nape.constraint.PulleyJoint

PulleyJoint limiting the weighted sum of distances between 2 pairs of 4 local anchor points of Bodies.

The equation for this constraint could be written like:

jointMin <= distance(body2.localPointToWorld(anchor2), body1.localPointToWorld(anchor1))
+ ratio * distance(body4.localPointToWorld(anchor4), body3.localPointToWorld(anchor3)) <= jointMax

This joint is not designed to work when either of these pairs achieves a distance of 0, it will still work but may not be entirely ideal. !1*

* This constraint can be used in a full 4-body set up, or a 3-body set up or a 2-body set up permitting any arrangement as long as body1 != body2 and body3 != body4

Constructor

`@:value({ ratio : 1.0 })new(body1:Null<Body>, body2:Null<Body>, body3:Null<Body>, body4:Null<Body>, anchor1:Vec2, anchor2:Vec2, anchor3:Vec2, anchor4:Vec2, jointMin:Float, jointMax:Float, ratio:Float = 1.0)`

Construct a new PulleyJoint.

Parameters:

`body1`	The first body in PulleyJoint.
`body2`	The second body in PulleyJoint.
`body3`	The third body in PulleyJoint.
`body4`	The fourth body in PulleyJoint.
`anchor1`	The first local anchor for joint.
`anchor2`	The second local anchor for joint.
`anchor3`	The third local anchor for joint.
`anchor4`	The fourth local anchor for joint.
`jointMin`	The lower bound for constraint.
`jointMax`	The upper bound for constraint.
`ratio`	The ratio for constraint.

Returns:

The constructed PulleyJoint.

Variables

`anchor1:Vec2`

Anchor point on first Body.

This anchor point is defined in the local coordinate system of body1.

`anchor2:Vec2`

Anchor point on second Body.

This anchor point is defined in the local coordinate system of body2.

`anchor3:Vec2`

Anchor point on third Body.

This anchor point is defined in the local coordinate system of body3.

`anchor4:Vec2`

Anchor point on fourth Body.

This anchor point is defined in the local coordinate system of body4.

`body1:Null<Body>`

First Body in constraint.

This value may be null, but trying to simulate the constraint whilst this body is null will result in an error.

`body2:Null<Body>`

Second Body in constraint.

This value may be null, but trying to simulate the constraint whilst this body is null will result in an error.

`body3:Null<Body>`

Third Body in constraint.

This value may be null, but trying to simulate the constraint whilst this body is null will result in an error.

`body4:Null<Body>`

Fourth Body in constraint.

This value may be null, but trying to simulate the constraint whilst this body is null will result in an error.

`jointMax:Float`

Upper bound for constraint.

This value must be greater than or equal to jointMin.

`jointMin:Float`

Lower bound for constraint.

This value must be less than or equal to jointMax, and greater equal to 0.

`ratio:Float`

Ratio property of constraint.

`@:value(null)zpp_inner_zn:ZPP_PulleyJoint = null`

@private

Methods

`bodyImpulse(body:Body):Vec3`

@inheritDoc

`impulse():MatMN`

@inheritDoc

For this constraint, the MatMN will be 1x1.

`inlineisSlack():Bool`

Determine if constraint is slack.

This constraint is slack if the positional error is within the bounds of (jointMin, jointMax).

Returns:

True if positional error of constraint is between the limits indicating that the constraint is not doing any work.

Throws:

`#`	If any of the bodies is null.

`visitBodies(lambda:Body ‑> Void):Void`

@inheritDoc

Inherited Variables

Defined by Constraint

`active:Bool`

Whether this constraint is active or not.

Setting a constraint to be no longer active is a useful way of temporarigly disabling a constraint without having to remove it from a Space.

`breakUnderError:Bool`

Whether constraint will break once maxError is reached.

This property effects both stiff and non-stiff constraints.

`breakUnderForce:Bool`

Whether constraint will break once maxForce is reached.

This property effects both stiff and non-stiff constraints, though for the same reasons as those of maxForce, does not make much sense to be used in stiff constraints.

`read onlycbTypes:CbTypeList`

Set of CbTypes for this constraints for callbacks.

This value cannot at present be set, but can be modified.

`compound:Null<Compound>`

Compound this Constraints belong to.

If this constraint is in a Space or another Compound and you change its compound, then it will be removed from that Space or Compound.

`damping:Float`

Damping ratio of elastic properties of constraint.

This property only has an effect when constraint is not stiff.

This value corresponds to in the ideal situation, the damping ratio of the constraints oscillations with 1 corresponding to a total dampening, and values greater than one being over-dampening.

This value must be zero or positive.

`@:value(true)debugDraw:Bool = true`

Set to disable debug drawing/

When true, this Constraint will not be drawn during debug draw operations unless specifically given as argument to Debug draw() method.

`frequency:Float`

Frequency of elastic properties of constraint.

This property only has an effect when constraint is not stiff.

This value corresponds to in an ideal situation, the number of spring like oscillations the constraint will make per second.

This value must be strictly positive (0 not allowed).

`ignore:Bool`

Whether interactions between related Bodys will be ignored.

If true, then the Bodys related to this constraint will not be permitted to interact in anyway, including callbacks.

