def test_antialiasing(self):
num_of_rays = 0
small_image = HdrImage(width=1, height=1)
camera = OrthogonalCamera(aspect_ratio=1)
tracer = ImageTracer(small_image,
camera,
samples_per_side=10,
pcg=PCG())
def trace_ray(ray: Ray) -> Color:
nonlocal num_of_rays
point = ray.at(1)
# Check that all the rays intersect the screen within the region [−1, 1] × [−1, 1]
assert pytest.approx(0.0) == point.x
assert -1.0 <= point.y <= 1.0
assert -1.0 <= point.z <= 1.0
num_of_rays += 1
return Color(0.0, 0.0, 0.0)
tracer.fire_all_rays(trace_ray)
# Check that the number of rays that were fired is what we expect (10²)
assert num_of_rays == 100
def testFlatRenderer(self):
sphere_color = Color(1.0, 2.0, 3.0)
sphere = Sphere(transformation=translation(Vec(2, 0, 0)) *
scaling(Vec(0.2, 0.2, 0.2)),
material=Material(brdf=DiffuseBRDF(
pigment=UniformPigment(sphere_color))))
image = HdrImage(width=3, height=3)
camera = OrthogonalCamera()
tracer = ImageTracer(image=image, camera=camera)
world = World()
world.add_shape(sphere)
renderer = FlatRenderer(world=world)
tracer.fire_all_rays(renderer)
assert image.get_pixel(0, 0).is_close(BLACK)
assert image.get_pixel(1, 0).is_close(BLACK)
assert image.get_pixel(2, 0).is_close(BLACK)
assert image.get_pixel(0, 1).is_close(BLACK)
assert image.get_pixel(1, 1).is_close(sphere_color)
assert image.get_pixel(2, 1).is_close(BLACK)
assert image.get_pixel(0, 2).is_close(BLACK)
assert image.get_pixel(1, 2).is_close(BLACK)
assert image.get_pixel(2, 2).is_close(BLACK)
class TestImageTracer(unittest.TestCase):
def setUp(self) -> None:
self.image = HdrImage(width=4, height=2)
self.camera = PerspectiveCamera(aspect_ratio=2)
self.tracer = ImageTracer(image=self.image, camera=self.camera)
def test_orientation(self):
top_left_ray = self.tracer.fire_ray(0, 0, u_pixel=0.0, v_pixel=0.0)
assert Point(0.0, 2.0, 1.0).is_close(top_left_ray.at(1.0))
bottom_right_ray = self.tracer.fire_ray(3, 1, u_pixel=1.0, v_pixel=1.0)
assert Point(0.0, -2.0, -1.0).is_close(bottom_right_ray.at(1.0))
def test_uv_sub_mapping(self):
# Here we're cheating: we are asking `ImageTracer.fire_ray` to fire one ray *outside*
# the pixel we're specifying
ray1 = self.tracer.fire_ray(0, 0, u_pixel=2.5, v_pixel=1.5)
ray2 = self.tracer.fire_ray(2, 1, u_pixel=0.5, v_pixel=0.5)
assert ray1.is_close(ray2)
def test_image_coverage(self):
self.tracer.fire_all_rays(lambda ray: Color(1.0, 2.0, 3.0))
for row in range(self.image.height):
for col in range(self.image.width):
assert self.image.get_pixel(col, row) == Color(1.0, 2.0, 3.0)
def demo(width, height, angle_deg, orthogonal, pfm_output, png_output):
image = HdrImage(width, height)
# Create a world and populate it with a few shapes
world = World()
for x in [-0.5, 0.5]:
for y in [-0.5, 0.5]:
for z in [-0.5, 0.5]:
world.add(
Sphere(transformation=translation(Vec(x, y, z)) *
scaling(Vec(0.1, 0.1, 0.1))))
# Place two other balls in the bottom/left part of the cube, so
# that we can check if there are issues with the orientation of
# the image
world.add(
Sphere(transformation=translation(Vec(0.0, 0.0, -0.5)) *
scaling(Vec(0.1, 0.1, 0.1))))
world.add(
Sphere(transformation=translation(Vec(0.0, 0.5, 0.0)) *
scaling(Vec(0.1, 0.1, 0.1))))
# Initialize a camera
camera_tr = rotation_z(angle_deg=angle_deg) * translation(
Vec(-1.0, 0.0, 0.0))
if orthogonal:
camera = OrthogonalCamera(aspect_ratio=width / height,
transformation=camera_tr)
else:
camera = PerspectiveCamera(aspect_ratio=width / height,
transformation=camera_tr)
# Run the ray-tracer
tracer = ImageTracer(image=image, camera=camera)
def compute_color(ray: Ray) -> Color:
if world.ray_intersection(ray):
return WHITE
else:
return BLACK
tracer.fire_all_rays(compute_color)
# Save the HDR image
with open(pfm_output, "wb") as outf:
image.write_pfm(outf)
print(f"HDR demo image written to {pfm_output}")
# Apply tone-mapping to the image
image.normalize_image(factor=1.0)
image.clamp_image()
# Save the LDR image
with open(png_output, "wb") as outf:
image.write_ldr_image(outf, "PNG")
