use super::{ContactConstraintTypes, ContactPointInfos};
use crate::dynamics::solver::SolverVel;
use crate::dynamics::solver::{AnyConstraintMut, SolverBody};
use crate::dynamics::integration_parameters::BLOCK_SOLVER_ENABLED;
use crate::dynamics::{IntegrationParameters, MultibodyJointSet, RigidBodySet};
use crate::geometry::{ContactManifold, ContactManifoldIndex};
use crate::math::{Isometry, Real, Vector, DIM, MAX_MANIFOLD_POINTS};
use crate::utils::{self, SimdAngularInertia, SimdBasis, SimdCross, SimdDot};
use na::{DVector, Matrix2};
use super::{TwoBodyConstraintElement, TwoBodyConstraintNormalPart};
impl AnyConstraintMut<'_, ContactConstraintTypes> {
pub fn remove_bias(&mut self) {
match self {
Self::OneBody(c) => c.remove_cfm_and_bias_from_rhs(),
Self::TwoBodies(c) => c.remove_cfm_and_bias_from_rhs(),
Self::GenericOneBody(c) => c.remove_cfm_and_bias_from_rhs(),
Self::GenericTwoBodies(c) => c.remove_cfm_and_bias_from_rhs(),
#[cfg(feature = "simd-is-enabled")]
Self::SimdOneBody(c) => c.remove_cfm_and_bias_from_rhs(),
#[cfg(feature = "simd-is-enabled")]
Self::SimdTwoBodies(c) => c.remove_cfm_and_bias_from_rhs(),
}
}
pub fn warmstart(
&mut self,
generic_jacobians: &DVector<Real>,
solver_vels: &mut [SolverVel<Real>],
generic_solver_vels: &mut DVector<Real>,
) {
match self {
Self::OneBody(c) => c.warmstart(solver_vels),
Self::TwoBodies(c) => c.warmstart(solver_vels),
Self::GenericOneBody(c) => c.warmstart(generic_jacobians, generic_solver_vels),
Self::GenericTwoBodies(c) => {
c.warmstart(generic_jacobians, solver_vels, generic_solver_vels)
}
#[cfg(feature = "simd-is-enabled")]
Self::SimdOneBody(c) => c.warmstart(solver_vels),
#[cfg(feature = "simd-is-enabled")]
Self::SimdTwoBodies(c) => c.warmstart(solver_vels),
}
}
pub fn solve_restitution(
&mut self,
generic_jacobians: &DVector<Real>,
solver_vels: &mut [SolverVel<Real>],
generic_solver_vels: &mut DVector<Real>,
) {
match self {
Self::OneBody(c) => c.solve(solver_vels, true, false),
Self::TwoBodies(c) => c.solve(solver_vels, true, false),
Self::GenericOneBody(c) => c.solve(generic_jacobians, generic_solver_vels, true, false),
Self::GenericTwoBodies(c) => c.solve(
generic_jacobians,
solver_vels,
generic_solver_vels,
true,
false,
),
#[cfg(feature = "simd-is-enabled")]
Self::SimdOneBody(c) => c.solve(solver_vels, true, false),
#[cfg(feature = "simd-is-enabled")]
Self::SimdTwoBodies(c) => c.solve(solver_vels, true, false),
}
}
pub fn solve_friction(
&mut self,
generic_jacobians: &DVector<Real>,
solver_vels: &mut [SolverVel<Real>],
generic_solver_vels: &mut DVector<Real>,
) {
match self {
Self::OneBody(c) => c.solve(solver_vels, false, true),
Self::TwoBodies(c) => c.solve(solver_vels, false, true),
Self::GenericOneBody(c) => c.solve(generic_jacobians, generic_solver_vels, false, true),
Self::GenericTwoBodies(c) => c.solve(
generic_jacobians,
solver_vels,
generic_solver_vels,
false,
true,
),
#[cfg(feature = "simd-is-enabled")]
