feat: implement new "small-steps" solver + joint improvements
This commit is contained in:
Sébastien Crozet
@@ -0,0 +1,433 @@
|
||||
use crate::dynamics::solver::{GenericRhs, TwoBodyConstraint};
|
||||
use crate::dynamics::{IntegrationParameters, MultibodyJointSet, RigidBodySet};
|
||||
use crate::geometry::{ContactManifold, ContactManifoldIndex};
|
||||
use crate::math::{Real, DIM, MAX_MANIFOLD_POINTS};
|
||||
use crate::utils::{SimdAngularInertia, SimdCross, SimdDot};
|
||||
|
||||
use super::{TwoBodyConstraintBuilder, TwoBodyConstraintElement, TwoBodyConstraintNormalPart};
|
||||
use crate::dynamics::solver::solver_body::SolverBody;
|
||||
use crate::dynamics::solver::{ContactPointInfos, SolverVel};
|
||||
use crate::prelude::RigidBodyHandle;
|
||||
#[cfg(feature = "dim2")]
|
||||
use crate::utils::SimdBasis;
|
||||
use na::DVector;
|
||||
|
||||
#[derive(Copy, Clone)]
|
||||
pub(crate) struct GenericTwoBodyConstraintBuilder {
|
||||
handle1: RigidBodyHandle,
|
||||
handle2: RigidBodyHandle,
|
||||
ccd_thickness: Real,
|
||||
inner: TwoBodyConstraintBuilder,
|
||||
}
|
||||
|
||||
impl GenericTwoBodyConstraintBuilder {
|
||||
pub fn invalid() -> Self {
|
||||
Self {
|
||||
handle1: RigidBodyHandle::invalid(),
|
||||
handle2: RigidBodyHandle::invalid(),
|
||||
ccd_thickness: Real::MAX,
|
||||
inner: TwoBodyConstraintBuilder::invalid(),
|
||||
}
|
||||
}
|
||||
|
||||
pub fn generate(
|
||||
manifold_id: ContactManifoldIndex,
|
||||
manifold: &ContactManifold,
|
||||
bodies: &RigidBodySet,
|
||||
multibodies: &MultibodyJointSet,
|
||||
out_builders: &mut [GenericTwoBodyConstraintBuilder],
|
||||
out_constraints: &mut [GenericTwoBodyConstraint],
|
||||
jacobians: &mut DVector<Real>,
|
||||
jacobian_id: &mut usize,
|
||||
) {
|
||||
let handle1 = manifold.data.rigid_body1.unwrap();
|
||||
let handle2 = manifold.data.rigid_body2.unwrap();
|
||||
|
||||
let rb1 = &bodies[handle1];
|
||||
let rb2 = &bodies[handle2];
|
||||
|
||||
let (vels1, mprops1, type1) = (&rb1.vels, &rb1.mprops, &rb1.body_type);
|
||||
let (vels2, mprops2, type2) = (&rb2.vels, &rb2.mprops, &rb2.body_type);
|
||||
|
||||
let multibody1 = multibodies
|
||||
.rigid_body_link(handle1)
|
||||
.map(|m| (&multibodies[m.multibody], m.id));
|
||||
let multibody2 = multibodies
|
||||
.rigid_body_link(handle2)
|
||||
.map(|m| (&multibodies[m.multibody], m.id));
|
||||
let solver_vel1 = multibody1
|
||||
.map(|mb| mb.0.solver_id)
|
||||
.unwrap_or(if type1.is_dynamic() {
|
||||
rb1.ids.active_set_offset
|
||||
} else {
|
||||
0
|
||||
});
|
||||
let solver_vel2 = multibody2
|
||||
.map(|mb| mb.0.solver_id)
|
||||
.unwrap_or(if type2.is_dynamic() {
|
||||
rb2.ids.active_set_offset
|
||||
} else {
|
||||
0
|
||||
});
|
||||
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);
|
||||
|
||||
let multibodies_ndof = multibody1.map(|m| m.0.ndofs()).unwrap_or(0)
|
||||
+ multibody2.map(|m| m.0.ndofs()).unwrap_or(0);
|
||||
// For each solver contact we generate DIM constraints, and each constraints appends
|
||||
// the multibodies jacobian and weighted jacobians
|
||||
let required_jacobian_len =
|
||||
*jacobian_id + manifold.data.solver_contacts.len() * multibodies_ndof * 2 * DIM;
|
||||
|
||||
if jacobians.nrows() < required_jacobian_len && !cfg!(feature = "parallel") {
|
||||
jacobians.resize_vertically_mut(required_jacobian_len, 0.0);
|
||||
}
|
||||
|
||||
for (l, manifold_points) in manifold
|
||||
.data
|
||||
.solver_contacts
|
||||
.chunks(MAX_MANIFOLD_POINTS)
|
||||
.enumerate()
|
||||
{
|
||||
let chunk_j_id = *jacobian_id;
|
||||
|
||||
let builder = &mut out_builders[l];
|
||||
let constraint = &mut out_constraints[l];
|
||||
constraint.inner.dir1 = force_dir1;
|
||||
constraint.inner.im1 = if type1.is_dynamic() {
|
||||
mprops1.effective_inv_mass
|
||||
} else {
|
||||
na::zero()
|
||||
};
|
||||
constraint.inner.im2 = if type2.is_dynamic() {
|
||||
mprops2.effective_inv_mass
|
||||
} else {
|
||||
na::zero()
|
||||
};
|
||||
constraint.inner.solver_vel1 = solver_vel1;
|
||||
constraint.inner.solver_vel2 = solver_vel2;
|
||||
constraint.inner.manifold_id = manifold_id;
|
||||
constraint.inner.num_contacts = manifold_points.len() as u8;
|
||||
#[cfg(feature = "dim3")]
|
||||
{
|
||||
constraint.inner.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.inner.limit = manifold_point.friction;
|
||||
constraint.inner.manifold_contact_id[k] = manifold_point.contact_id;
|
||||
|
||||
// Normal part.
