Struct ContactPoint

pub struct ContactPoint {
    pub anchor1: Vector,
    pub anchor2: Vector,
    pub point: Vector,
    pub penetration: Scalar,
    pub normal_impulse: Scalar,
    pub normal_speed: Scalar,
    pub warm_start_normal_impulse: Scalar,
    pub warm_start_tangent_impulse: Vector2,
    pub feature_id1: PackedFeatureId,
    pub feature_id2: PackedFeatureId,
}

Data associated with a contact point in a ContactManifold.

Fields

anchor1: Vector

The world-space contact point on the first shape relative to the center of mass.

anchor2: Vector

The world-space contact point on the second shape relative to the center of mass.

point: Vector

The contact point in world space.

This is the midpoint between the closest points on the surfaces of the two shapes.

Note that because the contact point is expressed in world space, it is subject to precision loss at large coordinates.

penetration: Scalar

The penetration depth.

Can be negative if the objects are separated and speculative collision is enabled.

normal_impulse: Scalar

The total normal impulse applied to the first body at this contact point. The unit is typically N⋅s or kg⋅m/s.

This can be used to determine how “strong” a contact is. To compute the corresponding contact force, divide the impulse by the time step.

normal_speed: Scalar

The relative velocity of the bodies at the contact point along the contact normal. If negative, the bodies are approaching. The unit is typically m/s.

This is computed before the solver, and can be used as an impact velocity to determine how “strong” the contact is in a mass-independent way.

Internally, the normal_speed is used for restitution.

warm_start_normal_impulse: Scalar

The normal impulse used to warm start the contact solver.

This corresponds to the clamped accumulated impulse from the last substep of the previous time step.

warm_start_tangent_impulse: Vector2

The frictional impulse used to warm start the contact solver.

This corresponds to the clamped accumulated impulse from the last substep of the previous time step.

feature_id1: PackedFeatureId

The contact feature ID on the first shape. This indicates the ID of the vertex, edge, or face of the contact, if one can be determined.

feature_id2: PackedFeatureId

The contact feature ID on the second shape. This indicates the ID of the vertex, edge, or face of the contact, if one can be determined.

Implementations

impl ContactPoint

pub fn new( anchor1: Vector, anchor2: Vector, world_point: Vector, penetration: Scalar, ) -> Self

Creates a new ContactPoint with the given world-space contact points relative to the centers of mass of the two shapes, the world-space contact point, and the penetration depth.

Feature IDs can be specified for the contact points using with_feature_ids.

pub fn with_feature_ids( self, id1: PackedFeatureId, id2: PackedFeatureId, ) -> Self

Sets the feature IDs of the contact points.

pub fn flip(&mut self)

Flips the contact data, swapping the points and feature IDs, and negating the impulses.

pub fn flipped(&self) -> Self

Returns a flipped copy of the contact data, swapping the points and feature IDs, and negating the impulses.

Trait Implementations

impl Clone for ContactPoint

fn clone(&self) -> ContactPoint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ContactPoint

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for ContactPoint

fn eq(&self, other: &ContactPoint) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for ContactPoint

impl StructuralPartialEq for ContactPoint