Self::SimdOneBody(c) => c.solve(solver_vels, false, true),
#[cfg(feature = "simd-is-enabled")]
Self::SimdTwoBodies(c) => c.solve(solver_vels, false, true),
}
}
pub fn writeback_impulses(&mut self, manifolds_all: &mut [&mut ContactManifold]) {
match self {
Self::OneBody(c) => c.writeback_impulses(manifolds_all),
Self::TwoBodies(c) => c.writeback_impulses(manifolds_all),
Self::GenericOneBody(c) => c.writeback_impulses(manifolds_all),
Self::GenericTwoBodies(c) => c.writeback_impulses(manifolds_all),
#[cfg(feature = "simd-is-enabled")]
Self::SimdOneBody(c) => c.writeback_impulses(manifolds_all),
#[cfg(feature = "simd-is-enabled")]
Self::SimdTwoBodies(c) => c.writeback_impulses(manifolds_all),
}
}
}
#[derive(Copy, Clone, Debug)]
pub(crate) struct TwoBodyConstraint {
pub dir1: Vector<Real>, #[cfg(feature = "dim3")]
pub tangent1: Vector<Real>, pub im1: Vector<Real>,
pub im2: Vector<Real>,
pub cfm_factor: Real,
pub limit: Real,
pub solver_vel1: usize,
pub solver_vel2: usize,
pub manifold_id: ContactManifoldIndex,
pub manifold_contact_id: [u8; MAX_MANIFOLD_POINTS],
pub num_contacts: u8,
pub elements: [TwoBodyConstraintElement<Real>; MAX_MANIFOLD_POINTS],
}
impl TwoBodyConstraint {
pub fn invalid() -> Self {
Self {
dir1: Vector::zeros(),
#[cfg(feature = "dim3")]
tangent1: Vector::zeros(),
im1: Vector::zeros(),
im2: Vector::zeros(),
cfm_factor: 0.0,
limit: 0.0,
solver_vel1: usize::MAX,
solver_vel2: usize::MAX,
manifold_id: ContactManifoldIndex::MAX,
manifold_contact_id: [u8::MAX; MAX_MANIFOLD_POINTS],
num_contacts: u8::MAX,
elements: [TwoBodyConstraintElement::zero(); MAX_MANIFOLD_POINTS],
}
}
}
#[derive(Copy, Clone, Debug)]
pub(crate) struct TwoBodyConstraintBuilder {
pub infos: [ContactPointInfos<Real>; MAX_MANIFOLD_POINTS],
}
impl TwoBodyConstraintBuilder {
pub fn invalid() -> Self {
Self {
infos: [ContactPointInfos::default(); MAX_MANIFOLD_POINTS],
}
}
pub fn generate(
manifold_id: ContactManifoldIndex,
manifold: &ContactManifold,
bodies: &RigidBodySet,
out_builders: &mut [TwoBodyConstraintBuilder],
out_constraints: &mut [TwoBodyConstraint],
) {
assert_eq!(manifold.data.relative_dominance, 0);
let handle1 = manifold.data.rigid_body1.unwrap();
let handle2 = manifold.data.rigid_body2.unwrap();
let rb1 = &bodies[handle1];
let (vels1, mprops1) = (&rb1.vels, &rb1.mprops);
let rb2 = &bodies[handle2];
let (vels2, mprops2) = (&rb2.vels, &rb2.mprops);
let solver_vel1 = rb1.ids.active_set_offset;
let solver_vel2 = rb2.ids.active_set_offset;
let force_dir1 = -manifold.data.normal;
#[cfg(feature = "dim2")]
let tangents1 = force_dir1.orthonormal_basis();
#[cfg(feature = "dim3")]
let tangents1 =
super::compute_tangent_contact_directions(&force_dir1, &vels1.linvel, &vels2.linvel);
for (l, manifold_points) in manifold
.data
.solver_contacts
.chunks(MAX_MANIFOLD_POINTS)
.enumerate()
{
let builder = &mut out_builders[l];
let constraint = &mut out_constraints[l];
constraint.dir1 = force_dir1;
constraint.im1 = mprops1.effective_inv_mass;
