t_max):
rec = None
oc = r.origin - self.center(r.time)
a = Vec3.dot(r.direction,r.direction)
b = Vec3.dot(oc,r.direction)
c = Vec3.dot(oc,oc) - (self.radius*self.radius)
discriminant = (b*b) - (a*c)
if discriminant > 0:
rec = {}
temp = (-b - sqrt(discriminant)) / a
if t_min < temp < t_max:
rec["t"] = temp
rec["p"] = r.point_at_parameter(rec["t"])
rec["u"],rec["v"] =getSphereUv((rec["p"] - self.center) / self.radius)
rec["normal"] = (rec["p"] - self.center(r.time)) / self.radius
rec["material"] = self.material
return rec
temp = (-b + sqrt(discriminant)) / a
if t_min < temp < t_max:
rec["t"] = temp
rec["p"] = r.point_at_parameter(rec["t"])
rec["u"],rec["v"] =getSphereUv((rec["p"] - self.center) / self.radius)
rec["normal"] = (rec["p"] - self.center(r.time)) / self.radius
rec["material"] = self.material
return rec
return None
def random_in_unit_sphere():
"""Return a random vector in the unit sphere."""
while True:
p = Vec3(random(), random(), random()) * 2.0 - Vec3(1.0, 1.0, 1.0)
if p.squared_length < 1.0:
return p
def __init__(self):
"""A camera clas."""
self.origin = Vec3(0.0, 0.0, 0.0)
self.lower_left_corner = Vec3(-2.0, -1.0, -1.0)
self.horizontal = Vec3(4.0, 0.0, 0.0)
self.vertical = Vec3(0.0, 2.0, 0.0)
def test_dot():
v1 = Vec3(0, 1, 2)
v2 = Vec3(3, 4, 5)
res = v1.dot(v2)
assert res == 14
def __init__(self, h):
nz = cos(radians(h))
nx = sqrt(1 - nz * nz)
height = nz / nx
#print(nx, nz, height)
self.lside = Plane(Vec3(0.0, 0.0, -height), Vec3(nx, 0.0, nz))
self.rside = Plane(Vec3(0.0, 0.0, -height), Vec3(-nx, 0.0, nz))
def __init__(self):
self.position = Vec3()
self.normal = Vec3()
self.t = 0.0
self.frontFacing = False
def random_in_unit_sphere():
# p = Vec3(0, 0, 0)
while True:
p = Vec3(random(), random(), random()) * 2.0 - Vec3(1.0, 1.0, 1.0)
if p.squared_length < 1.0:
break
return p
def main():
nx = 200
ny = 150
ns = 100
print("P3\n", nx, " ", ny, "\n255")
world = two_spheres()
lookfrom = Vec3(13, 2, 3)
lookat = Vec3(0, 0, 0)
dist_to_focus = 10.0
aperture = 0.0
cam = Camera(lookfrom, lookat, Vec3(0, 1, 0), 20, nx / ny, aperture,
dist_to_focus, 0.0, 1.0)
for j in reversed(range(ny)):
for i in range(nx):
col = Vec3(0, 0, 0)
for s in range(ns):
u = (i + random()) / nx
v = (j + random()) / ny
r = cam.get_ray(u, v)
p = r.point_at_parameter(2.0)
col += color(r, world, 0)
col /= ns
col = Vec3(sqrt(col[0]), sqrt(col[1]), sqrt(col[2]))
ir = int(255.99 * col[0])
ig = int(255.99 * col[1])
ib = int(255.99 * col[2])
print(ir, " ", ig, " ", ib)
def scatter(self, r_in,rec):
reflected = Vec3.reflect(Vec3.unit_vector(r_in.direction),rec["normal"])
scattered = Ray(rec["p"],reflected + self.fuzz * Material.random_in_unit_sphere())
attenuation = self.albedo
if Vec3.dot(scattered.direction,rec["normal"]) > 0:
return attenuation,scattered
else:
return None,None
def color(ray):
t = hit_sphere(Vec3(0, 0, -1), 0.5, ray)
if t > 0.0:
N = (ray.point_at_parameter(t) - Vec3(0, 0, -1)).unit_vector()
return Vec3(N.x() + 1, N.y() + 1, N.z() + 1) * 0.5
unit_direction = ray.direction.unit_vector()
t = 0.5 * (unit_direction.y() + 1.0)
