nichkara/rapier
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat: add IntegrationParameters::length_unit to adjust internal threshold based on user-defined length units

Browse Source
This commit is contained in:
Sébastien Crozet
2024-04-24 22:37:21 +02:00
committed by Sébastien Crozet
parent 6635d49c8b
commit c079452a47
10 changed files with 80 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files

54
src/dynamics/integration_parameters.rs
View File

@@ -49,12 +49,33 @@ pub struct IntegrationParameters {
/// (default `1.0`).
pub warmstart_coefficient: Real,
/// The approximate size of most dynamic objects in the scale.
///
/// This value is used internally to estimate some length-based tolerance. In particular, the
/// values [`IntegrationParametres::allowed_linear_error`],
/// [`IntegrationParametres::max_penetration_correction`],
/// [`IntegrationParametres::prediction_distance`], [`RigidBodyActivation::linear_threshold`]
/// are scaled by this value implicitly.
///
/// This value can be understood as the number of units-per-meter in your physical world compared
/// to a human-sized world in meter. For example, in a 2d game, if your typical object size is 100
/// pixels, set the `[`Self::length_unit`]` parameter to 100.0. The physics engine will interpret
/// it as if 100 pixels is equivalent to 1 meter in its various internal threshold.
/// (default `1.0`).
pub length_unit: Real,
/// Amount of penetration the engine won’t attempt to correct (default: `0.001m`).
pub allowed_linear_error: Real,
///
/// This value is implicitly scaled by [`IntegrationParameters::length_unit`].
pub normalized_allowed_linear_error: Real,
/// Maximum amount of penetration the solver will attempt to resolve in one timestep.
pub max_penetration_correction: Real,
///
/// This value is implicitly scaled by [`IntegrationParameters::length_unit`].
pub normalized_max_penetration_correction: Real,
/// The maximal distance separating two objects that will generate predictive contacts (default: `0.002m`).
pub prediction_distance: Real,
///
/// This value is implicitly scaled by [`IntegrationParameters::length_unit`].
pub normalized_prediction_distance: Real,
/// The number of solver iterations run by the constraints solver for calculating forces (default: `4`).
pub num_solver_iterations: NonZeroUsize,
/// Number of addition friction resolution iteration run during the last solver sub-step (default: `4`).
@@ -157,6 +178,22 @@ impl IntegrationParameters {
* self.joint_damping_ratio)
}
pub fn allowed_linear_error(&self) -> Real {
self.normalized_allowed_linear_error * self.length_unit
}
pub fn max_penetration_correction(&self) -> Real {
if self.normalized_max_penetration_correction != Real::MAX {
self.normalized_max_penetration_correction * self.length_unit
} else {
Real::MAX
}
}
pub fn prediction_distance(&self) -> Real {
self.normalized_prediction_distance * self.length_unit
}
/// Initialize the simulation paramaters with settings matching the TGS-soft solver
/// with warmstarting.
///
@@ -180,21 +217,22 @@ impl IntegrationParameters {
// However we don't want it to be too small and end up with
// tons of islands, reducing SIMD parallelism opportunities.
min_island_size: 128,
allowed_linear_error: 0.001,
max_penetration_correction: Real::MAX,
prediction_distance: 0.002,
normalized_allowed_linear_error: 0.001,
normalized_max_penetration_correction: Real::MAX,
normalized_prediction_distance: 0.002,
max_ccd_substeps: 1,
length_unit: 1.0,
}
}
/// Initialize the simulation paramaters with settings matching the TGS-soft solver
/// Initialize the simulation parameters with settings matching the TGS-soft solver
/// **without** warmstarting.
///
/// The [`IntegrationParameters::tgs_soft()`] configuration should be preferred unless
/// warmstarting proves to be undesirable for your use-case.
pub fn tgs_soft_without_warmstart() -> Self {
Self {
erp: 0.8,
erp: 0.6,
damping_ratio: 1.0,
warmstart_coefficient: 0.0,
num_additional_friction_iterations: 4,

14
src/dynamics/island_manager.rs
View File

@@ -150,6 +150,7 @@ impl IslandManager {
pub(crate) fn update_active_set_with_contacts(
&mut self,
dt: Real,
length_unit: Real,
bodies: &mut RigidBodySet,
colliders: &ColliderSet,
narrow_phase: &NarrowPhase,
@@ -181,7 +182,7 @@ impl IslandManager {
let sq_linvel = rb.vels.linvel.norm_squared();
let sq_angvel = rb.vels.angvel.gdot(rb.vels.angvel);
update_energy(&mut rb.activation, sq_linvel, sq_angvel, dt);
update_energy(length_unit, &mut rb.activation, sq_linvel, sq_angvel, dt);
if rb.activation.time_since_can_sleep >= rb.activation.time_until_sleep {
// Mark them as sleeping for now. This will
@@ -324,8 +325,15 @@ impl IslandManager {
}
}
fn update_energy(activation: &mut RigidBodyActivation, sq_linvel: Real, sq_angvel: Real, dt: Real) {
if sq_linvel < activation.linear_threshold * activation.linear_threshold.abs()
fn update_energy(
length_unit: Real,
activation: &mut RigidBodyActivation,
sq_linvel: Real,
sq_angvel: Real,
dt: Real,
) {
let linear_threshold = activation.normalized_linear_threshold * length_unit;
if sq_linvel < linear_threshold * linear_threshold.abs()
&& sq_angvel < activation.angular_threshold * activation.angular_threshold.abs()
{
activation.time_since_can_sleep += dt;

