First public release of Rapier.v0.1.0

1 files changed, 344 insertions, 0 deletions

diff --git a/src/dynamics/solver/velocity_constraint_wide.rs b/src/dynamics/solver/velocity_constraint_wide.rs
new file mode 100644
index 0000000..8f387a5
--- /dev/null
+++ b/src/dynamics/solver/velocity_constraint_wide.rs
@@ -0,0 +1,344 @@
+use super::{AnyVelocityConstraint, DeltaVel};
+use crate::dynamics::{IntegrationParameters, RigidBodySet};
+use crate::geometry::{ContactManifold, ContactManifoldIndex};
+use crate::math::{
+    AngVector, AngularInertia, Isometry, Point, SimdFloat, Vector, DIM, MAX_MANIFOLD_POINTS,
+    SIMD_WIDTH,
+};
+use crate::utils::{WAngularInertia, WBasis, WCross, WDot};
+use num::Zero;
+use simba::simd::{SimdPartialOrd, SimdValue};
+
+#[derive(Copy, Clone, Debug)]
+pub(crate) struct WVelocityConstraintElementPart {
+    pub gcross1: AngVector<SimdFloat>,
+    pub gcross2: AngVector<SimdFloat>,
+    pub rhs: SimdFloat,
+    pub impulse: SimdFloat,
+    pub r: SimdFloat,
+}
+
+impl WVelocityConstraintElementPart {
+    pub fn zero() -> Self {
+        Self {
+            gcross1: AngVector::zero(),
+            gcross2: AngVector::zero(),
+            rhs: SimdFloat::zero(),
+            impulse: SimdFloat::zero(),
+            r: SimdFloat::zero(),
+        }
+    }
+}
+
+#[derive(Copy, Clone, Debug)]
+pub(crate) struct WVelocityConstraintElement {
+    pub normal_part: WVelocityConstraintElementPart,
+    pub tangent_parts: [WVelocityConstraintElementPart; DIM - 1],
+}
+
+impl WVelocityConstraintElement {
+    pub fn zero() -> Self {
+        Self {
+            normal_part: WVelocityConstraintElementPart::zero(),
+            tangent_parts: [WVelocityConstraintElementPart::zero(); DIM - 1],
+        }
+    }
+}
+
+#[derive(Copy, Clone, Debug)]
+pub(crate) struct WVelocityConstraint {
+    pub dir1: Vector<SimdFloat>, // Non-penetration force direction for the first body.
+    pub elements: [WVelocityConstraintElement; MAX_MANIFOLD_POINTS],
+    pub num_contacts: u8,
+    pub im1: SimdFloat,
+    pub im2: SimdFloat,
+    pub limit: SimdFloat,
+    pub mj_lambda1: [usize; SIMD_WIDTH],
+    pub mj_lambda2: [usize; SIMD_WIDTH],
+    pub manifold_id: [ContactManifoldIndex; SIMD_WIDTH],
+    pub manifold_contact_id: usize,
+}
+
+impl WVelocityConstraint {
+    pub fn generate(
+        params: &IntegrationParameters,
+        manifold_id: [ContactManifoldIndex; SIMD_WIDTH],
+        manifolds: [&ContactManifold; SIMD_WIDTH],
+        bodies: &RigidBodySet,
+        out_constraints: &mut Vec<AnyVelocityConstraint>,
+        push: bool,
+    ) {
+        let inv_dt = SimdFloat::splat(params.inv_dt());
+        let rbs1 = array![|ii| &bodies[manifolds[ii].body_pair.body1]; SIMD_WIDTH];
+        let rbs2 = array![|ii| &bodies[manifolds[ii].body_pair.body2]; SIMD_WIDTH];
+
+        let im1 = SimdFloat::from(array![|ii| rbs1[ii].mass_properties.inv_mass; SIMD_WIDTH]);
+        let ii1: AngularInertia<SimdFloat> =
+            AngularInertia::from(array![|ii| rbs1[ii].world_inv_inertia_sqrt; SIMD_WIDTH]);
