def point_at_angle(self, angle: float):
"""Returns the position of a point on the circle.
Parameters
----------
angle
The angle of the point along the circle in radians.
Returns
-------
:class:`numpy.ndarray`
The location of the point along the circle's circumference.
Examples
--------
.. manim:: PointAtAngleExample
:save_last_frame:
class PointAtAngleExample(Scene):
def construct(self):
circle = Circle(radius=2.0)
p1 = circle.point_at_angle(PI/2)
p2 = circle.point_at_angle(270*DEGREES)
s1 = Square(side_length=0.25).move_to(p1)
s2 = Square(side_length=0.25).move_to(p2)
self.add(circle, s1, s2)
"""
start_angle = angle_of_vector(self.points[0] - self.get_center())
proportion = (angle - start_angle) / TAU
proportion -= math.floor(proportion)
return self.point_from_proportion(proportion)
def tip_angle(self):
r"""The angle of the arrow tip.
Examples
--------
::
>>> from manim import Arrow
>>> arrow = Arrow(np.array([0, 0, 0]), np.array([1, 1, 0]), buff=0)
>>> round(arrow.tip.tip_angle, 5) == round(PI/4, 5)
True
"""
return angle_of_vector(self.vector)
def __init__(
self,
line1: Line,
line2: Line,
radius: float = None,
quadrant=(1, 1),
other_angle: bool = False,
dot=False,
dot_radius=None,
dot_distance=0.55,
dot_color=WHITE,
elbow=False,
**kwargs,
):
super().__init__(**kwargs)
self.lines = (line1, line2)
self.quadrant = quadrant
self.dot_distance = dot_distance
self.elbow = elbow
inter = line_intersection(
[line1.get_start(), line1.get_end()],
[line2.get_start(), line2.get_end()],
)
if radius is None:
if quadrant[0] == 1:
dist_1 = np.linalg.norm(line1.get_end() - inter)
else:
dist_1 = np.linalg.norm(line1.get_start() - inter)
if quadrant[1] == 1:
dist_2 = np.linalg.norm(line2.get_end() - inter)
else:
dist_2 = np.linalg.norm(line2.get_start() - inter)
if np.minimum(dist_1, dist_2) < 0.6:
radius = (2 / 3) * np.minimum(dist_1, dist_2)
else:
radius = 0.4
else:
self.radius = radius
anchor_angle_1 = inter + quadrant[0] * radius * line1.get_unit_vector()
anchor_angle_2 = inter + quadrant[1] * radius * line2.get_unit_vector()
if elbow:
anchor_middle = (inter +
quadrant[0] * radius * line1.get_unit_vector() +
quadrant[1] * radius * line2.get_unit_vector())
angle_mobject = Elbow(**kwargs)
angle_mobject.set_points_as_corners(
[anchor_angle_1, anchor_middle, anchor_angle_2], )
else:
angle_1 = angle_of_vector(anchor_angle_1 - inter)
angle_2 = angle_of_vector(anchor_angle_2 - inter)
if not other_angle:
start_angle = angle_1
if angle_2 > angle_1:
angle_fin = angle_2 - angle_1
else:
angle_fin = 2 * np.pi - (angle_1 - angle_2)
else:
start_angle = angle_1
if angle_2 < angle_1:
angle_fin = -angle_1 + angle_2
else:
angle_fin = -2 * np.pi + (angle_2 - angle_1)
self.angle_value = angle_fin
angle_mobject = Arc(
radius=radius,
angle=self.angle_value,
start_angle=start_angle,
arc_center=inter,
**kwargs,
)
if dot:
if dot_radius is None:
dot_radius = radius / 10
else:
self.dot_radius = dot_radius
right_dot = Dot(ORIGIN, radius=dot_radius, color=dot_color)
dot_anchor = (
inter + (angle_mobject.get_center() - inter) /
np.linalg.norm(angle_mobject.get_center() - inter) *
radius * dot_distance)
right_dot.move_to(dot_anchor)
self.add(right_dot)
self.set_points(angle_mobject.points)
def get_angle(self):
return angle_of_vector(self.get_vector())
def stop_angle(self):
return angle_of_vector(self.points[-1] - self.get_arc_center()) % TAU