Use contact ids instead of contact reordering in order to identify the impulse writeback location.

This commit is contained in:
Crozet Sébastien
2021-02-22 17:51:40 +01:00
parent d31a327b45
commit ad5c10672e
6 changed files with 52 additions and 45 deletions

View File

@@ -124,7 +124,7 @@ pub(crate) struct VelocityConstraint {
pub mj_lambda1: usize,
pub mj_lambda2: usize,
pub manifold_id: ContactManifoldIndex,
pub manifold_contact_id: usize,
pub manifold_contact_id: [u8; MAX_MANIFOLD_POINTS],
pub num_contacts: u8,
pub elements: [VelocityConstraintElement; MAX_MANIFOLD_POINTS],
}
@@ -168,7 +168,7 @@ impl VelocityConstraint {
mj_lambda1,
mj_lambda2,
manifold_id,
manifold_contact_id: l * MAX_MANIFOLD_POINTS,
manifold_contact_id: [0; MAX_MANIFOLD_POINTS],
num_contacts: manifold_points.len() as u8,
};
@@ -211,7 +211,7 @@ impl VelocityConstraint {
constraint.mj_lambda1 = mj_lambda1;
constraint.mj_lambda2 = mj_lambda2;
constraint.manifold_id = manifold_id;
constraint.manifold_contact_id = l * MAX_MANIFOLD_POINTS;
constraint.manifold_contact_id = [0; MAX_MANIFOLD_POINTS];
constraint.num_contacts = manifold_points.len() as u8;
}
@@ -224,6 +224,8 @@ impl VelocityConstraint {
let vel2 = rb2.linvel + rb2.angvel.gcross(dp2);
constraint.limit = manifold_point.friction;
constraint.manifold_contact_id[k] = manifold_point.contact_id;
// Normal part.
{
let gcross1 = rb1
@@ -382,19 +384,18 @@ impl VelocityConstraint {
pub fn writeback_impulses(&self, manifolds_all: &mut [&mut ContactManifold]) {
let manifold = &mut manifolds_all[self.manifold_id];
let k_base = self.manifold_contact_id;
for k in 0..self.num_contacts as usize {
let active_contacts = &mut manifold.points[..manifold.data.num_active_contacts()];
active_contacts[k_base + k].data.impulse = self.elements[k].normal_part.impulse;
let contact_id = self.manifold_contact_id[k];
let active_contact = &mut manifold.points[contact_id as usize];
active_contact.data.impulse = self.elements[k].normal_part.impulse;
#[cfg(feature = "dim2")]
{
active_contacts[k_base + k].data.tangent_impulse =
self.elements[k].tangent_part[0].impulse;
active_contacts.data.tangent_impulse = self.elements[k].tangent_part[0].impulse;
}
#[cfg(feature = "dim3")]
{
active_contacts[k_base + k].data.tangent_impulse = [
active_contact.data.tangent_impulse = [
self.elements[k].tangent_part[0].impulse,
self.elements[k].tangent_part[1].impulse,
];