+
+        let linvel1 = Vector::from(array![|ii| rbs1[ii].linvel; SIMD_WIDTH]);
+        let angvel1 = AngVector::<SimdFloat>::from(array![|ii| rbs1[ii].angvel; SIMD_WIDTH]);
+
+        let position1 = Isometry::from(array![|ii| rbs1[ii].position; SIMD_WIDTH]);
+
+        let im2 = SimdFloat::from(array![|ii| rbs2[ii].mass_properties.inv_mass; SIMD_WIDTH]);
+        let ii2: AngularInertia<SimdFloat> =
+            AngularInertia::from(array![|ii| rbs2[ii].world_inv_inertia_sqrt; SIMD_WIDTH]);
+
+        let linvel2 = Vector::from(array![|ii| rbs2[ii].linvel; SIMD_WIDTH]);
+        let angvel2 = AngVector::<SimdFloat>::from(array![|ii| rbs2[ii].angvel; SIMD_WIDTH]);
+
+        let position2 = Isometry::from(array![|ii| rbs2[ii].position; SIMD_WIDTH]);
+
+        let force_dir1 = position1 * -Vector::from(array![|ii| manifolds[ii].local_n1; SIMD_WIDTH]);
+
+        let mj_lambda1 = array![|ii| rbs1[ii].active_set_offset; SIMD_WIDTH];
+        let mj_lambda2 = array![|ii| rbs2[ii].active_set_offset; SIMD_WIDTH];
+
+        let friction = SimdFloat::from(array![|ii| manifolds[ii].friction; SIMD_WIDTH]);
+        let warmstart_multiplier =
+            SimdFloat::from(array![|ii| manifolds[ii].warmstart_multiplier; SIMD_WIDTH]);
+        let warmstart_coeff = warmstart_multiplier * SimdFloat::splat(params.warmstart_coeff);
+
+        for l in (0..manifolds[0].num_active_contacts()).step_by(MAX_MANIFOLD_POINTS) {
+            let manifold_points = array![|ii| &manifolds[ii].active_contacts()[l..]; SIMD_WIDTH];
+            let num_points = manifold_points[0].len().min(MAX_MANIFOLD_POINTS);
+
+            let mut constraint = WVelocityConstraint {
+                dir1: force_dir1,
+                elements: [WVelocityConstraintElement::zero(); MAX_MANIFOLD_POINTS],
+                im1,
+                im2,
+                limit: friction,
+                mj_lambda1,
+                mj_lambda2,
+                manifold_id,
+                manifold_contact_id: l,
+                num_contacts: num_points as u8,
+            };
+
+            for k in 0..num_points {
+                // FIXME: can we avoid the multiplications by position1/position2 here?
+                // By working as much as possible in local-space.
+                let p1 = position1
+                    * Point::from(array![|ii| manifold_points[ii][k].local_p1; SIMD_WIDTH]);
+                let p2 = position2
+                    * Point::from(array![|ii| manifold_points[ii][k].local_p2; SIMD_WIDTH]);
+
+                let dist = SimdFloat::from(array![|ii| manifold_points[ii][k].dist; SIMD_WIDTH]);
+
+                let impulse =
+                    SimdFloat::from(array![|ii| manifold_points[ii][k].impulse; SIMD_WIDTH]);
+
+                let dp1 = p1.coords - position1.translation.vector;
+                let dp2 = p2.coords - position2.translation.vector;
+
+                let vel1 = linvel1 + angvel1.gcross(dp1);
+                let vel2 = linvel2 + angvel2.gcross(dp2);
+
+                // Normal part.