constraint.im2 = mprops2.effective_inv_mass;
constraint.solver_vel1 = solver_vel1;
constraint.solver_vel2 = solver_vel2;
constraint.manifold_id = manifold_id;
constraint.num_contacts = manifold_points.len() as u8;
#[cfg(feature = "dim3")]
{
constraint.tangent1 = tangents1[0];
}
for k in 0..manifold_points.len() {
let manifold_point = &manifold_points[k];
let point = manifold_point.point;
let dp1 = point - mprops1.world_com;
let dp2 = point - mprops2.world_com;
let vel1 = vels1.linvel + vels1.angvel.gcross(dp1);
let vel2 = vels2.linvel + vels2.angvel.gcross(dp2);
constraint.limit = manifold_point.friction;
constraint.manifold_contact_id[k] = manifold_point.contact_id;
let normal_rhs_wo_bias;
{
let gcross1 = mprops1
.effective_world_inv_inertia_sqrt
.transform_vector(dp1.gcross(force_dir1));
let gcross2 = mprops2
.effective_world_inv_inertia_sqrt
.transform_vector(dp2.gcross(-force_dir1));
let imsum = mprops1.effective_inv_mass + mprops2.effective_inv_mass;
let projected_mass = utils::inv(
force_dir1.dot(&imsum.component_mul(&force_dir1))
+ gcross1.gdot(gcross1)
+ gcross2.gdot(gcross2),
);
let is_bouncy = manifold_point.is_bouncy() as u32 as Real;
normal_rhs_wo_bias =
(is_bouncy * manifold_point.restitution) * (vel1 - vel2).dot(&force_dir1);
constraint.elements[k].normal_part = TwoBodyConstraintNormalPart {
gcross1,
gcross2,
rhs: na::zero(),
rhs_wo_bias: na::zero(),
impulse: manifold_point.warmstart_impulse,
impulse_accumulator: na::zero(),
r: projected_mass,
r_mat_elts: [0.0; 2],
};
}
{
constraint.elements[k].tangent_part.impulse =
manifold_point.warmstart_tangent_impulse;
for j in 0..DIM - 1 {
let gcross1 = mprops1
.effective_world_inv_inertia_sqrt
.transform_vector(dp1.gcross(tangents1[j]));
let gcross2 = mprops2
.effective_world_inv_inertia_sqrt
.transform_vector(dp2.gcross(-tangents1[j]));
let imsum = mprops1.effective_inv_mass + mprops2.effective_inv_mass;
let r = tangents1[j].dot(&imsum.component_mul(&tangents1[j]))
+ gcross1.gdot(gcross1)
+ gcross2.gdot(gcross2);
let rhs_wo_bias = manifold_point.tangent_velocity.dot(&tangents1[j]);
constraint.elements[k].tangent_part.gcross1[j] = gcross1;
constraint.elements[k].tangent_part.gcross2[j] = gcross2;
constraint.elements[k].tangent_part.rhs_wo_bias[j] = rhs_wo_bias;
constraint.elements[k].tangent_part.rhs[j] = rhs_wo_bias;
constraint.elements[k].tangent_part.r[j] = if cfg!(feature = "dim2") {
utils::inv(r)
} else {
r
};
}
#[cfg(feature = "dim3")]
{
constraint.elements[k].tangent_part.r[2] = 2.0
* (constraint.elements[k].tangent_part.gcross1[0]
.gdot(constraint.elements[k].tangent_part.gcross1[1])
+ constraint.elements[k].tangent_part.gcross2[0]
.gdot(constraint.elements[k].tangent_part.gcross2[1]));
}
}
let infos = ContactPointInfos {
local_p1: rb1
.pos
.position
.inverse_transform_point(&manifold_point.point),
local_p2: rb2
.pos
.position
.inverse_transform_point(&manifold_point.point),
