Files
rapier/src/dynamics/solver/joint_constraint/fixed_velocity_constraint_wide.rs

540 lines
20 KiB
Rust

use simba::simd::SimdValue;
use crate::dynamics::solver::DeltaVel;
use crate::dynamics::{
FixedJoint, IntegrationParameters, JointGraphEdge, JointIndex, JointParams, RigidBodyIds,
RigidBodyMassProps, RigidBodyPosition, RigidBodyVelocity,
};
use crate::math::{
AngVector, AngularInertia, CrossMatrix, Isometry, Point, Real, SimdReal, SpacialVector, Vector,
DIM, SIMD_WIDTH,
};
use crate::utils::{WAngularInertia, WCross, WCrossMatrix};
#[cfg(feature = "dim3")]
use na::{Cholesky, Matrix6, Vector3, Vector6};
#[cfg(feature = "dim2")]
use {
na::{Matrix3, Vector3},
parry::utils::SdpMatrix3,
};
#[derive(Debug)]
pub(crate) struct WFixedVelocityConstraint {
mj_lambda1: [usize; SIMD_WIDTH],
mj_lambda2: [usize; SIMD_WIDTH],
joint_id: [JointIndex; SIMD_WIDTH],
impulse: SpacialVector<SimdReal>,
#[cfg(feature = "dim3")]
inv_lhs: Matrix6<SimdReal>, // FIXME: replace by Cholesky.
#[cfg(feature = "dim3")]
rhs: Vector6<SimdReal>,
#[cfg(feature = "dim2")]
inv_lhs: Matrix3<SimdReal>,
#[cfg(feature = "dim2")]
rhs: Vector3<SimdReal>,
im1: SimdReal,
im2: SimdReal,
ii1: AngularInertia<SimdReal>,
ii2: AngularInertia<SimdReal>,
ii1_sqrt: AngularInertia<SimdReal>,
ii2_sqrt: AngularInertia<SimdReal>,
r1: Vector<SimdReal>,
r2: Vector<SimdReal>,
}
impl WFixedVelocityConstraint {
pub fn from_params(
params: &IntegrationParameters,
joint_id: [JointIndex; SIMD_WIDTH],
rbs1: (
[&RigidBodyPosition; SIMD_WIDTH],
[&RigidBodyVelocity; SIMD_WIDTH],
[&RigidBodyMassProps; SIMD_WIDTH],
[&RigidBodyIds; SIMD_WIDTH],
),
rbs2: (
[&RigidBodyPosition; SIMD_WIDTH],
[&RigidBodyVelocity; SIMD_WIDTH],
[&RigidBodyMassProps; SIMD_WIDTH],
[&RigidBodyIds; SIMD_WIDTH],
),
cparams: [&FixedJoint; SIMD_WIDTH],
) -> Self {
let (poss1, vels1, mprops1, ids1) = rbs1;
let (poss2, vels2, mprops2, ids2) = rbs2;
let position1 = Isometry::from(gather![|ii| poss1[ii].position]);
let linvel1 = Vector::from(gather![|ii| vels1[ii].linvel]);
let angvel1 = AngVector::<SimdReal>::from(gather![|ii| vels1[ii].angvel]);
let world_com1 = Point::from(gather![|ii| mprops1[ii].world_com]);
let im1 = SimdReal::from(gather![|ii| mprops1[ii].effective_inv_mass]);
let ii1_sqrt = AngularInertia::<SimdReal>::from(gather![
|ii| mprops1[ii].effective_world_inv_inertia_sqrt
]);
let mj_lambda1 = gather![|ii| ids1[ii].active_set_offset];
let position2 = Isometry::from(gather![|ii| poss2[ii].position]);
let linvel2 = Vector::from(gather![|ii| vels2[ii].linvel]);
let angvel2 = AngVector::<SimdReal>::from(gather![|ii| vels2[ii].angvel]);
let world_com2 = Point::from(gather![|ii| mprops2[ii].world_com]);
let im2 = SimdReal::from(gather![|ii| mprops2[ii].effective_inv_mass]);
let ii2_sqrt = AngularInertia::<SimdReal>::from(gather![
|ii| mprops2[ii].effective_world_inv_inertia_sqrt
]);
let mj_lambda2 = gather![|ii| ids2[ii].active_set_offset];
let local_frame1 = Isometry::from(gather![|ii| cparams[ii].local_frame1]);
let local_frame2 = Isometry::from(gather![|ii| cparams[ii].local_frame2]);
let impulse = SpacialVector::from(gather![|ii| cparams[ii].impulse]);
let anchor1 = position1 * local_frame1;
let anchor2 = position2 * local_frame2;
let ii1 = ii1_sqrt.squared();
let ii2 = ii2_sqrt.squared();
let r1 = anchor1.translation.vector - world_com1.coords;
let r2 = anchor2.translation.vector - world_com2.coords;
let rmat1: CrossMatrix<_> = r1.gcross_matrix();
let rmat2: CrossMatrix<_> = r2.gcross_matrix();
#[allow(unused_mut)] // For 2D.