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@@ -55,7 +55,7 @@ pub(crate) struct WVelocityConstraint {
pub mj_lambda1: [usize; SIMD_WIDTH],
pub mj_lambda2: [usize; SIMD_WIDTH],
pub manifold_id: [ContactManifoldIndex; SIMD_WIDTH],
pub manifold_contact_id: usize,
pub manifold_contact_id: [[u8; SIMD_WIDTH]; MAX_MANIFOLD_POINTS],
}
impl WVelocityConstraint {
@@ -116,7 +116,7 @@ impl WVelocityConstraint {
mj_lambda1,
mj_lambda2,
manifold_id,
manifold_contact_id: l,
manifold_contact_id: [[0; SIMD_WIDTH]; MAX_MANIFOLD_POINTS],
num_contacts: num_points as u8,
};
@@ -141,6 +141,8 @@ impl WVelocityConstraint {
let vel2 = linvel2 + angvel2.gcross(dp2);
constraint.limit = friction;
constraint.manifold_contact_id[k] =
array![|ii| manifold_points[ii][k].contact_id; SIMD_WIDTH];
// Normal part.
{
@@ -332,17 +334,17 @@ impl WVelocityConstraint {
for ii in 0..SIMD_WIDTH {
let manifold = &mut manifolds_all[self.manifold_id[ii]];
let k_base = self.manifold_contact_id;
let active_contacts = &mut manifold.points[..manifold.data.num_active_contacts()];
active_contacts[k_base + k].data.impulse = impulses[ii];
let contact_id = self.manifold_contact_id[k][ii];
let active_contact = &mut manifold.points[contact_id as usize];
active_contact.data.impulse = impulses[ii];
#[cfg(feature = "dim2")]
{
active_contacts[k_base + k].data.tangent_impulse = tangent_impulses[ii];
active_contact.data.tangent_impulse = tangent_impulses[ii];
}
#[cfg(feature = "dim3")]
{
active_contacts[k_base + k].data.tangent_impulse =
active_contact.data.tangent_impulse =
[tangent_impulses[ii], bitangent_impulses[ii]];
}
}

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@@ -49,7 +49,7 @@ pub(crate) struct VelocityGroundConstraint {
pub limit: Real,
pub mj_lambda2: usize,
pub manifold_id: ContactManifoldIndex,
pub manifold_contact_id: usize,
pub manifold_contact_id: [u8; MAX_MANIFOLD_POINTS],
pub num_contacts: u8,
pub elements: [VelocityGroundConstraintElement; MAX_MANIFOLD_POINTS],
}
@@ -92,7 +92,7 @@ impl VelocityGroundConstraint {
limit: 0.0,
mj_lambda2,
manifold_id,
manifold_contact_id: l * MAX_MANIFOLD_POINTS,
manifold_contact_id: [0; MAX_MANIFOLD_POINTS],
num_contacts: manifold_points.len() as u8,
};
@@ -133,7 +133,7 @@ impl VelocityGroundConstraint {
constraint.limit = 0.0;
constraint.mj_lambda2 = mj_lambda2;
constraint.manifold_id = manifold_id;
constraint.manifold_contact_id = l * MAX_MANIFOLD_POINTS;
constraint.manifold_contact_id = [0; MAX_MANIFOLD_POINTS];
constraint.num_contacts = manifold_points.len() as u8;
}
@@ -145,6 +145,7 @@ impl VelocityGroundConstraint {
let vel2 = rb2.linvel + rb2.angvel.gcross(dp2);
constraint.limit = manifold_point.friction;
constraint.manifold_contact_id[k] = manifold_point.contact_id;
// Normal part.
{
@@ -267,19 +268,18 @@ impl VelocityGroundConstraint {
// FIXME: duplicated code. This is exactly the same as in the non-ground velocity constraint.
pub fn writeback_impulses(&self, manifolds_all: &mut [&mut ContactManifold]) {
let manifold = &mut manifolds_all[self.manifold_id];
let k_base = self.manifold_contact_id;
for k in 0..self.num_contacts as usize {
let active_contacts = &mut manifold.points[..manifold.data.num_active_contacts()];
active_contacts[k_base + k].data.impulse = self.elements[k].normal_part.impulse;
let contact_id = self.manifold_contact_id[k];
let active_contact = &mut manifold.points[contact_id as usize];
active_contact.data.impulse = self.elements[k].normal_part.impulse;
#[cfg(feature = "dim2")]
{
active_contacts[k_base + k].data.tangent_impulse =
self.elements[k].tangent_part[0].impulse;
active_contact.data.tangent_impulse = self.elements[k].tangent_part[0].impulse;
}
#[cfg(feature = "dim3")]
{
active_contacts[k_base + k].data.tangent_impulse = [
active_contact.data.tangent_impulse = [
self.elements[k].tangent_part[0].impulse,
self.elements[k].tangent_part[1].impulse,
];

