def test_plane_from_points_order(self):
points = np.array([
[1, 0, 0],
[0, math.sqrt(1.25), 0],
[-1, 0, 0],
])
plane = Plane.from_points(*points)
expected_v = np.array([0, 0, 1])
np.testing.assert_array_equal(plane.normal, expected_v)
def test_plane_from_points(self):
points = np.array([
[1, 1, 1],
[-1, 1, 0],
[2, 0, 3],
])
plane = Plane.from_points(*points)
a, b, c, d = plane.equation
plane_equation_test = [a * x + b * y + c * z + d for x, y, z in points]
np.testing.assert_array_equal(plane_equation_test, [0, 0, 0])
projected_points = [plane.project_point(p) for p in points]
np.testing.assert_array_almost_equal(projected_points, points)
def create_triangular_prism(p1, p2, p3, height):
'''
Return a Mesh which is a triangular prism whose base is the triangle
p1, p2, p3. If the vertices are oriented in a counterclockwise
direction, the prism extends from behind them.
'''
from blmath.geometry import Plane
base_plane = Plane.from_points(p1, p2, p3)
lower_base_to_upper_base = height * -base_plane.normal # pylint: disable=invalid-unary-operand-type
vertices = np.vstack(([p1, p2, p3], [p1, p2, p3] + lower_base_to_upper_base))
faces = np.array([
[0, 1, 2], # base
[0, 3, 4], [0, 4, 1], # side 0, 3, 4, 1
[1, 4, 5], [1, 5, 2], # side 1, 4, 5, 2
[2, 5, 3], [2, 3, 0], # side 2, 5, 3, 0
[5, 4, 3], # base
])
return Mesh(v=vertices, f=faces)