Struct ContactCache 

pub struct ContactCache {
    pub manifolds: Vec<ContactManifold>,
    pub max_stale_frames: u32,
    pub warm_start_factor: Fix128,
    /* private fields */
}

Contact cache: stores all active manifolds across frames

Fields

manifolds: Vec<ContactManifold>

All active manifolds

max_stale_frames: u32

Maximum stale frames before manifold is removed

warm_start_factor: Fix128

Warm starting factor (0.0 = off, 1.0 = full warm start)

Implementations

impl ContactCache

pub fn new() -> Self

Create a new contact cache

pub fn get_or_create( &mut self, pair: BodyPairKey, friction: Fix128, restitution: Fix128, ) -> &mut ContactManifold

Find or create manifold for a body pair

Panics

Panics if the internal manifold Vec is empty after a push (should never happen).

pub fn find(&self, pair: &BodyPairKey) -> Option<&ContactManifold>

Find manifold for a body pair (read-only)

manifolds is pub, so an external clear()/retain()/remove() on it can leave the private pair_index pointing past the end or at another pair’s slot; the slot is checked, so a stale index neither panics nor answers another pair.

pub fn begin_frame(&mut self)

Mark all manifolds as potentially stale (call at start of frame)

pub fn end_frame(&mut self)

Remove expired manifolds (call at end of frame)

pub fn manifold_count(&self) -> usize

Total number of active manifolds

pub fn total_contact_points(&self) -> usize

Total number of active contact points across all manifolds

pub fn clear(&mut self)

Clear all manifolds

pub fn apply_warm_start(&self, bodies: &mut [RigidBody])

Apply warm starting impulses to bodies

Pre-applies accumulated impulses from the previous frame’s solution, scaled by warm_start_factor. This dramatically improves convergence.

Trait Implementations

impl Debug for ContactCache

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

Formats the value using the given formatter.

impl Default for ContactCache

fn default() -> Self

Returns the “default value” for a type.