def test_rotations(self):
assert rotation_x(0.1).is_consistent()
assert rotation_y(0.1).is_consistent()
assert rotation_z(0.1).is_consistent()
assert (rotation_x(angle_deg=90) * VEC_Y).is_close(VEC_Z)
assert (rotation_y(angle_deg=90) * VEC_Z).is_close(VEC_X)
assert (rotation_z(angle_deg=90) * VEC_X).is_close(VEC_Y)
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}")
def parse_transformation(input_file, scene: Scene):
result = Transformation()
while True:
transformation_kw = expect_keywords(input_file, [
KeywordEnum.IDENTITY,
KeywordEnum.TRANSLATION,
KeywordEnum.ROTATION_X,
KeywordEnum.ROTATION_Y,
KeywordEnum.ROTATION_Z,
KeywordEnum.SCALING,
])
if transformation_kw == KeywordEnum.IDENTITY:
pass # Do nothing (this is a primitive form of optimization!)
elif transformation_kw == KeywordEnum.TRANSLATION:
expect_symbol(input_file, "(")
result *= translation(parse_vector(input_file, scene))
expect_symbol(input_file, ")")
elif transformation_kw == KeywordEnum.ROTATION_X:
expect_symbol(input_file, "(")
result *= rotation_x(expect_number(input_file, scene))
expect_symbol(input_file, ")")
elif transformation_kw == KeywordEnum.ROTATION_Y:
expect_symbol(input_file, "(")
result *= rotation_y(expect_number(input_file, scene))
expect_symbol(input_file, ")")
elif transformation_kw == KeywordEnum.ROTATION_Z:
expect_symbol(input_file, "(")
result *= rotation_z(expect_number(input_file, scene))
expect_symbol(input_file, ")")
elif transformation_kw == KeywordEnum.SCALING:
expect_symbol(input_file, "(")
result *= scaling(parse_vector(input_file, scene))
expect_symbol(input_file, ")")
# We must peek the next token to check if there is another transformation that is being
# chained or if the sequence ends. Thus, this is a LL(1) parser.
next_kw = input_file.read_token()
if (not isinstance(next_kw, SymbolToken)) or (next_kw.symbol != "*"):
# Pretend you never read this token and put it back!
input_file.unread_token(next_kw)
break
return result
def test_perspective_camera_transform(self):
cam = PerspectiveCamera(transformation=translation(-VEC_Y * 2.0) *
rotation_z(pi / 2.0))
ray = cam.fire_ray(0.5, 0.5)
assert ray.at(1.0).is_close(Point(0.0, -2.0, 0.0))
def test_orthogonal_camera_transform(self):
cam = OrthogonalCamera(transformation=translation(-VEC_Y * 2.0) *
rotation_z(angle_deg=90))
ray = cam.fire_ray(0.5, 0.5)
assert ray.at(1.0).is_close(Point(0.0, -2.0, 0.0))
def test_parser(self):
stream = StringIO("""
float clock(150)
material sky_material(
diffuse(uniform(<0, 0, 0>)),
uniform(<0.7, 0.5, 1>)
)
# Here is a comment
material ground_material(
diffuse(checkered(<0.3, 0.5, 0.1>,
<0.1, 0.2, 0.5>, 4)),
uniform(<0, 0, 0>)
)
material sphere_material(
specular(uniform(<0.5, 0.5, 0.5>)),
uniform(<0, 0, 0>)
)
plane (sky_material, translation([0, 0, 100]) * rotation_y(clock))
plane (ground_material, identity)
sphere(sphere_material, translation([0, 0, 1]))
camera(perspective, rotation_z(30) * translation([-4, 0, 1]), 1.0, 2.0)
""")
scene = parse_scene(input_file=InputStream(stream))
# Check that the float variables are ok
assert len(scene.float_variables) == 1
assert "clock" in scene.float_variables.keys()
assert scene.float_variables["clock"] == 150.0
# Check that the materials are ok
assert len(scene.materials) == 3
assert "sphere_material" in scene.materials
assert "sky_material" in scene.materials
assert "ground_material" in scene.materials
sphere_material = scene.materials["sphere_material"]
sky_material = scene.materials["sky_material"]
ground_material = scene.materials["ground_material"]
assert isinstance(sky_material.brdf, DiffuseBRDF)
assert isinstance(sky_material.brdf.pigment, UniformPigment)
assert sky_material.brdf.pigment.color.is_close(Color(0, 0, 0))
assert isinstance(ground_material.brdf, DiffuseBRDF)
assert isinstance(ground_material.brdf.pigment, CheckeredPigment)
assert ground_material.brdf.pigment.color1.is_close(
Color(0.3, 0.5, 0.1))
assert ground_material.brdf.pigment.color2.is_close(
Color(0.1, 0.2, 0.5))
assert ground_material.brdf.pigment.num_of_steps == 4
assert isinstance(sphere_material.brdf, SpecularBRDF)
assert isinstance(sphere_material.brdf.pigment, UniformPigment)
assert sphere_material.brdf.pigment.color.is_close(Color(
0.5, 0.5, 0.5))
assert isinstance(sky_material.emitted_radiance, UniformPigment)
assert sky_material.emitted_radiance.color.is_close(
Color(0.7, 0.5, 1.0))
assert isinstance(ground_material.emitted_radiance, UniformPigment)
assert ground_material.emitted_radiance.color.is_close(Color(0, 0, 0))
assert isinstance(sphere_material.emitted_radiance, UniformPigment)
assert sphere_material.emitted_radiance.color.is_close(Color(0, 0, 0))
# Check that the shapes are ok
assert len(scene.world.shapes) == 3
assert isinstance(scene.world.shapes[0], Plane)
assert scene.world.shapes[0].transformation.is_close(
translation(Vec(0, 0, 100)) * rotation_y(150.0))
assert isinstance(scene.world.shapes[1], Plane)
assert scene.world.shapes[1].transformation.is_close(Transformation())
assert isinstance(scene.world.shapes[2], Sphere)
assert scene.world.shapes[2].transformation.is_close(
translation(Vec(0, 0, 1)))
# Check that the camera is ok
assert isinstance(scene.camera, PerspectiveCamera)
assert scene.camera.transformation.is_close(
rotation_z(30) * translation(Vec(-4, 0, 1)))
assert pytest.approx(1.0) == scene.camera.aspect_ratio
assert pytest.approx(2.0) == scene.camera.screen_distance