+                {
+                    let gcross1 = ii1.transform_vector(dp1.gcross(force_dir1));
+                    let gcross2 = ii2.transform_vector(dp2.gcross(-force_dir1));
+
+                    let r = SimdFloat::splat(1.0)
+                        / (im1 + im2 + gcross1.gdot(gcross1) + gcross2.gdot(gcross2));
+                    let rhs =
+                        (vel1 - vel2).dot(&force_dir1) + dist.simd_max(SimdFloat::zero()) * inv_dt;
+
+                    constraint.elements[k].normal_part = WVelocityConstraintElementPart {
+                        gcross1,
+                        gcross2,
+                        rhs,
+                        impulse: impulse * warmstart_coeff,
+                        r,
+                    };
+                }
+
+                // tangent parts.
+                let tangents1 = force_dir1.orthonormal_basis();
+
+                for j in 0..DIM - 1 {
+                    #[cfg(feature = "dim2")]
+                    let impulse = SimdFloat::from(
+                        array![|ii| manifold_points[ii][k].tangent_impulse; SIMD_WIDTH],
+                    );
+                    #[cfg(feature = "dim3")]
+                    let impulse = SimdFloat::from(
+                        array![|ii| manifold_points[ii][k].tangent_impulse[j]; SIMD_WIDTH],
+                    );
+
+                    let gcross1 = ii1.transform_vector(dp1.gcross(tangents1[j]));
+                    let gcross2 = ii2.transform_vector(dp2.gcross(-tangents1[j]));
+                    let r = SimdFloat::splat(1.0)
+                        / (im1 + im2 + gcross1.gdot(gcross1) + gcross2.gdot(gcross2));
+                    let rhs = (vel1 - vel2).dot(&tangents1[j]);
+
+                    constraint.elements[k].tangent_parts[j] = WVelocityConstraintElementPart {
+                        gcross1,
+                        gcross2,
+                        rhs,
+                        impulse: impulse * warmstart_coeff,
+                        r,
+                    };
+                }
+            }
+
+            if push {
+                out_constraints.push(AnyVelocityConstraint::Grouped(constraint));
+            } else {
+                out_constraints[manifolds[0].constraint_index + l / MAX_MANIFOLD_POINTS] =
+                    AnyVelocityConstraint::Grouped(constraint);
+            }
+        }
+    }
+
+    pub fn warmstart(&self, mj_lambdas: &mut [DeltaVel<f32>]) {
+        let mut mj_lambda1 = DeltaVel {
+            linear: Vector::from(
+                array![|ii| mj_lambdas[self.mj_lambda1[ii] as usize].linear; SIMD_WIDTH],
+            ),
+            angular: AngVector::from(
+                array![|ii| mj_lambdas[self.mj_lambda1[ii] as usize].angular; SIMD_WIDTH],
+            ),
+        };
+
+        let mut mj_lambda2 = DeltaVel {
+            linear: Vector::from(
+                array![|ii| mj_lambdas[self.mj_lambda2[ii] as usize].linear; SIMD_WIDTH],
+            ),
+            angular: AngVector::from(
+                array![|ii| mj_lambdas[self.mj_lambda2[ii] as usize].angular; SIMD_WIDTH],
+            ),
+        };
+
+        for i in 0..self.num_contacts as usize {
+            let elt = &self.elements[i].normal_part;
+            mj_lambda1.linear += self.dir1 * (self.im1 * elt.impulse);
+            mj_lambda1.angular += elt.gcross1 * elt.impulse;
+
+            mj_lambda2.linear += self.dir1 * (-self.im2 * elt.impulse);
+            mj_lambda2.angular += elt.gcross2 * elt.impulse;
+
+            // FIXME: move this out of the for loop?