print(f"PNG demo image written to {png_output}")
class TestImageTracer(unittest.TestCase):
def setUp(self) -> None:
self.image = HdrImage(width=4, height=2)
self.camera = PerspectiveCamera(aspect_ratio=2)
self.tracer = ImageTracer(image=self.image, camera=self.camera)
def test_orientation(self):
top_left_ray = self.tracer.fire_ray(0, 0, u_pixel=0.0, v_pixel=0.0)
assert Point(0.0, 2.0, 1.0).is_close(top_left_ray.at(1.0))
bottom_right_ray = self.tracer.fire_ray(3, 1, u_pixel=1.0, v_pixel=1.0)
assert Point(0.0, -2.0, -1.0).is_close(bottom_right_ray.at(1.0))
def test_uv_sub_mapping(self):
# Here we're cheating: we are asking `ImageTracer.fire_ray` to fire one ray *outside*
# the pixel we're specifying
ray1 = self.tracer.fire_ray(0, 0, u_pixel=2.5, v_pixel=1.5)
ray2 = self.tracer.fire_ray(2, 1, u_pixel=0.5, v_pixel=0.5)
assert ray1.is_close(ray2)
def test_image_coverage(self):
self.tracer.fire_all_rays(lambda ray: Color(1.0, 2.0, 3.0))
for row in range(self.image.height):
for col in range(self.image.width):
assert self.image.get_pixel(col, row) == Color(1.0, 2.0, 3.0)
def test_antialiasing(self):
num_of_rays = 0
small_image = HdrImage(width=1, height=1)
camera = OrthogonalCamera(aspect_ratio=1)
tracer = ImageTracer(small_image,
camera,
samples_per_side=10,
pcg=PCG())
def trace_ray(ray: Ray) -> Color:
nonlocal num_of_rays
point = ray.at(1)
# Check that all the rays intersect the screen within the region [−1, 1] × [−1, 1]
assert pytest.approx(0.0) == point.x
assert -1.0 <= point.y <= 1.0
assert -1.0 <= point.z <= 1.0
num_of_rays += 1
return Color(0.0, 0.0, 0.0)
tracer.fire_all_rays(trace_ray)
# Check that the number of rays that were fired is what we expect (10²)
assert num_of_rays == 100
def setUp(self) -> None:
self.image = HdrImage(width=4, height=2)
self.camera = PerspectiveCamera(aspect_ratio=2)
self.tracer = ImageTracer(image=self.image, camera=self.camera)
def demo(width, height, algorithm, pfm_output, png_output, num_of_rays,
max_depth, init_state, init_seq, samples_per_pixel, declare_float,
input_scene_name):
samples_per_side = int(sqrt(samples_per_pixel))
if samples_per_side**2 != samples_per_pixel:
print(
f"Error, the number of samples per pixel ({samples_per_pixel}) must be a perfect square"
)
return
variables = build_variable_table(declare_float)
with open(input_scene_name, "rt") as f:
try:
scene = parse_scene(input_file=InputStream(
stream=f, file_name=input_scene_name),
variables=variables)
except GrammarError as e:
loc = e.location
print(f"{loc.file_name}:{loc.line_num}:{loc.col_num}: {e.message}")
sys.exit(1)
image = HdrImage(width, height)
print(f"Generating a {width}×{height} image")
# Run the ray-tracer
tracer = ImageTracer(image=image,
camera=scene.camera,
samples_per_side=samples_per_side)
if algorithm == "onoff":
print("Using on/off renderer")
renderer = OnOffRenderer(world=scene.world, background_color=BLACK)
elif algorithm == "flat":
print("Using flat renderer")
renderer = FlatRenderer(world=scene.world, background_color=BLACK)
elif algorithm == "pathtracing":
print("Using a path tracer")
renderer = PathTracer(
world=scene.world,
pcg=PCG(init_state=init_state, init_seq=init_seq),
num_of_rays=num_of_rays,
max_depth=max_depth,
)
elif algorithm == "pointlight":
print("Using a point-light tracer")
renderer = PointLightRenderer(world=scene.world,
background_color=BLACK)
else:
print(f"Unknown renderer: {algorithm}")
sys.exit(1)
def print_progress(row, col):
print(f"Rendering row {row + 1}/{image.height}\r", end="")
start_time = process_time()
tracer.fire_all_rays(renderer, callback=print_progress)
elapsed_time = process_time() - start_time
print(f"Rendering completed in {elapsed_time:.1f} s")
# Save the HDR image
with open(pfm_output, "wb") as outf:
image.write_pfm(outf)
print(f"HDR demo image written to {pfm_output}")
# Apply tone-mapping to the image
image.normalize_image(factor=1.0)
image.clamp_image()
# Save the LDR image
with open(png_output, "wb") as outf:
image.write_ldr_image(outf, "PNG")
print(f"PNG demo image written to {png_output}")