tangent_vel: manifold_point.tangent_velocity,
dist: manifold_point.dist,
normal_rhs_wo_bias,
};
builder.infos[k] = infos;
constraint.manifold_contact_id[k] = manifold_point.contact_id;
}
if BLOCK_SOLVER_ENABLED {
for k in 0..manifold_points.len() / 2 {
let k0 = k * 2;
let k1 = k * 2 + 1;
let mut r_mat = Matrix2::zeros();
let imsum = mprops1.effective_inv_mass + mprops2.effective_inv_mass;
let r0 = constraint.elements[k0].normal_part.r;
let r1 = constraint.elements[k1].normal_part.r;
r_mat.m12 = force_dir1.dot(&imsum.component_mul(&force_dir1))
+ constraint.elements[k0]
.normal_part
.gcross1
.gdot(constraint.elements[k1].normal_part.gcross1)
+ constraint.elements[k0]
.normal_part
.gcross2
.gdot(constraint.elements[k1].normal_part.gcross2);
r_mat.m21 = r_mat.m12;
r_mat.m11 = utils::inv(r0);
r_mat.m22 = utils::inv(r1);
if let Some(inv) = r_mat.try_inverse() {
constraint.elements[k0].normal_part.r_mat_elts = [inv.m11, inv.m22];
constraint.elements[k1].normal_part.r_mat_elts = [inv.m12, r_mat.m12];
} else {
constraint.elements[k0].normal_part.r_mat_elts =
if manifold_points[k0].dist <= manifold_points[k1].dist {
[r0, 0.0]
} else {
[0.0, r1]
};
constraint.elements[k1].normal_part.r_mat_elts = [0.0; 2];
}
}
}
}
}
pub fn update(
&self,
params: &IntegrationParameters,
solved_dt: Real,
bodies: &[SolverBody],
_multibodies: &MultibodyJointSet,
constraint: &mut TwoBodyConstraint,
) {
let rb1 = &bodies[constraint.solver_vel1];
let rb2 = &bodies[constraint.solver_vel2];
self.update_with_positions(params, solved_dt, &rb1.position, &rb2.position, constraint)
}
pub fn update_with_positions(
&self,
params: &IntegrationParameters,
solved_dt: Real,
rb1_pos: &Isometry<Real>,
rb2_pos: &Isometry<Real>,
constraint: &mut TwoBodyConstraint,
) {
let cfm_factor = params.contact_cfm_factor();
let inv_dt = params.inv_dt();
let erp_inv_dt = params.contact_erp_inv_dt();
let all_infos = &self.infos[..constraint.num_contacts as usize];
let all_elements = &mut constraint.elements[..constraint.num_contacts as usize];
#[cfg(feature = "dim2")]
let tangents1 = constraint.dir1.orthonormal_basis();
#[cfg(feature = "dim3")]
let tangents1 = [
constraint.tangent1,
constraint.dir1.cross(&constraint.tangent1),
];
for (info, element) in all_infos.iter().zip(all_elements.iter_mut()) {
let p1 = rb1_pos * info.local_p1 + info.tangent_vel * solved_dt;
let p2 = rb2_pos * info.local_p2;
let dist = info.dist + (p1 - p2).dot(&constraint.dir1);
{
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_corrective_velocity(), 0.0);
let new_rhs = rhs_wo_bias + rhs_bias;
element.normal_part.rhs_wo_bias = rhs_wo_bias;
element.normal_part.rhs = new_rhs;
element.normal_part.impulse_accumulator += element.normal_part.impulse;
element.normal_part.impulse *= params.warmstart_coefficient;
}
{
element.tangent_part.impulse_accumulator += element.tangent_part.impulse;
element.tangent_part.impulse *= params.warmstart_coefficient;
for j in 0..DIM - 1 {
