Function solve_constraint

pub fn solve_constraint<C: XpbdConstraint<ENTITY_COUNT> + Component, const ENTITY_COUNT: usize>(
    commands: Commands<'_, '_>,
    bodies: Query<'_, '_, RigidBodyQuery, Without<RigidBodyDisabled>>,
    constraints: Query<'_, '_, &mut C, (Without<RigidBody>, Without<JointDisabled>)>,
    time: Res<'_, Time>,
)

Iterates through the XPBD constraints of a given type and solves them. Sleeping bodies are woken up when active bodies interact with them in a constraint.

Note that this system only works for constraints that are modeled as entities. If you store constraints in a resource, you must create your own system for solving them.

User Constraints

To create a new constraint, implement XpbdConstraint for a component, get the SubstepSchedule and add this system into the SubstepSolverSet::SolveUserConstraints set. You must provide the number of entities in the constraint using generics.

It should look something like this:

let substeps = app
    .get_schedule_mut(SubstepSchedule)
    .expect("add SubstepSchedule first");

substeps.add_systems(
    solve_constraint::<YourConstraint, ENTITY_COUNT>
        .in_set(SubstepSolverSet::SolveUserConstraints),
);