|
||||
let normal_rhs_wo_bias;
|
||||
{
|
||||
let torque_dir1 = dp1.gcross(force_dir1);
|
||||
let torque_dir2 = dp2.gcross(-force_dir1);
|
||||
|
||||
let gcross1 = if type1.is_dynamic() {
|
||||
mprops1
|
||||
.effective_world_inv_inertia_sqrt
|
||||
.transform_vector(torque_dir1)
|
||||
} else {
|
||||
na::zero()
|
||||
};
|
||||
let gcross2 = if type2.is_dynamic() {
|
||||
mprops2
|
||||
.effective_world_inv_inertia_sqrt
|
||||
.transform_vector(torque_dir2)
|
||||
} else {
|
||||
na::zero()
|
||||
};
|
||||
|
||||
let inv_r1 = if let Some((mb1, link_id1)) = multibody1.as_ref() {
|
||||
mb1.fill_jacobians(
|
||||
*link_id1,
|
||||
force_dir1,
|
||||
#[cfg(feature = "dim2")]
|
||||
na::vector!(torque_dir1),
|
||||
#[cfg(feature = "dim3")]
|
||||
torque_dir1,
|
||||
jacobian_id,
|
||||
jacobians,
|
||||
)
|
||||
.0
|
||||
} else if type1.is_dynamic() {
|
||||
force_dir1.dot(&mprops1.effective_inv_mass.component_mul(&force_dir1))
|
||||
+ gcross1.gdot(gcross1)
|
||||
} else {
|
||||
0.0
|
||||
};
|
||||
|
||||
let inv_r2 = if let Some((mb2, link_id2)) = multibody2.as_ref() {
|
||||
mb2.fill_jacobians(
|
||||
*link_id2,
|
||||
-force_dir1,
|
||||
#[cfg(feature = "dim2")]
|
||||
na::vector!(torque_dir2),
|
||||
#[cfg(feature = "dim3")]
|
||||
torque_dir2,
|
||||
jacobian_id,
|
||||
jacobians,
|
||||
)
|
||||
.0
|
||||
} else if type2.is_dynamic() {
|
||||
force_dir1.dot(&mprops2.effective_inv_mass.component_mul(&force_dir1))
|
||||
+ gcross2.gdot(gcross2)
|
||||
} else {
|
||||
0.0
|
||||
};
|
||||
|
||||
let r = crate::utils::inv(inv_r1 + inv_r2);
|
||||
|
||||
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.inner.elements[k].normal_part = TwoBodyConstraintNormalPart {
|
||||
gcross1,
|
||||
gcross2,
|
||||
rhs: na::zero(),
|
||||
rhs_wo_bias: na::zero(),
|
||||
total_impulse: na::zero(),
|
||||
impulse: na::zero(),
|
||||
r,
|
||||
};
|
||||
}
|
||||
|
||||
// Tangent parts.