let mut lhs;
#[cfg(feature = "dim3")]
{
let lhs00 =
ii1.quadform(&rmat1).add_diagonal(im1) + ii2.quadform(&rmat2).add_diagonal(im2);
let lhs10 = ii1.transform_matrix(&rmat1) + ii2.transform_matrix(&rmat2);
let lhs11 = (ii1 + ii2).into_matrix();
// Note that Cholesky only reads the lower-triangular part of the matrix
// so we don't need to fill lhs01.
lhs = Matrix6::zeros();
lhs.fixed_slice_mut::<3, 3>(0, 0)
.copy_from(&lhs00.into_matrix());
lhs.fixed_slice_mut::<3, 3>(3, 0).copy_from(&lhs10);
lhs.fixed_slice_mut::<3, 3>(3, 3).copy_from(&lhs11);
}
// In 2D we just unroll the computation because
// it's just easier that way.
#[cfg(feature = "dim2")]
{
let m11 = im1 + im2 + rmat1.x * rmat1.x * ii1 + rmat2.x * rmat2.x * ii2;
let m12 = rmat1.x * rmat1.y * ii1 + rmat2.x * rmat2.y * ii2;
let m22 = im1 + im2 + rmat1.y * rmat1.y * ii1 + rmat2.y * rmat2.y * ii2;
let m13 = rmat1.x * ii1 + rmat2.x * ii2;
let m23 = rmat1.y * ii1 + rmat2.y * ii2;
let m33 = ii1 + ii2;
lhs = SdpMatrix3::new(m11, m12, m13, m22, m23, m33)
}
// NOTE: we don't use cholesky in 2D because we only have a 3x3 matrix
// for which a textbook inverse is still efficient.
#[cfg(feature = "dim2")]
let inv_lhs = lhs.inverse_unchecked().into_matrix(); // FIXME: don't extract the matrix?
