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use na::{self, Real};
/// Parameters for a time-step of the physics engine.
pub struct IntegrationParameters<N: Real> {
/// The timestep (default: `1.0 / 60.0`)
pub dt: N,
/// The Error Reduction Parameter in `[0, 1]` is the proportion of
/// the positional error to be corrected at each time step (default: `0.2`).
pub erp: N,
/// Each cached impulse are multiplied by this coefficient in `[0, 1]`
/// when they are re-used to initialize the solver (default `1.0`).
pub warmstart_coeff: N,
/// Contacts at points where the involved bodies have a relative
/// velocity smaller than this threshold wont be affected by the restitution force (default: `1.0`).
pub restitution_velocity_threshold: N,
/// Ammount of penetration the engine wont attempt to correct (default: `0.001m`).
pub allowed_linear_error: N,
/// Ammount of angular drift of joint limits the engine wont
/// attempt to correct (default: `0.001rad`).
pub allowed_angular_error: N,
/// Maximum linear correction during one step of the non-linear position solver (default: `100.0`).
pub max_linear_correction: N,
/// Maximum angular correction during one step of the non-linear position solver (default: `0.2`).
pub max_angular_correction: N,
/// Maximum nonlinera SOR-prox scaling parameter when the constraint
/// correction direction is close to the kernel of the involved multibody's
/// jacobian (default: `0.2`).
pub max_stabilization_multiplier: N,
/// Maximum number of iterations performed by the velocity constraints solver.
pub max_velocity_iterations: usize,
/// Maximum number of iterations performed by the position-based constraints solver.
pub max_position_iterations: usize,
}
impl<N: Real> IntegrationParameters<N> {
/// Creates a set of integration parameters with the given values.
pub fn new(
dt: N,
erp: N,
warmstart_coeff: N,
restitution_velocity_threshold: N,
allowed_linear_error: N,
allowed_angular_error: N,
max_linear_correction: N,
max_angular_correction: N,
max_stabilization_multiplier: N,
max_velocity_iterations: usize,
max_position_iterations: usize,
) -> Self {
IntegrationParameters {
dt,
erp,
warmstart_coeff,
restitution_velocity_threshold,
allowed_linear_error,
allowed_angular_error,
max_linear_correction,
max_angular_correction,
max_stabilization_multiplier,
max_velocity_iterations,
max_position_iterations,
}
}
}
impl<N: Real> Default for IntegrationParameters<N> {
fn default() -> Self {
Self::new(
na::convert(1.0 / 60.0),
na::convert(0.2),
na::convert(1.0),
na::convert(1.0),
na::convert(0.001),
na::convert(0.001),
na::convert(100.0),
na::convert(0.2),
na::convert(0.2),
8,
3,
)
}
}