|
||||
{
|
||||
constraint.inner.elements[k].tangent_part.impulse = na::zero();
|
||||
|
||||
for j in 0..DIM - 1 {
|
||||
let torque_dir1 = dp1.gcross(tangents1[j]);
|
||||
let gcross1 = if type1.is_dynamic() {
|
||||
mprops1
|
||||
.effective_world_inv_inertia_sqrt
|
||||
.transform_vector(torque_dir1)
|
||||
} else {
|
||||
na::zero()
|
||||
};
|
||||
constraint.inner.elements[k].tangent_part.gcross1[j] = gcross1;
|
||||
|
||||
let torque_dir2 = dp2.gcross(-tangents1[j]);
|
||||
let gcross2 = if type2.is_dynamic() {
|
||||
mprops2
|
||||
.effective_world_inv_inertia_sqrt
|
||||
.transform_vector(torque_dir2)
|
||||
} else {
|
||||
na::zero()
|
||||
};
|
||||
constraint.inner.elements[k].tangent_part.gcross2[j] = gcross2;
|
||||
|
||||
let inv_r1 = if let Some((mb1, link_id1)) = multibody1.as_ref() {
|
||||
mb1.fill_jacobians(
|
||||
*link_id1,
|
||||
tangents1[j],
|
||||
#[cfg(feature = "dim2")]
|
||||
na::vector![torque_dir1],
|
||||
#[cfg(feature = "dim3")]
|
||||
torque_dir1,
|
||||
jacobian_id,
|
||||
jacobians,
|
||||
)
|
||||
.0
|
||||
} else if type1.is_dynamic() {
|
||||
force_dir1.dot(&mprops1.effective_inv_mass.component_mul(&force_dir1))
|
||||
+ gcross1.gdot(gcross1)
|
||||
} else {
|
||||
0.0
|
||||
};
|
||||
|
||||
let inv_r2 = if let Some((mb2, link_id2)) = multibody2.as_ref() {
|
||||
mb2.fill_jacobians(
|
||||
*link_id2,
|
||||
-tangents1[j],
|
||||
#[cfg(feature = "dim2")]
|
||||
na::vector![torque_dir2],
|
||||
#[cfg(feature = "dim3")]
|
||||
torque_dir2,
|
||||
jacobian_id,
|
||||
jacobians,
|
||||
)
|
||||
.0
|
||||
} else if type2.is_dynamic() {
|
||||
force_dir1.dot(&mprops2.effective_inv_mass.component_mul(&force_dir1))
|
||||
+ gcross2.gdot(gcross2)
|
||||
} else {
|
||||
0.0
|
||||
};
|
||||
|
||||
let r = crate::utils::inv(inv_r1 + inv_r2);
|
||||
let rhs_wo_bias = manifold_point.tangent_velocity.dot(&tangents1[j]);
|
||||
|
||||
constraint.inner.elements[k].tangent_part.rhs_wo_bias[j] = rhs_wo_bias;
|
||||
constraint.inner.elements[k].tangent_part.rhs[j] = rhs_wo_bias;
|
||||
|
||||
// TODO: in 3D, we should take into account gcross[0].dot(gcross[1])
|
||||
// in lhs. See the corresponding code on the `velocity_constraint.rs`
|
||||
// file.
|
||||
constraint.inner.elements[k].tangent_part.r[j] = r;
|
||||
}
|
||||
}
|
||||
|
||||
// Builder.
|
||||
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.handle1 = handle1;
|
||||
builder.handle2 = handle2;
|
||||
builder.ccd_thickness = rb1.ccd.ccd_thickness + rb2.ccd.ccd_thickness;
|
||||
builder.inner.infos[k] = infos;
|
||||
constraint.inner.manifold_contact_id[k] = manifold_point.contact_id;
|
||||
}
|
||||
|
||||
let ndofs1 = multibody1.map(|mb| mb.0.ndofs()).unwrap_or(0);
|
||||
let ndofs2 = multibody2.map(|mb| mb.0.ndofs()).unwrap_or(0);
|
||||
|
||||
// NOTE: we use the generic constraint for non-dynamic bodies because this will
|
||||
// reduce all ops to nothing because its ndofs will be zero.
|
||||
let generic_constraint_mask = (multibody1.is_some() as u8)
|
||||
| ((multibody2.is_some() as u8) << 1)
|
||||
| (!type1.is_dynamic() as u8)
|
||||
| ((!type2.is_dynamic() as u8) << 1);
|
||||
|
||||
constraint.j_id = chunk_j_id;
|
||||
constraint.ndofs1 = ndofs1;
|
||||
constraint.ndofs2 = ndofs2;
|
||||
constraint.generic_constraint_mask = generic_constraint_mask;
|
||||
}
|
||||
}
|
||||
|
||||
pub fn update(
|
||||
&self,
|
||||
params: &IntegrationParameters,
|
||||
solved_dt: Real,
|
||||
bodies: &[SolverBody],
|
||||
multibodies: &MultibodyJointSet,
|
||||
constraint: &mut GenericTwoBodyConstraint,
|
||||
) {
|
||||
// We don’t update jacobians so the update is mostly identical to the non-generic velocity constraint.