#[cfg(feature = "dim3")]
let inv_lhs = Cholesky::new_unchecked(lhs).inverse();
let lin_dvel = -linvel1 - angvel1.gcross(r1) + linvel2 + angvel2.gcross(r2);
let ang_dvel = -angvel1 + angvel2;
let velocity_solve_fraction = SimdReal::splat(params.velocity_solve_fraction);
#[cfg(feature = "dim2")]
let mut rhs = Vector3::new(lin_dvel.x, lin_dvel.y, ang_dvel) * velocity_solve_fraction;
#[cfg(feature = "dim3")]
let mut rhs = Vector6::new(
lin_dvel.x, lin_dvel.y, lin_dvel.z, ang_dvel.x, ang_dvel.y, ang_dvel.z,
) * velocity_solve_fraction;
let velocity_based_erp_inv_dt = params.velocity_based_erp_inv_dt();
if velocity_based_erp_inv_dt != 0.0 {
let velocity_based_erp_inv_dt = SimdReal::splat(velocity_based_erp_inv_dt);
let lin_err = anchor2.translation.vector - anchor1.translation.vector;
let ang_err = anchor2.rotation * anchor1.rotation.inverse();
#[cfg(feature = "dim2")]
{
let ang_err = ang_err.angle();
rhs += Vector3::new(lin_err.x, lin_err.y, ang_err) * velocity_based_erp_inv_dt;
}
#[cfg(feature = "dim3")]
{
let ang_err = Vector3::from(gather![|ii| ang_err.extract(ii).scaled_axis()]);
rhs += Vector6::new(
lin_err.x, lin_err.y, lin_err.z, ang_err.x, ang_err.y, ang_err.z,
) * velocity_based_erp_inv_dt;
}
}
WFixedVelocityConstraint {
joint_id,
mj_lambda1,
mj_lambda2,
im1,
im2,
ii1,
ii2,
ii1_sqrt,
ii2_sqrt,
impulse: impulse * SimdReal::splat(params.warmstart_coeff),
inv_lhs,
r1,
r2,
rhs,
}
}
pub fn warmstart(&self, mj_lambdas: &mut [DeltaVel<Real>]) {
let mut mj_lambda1 = DeltaVel {
linear: Vector::from(gather![|ii| mj_lambdas[self.mj_lambda1[ii] as usize].linear]),
angular: AngVector::from(gather![
|ii| mj_lambdas[self.mj_lambda1[ii] as usize].angular
]),
};
let mut mj_lambda2 = DeltaVel {
linear: Vector::from(gather![|ii| mj_lambdas[self.mj_lambda2[ii] as usize].linear]),
angular: AngVector::from(gather![
|ii| mj_lambdas[self.mj_lambda2[ii] as usize].angular
]),
};
let lin_impulse = self.impulse.fixed_rows::<DIM>(0).into_owned();
#[cfg(feature = "dim2")]
let ang_impulse = self.impulse[2];
#[cfg(feature = "dim3")]
let ang_impulse = self.impulse.fixed_rows::<3>(3).into_owned();
mj_lambda1.linear += lin_impulse * self.im1;
mj_lambda1.angular += self
.ii1_sqrt
.transform_vector(ang_impulse + self.r1.gcross(lin_impulse));
mj_lambda2.linear -= lin_impulse * self.im2;
mj_lambda2.angular -= self
.ii2_sqrt
.transform_vector(ang_impulse + self.r2.gcross(lin_impulse));
for ii in 0..SIMD_WIDTH {
mj_lambdas[self.mj_lambda1[ii] as usize].linear = mj_lambda1.linear.extract(ii);
mj_lambdas[self.mj_lambda1[ii] as usize].angular = mj_lambda1.angular.extract(ii);
}
for ii in 0..SIMD_WIDTH {
mj_lambdas[self.mj_lambda2[ii] as usize].linear = mj_lambda2.linear.extract(ii);
mj_lambdas[self.mj_lambda2[ii] as usize].angular = mj_lambda2.angular.extract(ii);
}
}
pub fn solve(&mut self, mj_lambdas: &mut [DeltaVel<Real>]) {
let mut mj_lambda1: DeltaVel<SimdReal> = DeltaVel {
linear: Vector::from(gather![|ii| mj_lambdas[self.mj_lambda1[ii] as usize].linear]),
angular: AngVector::from(gather![