+            let tangents1 = self.dir1.orthonormal_basis();
+
+            for j in 0..DIM - 1 {
+                let elt = &self.elements[i].tangent_parts[j];
+                mj_lambda1.linear += tangents1[j] * (self.im1 * elt.impulse);
+                mj_lambda1.angular += elt.gcross1 * elt.impulse;
+
+                mj_lambda2.linear += tangents1[j] * (-self.im2 * elt.impulse);
+                mj_lambda2.angular += elt.gcross2 * elt.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<f32>]) {
+        let mut mj_lambda1 = DeltaVel {
+            linear: Vector::from(
+                array![|ii| mj_lambdas[self.mj_lambda1[ii] as usize].linear; SIMD_WIDTH],
+            ),
+            angular: AngVector::from(
+                array![|ii| mj_lambdas[self.mj_lambda1[ii] as usize].angular; SIMD_WIDTH],
+            ),
+        };
+
+        let mut mj_lambda2 = DeltaVel {
+            linear: Vector::from(
+                array![ |ii| mj_lambdas[ self.mj_lambda2[ii] as usize].linear; SIMD_WIDTH],
+            ),
+            angular: AngVector::from(
+                array![ |ii| mj_lambdas[ self.mj_lambda2[ii] as usize].angular; SIMD_WIDTH],
+            ),
+        };
+
+        // Solve friction first.
+        for i in 0..self.num_contacts as usize {
+            // FIXME: move this out of the for loop?
+            let tangents1 = self.dir1.orthonormal_basis();
+            let normal_elt = &self.elements[i].normal_part;
+
+            for j in 0..DIM - 1 {
+                let elt = &mut self.elements[i].tangent_parts[j];
+                let dimpulse = tangents1[j].dot(&mj_lambda1.linear)
+                    + elt.gcross1.gdot(mj_lambda1.angular)
+                    - tangents1[j].dot(&mj_lambda2.linear)
+                    + elt.gcross2.gdot(mj_lambda2.angular)
+                    + elt.rhs;
+                let limit = self.limit * normal_elt.impulse;
+                let new_impulse = (elt.impulse - elt.r * dimpulse).simd_clamp(-limit, limit);
+                let dlambda = new_impulse - elt.impulse;
+                elt.impulse = new_impulse;
+
+                mj_lambda1.linear += tangents1[j] * (self.im1 * dlambda);
+                mj_lambda1.angular += elt.gcross1 * dlambda;
+                mj_lambda2.linear += tangents1[j] * (-self.im2 * dlambda);
+                mj_lambda2.angular += elt.gcross2 * dlambda;
+            }
+        }
+
+        // Solve non-penetration after friction.
+        for i in 0..self.num_contacts as usize {
+            let elt = &mut self.elements[i].normal_part;
+            let dimpulse = self.dir1.dot(&mj_lambda1.linear) + elt.gcross1.gdot(mj_lambda1.angular)
+                - self.dir1.dot(&mj_lambda2.linear)
+                + elt.gcross2.gdot(mj_lambda2.angular)
+                + elt.rhs;
+            let new_impulse = (elt.impulse - elt.r * dimpulse).simd_max(SimdFloat::zero());
+            let dlambda = new_impulse - elt.impulse;
+            elt.impulse = new_impulse;
+
+            mj_lambda1.linear += self.dir1 * (self.im1 * dlambda);
+            mj_lambda1.angular += elt.gcross1 * dlambda;
+            mj_lambda2.linear += self.dir1 * (-self.im2 * dlambda);
+            mj_lambda2.angular += elt.gcross2 * dlambda;
+        }
+
+        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, manifolds_all: &mut [&mut ContactManifold]) {
+        for k in 0..self.num_contacts as usize {
+            let impulses: [_; SIMD_WIDTH] = self.elements[k].normal_part.impulse.into();
+            let tangent_impulses: [_; SIMD_WIDTH] =
+                self.elements[k].tangent_parts[0].impulse.into();
+            #[cfg(feature = "dim3")]
+            let bitangent_impulses: [_; SIMD_WIDTH] =
+                self.elements[k].tangent_parts[1].impulse.into();
+
+            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 = manifold.active_contacts_mut();
+                active_contacts[k_base + k].impulse = impulses[ii];
+
+                #[cfg(feature = "dim2")]
+                {
+                    active_contacts[k_base + k].tangent_impulse = tangent_impulses[ii];
+                }
+                #[cfg(feature = "dim3")]
+                {
+                    active_contacts[k_base + k].tangent_impulse =
+                        [tangent_impulses[ii], bitangent_impulses[ii]];
+                }
+            }
+        }
+    }
+}