2
src/dynamics/rigid_body.rs
View File

@@ -1498,7 +1498,7 @@ impl RigidBodyBuilder {
}
if !self.can_sleep {
rb.activation.linear_threshold = -1.0;
rb.activation.normalized_linear_threshold = -1.0;
rb.activation.angular_threshold = -1.0;
}

13
src/dynamics/rigid_body_components.rs
View File

@@ -995,7 +995,10 @@ impl RigidBodyDominance {
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
pub struct RigidBodyActivation {
/// The threshold linear velocity bellow which the body can fall asleep.
pub linear_threshold: Real,
///
/// The value is "normalized", i.e., the actual threshold applied by the physics engine
/// is equal to this value multiplied by [`IntegrationParameters::length_unit`].
pub normalized_linear_threshold: Real,
/// The angular linear velocity bellow which the body can fall asleep.
pub angular_threshold: Real,
/// The amount of time the rigid-body must remain below the thresholds to be put to sleep.
@@ -1014,7 +1017,7 @@ impl Default for RigidBodyActivation {
impl RigidBodyActivation {
/// The default linear velocity bellow which a body can be put to sleep.
pub fn default_linear_threshold() -> Real {
pub fn default_normalized_linear_threshold() -> Real {
0.4
}
@@ -1032,7 +1035,7 @@ impl RigidBodyActivation {
/// Create a new rb_activation status initialised with the default rb_activation threshold and is active.
pub fn active() -> Self {
RigidBodyActivation {
linear_threshold: Self::default_linear_threshold(),
normalized_linear_threshold: Self::default_normalized_linear_threshold(),
angular_threshold: Self::default_angular_threshold(),
time_until_sleep: Self::default_time_until_sleep(),
time_since_can_sleep: 0.0,
@@ -1043,7 +1046,7 @@ impl RigidBodyActivation {
/// Create a new rb_activation status initialised with the default rb_activation threshold and is inactive.
pub fn inactive() -> Self {
RigidBodyActivation {
linear_threshold: Self::default_linear_threshold(),
normalized_linear_threshold: Self::default_normalized_linear_threshold(),
angular_threshold: Self::default_angular_threshold(),
time_until_sleep: Self::default_time_until_sleep(),
time_since_can_sleep: Self::default_time_until_sleep(),
@@ -1054,7 +1057,7 @@ impl RigidBodyActivation {
/// Create a new activation status that prevents the rigid-body from sleeping.
pub fn cannot_sleep() -> Self {
RigidBodyActivation {
linear_threshold: -1.0,
normalized_linear_threshold: -1.0,
angular_threshold: -1.0,
..Self::active()
}

4
src/dynamics/solver/contact_constraint/one_body_constraint.rs
View File

@@ -310,8 +310,8 @@ impl OneBodyConstraintBuilder {
{
let rhs_wo_bias = info.normal_rhs_wo_bias + dist.max(0.0) * inv_dt;
let rhs_bias = erp_inv_dt
* (dist + params.allowed_linear_error)
.clamp(-params.max_penetration_correction, 0.0);
* (dist + params.allowed_linear_error())
.clamp(-params.max_penetration_correction(), 0.0);
let new_rhs = rhs_wo_bias + rhs_bias;
is_fast_contact = is_fast_contact || (-new_rhs * params.dt > ccd_thickness * 0.5);

4
src/dynamics/solver/contact_constraint/one_body_constraint_simd.rs
View File

@@ -265,9 +265,9 @@ impl SimdOneBodyConstraintBuilder {
let cfm_factor = SimdReal::splat(params.cfm_factor());
let dt = SimdReal::splat(params.dt);
let inv_dt = SimdReal::splat(params.inv_dt());
let allowed_lin_err = SimdReal::splat(params.allowed_linear_error);
let allowed_lin_err = SimdReal::splat(params.allowed_linear_error());
let erp_inv_dt = SimdReal::splat(params.erp_inv_dt());
let max_penetration_correction = SimdReal::splat(params.max_penetration_correction);
let max_penetration_correction = SimdReal::splat(params.max_penetration_correction());
let warmstart_coeff = SimdReal::splat(params.warmstart_coefficient);
let rb2 = gather![|ii| &bodies[constraint.solver_vel2[ii]]];

4
src/dynamics/solver/contact_constraint/two_body_constraint.rs
View File

@@ -410,8 +410,8 @@ impl TwoBodyConstraintBuilder {
{
let rhs_wo_bias = info.normal_rhs_wo_bias + dist.max(0.0) * inv_dt;
let rhs_bias = erp_inv_dt
* (dist + params.allowed_linear_error)
.clamp(-params.max_penetration_correction, 0.0);
* (dist + params.allowed_linear_error())
.clamp(-params.max_penetration_correction(), 0.0);
let new_rhs = rhs_wo_bias + rhs_bias;
is_fast_contact = is_fast_contact || (-new_rhs * params.dt > ccd_thickness * 0.5);

4
src/dynamics/solver/contact_constraint/two_body_constraint_simd.rs
View File

@@ -255,9 +255,9 @@ impl TwoBodyConstraintBuilderSimd {
let cfm_factor = SimdReal::splat(params.cfm_factor());
let dt = SimdReal::splat(params.dt);
let inv_dt = SimdReal::splat(params.inv_dt());
let allowed_lin_err = SimdReal::splat(params.allowed_linear_error);
let allowed_lin_err = SimdReal::splat(params.allowed_linear_error());
let erp_inv_dt = SimdReal::splat(params.erp_inv_dt());
let max_penetration_correction = SimdReal::splat(params.max_penetration_correction);
let max_penetration_correction = SimdReal::splat(params.max_penetration_correction());
let warmstart_coeff = SimdReal::splat(params.warmstart_coefficient);
let rb1 = gather![|ii| &bodies[constraint.solver_vel1[ii]]];