|ii| mj_lambdas[self.mj_lambda1[ii] as usize].angular
]),
};
let mut mj_lambda2: DeltaVel<SimdReal> = DeltaVel {
linear: Vector::from(gather![|ii| mj_lambdas[self.mj_lambda2[ii] as usize].linear]),
angular: AngVector::from(gather![
|ii| mj_lambdas[self.mj_lambda2[ii] as usize].angular
]),
};
let ang_vel1 = self.ii1_sqrt.transform_vector(mj_lambda1.angular);
let ang_vel2 = self.ii2_sqrt.transform_vector(mj_lambda2.angular);
let dlinvel = -mj_lambda1.linear - ang_vel1.gcross(self.r1)
+ mj_lambda2.linear
+ ang_vel2.gcross(self.r2);
let dangvel = -ang_vel1 + ang_vel2;
#[cfg(feature = "dim2")]
let rhs = Vector3::new(dlinvel.x, dlinvel.y, dangvel) + self.rhs;
#[cfg(feature = "dim3")]
let rhs = Vector6::new(
dlinvel.x, dlinvel.y, dlinvel.z, dangvel.x, dangvel.y, dangvel.z,
) + self.rhs;
let impulse = self.inv_lhs * rhs;
self.impulse += impulse;
let lin_impulse = impulse.fixed_rows::<DIM>(0).into_owned();
#[cfg(feature = "dim2")]
let ang_impulse = impulse[2];
#[cfg(feature = "dim3")]
let ang_impulse = impulse.fixed_rows::<3>(3).into_owned();
mj_lambda1.linear += lin_impulse * self.im1;
mj_lambda1.angular += self
.ii1_sqrt
.transform_vector(ang_impulse + self.r1.gcross(lin_impulse));
mj_lambda2.linear -= lin_impulse * self.im2;
mj_lambda2.angular -= self
.ii2_sqrt
.transform_vector(ang_impulse + self.r2.gcross(lin_impulse));
for ii in 0..SIMD_WIDTH {
mj_lambdas[self.mj_lambda1[ii] as usize].linear = mj_lambda1.linear.extract(ii);
mj_lambdas[self.mj_lambda1[ii] as usize].angular = mj_lambda1.angular.extract(ii);
}
for ii in 0..SIMD_WIDTH {
mj_lambdas[self.mj_lambda2[ii] as usize].linear = mj_lambda2.linear.extract(ii);
mj_lambdas[self.mj_lambda2[ii] as usize].angular = mj_lambda2.angular.extract(ii);
}
}
pub fn writeback_impulses(&self, joints_all: &mut [JointGraphEdge]) {
for ii in 0..SIMD_WIDTH {
let joint = &mut joints_all[self.joint_id[ii]].weight;
if let JointParams::FixedJoint(fixed) = &mut joint.params {
fixed.impulse = self.impulse.extract(ii)
}
}
}
}
#[derive(Debug)]
pub(crate) struct WFixedVelocityGroundConstraint {
mj_lambda2: [usize; SIMD_WIDTH],
joint_id: [JointIndex; SIMD_WIDTH],
impulse: SpacialVector<SimdReal>,
#[cfg(feature = "dim3")]
inv_lhs: Matrix6<SimdReal>, // FIXME: replace by Cholesky.
#[cfg(feature = "dim3")]
rhs: Vector6<SimdReal>,
#[cfg(feature = "dim2")]
inv_lhs: Matrix3<SimdReal>,
#[cfg(feature = "dim2")]
rhs: Vector3<SimdReal>,
im2: SimdReal,
ii2: AngularInertia<SimdReal>,
ii2_sqrt: AngularInertia<SimdReal>,
r2: Vector<SimdReal>,
}
impl WFixedVelocityGroundConstraint {
pub fn from_params(
params: &IntegrationParameters,
joint_id: [JointIndex; SIMD_WIDTH],
rbs1: (
[&RigidBodyPosition; SIMD_WIDTH],
[&RigidBodyVelocity; SIMD_WIDTH],
[&RigidBodyMassProps; SIMD_WIDTH],
),
rbs2: (
[&RigidBodyPosition; SIMD_WIDTH],
[&RigidBodyVelocity; SIMD_WIDTH],
[&RigidBodyMassProps; SIMD_WIDTH],
[&RigidBodyIds; SIMD_WIDTH],
),
cparams: [&FixedJoint; SIMD_WIDTH],
flipped: [bool; SIMD_WIDTH],
) -> Self {
let (poss1, vels1, mprops1) = rbs1;