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@@ -51,7 +51,7 @@ pub(crate) struct WVelocityGroundConstraint {
pub limit: SimdReal,
pub mj_lambda2: [usize; SIMD_WIDTH],
pub manifold_id: [ContactManifoldIndex; SIMD_WIDTH],
pub manifold_contact_id: usize,
pub manifold_contact_id: [[u8; SIMD_WIDTH]; MAX_MANIFOLD_POINTS],
}
impl WVelocityGroundConstraint {
@@ -111,7 +111,7 @@ impl WVelocityGroundConstraint {
limit: SimdReal::splat(0.0),
mj_lambda2,
manifold_id,
manifold_contact_id: l,
manifold_contact_id: [[0; SIMD_WIDTH]; MAX_MANIFOLD_POINTS],
num_contacts: num_points as u8,
};
@@ -135,6 +135,8 @@ impl WVelocityGroundConstraint {
let vel2 = linvel2 + angvel2.gcross(dp2);
constraint.limit = friction;
constraint.manifold_contact_id[k] =
array![|ii| manifold_points[ii][k].contact_id; SIMD_WIDTH];
// Normal part.
{
@@ -281,17 +283,17 @@ impl WVelocityGroundConstraint {
for ii in 0..SIMD_WIDTH {
let manifold = &mut manifolds_all[self.manifold_id[ii]];
let k_base = self.manifold_contact_id;
let active_contacts = &mut manifold.points[..manifold.data.num_active_contacts()];
active_contacts[k_base + k].data.impulse = impulses[ii];
let contact_id = self.manifold_contact_id[k][ii];
let active_contact = &mut manifold.points[contact_id as usize];
active_contact.data.impulse = impulses[ii];
#[cfg(feature = "dim2")]
{
active_contacts[k_base + k].data.tangent_impulse = tangent_impulses[ii];
active_contact.data.tangent_impulse = tangent_impulses[ii];
}
#[cfg(feature = "dim3")]
{
active_contacts[k_base + k].data.tangent_impulse =
active_contact.data.tangent_impulse =
[tangent_impulses[ii], bitangent_impulses[ii]];
}
}

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@@ -110,6 +110,8 @@ pub struct ContactManifoldData {
#[derive(Copy, Clone, Debug)]
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
pub struct SolverContact {
/// The index of the manifold contact used to generate this solver contact.
pub contact_id: u8,
/// The world-space contact point.
pub point: Point<Real>,
/// The distance between the two original contacts points along the contact normal.
@@ -203,3 +205,9 @@ impl ContactManifoldData {
// manifold.data.warmstart_multiplier = Self::min_warmstart_multiplier()
// }
}
/// A contact manifold that can be modified by the user.
pub struct ModifiableContactManifold<'a> {
manifold: &'a super::ContactManifold,
solver_contacts: &'a mut Vec<SolverContact>,
}

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@@ -546,15 +546,17 @@ impl NarrowPhase {
manifold.data.solver_flags = solver_flags;
manifold.data.normal = world_pos1 * manifold.local_n1;
// Sort contacts to keep only these with distances bellow
// the prediction, and generate solver contacts.
let mut first_inactive_index = manifold.points.len();
// Generate solver contacts.
for (contact_id, contact) in manifold.points.iter().enumerate() {
assert!(
contact_id <= u8::MAX as usize,
"A contact manifold cannot contain more than 255 contacts currently."
);
while manifold.data.num_active_contacts() != first_inactive_index {
let contact = &manifold.points[manifold.data.num_active_contacts()];
if contact.dist < prediction_distance {
// Generate the solver contact.
let solver_contact = SolverContact {
contact_id: contact_id as u8,
point: world_pos1 * contact.local_p1
+ manifold.data.normal * contact.dist / 2.0,
dist: contact.dist,
@@ -570,14 +572,6 @@ impl NarrowPhase {
has_any_active_contact = true;
continue;
}
// If we reach this code, then the contact must be ignored by the constraints solver.
// Swap with the last contact.
manifold.points.swap(
manifold.data.num_active_contacts(),
first_inactive_index - 1,
);
first_inactive_index -= 1;
}
}