VDampedRotarySpring¶

Qualified name: manim\_pymunk.constraints.VDampedRotarySpring

class VDampedRotarySpring(a_mob, b_mob, rest_angle=0.0, stiffness=10.0, damping=1.0, arc_indicator_class=<class 'manim.mobject.geometry.arc.Arc'>, arc_indicator_config={'color': ManimColor('#FC6255'), 'radius': 0.1, 'stroke_width': 4}, connect_line_class=None, connect_line_config={'color': ManimColor('#F7D96F'), 'stroke_width': 2}, **kwargs)[source]¶

Bases: VConstraint

A rotational spring connection is created between the two rigid bodies. When the actual relative angle deviates from the target angle, the spring torque pulls it back; the damping torque dampens the oscillation.

Parameters¶

a_mob: The first Mobject to be connected. Typically acts as the pivot point or one of the bodies under physical influence.
b_mob: The second Mobject to be connected. It is linked to a_mob via a physical constraint such as a spring or hinge.
rest_angle: The equilibrium angle (in radians). The target angle between the two objects when the system is at rest and no external forces are applied.
stiffness: The spring constant (elasticity). A higher value increases the restorative force toward the rest_angle, making the spring feel “stiffer.”
damping: The damping coefficient. Used to simulate energy dissipation (like friction or air resistance). Higher values cause oscillations to decay faster.
arc_indicator_class: The class used to visualize the angle (defaults to Arc). If set to None, no angular arc will be rendered.
arc_indicator_config: A dictionary defining the visual style of the arc indicator, including radius, color, and stroke_width.
connect_line_class: The class used to draw a connecting line between the two objects (e.g., Line). Defaults to None for no visible connection.
connect_line_config: A dictionary defining the visual style of the connecting line, such as color and stroke_width.

Examples¶

Example: VDampedRotarySpringExample ¶

from manim import *

from manim_pymunk import *

class VDampedRotarySpringExample(SpaceScene):
    def construct(self):
        floor = Line(LEFT * 10, RIGHT * 10).shift(DOWN*2)

        square_1 = Square().next_to(floor, UP)
        square_2 = Square().move_to(square_1.get_center() + RIGHT * 4)

        constraint = VDampedRotarySpring(
            square_1,
            square_2,
            rest_angle=PI / 4,
            stiffness=100,
            damping=1,
        )

        self.add_static_body(floor)
        self.add_dynamic_body(square_1, square_2)
        self.add_constraints(constraint)

        self.wait(3)

from manim_pymunk import *

class VDampedRotarySpringExample(SpaceScene):
    def construct(self):
        floor = Line(LEFT * 10, RIGHT * 10).shift(DOWN*2)

        square_1 = Square().next_to(floor, UP)
        square_2 = Square().move_to(square_1.get_center() + RIGHT * 4)

        constraint = VDampedRotarySpring(
            square_1,
            square_2,
            rest_angle=PI / 4,
            stiffness=100,
            damping=1,
        )

        self.add_static_body(floor)
        self.add_dynamic_body(square_1, square_2)
        self.add_constraints(constraint)

        self.wait(3)

Methods

`install`	Initialization of physics and visualization components
`mob_updater`	Visual control updater

Attributes

`always`	Call a method on a mobject every frame.
`animate`	Used to animate the application of any method of `self`.
`animation_overrides`
`color`
`depth`	The depth of the mobject.
`fill_color`	If there are multiple colors (for gradient) this returns the first one
`height`	The height of the mobject.
`n_points_per_curve`
`sheen_factor`
`stroke_color`
`width`	The width of the mobject.

__check_data()¶: Verify the validity of constraint parameters.

_abc_impl = <_abc._abc_data object>¶

_bezier_t_values: npt.NDArray[float]¶

_original__init__(a_mob, b_mob, rest_angle=0.0, stiffness=10.0, damping=1.0, arc_indicator_class=<class 'manim.mobject.geometry.arc.Arc'>, arc_indicator_config={'color': ManimColor('#FC6255'), 'radius': 0.1, 'stroke_width': 4}, connect_line_class=None, connect_line_config={'color': ManimColor('#F7D96F'), 'stroke_width': 2}, **kwargs)¶

Initialize self. See help(type(self)) for accurate signature.

Parameters:

a_mob (Mobject)
b_mob (Mobject)
rest_angle (float)
stiffness (float)
damping (float)
arc_indicator_class (Arc | None)
arc_indicator_config (dict)
connect_line_class (Line | None)
connect_line_config (dict)

animation_overrides = {}¶

arc_a: VMobject | None¶

arc_b: VMobject | None¶

background_image: Image | str | None¶

background_stroke_color: ManimColor¶

background_stroke_opacity: float¶

background_stroke_width: float¶

cap_style: CapStyleType¶

close_new_points: bool¶

conn_line: VMobject | None¶

constraint: DampedRotarySpring | None¶

install(space)[source]¶

Initialization of physics and visualization components

Parameters:: space (Space)

joint_type: LineJointType¶

make_smooth_after_applying_functions: bool¶

mob_updater(mob, dt)[source]¶: Visual control updater

n_points_per_cubic_curve: int¶

pre_function_handle_to_anchor_scale_factor: float¶

shade_in_3d: bool¶

submobjects: list[VMobject]¶

tolerance_for_point_equality: float¶

Parameters:

a_mob (Mobject)
b_mob (Mobject)
rest_angle (float)
stiffness (float)
damping (float)
arc_indicator_class (Arc | None)
arc_indicator_config (dict)
connect_line_class (Line | None)
connect_line_config (dict)