let (poss2, vels2, mprops2, ids2) = rbs2;
let position1 = Isometry::from(gather![|ii| poss1[ii].position]);
let linvel1 = Vector::from(gather![|ii| vels1[ii].linvel]);
let angvel1 = AngVector::<SimdReal>::from(gather![|ii| vels1[ii].angvel]);
let world_com1 = Point::from(gather![|ii| mprops1[ii].world_com]);
let position2 = Isometry::from(gather![|ii| poss2[ii].position]);
let linvel2 = Vector::from(gather![|ii| vels2[ii].linvel]);
let angvel2 = AngVector::<SimdReal>::from(gather![|ii| vels2[ii].angvel]);
let world_com2 = Point::from(gather![|ii| mprops2[ii].world_com]);
let im2 = SimdReal::from(gather![|ii| mprops2[ii].effective_inv_mass]);
let ii2_sqrt = AngularInertia::<SimdReal>::from(gather![
|ii| mprops2[ii].effective_world_inv_inertia_sqrt
]);
let mj_lambda2 = gather![|ii| ids2[ii].active_set_offset];
let local_frame1 = Isometry::from(gather![|ii| if flipped[ii] {
cparams[ii].local_frame2
} else {
cparams[ii].local_frame1
}]);
let local_frame2 = Isometry::from(gather![|ii| if flipped[ii] {
cparams[ii].local_frame1
} else {
cparams[ii].local_frame2
}]);
let impulse = SpacialVector::from(gather![|ii| cparams[ii].impulse]);
let anchor1 = position1 * local_frame1;
let anchor2 = position2 * local_frame2;
let ii2 = ii2_sqrt.squared();
let r1 = anchor1.translation.vector - world_com1.coords;
let r2 = anchor2.translation.vector - world_com2.coords;
let rmat2: CrossMatrix<_> = r2.gcross_matrix();
#[allow(unused_mut)] // For 2D.
let mut lhs;
#[cfg(feature = "dim3")]
{
let lhs00 = ii2.quadform(&rmat2).add_diagonal(im2);
let lhs10 = ii2.transform_matrix(&rmat2);
let lhs11 = ii2.into_matrix();
lhs = Matrix6::zeros();
lhs.fixed_slice_mut::<3, 3>(0, 0)
.copy_from(&lhs00.into_matrix());
lhs.fixed_slice_mut::<3, 3>(3, 0).copy_from(&lhs10);
lhs.fixed_slice_mut::<3, 3>(3, 3).copy_from(&lhs11);
}
// In 2D we just unroll the computation because
// it's just easier that way.
#[cfg(feature = "dim2")]
{
let m11 = im2 + rmat2.x * rmat2.x * ii2;
let m12 = rmat2.x * rmat2.y * ii2;
let m22 = im2 + rmat2.y * rmat2.y * ii2;
let m13 = rmat2.x * ii2;
let m23 = rmat2.y * ii2;
let m33 = ii2;
lhs = SdpMatrix3::new(m11, m12, m13, m22, m23, m33)
}
#[cfg(feature = "dim2")]
let inv_lhs = lhs.inverse_unchecked().into_matrix(); // FIXME: don't do into_matrix?
#[cfg(feature = "dim3")]
let inv_lhs = Cholesky::new_unchecked(lhs).inverse();
let lin_dvel = linvel2 + angvel2.gcross(r2) - linvel1 - angvel1.gcross(r1);
let ang_dvel = angvel2 - angvel1;
let velocity_solve_fraction = SimdReal::splat(params.velocity_solve_fraction);
#[cfg(feature = "dim2")]
let mut rhs = Vector3::new(lin_dvel.x, lin_dvel.y, ang_dvel) * velocity_solve_fraction;
#[cfg(feature = "dim3")]
let mut rhs = Vector6::new(
lin_dvel.x, lin_dvel.y, lin_dvel.z, ang_dvel.x, ang_dvel.y, ang_dvel.z,
) * velocity_solve_fraction;
let velocity_based_erp_inv_dt = params.velocity_based_erp_inv_dt();
if velocity_based_erp_inv_dt != 0.0 {
let velocity_based_erp_inv_dt = SimdReal::splat(velocity_based_erp_inv_dt);
let lin_err = anchor2.translation.vector - anchor1.translation.vector;
