VDampedSpring¶

Qualified name: manim\_pymunk.constraints.VDampedSpring

class VDampedSpring(a_mob, b_mob, anchor_a_local=array([0., 0., 0.]), anchor_b_local=array([0., 0., 0.]), rest_length=1.0, stiffness=100.0, damping=10.0, mob_a_appearance=Dot, mob_b_appearance=Dot, connect_line_class=<class 'manim_pymunk.custom_mobjects.v_spring.VSpring'>, connect_line_config={'color': ManimColor('#F7D96F'), 'stroke_width': 2}, **kwargs)[source]¶

Bases: VConstraint

A damped spring connection is created between two rigid bodies. The spring applies a restorative force proportional to the displacement from its rest length, while the damping simulates energy loss to suppress oscillations.

Parameters¶

a_mob: The first Mobject to be connected. Acts as one of the anchor points for the spring.
b_mob: The second Mobject to be connected. Linked to a_mob via the physical spring constraint.
anchor_a_local: The local anchor point on a_mob where the spring is attached, relative to the Mobject’s center.
anchor_b_local: The local anchor point on b_mob where the spring is attached, relative to the Mobject’s center.
rest_length: The equilibrium length of the spring. When the distance between anchors equals this value, the spring exerts no force.
stiffness: The spring constant $k$ (Young’s modulus). Determines how strongly the spring pulls or pushes to return to rest_length.
damping: The damping coefficient $c$. Used to simulate viscous friction, causing the kinetic energy of the system to dissipate over time.
mob_a_appearance: The Mobject used to visually represent the anchor point on a_mob (e.g., a Dot).
mob_b_appearance: The Mobject used to visually represent the anchor point on b_mob (e.g., a Dot).
connect_line_class: The class used to visualize the spring body (defaults to VSpring). If set to None, the spring connection will be invisible.
connect_line_config: A dictionary defining the visual style of the connect_line_class, such as color and stroke_width.

Examples¶

Example: VDampedSpringExample ¶

from manim import *

from manim_pymunk import *

class VDampedSpringExample(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() + UP * 4)

        constraint = VDampedSpring(
            square_1,
            square_2,
            rest_length=3,
            stiffness=100,
            damping=10,
        )

        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 VDampedSpringExample(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() + UP * 4)

        constraint = VDampedSpring(
            square_1,
            square_2,
            rest_length=3,
            stiffness=100,
            damping=10,
        )

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

        self.wait(3)

Methods

`install`	Verify the validity of constraint parameters.
`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.

_abc_impl = <_abc._abc_data object>¶

_bezier_t_values: npt.NDArray[float]¶

_original__init__(a_mob, b_mob, anchor_a_local=array([0., 0., 0.]), anchor_b_local=array([0., 0., 0.]), rest_length=1.0, stiffness=100.0, damping=10.0, mob_a_appearance=Dot, mob_b_appearance=Dot, connect_line_class=<class 'manim_pymunk.custom_mobjects.v_spring.VSpring'>, 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)
anchor_a_local (list[float, float, float])
anchor_b_local (list[float, float, float])
rest_length (float)
stiffness (float)
damping (float)
mob_a_appearance (Mobject)
mob_b_appearance (Mobject)
connect_line_class (Line | None)
connect_line_config (dict)

animation_overrides = {}¶

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: DampedSpring | None¶

install(space)[source]¶

Verify the validity of constraint parameters.

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)
anchor_a_local (list[float, float, float])
anchor_b_local (list[float, float, float])
rest_length (float)
stiffness (float)
damping (float)
mob_a_appearance (Mobject)
mob_b_appearance (Mobject)
connect_line_class (Line | None)
connect_line_config (dict)