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)
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