def test_translation_does_not_affect_vectors(self):
transform = translation(5, -3, 2)
vector = Coordinates.vector(-3, 4, 5)
result = transform * vector
assert result == vector
def test_multiplying_translation_matrix(self):
transform = translation(5, -3, 2)
point = Coordinates.point(-3, 4, 5)
result = transform * point
assert result == Coordinates.point(2, 1, 7)
def test_multiplying_by_inverse_of_translation_matrix(self):
transform = translation(5, -3, 2)
inverse = transform.inverse()
point = Coordinates.point(-3, 4, 5)
result = inverse * point
assert result == Coordinates.point(-8, 7, 3)
def test_chaining_transformations_must_be_applied_in_reverse_order(self):
point = Coordinates.point(1, 0, 1)
rotate = rotation_x(radians(90))
scale = scaling(5, 5, 5)
translate = translation(10, 5, 7)
transforms = translate * scale * rotate
result = transforms * point
assert result == Coordinates.point(15, 0, 7)
def test_individual_transformations_are_applied_in_sequence(self):
point = Coordinates.point(1, 0, 1)
rotate = rotation_x(radians(90))
scale = scaling(5, 5, 5)
translate = translation(10, 5, 7)
rotated_point = rotate * point
scaled_point = scale * rotated_point
translated_point = translate * scaled_point
assert rounded(rotated_point) == rounded(Coordinates.point(1, -1, 0))
assert rounded(scaled_point) == rounded(Coordinates.point(5, -5, 0))
assert translated_point == Coordinates.point(15, 0, 7)
from math import radians
from drawing import Canvas
from drawing.formats import PPMFormat
from drawing.transformations import translation, rotation_z, rotation_y, rotation_x
from data_structures import Coordinates, Color
width = 900
height = 900
canvas = Canvas(width, height)
degrees_of_rotations = 360 / 12
radius = (height / 2) * 0.8
point = Coordinates.point(0, 0, 0)
translate = translation(width / 2, height / 2, 0)
for i in range(12):
colors = [Color(1, 0, 0), Color(0, 1, 0), Color(0, 0, 1)]
degrees = i * degrees_of_rotations
print(f"degrees: {degrees}")
rotate = rotation_z(radians(degrees))
rotated_point = rotate * (translate * point)
print(
f"rotated_point: {rotated_point.x} {rotated_point.y} {rotated_point.z}"
)
canvas.write_pixel(int(rotated_point.x), int(rotated_point.y),
colors[i % 3])