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Class: Fixture

A fixture is used to attach a shape to a body for collision detection. A fixture inherits its transform from its parent. Fixtures hold additional non-geometric data such as friction, collision filters, etc.

To create a new Fixture use Body.createFixture.

Properties

style

style: Style = {}

Styling for dev-tools.

Methods

createProxies()

createProxies(broadPhase, xf): void

These support body activation/deactivation.

Parameters

broadPhase

BroadPhase

xf

TransformValue

Returns

void


destroyProxies()

destroyProxies(broadPhase): void

Parameters

broadPhase

BroadPhase

Returns

void


getAABB()

getAABB(childIndex): AABB

Get the fixture's AABB. This AABB may be enlarge and/or stale. If you need a more accurate AABB, compute it using the shape and the body transform.

Parameters

childIndex

number

Returns

AABB


getBody()

getBody(): Body

Get the parent body of this fixture. This is null if the fixture is not attached.

Returns

Body


getDensity()

getDensity(): number

Get the density of this fixture.

Returns

number


getFilterCategoryBits()

getFilterCategoryBits(): number

Returns

number


getFilterGroupIndex()

getFilterGroupIndex(): number

Returns

number


getFilterMaskBits()

getFilterMaskBits(): number

Returns

number


getFriction()

getFriction(): number

Get the coefficient of friction, usually in the range [0,1].

Returns

number


getMassData()

getMassData(massData): void

Get the mass data for this fixture. The mass data is based on the density and the shape. The rotational inertia is about the shape's origin. This operation may be expensive.

Parameters

massData

MassData

Returns

void


getNext()

getNext(): Fixture

Get the next fixture in the parent body's fixture list.

Returns

Fixture


getRestitution()

getRestitution(): number

Get the coefficient of restitution.

Returns

number


getShape()

getShape(): Shape

Get the child shape. You can modify the child shape, however you should not change the number of vertices because this will crash some collision caching mechanisms. Manipulating the shape may lead to non-physical behavior.

Returns

Shape


getType()

getType(): ShapeType

Get the type of the child shape. You can use this to down cast to the concrete shape.

Returns

ShapeType


getUserData()

getUserData(): unknown

Get the user data that was assigned in the fixture definition. Use this to store your application specific data.

Returns

unknown


isSensor()

isSensor(): boolean

A sensor shape collects contact information but never generates a collision response.

Returns

boolean


rayCast()

rayCast(output, input, childIndex): boolean

Cast a ray against this shape.

Parameters

output

RayCastOutput

input

RayCastInput

childIndex

number

Returns

boolean


refilter()

refilter(): void

Call this if you want to establish collision that was previously disabled by ContactFilter.

Returns

void


setDensity()

setDensity(density): void

Set the density of this fixture. This will not automatically adjust the mass of the body. You must call Body.resetMassData to update the body's mass.

Parameters

density

number

Returns

void


setFilterCategoryBits()

setFilterCategoryBits(categoryBits): void

Parameters

categoryBits

number

Returns

void


setFilterData()

setFilterData(filter): void

Set the contact filtering data. This will not update contacts until the next time step when either parent body is active and awake. This automatically calls refilter.

Parameters

filter
categoryBits

number

groupIndex

number

maskBits

number

Returns

void


setFilterGroupIndex()

setFilterGroupIndex(groupIndex): void

Parameters

groupIndex

number

Returns

void


setFilterMaskBits()

setFilterMaskBits(maskBits): void

Parameters

maskBits

number

Returns

void


setFriction()

setFriction(friction): void

Set the coefficient of friction. This will not change the friction of existing contacts.

Parameters

friction

number

Returns

void


setRestitution()

setRestitution(restitution): void

Set the coefficient of restitution. This will not change the restitution of existing contacts.

Parameters

restitution

number

Returns

void


setSensor()

setSensor(sensor): void

Set if this fixture is a sensor.

Parameters

sensor

boolean

Returns

void


setUserData()

setUserData(data): void

Set the user data. Use this to store your application specific data.

Parameters

data

unknown

Returns

void


shouldCollide()

shouldCollide(that): boolean

Implement this method to provide collision filtering, if you want finer control over contact creation.

Return true if contact calculations should be performed between these two fixtures.

Warning: for performance reasons this is only called when the AABBs begin to overlap.

Parameters

that

Fixture

Returns

boolean


synchronize()

synchronize(broadPhase, xf1, xf2): void

Updates this fixture proxy in broad-phase (with combined AABB of current and next transformation).

Parameters

broadPhase

BroadPhase

xf1

TransformValue

xf2

TransformValue

Returns

void


testPoint()

testPoint(p): boolean

Test a point in world coordinates for containment in this fixture.

Parameters

p

Vec2Value

Returns

boolean