|
||||
let pos1 = multibodies
|
||||
.rigid_body_link(self.handle1)
|
||||
.map(|m| &multibodies[m.multibody].link(m.id).unwrap().local_to_world)
|
||||
.unwrap_or_else(|| &bodies[constraint.inner.solver_vel1].position);
|
||||
let pos2 = multibodies
|
||||
.rigid_body_link(self.handle2)
|
||||
.map(|m| &multibodies[m.multibody].link(m.id).unwrap().local_to_world)
|
||||
.unwrap_or_else(|| &bodies[constraint.inner.solver_vel2].position);
|
||||
|
||||
self.inner.update_with_positions(
|
||||
params,
|
||||
solved_dt,
|
||||
pos1,
|
||||
pos2,
|
||||
self.ccd_thickness,
|
||||
&mut constraint.inner,
|
||||
);
|
||||
}
|
||||
}
|
||||
|
||||
#[derive(Copy, Clone, Debug)]
|
||||
pub(crate) struct GenericTwoBodyConstraint {
|
||||
// We just build the generic constraint on top of the velocity constraint,
|
||||
// adding some information we can use in the generic case.
|
||||
pub inner: TwoBodyConstraint,
|
||||
pub j_id: usize,
|
||||
pub ndofs1: usize,
|
||||
pub ndofs2: usize,
|
||||
pub generic_constraint_mask: u8,
|
||||
}
|
||||
|
||||
impl GenericTwoBodyConstraint {
|
||||
pub fn invalid() -> Self {
|
||||
Self {
|
||||
inner: TwoBodyConstraint::invalid(),
|
||||
j_id: usize::MAX,
|
||||
ndofs1: usize::MAX,
|
||||
ndofs2: usize::MAX,
|
||||
generic_constraint_mask: u8::MAX,
|
||||
}
|
||||
}
|
||||
|
||||
pub fn solve(
|
||||
&mut self,
|
||||
jacobians: &DVector<Real>,
|
||||
solver_vels: &mut [SolverVel<Real>],
|
||||
generic_solver_vels: &mut DVector<Real>,
|
||||
solve_restitution: bool,
|
||||
solve_friction: bool,
|
||||
) {
|
||||
let mut solver_vel1 = if self.generic_constraint_mask & 0b01 == 0 {
|
||||
GenericRhs::SolverVel(solver_vels[self.inner.solver_vel1 as usize])
|
||||
} else {
|
||||
GenericRhs::GenericId(self.inner.solver_vel1 as usize)
|
||||
};
|
||||
|
||||
let mut solver_vel2 = if self.generic_constraint_mask & 0b10 == 0 {
|
||||
GenericRhs::SolverVel(solver_vels[self.inner.solver_vel2 as usize])
|
||||
} else {
|
||||
GenericRhs::GenericId(self.inner.solver_vel2 as usize)
|
||||
};
|
||||
|
||||
let elements = &mut self.inner.elements[..self.inner.num_contacts as usize];
|
||||
TwoBodyConstraintElement::generic_solve_group(
|
||||
self.inner.cfm_factor,
|
||||
elements,
|
||||
jacobians,
|
||||
&self.inner.dir1,
|
||||
#[cfg(feature = "dim3")]
|
||||
&self.inner.tangent1,
|
||||
&self.inner.im1,
|
||||
&self.inner.im2,
|
||||
self.inner.limit,
|
||||
self.ndofs1,
|
||||
self.ndofs2,
|
||||
self.j_id,
|
||||
&mut solver_vel1,
|
||||
&mut solver_vel2,
|
||||
generic_solver_vels,
|
||||
solve_restitution,
|
||||
solve_friction,
|
||||
);
|
||||
|
||||
if let GenericRhs::SolverVel(solver_vel1) = solver_vel1 {
|
||||
solver_vels[self.inner.solver_vel1 as usize] = solver_vel1;
|
||||
}
|
||||
|
||||
if let GenericRhs::SolverVel(solver_vel2) = solver_vel2 {
|
||||
solver_vels[self.inner.solver_vel2 as usize] = solver_vel2;
|
||||
}
|
||||
}
|
||||
|
||||
pub fn writeback_impulses(&self, manifolds_all: &mut [&mut ContactManifold]) {
|
||||
self.inner.writeback_impulses(manifolds_all);
|
||||
}
|
||||
|
||||
pub fn remove_cfm_and_bias_from_rhs(&mut self) {
|
||||
self.inner.remove_cfm_and_bias_from_rhs();
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user