planck-js

# Class: RopeJoint A rope joint enforces a maximum distance between two points on two bodies. It has no other effect. Warning: if you attempt to change the maximum length during the simulation you will get some non-physical behavior. A model that would allow you to dynamically modify the length would have some sponginess, so I chose not to implement it that way. See [DistanceJoint](/api/classes/DistanceJoint) if you want to dynamically control length. ## Extends - [`Joint`](/api/classes/Joint) ## Constructors ### new RopeJoint() > **new RopeJoint**(`def`): [`RopeJoint`](/api/classes/RopeJoint) #### Parameters • **def**: [`RopeJointDef`](/api/interfaces/RopeJointDef) #### Returns [`RopeJoint`](/api/classes/RopeJoint) #### Overrides [`Joint`](/api/classes/Joint).[`constructor`](/api/classes/Joint#constructors) ### new RopeJoint() > **new RopeJoint**(`def`, `bodyA`, `bodyB`, `anchor`?): [`RopeJoint`](/api/classes/RopeJoint) #### Parameters • **def**: [`RopeJointOpt`](/api/interfaces/RopeJointOpt) • **bodyA**: [`Body`](/api/classes/Body) • **bodyB**: [`Body`](/api/classes/Body) • **anchor?**: [`Vec2Value`](/api/interfaces/Vec2Value) #### Returns [`RopeJoint`](/api/classes/RopeJoint) #### Overrides [`Joint`](/api/classes/Joint).[`constructor`](/api/classes/Joint#constructors) ## Properties ### style > **style**: [`Style`](/api/interfaces/Style) = `{}` Styling for dev-tools. #### Inherited from [`Joint`](/api/classes/Joint).[`style`](/api/classes/Joint#style) *** ### TYPE > `static` **TYPE**: `"rope-joint"` ## Methods ### getAnchorA() > **getAnchorA**(): [`Vec2`](/api/classes/Vec2) Get the anchor point on bodyA in world coordinates. #### Returns [`Vec2`](/api/classes/Vec2) #### Overrides [`Joint`](/api/classes/Joint).[`getAnchorA`](/api/classes/Joint#getanchora) *** ### getAnchorB() > **getAnchorB**(): [`Vec2`](/api/classes/Vec2) Get the anchor point on bodyB in world coordinates. #### Returns [`Vec2`](/api/classes/Vec2) #### Overrides [`Joint`](/api/classes/Joint).[`getAnchorB`](/api/classes/Joint#getanchorb) *** ### getBodyA() > **getBodyA**(): [`Body`](/api/classes/Body) Get the first body attached to this joint. #### Returns [`Body`](/api/classes/Body) #### Inherited from [`Joint`](/api/classes/Joint).[`getBodyA`](/api/classes/Joint#getbodya) *** ### getBodyB() > **getBodyB**(): [`Body`](/api/classes/Body) Get the second body attached to this joint. #### Returns [`Body`](/api/classes/Body) #### Inherited from [`Joint`](/api/classes/Joint).[`getBodyB`](/api/classes/Joint#getbodyb) *** ### getCollideConnected() > **getCollideConnected**(): `boolean` Get collide connected. Note: modifying the collide connect flag won't work correctly because the flag is only checked when fixture AABBs begin to overlap. #### Returns `boolean` #### Inherited from [`Joint`](/api/classes/Joint).[`getCollideConnected`](/api/classes/Joint#getcollideconnected) *** ### getLimitState() > **getLimitState**(): `number` #### Returns `number` *** ### getLocalAnchorA() > **getLocalAnchorA**(): [`Vec2`](/api/classes/Vec2) The local anchor point relative to bodyA's origin. #### Returns [`Vec2`](/api/classes/Vec2) *** ### getLocalAnchorB() > **getLocalAnchorB**(): [`Vec2`](/api/classes/Vec2) The local anchor point relative to bodyB's origin. #### Returns [`Vec2`](/api/classes/Vec2) *** ### getMaxLength() > **getMaxLength**(): `number` Get the maximum length of the rope. #### Returns `number` *** ### getNext() > **getNext**(): [`Joint`](/api/classes/Joint) Get the next joint the world joint list. #### Returns [`Joint`](/api/classes/Joint) #### Inherited from [`Joint`](/api/classes/Joint).[`getNext`](/api/classes/Joint#getnext) *** ### getReactionForce() > **getReactionForce**(`inv_dt`): [`Vec2`](/api/classes/Vec2) Get the reaction force on bodyB at the joint anchor in Newtons. #### Parameters • **inv\_dt**: `number` #### Returns [`Vec2`](/api/classes/Vec2) #### Overrides [`Joint`](/api/classes/Joint).[`getReactionForce`](/api/classes/Joint#getreactionforce) *** ### getReactionTorque() > **getReactionTorque**(`inv_dt`): `number` Get the reaction torque on bodyB in N*m. #### Parameters • **inv\_dt**: `number` #### Returns `number` #### Overrides [`Joint`](/api/classes/Joint).[`getReactionTorque`](/api/classes/Joint#getreactiontorque) *** ### getType() > **getType**(): `string` Get the type of the concrete joint. #### Returns `string` #### Inherited from [`Joint`](/api/classes/Joint).[`getType`](/api/classes/Joint#gettype) *** ### getUserData() > **getUserData**(): `unknown` #### Returns `unknown` #### Inherited from [`Joint`](/api/classes/Joint).[`getUserData`](/api/classes/Joint#getuserdata) *** ### initVelocityConstraints() > **initVelocityConstraints**(`step`): `void` #### Parameters • **step**: [`TimeStep`](/api/classes/TimeStep) #### Returns `void` #### Overrides [`Joint`](/api/classes/Joint).[`initVelocityConstraints`](/api/classes/Joint#initvelocityconstraints) *** ### isActive() > **isActive**(): `boolean` Short-cut function to determine if either body is inactive. #### Returns `boolean` #### Inherited from [`Joint`](/api/classes/Joint).[`isActive`](/api/classes/Joint#isactive) *** ### setMaxLength() > **setMaxLength**(`length`): `void` Set the maximum length of the rope. #### Parameters • **length**: `number` #### Returns `void` *** ### setUserData() > **setUserData**(`data`): `void` #### Parameters • **data**: `unknown` #### Returns `void` #### Inherited from [`Joint`](/api/classes/Joint).[`setUserData`](/api/classes/Joint#setuserdata) *** ### shiftOrigin() > **shiftOrigin**(`newOrigin`): `void` Shift the origin for any points stored in world coordinates. #### Parameters • **newOrigin**: [`Vec2Value`](/api/interfaces/Vec2Value) #### Returns `void` #### Inherited from [`Joint`](/api/classes/Joint).[`shiftOrigin`](/api/classes/Joint#shiftorigin) *** ### solvePositionConstraints() > **solvePositionConstraints**(`step`): `boolean` This returns true if the position errors are within tolerance. #### Parameters • **step**: [`TimeStep`](/api/classes/TimeStep) #### Returns `boolean` #### Overrides [`Joint`](/api/classes/Joint).[`solvePositionConstraints`](/api/classes/Joint#solvepositionconstraints) *** ### solveVelocityConstraints() > **solveVelocityConstraints**(`step`): `void` #### Parameters • **step**: [`TimeStep`](/api/classes/TimeStep) #### Returns `void` #### Overrides [`Joint`](/api/classes/Joint).[`solveVelocityConstraints`](/api/classes/Joint#solvevelocityconstraints)