return Vec3(1.0, 1.0, 1.0) * (1.0 - t) + Vec3(0.5, 0.7, 1.0) * t
def __init__(self,lookfrom,lookat,vup,vfov,aspect,aperture,focus_dist): self.lens_radius = aperture /2 theta = vfov * math.pi/180 half_height = math.tan(theta/2) half_width = aspect * half_height self.origin = lookfrom self.w = Vec3.unit_vector(lookfrom -lookat) self.u = Vec3.unit_vector(Vec3.cross(vup,self.w)) self.v = Vec3.cross(self.w,self.u) self.lower_left_corner = self.origin - half_width*focus_dist*self.u -half_height*focus_dist*self.v -focus_dist*self.w self.horizontal = 2*half_width*focus_dist*self.u self.vertical = 2*half_height*focus_dist*self.v
def color(r,world):
rec = world.hit(r,0.0,float('inf'))
if rec is not None:
target = rec["p"]+rec["normal"] + random_in_unit_sphere()
return 0.5 * color(Ray(rec["p"],target-rec["p"]),world)
else:
unit_direction = Vec3.unit_vector(r.direction)
t = 0.5*(unit_direction.y +1.0)
return (1.0-t)*Vec3(1.0,1.0,1.0) + t*Vec3(0.5,0.7,1.0)
def hit(self,r,t_min,t_max):
rec = None
oc = r.origin - self.center
a = Vec3.dot(r.direction,r.direction)
b = Vec3.dot(oc,r.direction)
c = Vec3.dot(oc,oc) - (self.radius*self.radius)
discriminant = (b*b) - (a*c)
if discriminant > 0:
rec = {}
temp = (-b - sqrt(discriminant)) / a
if t_min < temp < t_max:
rec["t"] = temp
rec["p"] = r.point_at_parameter(rec["t"])
rec["normal"] = (rec["p"] - self.center) / self.radius
return rec
temp = (-b + sqrt(discriminant)) / a
if t_min < temp < t_max:
rec["t"] = temp
rec["p"] = r.point_at_parameter(rec["t"])
rec["normal"] = (rec["p"] - self.center) / self.radius
return rec
return None
def color(r,world,depth):
rec = world.hit(r,0.001,float('inf'))
if rec is not None:
if depth >= 50:
return Vec3(0,0,0)
attenuation,scattered =rec["material"].scatter(r,rec)
if attenuation is not None:
return attenuation * color(scattered,world,depth +1)
else:
return Vec3(0,0,0)
else:
unit_direction = Vec3.unit_vector(r.direction)
t = 0.5*(unit_direction.y +1.0)
return (1.0-t)*Vec3(1.0,1.0,1.0) + t*Vec3(0.5,0.7,1.0)
def color(r): unit_direction = Vec3.unit_vector(r.direction) t = 0.5*(unit_direction.y +1.0) return (1.0-t)*Vec3(1.0,1.0,1.0) + t*Vec3(0.5,0.7,1.0)
def get_dist_to_point(self, point):
return abs(Vec3.from_to(point, self.get_closest_point_to(point)))
def get_closest_point_to(self, point):
n = self.get_normal()
return point - (Vec3.dot(Vec3.from_to(self.origin, point), n)*n)
def get_normal(self):
return Vec3.cross(self.direction1, self.direction2).get_unit()
def random_in_unit_sphere(cls):
while True:
p = 2.0*Vec3(random(),random(),random()) - Vec3(1,1,1)
if Vec3.dot(p,p) < 1.0:
return p
def random_in_unit_disk():
while True:
p = 2.0 * Vec3(random(),random(),0) -Vec3(1,1,0)
if Vec3.dot(p,p) < 1.0:
return p
def color(r):
if hit_sphere(Vec3(0,0,-1),0.5,r):
return Vec3(1,0,0)
unit_direction = Vec3.unit_vector(r.direction)
t = 0.5*(unit_direction.y +1.0)
return (1.0-t)*Vec3(1.0,1.0,1.0) + t*Vec3(0.5,0.7,1.0)
def get_closest_point_to(self, point):
l = self.direction.get_unit()
return self.origin + (Vec3.dot(Vec3.from_to(self.origin, point), l)*l)