let bias = (p1 - p2).dot(&tangents1[j]) * inv_dt;
element.tangent_part.rhs[j] = element.tangent_part.rhs_wo_bias[j] + bias;
}
}
}
constraint.cfm_factor = cfm_factor;
}
}
impl TwoBodyConstraint {
pub fn warmstart(&mut self, solver_vels: &mut [SolverVel<Real>]) {
let mut solver_vel1 = solver_vels[self.solver_vel1];
let mut solver_vel2 = solver_vels[self.solver_vel2];
TwoBodyConstraintElement::warmstart_group(
&mut self.elements[..self.num_contacts as usize],
&self.dir1,
#[cfg(feature = "dim3")]
&self.tangent1,
&self.im1,
&self.im2,
&mut solver_vel1,
&mut solver_vel2,
);
solver_vels[self.solver_vel1] = solver_vel1;
solver_vels[self.solver_vel2] = solver_vel2;
}
pub fn solve(
&mut self,
solver_vels: &mut [SolverVel<Real>],
solve_normal: bool,
solve_friction: bool,
) {
let mut solver_vel1 = solver_vels[self.solver_vel1];
let mut solver_vel2 = solver_vels[self.solver_vel2];
TwoBodyConstraintElement::solve_group(
self.cfm_factor,
&mut self.elements[..self.num_contacts as usize],
&self.dir1,
#[cfg(feature = "dim3")]
&self.tangent1,
&self.im1,
&self.im2,
self.limit,
&mut solver_vel1,
&mut solver_vel2,
solve_normal,
solve_friction,
);
solver_vels[self.solver_vel1] = solver_vel1;
solver_vels[self.solver_vel2] = solver_vel2;
}
pub fn writeback_impulses(&self, manifolds_all: &mut [&mut ContactManifold]) {
let manifold = &mut manifolds_all[self.manifold_id];
for k in 0..self.num_contacts as usize {
let contact_id = self.manifold_contact_id[k];
let active_contact = &mut manifold.points[contact_id as usize];
active_contact.data.warmstart_impulse = self.elements[k].normal_part.impulse;
active_contact.data.warmstart_tangent_impulse = self.elements[k].tangent_part.impulse;
active_contact.data.impulse = self.elements[k].normal_part.total_impulse();
active_contact.data.tangent_impulse = self.elements[k].tangent_part.total_impulse();
}
}
pub fn remove_cfm_and_bias_from_rhs(&mut self) {
self.cfm_factor = 1.0;
for elt in &mut self.elements {
elt.normal_part.rhs = elt.normal_part.rhs_wo_bias;
elt.tangent_part.rhs = elt.tangent_part.rhs_wo_bias;
}
}
}
#[inline(always)]
#[cfg(feature = "dim3")]
pub(crate) fn compute_tangent_contact_directions<N>(
force_dir1: &Vector<N>,
linvel1: &Vector<N>,
linvel2: &Vector<N>,
) -> [Vector<N>; DIM - 1]
where
N: utils::SimdRealCopy,
Vector<N>: SimdBasis,
{
use na::SimdValue;
let relative_linvel = linvel1 - linvel2;
let mut tangent_relative_linvel =
relative_linvel - force_dir1 * (force_dir1.dot(&relative_linvel));
let tangent_linvel_norm = {
let _disable_fe_except =
crate::utils::DisableFloatingPointExceptionsFlags::disable_floating_point_exceptions();
tangent_relative_linvel.normalize_mut()
};
const THRESHOLD: Real = 1.0e-4;
let use_fallback = tangent_linvel_norm.simd_lt(N::splat(THRESHOLD));
let tangent_fallback = force_dir1.orthonormal_vector();
let tangent1 = tangent_fallback.select(use_fallback, tangent_relative_linvel);
let bitangent1 = force_dir1.cross(&tangent1);
[tangent1, bitangent1]
}