def test_for_very_short_line_segments(self, start, delta):
path = Path((start, 0, 0))
path.line_to((start + delta, 0, 0))
path = lines_to_curve4(path)
assert len(path) == 1
assert path[0].type == Command.CURVE4_TO
assert len(list(path.flattening(1))) > 3
def test_which_length_is_too_short_to_create_a_curve(self, start, delta):
path = Path((start, 0, 0))
path.line_to((start + delta, 0, 0))
path = lines_to_curve4(path)
assert len(path) == 1
assert (
path[0].type == Command.LINE_TO
), "should not remove a single line segment representing a point"
assert len(list(path.flattening(1))) == 2
def test_line_to_curve_creates_a_linear_segment(self, func):
v1, v2 = 1, 2
path = Path(start=(v1, v1, v1))
path.line_to((v2, v2, v2))
path = func(path)
vertices = list(path.flattening(1))
assert len(vertices) > 2
assert all([
math.isclose(v.x, v.y) and math.isclose(v.x, v.z) for v in vertices
]), "all vertices have to be located along a line (x == y == z)"
def draw_path(self, path: Path, properties: Properties) -> None:
""" Draw an outline path (connected string of line segments and Bezier
curves).
The :meth:`draw_path` implementation is a fall-back implementation
which approximates Bezier curves by flattening as line segments.
Backends can override this method if better path drawing functionality
is available for that backend.
"""
if len(path):
vertices = iter(
path.flattening(distance=self.max_flattening_distance))
prev = next(vertices)
for vertex in vertices:
self.draw_line(prev, vertex, properties)
prev = vertex