`read onlyisSleeping:Bool`

Whether this constraint is sleeping or not.

This property is only defined if the constraint is inside of a Space and is active, otherwise an error will be thrown should you access this property.

This value is immutable, In Nape you do not ever need to manually wake up a Constraint. It will always be done automatically without error.

To manually put a Constraint to sleep is against the very nature of Nape API and so is excluded from the core of Nape. If you really want to do this you should make use of the nape-hacks module.

`maxError:Float`

The maximum amount of error this constraint is allowed to use.

For stiff constraints, this value only serves to work in conjunction with breakUnderError to permit breaking of the constraint.

For non-stiff constraints, this value will also effect how the constraint behaves when breakUnderError is false by restricting the amount of error that will be resolved; this will not work for stiff constraints.

`maxForce:Float`

The maximum amount of force this constraint is allowed to use.

This value, whilst still used in a stiff constraint will not work as you might hope for; since a stiff constraint resolves positional error without using impulses, the maxForce will not have any effect on how positional errors are resolved.

This value must be zero or positive.

`removeOnBreak:Bool`

Whether constraint will be removed when it breaks.

If true, then when constraint is broken it will be removed from the Space. Otherwise it will simple be made inactive.

`space:Null<Space>`

Space this constraint is inside of.

Whether this constraint is directly in a Space, or part of a Compound which is inside of a space, this value will be equal to that Space.

If this constraint is inside of a Compound, then you cannot modify its Space as the constraint belongs to that Compound.

`stiff:Bool`

Whether constraint is stiff, or elastic.

A stiff constraint has its positional error resolved directly as with contact penetrations. This is generally a more stable way of solving positional errors but has a side-effect that for example changing the pivot point on a constraint used for mouse control will not cause the objects to swing as the positional error is solved without effecting the velocity of the object which may not be wanted.

If false, then the positional error of the constraint will be resolved in an elastic way using changes in velocity.

`read onlyuserData:Dynamic<Dynamic>`

Dynamic object for user to store additional data.

This object cannot be set, only its dynamically created properties may be set. In AS3 the type of this property is &#42

This object will be lazily constructed so that until accessed for the first time, will be null internally.

`zpp_inner:ZPP_Constraint`

@private

final class PulleyJoint

package nape.constraint

extends Constraint

Constructor

@:value({ ratio : 1.0 })new(body1:Null<Body>, body2:Null<Body>, body3:Null<Body>, body4:Null<Body>, anchor1:Vec2, anchor2:Vec2, anchor3:Vec2, anchor4:Vec2, jointMin:Float, jointMax:Float, ratio:Float = 1.0)

Variables

anchor1:Vec2

anchor2:Vec2

anchor3:Vec2

anchor4:Vec2

body1:Null<Body>

body2:Null<Body>

body3:Null<Body>

body4:Null<Body>

jointMax:Float

jointMin:Float

ratio:Float

@:value(null)zpp_inner_zn:ZPP_PulleyJoint = null

Methods

bodyImpulse(body:Body):Vec3

impulse():MatMN

inlineisSlack():Bool

visitBodies(lambda:Body ‑> Void):Void

Inherited Variables

Defined by Constraint

active:Bool

breakUnderError:Bool

breakUnderForce:Bool

read onlycbTypes:CbTypeList

compound:Null<Compound>

damping:Float

@:value(true)debugDraw:Bool = true

frequency:Float

ignore:Bool

read onlyisSleeping:Bool

maxError:Float

maxForce:Float

removeOnBreak:Bool

space:Null<Space>

stiff:Bool

read onlyuserData:Dynamic<Dynamic>

zpp_inner:ZPP_Constraint

Inherited Methods

Defined by Constraint

copy():Constraint

@:keeptoString():String

`@:value({ ratio : 1.0 })new(body1:Null<Body>, body2:Null<Body>, body3:Null<Body>, body4:Null<Body>, anchor1:Vec2, anchor2:Vec2, anchor3:Vec2, anchor4:Vec2, jointMin:Float, jointMax:Float, ratio:Float = 1.0)`

`anchor1:Vec2`

`anchor2:Vec2`

`anchor3:Vec2`

`anchor4:Vec2`

`body1:Null<Body>`

`body2:Null<Body>`

`body3:Null<Body>`

`body4:Null<Body>`

`jointMax:Float`

`jointMin:Float`

`ratio:Float`

`@:value(null)zpp_inner_zn:ZPP_PulleyJoint = null`

`bodyImpulse(body:Body):Vec3`

`impulse():MatMN`

`inlineisSlack():Bool`

`visitBodies(lambda:Body ‑> Void):Void`

`active:Bool`

`breakUnderError:Bool`

`breakUnderForce:Bool`

`read onlycbTypes:CbTypeList`

`compound:Null<Compound>`

`damping:Float`

`@:value(true)debugDraw:Bool = true`

`frequency:Float`

`ignore:Bool`

`read onlyisSleeping:Bool`

`maxError:Float`

`maxForce:Float`

`removeOnBreak:Bool`

`space:Null<Space>`

`stiff:Bool`

`read onlyuserData:Dynamic<Dynamic>`

`zpp_inner:ZPP_Constraint`

`copy():Constraint`

`@:keeptoString():String`