let ang_err = anchor2.rotation * anchor1.rotation.inverse();
#[cfg(feature = "dim2")]
{
let ang_err = ang_err.angle();
rhs += Vector3::new(lin_err.x, lin_err.y, ang_err) * velocity_based_erp_inv_dt;
}
#[cfg(feature = "dim3")]
{
let ang_err = Vector3::from(gather![|ii| ang_err.extract(ii).scaled_axis()]);
rhs += Vector6::new(
lin_err.x, lin_err.y, lin_err.z, ang_err.x, ang_err.y, ang_err.z,
) * velocity_based_erp_inv_dt;
}
}
WFixedVelocityGroundConstraint {
joint_id,
mj_lambda2,
im2,
ii2,
ii2_sqrt,
impulse: impulse * SimdReal::splat(params.warmstart_coeff),
inv_lhs,
r2,
rhs,
}
}
pub fn warmstart(&self, mj_lambdas: &mut [DeltaVel<Real>]) {
let mut mj_lambda2 = DeltaVel {
linear: Vector::from(gather![|ii| mj_lambdas[self.mj_lambda2[ii] as usize].linear]),
angular: AngVector::from(gather![
|ii| mj_lambdas[self.mj_lambda2[ii] as usize].angular
]),
};
let lin_impulse = self.impulse.fixed_rows::<DIM>(0).into_owned();
#[cfg(feature = "dim2")]
let ang_impulse = self.impulse[2];
#[cfg(feature = "dim3")]
let ang_impulse = self.impulse.fixed_rows::<3>(3).into_owned();
mj_lambda2.linear -= lin_impulse * self.im2;
mj_lambda2.angular -= self
.ii2_sqrt
.transform_vector(ang_impulse + self.r2.gcross(lin_impulse));
for ii in 0..SIMD_WIDTH {
mj_lambdas[self.mj_lambda2[ii] as usize].linear = mj_lambda2.linear.extract(ii);
mj_lambdas[self.mj_lambda2[ii] as usize].angular = mj_lambda2.angular.extract(ii);
}
}
pub fn solve(&mut self, mj_lambdas: &mut [DeltaVel<Real>]) {
let mut mj_lambda2: DeltaVel<SimdReal> = DeltaVel {
linear: Vector::from(gather![|ii| mj_lambdas[self.mj_lambda2[ii] as usize].linear]),
angular: AngVector::from(gather![
|ii| mj_lambdas[self.mj_lambda2[ii] as usize].angular
]),
};
let ang_vel2 = self.ii2_sqrt.transform_vector(mj_lambda2.angular);
let dlinvel = mj_lambda2.linear + ang_vel2.gcross(self.r2);
let dangvel = ang_vel2;
#[cfg(feature = "dim2")]
let rhs = Vector3::new(dlinvel.x, dlinvel.y, dangvel) + self.rhs;
#[cfg(feature = "dim3")]
let rhs = Vector6::new(
dlinvel.x, dlinvel.y, dlinvel.z, dangvel.x, dangvel.y, dangvel.z,
) + self.rhs;
let impulse = self.inv_lhs * rhs;
self.impulse += impulse;
let lin_impulse = impulse.fixed_rows::<DIM>(0).into_owned();
#[cfg(feature = "dim2")]
let ang_impulse = impulse[2];
#[cfg(feature = "dim3")]
let ang_impulse = impulse.fixed_rows::<3>(3).into_owned();
mj_lambda2.linear -= lin_impulse * self.im2;
mj_lambda2.angular -= self
.ii2_sqrt
.transform_vector(ang_impulse + self.r2.gcross(lin_impulse));
for ii in 0..SIMD_WIDTH {
mj_lambdas[self.mj_lambda2[ii] as usize].linear = mj_lambda2.linear.extract(ii);
mj_lambdas[self.mj_lambda2[ii] as usize].angular = mj_lambda2.angular.extract(ii);
}
}
// FIXME: duplicated code with the non-ground constraint.
pub fn writeback_impulses(&self, joints_all: &mut [JointGraphEdge]) {
for ii in 0..SIMD_WIDTH {
let joint = &mut joints_all[self.joint_id[ii]].weight;
if let JointParams::FixedJoint(fixed) = &mut joint.params {
fixed.impulse = self.impulse.extract(ii)
}
}
}
}