def get_ray(self, s, t, sample):
rd = Vector3.random_in_unit_disk(s, t, sample) * self.lens_radius
# rd = Vector3.concentric_sample_disk(s*2-1, t*2-1) * self.lens_radius
offset = self.u * rd.x + self.v * rd.y
return Ray(
self.origin + offset,
self.lower_left_corner + self.horizontal*s + self.vertical*t - self.origin - offset)
def __init__(self, pos, t):
self.pos = pos
self.normal = Vector3(0, 0, 0)
self.t = t
self.material = None
self.front_face = False
def scatter(self, r_in, rec):
reflected = Vector3.reflect(r_in.direction.normalized(), rec.normal)
# Catch degenerate scatter direction
if reflected.near_zero():
reflected = rec.normal
scattered = Ray(rec.pos, reflected)
attenuation = self.albedo
return scattered.direction.dot(rec.normal) > 0, scattered, attenuation
def scatter(self, r_in, rec):
scatter_direction = rec.normal + Vector3.random_unit_vector()
# Catch degenerate scatter direction
if scatter_direction.near_zero():
scatter_direction = rec.normal
scattered = Ray(rec.pos, scatter_direction)
attenuation = self.albedo
return True, scattered, attenuation
def hit(self, r, t_min, t_max, recc=None):
temp_rec = HitRecord(Vector3(0, 0, 0), 0.0)
hit_anything = False
closest_so_far = t_max
rec = None
for obj in self.objects:
if obj.hit(r, t_min, closest_so_far, temp_rec):
hit_anything = True
closest_so_far = temp_rec.t
rec = temp_rec
return hit_anything, rec
def ray_colour(r, background, world, depth):
hit, rec = world.hit(r, 0.001, utils.INFINITY)
if depth <= 0:
return Vector3(0, 0, 0)
if not hit:
return background
emitted = rec.material.emitted()
result, scattered, attenuation = rec.material.scatter(r, rec)
if not result:
return emitted
return emitted + attenuation.mul(ray_colour(scattered, background, world, depth-1))
def scatter(self, r_in, rec):
return True, Ray(Vector3(0, 0, 0),
Vector3(0, 0, 0)), HitRecord(Vector3(0, 0, 0), 0.0)
def emitted(self):
return Vector3(0, 0, 0)
def main():
# Image
aspect_ratio = 16.0 / 9.0
image_width = 256
image_height = image_width/aspect_ratio
background = Vector3(0, 0, 0)
samples_per_pixel = 20
max_depth = 1
# World
world = HittableList()
# material_ground = Lambertian(Vector3(0.8, 0.8, 0.0))
# material_center = Lambertian(Vector3(0.7, 0.3, 0.3))
# material_left = Metal(Vector3(0.8, 0.8, 0.8))
material_emissive = DiffuseLight(Vector3(1,1,1), Vector3(1,1,1))
# material_right = Metal(Vector3(0.8, 0.6, 0.2))
# world.append(Sphere(Vector3(0, 0, -1), 0.5, material_center))
# world.append(Sphere(Vector3(1, 0.5, -0.5), 1, material_emissive))
# world.append(Sphere(Vector3(-1, 0, -1), 0.5, material_right))
# world.append(Sphere(Vector3(0, -100.5, -1), 100, material_ground))
sphere_count = 35
sphere_dist = 100
for i in range(0, sphere_count):
world.append(Sphere(Vector3(utils.rand_range(-50, 50), utils.rand_range(-40, 40),
sphere_dist),
1,
material_emissive))
# Camera
look_from = Vector3(0, 0, 0)
look_at = Vector3(0, 0, 1)
v_up = Vector3(0, 1, 0)
dist_to_focus = (look_from - look_at).length()
f_stop = 8
aperture = 1/f_stop
cam = Camera(look_from, look_at, v_up, 30.0, aspect_ratio, aperture, dist_to_focus)
# Render
render_data = list()
print("Commencing Rendering.")
start_time = datetime.now()
for j in reversed(range(0, int(image_height))):
print("Scanlines remaining: %s" % j)
for i in range(0, image_width):
pixel_colour = Vector3(0, 0, 0)
for s in range(0, samples_per_pixel):
u = (i + utils.rand()) / (image_width-1)
v = (j + utils.rand()) / (image_height-1)
r = cam.get_ray(u, v, s)
pixel_colour += ray_colour(r, background, world, max_depth)
render_data.append(colour.write_colour(pixel_colour, samples_per_pixel))
print("\nDone.\nTime Spent: %s" % (datetime.now() - start_time))
file = image.write_image(
width=image_width,
height=image_height,
data=render_data
)
return file