diff options
| author | Sébastien Crozet <developer@crozet.re> | 2020-08-25 22:10:25 +0200 |
|---|---|---|
| committer | Sébastien Crozet <developer@crozet.re> | 2020-08-25 22:10:25 +0200 |
| commit | 754a48b7ff6d8c58b1ee08651e60112900b60455 (patch) | |
| tree | 7d777a6c003f1f5d8f8d24f533f35a95a88957fe /src/dynamics/solver/joint_constraint/ball_position_constraint_wide.rs | |
| download | rapier-0.1.0.tar.gz rapier-0.1.0.tar.bz2 rapier-0.1.0.zip | |
First public release of Rapier.v0.1.0
Diffstat (limited to 'src/dynamics/solver/joint_constraint/ball_position_constraint_wide.rs')
| -rw-r--r-- | src/dynamics/solver/joint_constraint/ball_position_constraint_wide.rs | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/src/dynamics/solver/joint_constraint/ball_position_constraint_wide.rs b/src/dynamics/solver/joint_constraint/ball_position_constraint_wide.rs new file mode 100644 index 0000000..c552d57 --- /dev/null +++ b/src/dynamics/solver/joint_constraint/ball_position_constraint_wide.rs @@ -0,0 +1,199 @@ +use crate::dynamics::{BallJoint, IntegrationParameters, RigidBody}; +#[cfg(feature = "dim2")] +use crate::math::SdpMatrix; +use crate::math::{AngularInertia, Isometry, Point, Rotation, SimdFloat, SIMD_WIDTH}; +use crate::utils::{WAngularInertia, WCross, WCrossMatrix}; +use simba::simd::SimdValue; + +#[derive(Debug)] +pub(crate) struct WBallPositionConstraint { + position1: [usize; SIMD_WIDTH], + position2: [usize; SIMD_WIDTH], + + local_com1: Point<SimdFloat>, + local_com2: Point<SimdFloat>, + + im1: SimdFloat, + im2: SimdFloat, + + ii1: AngularInertia<SimdFloat>, + ii2: AngularInertia<SimdFloat>, + + local_anchor1: Point<SimdFloat>, + local_anchor2: Point<SimdFloat>, +} + +impl WBallPositionConstraint { + pub fn from_params( + rbs1: [&RigidBody; SIMD_WIDTH], + rbs2: [&RigidBody; SIMD_WIDTH], + cparams: [&BallJoint; SIMD_WIDTH], + ) -> Self { + let local_com1 = Point::from(array![|ii| rbs1[ii].mass_properties.local_com; SIMD_WIDTH]); + let local_com2 = Point::from(array![|ii| rbs2[ii].mass_properties.local_com; SIMD_WIDTH]); + let im1 = SimdFloat::from(array![|ii| rbs1[ii].mass_properties.inv_mass; SIMD_WIDTH]); + let im2 = SimdFloat::from(array![|ii| rbs2[ii].mass_properties.inv_mass; SIMD_WIDTH]); + let ii1 = AngularInertia::<SimdFloat>::from( + array![|ii| rbs1[ii].world_inv_inertia_sqrt; SIMD_WIDTH], + ) + .squared(); + let ii2 = AngularInertia::<SimdFloat>::from( + array![|ii| rbs2[ii].world_inv_inertia_sqrt; SIMD_WIDTH], + ) + .squared(); + let local_anchor1 = Point::from(array![|ii| cparams[ii].local_anchor1; SIMD_WIDTH]); + let local_anchor2 = Point::from(array![|ii| cparams[ii].local_anchor2; SIMD_WIDTH]); + let position1 = array![|ii| rbs1[ii].active_set_offset; SIMD_WIDTH]; + let position2 = array![|ii| rbs2[ii].active_set_offset; SIMD_WIDTH]; + + Self { + local_com1, + local_com2, + im1, + im2, + ii1, + ii2, + local_anchor1, + local_anchor2, + position1, + position2, + } + } + + pub fn solve(&self, params: &IntegrationParameters, positions: &mut [Isometry<f32>]) { + let mut position1 = Isometry::from(array![|ii| positions[self.position1[ii]]; SIMD_WIDTH]); + let mut position2 = Isometry::from(array![|ii| positions[self.position2[ii]]; SIMD_WIDTH]); + + let anchor1 = position1 * self.local_anchor1; + let anchor2 = position2 * self.local_anchor2; + + let com1 = position1 * self.local_com1; + let com2 = position2 * self.local_com2; + + let err = anchor1 - anchor2; + + let centered_anchor1 = anchor1 - com1; + let centered_anchor2 = anchor2 - com2; + + let cmat1 = centered_anchor1.gcross_matrix(); + let cmat2 = centered_anchor2.gcross_matrix(); + + // NOTE: the -cmat1 is just a simpler way of doing cmat1.transpose() + // because it is anti-symmetric. + #[cfg(feature = "dim3")] + let lhs = self.ii1.quadform(&cmat1).add_diagonal(self.im1) + + self.ii2.quadform(&cmat2).add_diagonal(self.im2); + + // In 2D we just unroll the computation because + // it's just easier that way. + #[cfg(feature = "dim2")] + let lhs = { + let m11 = + self.im1 + self.im2 + cmat1.x * cmat1.x * self.ii1 + cmat2.x * cmat2.x * self.ii2; + let m12 = cmat1.x * cmat1.y * self.ii1 + cmat2.x * cmat2.y * self.ii2; + let m22 = + self.im1 + self.im2 + cmat1.y * cmat1.y * self.ii1 + cmat2.y * cmat2.y * self.ii2; + SdpMatrix::new(m11, m12, m22) + }; + + let inv_lhs = lhs.inverse_unchecked(); + let impulse = inv_lhs * -(err * SimdFloat::splat(params.joint_erp)); + + position1.translation.vector += impulse * self.im1; + position2.translation.vector -= impulse * self.im2; + + let angle1 = self.ii1.transform_vector(centered_anchor1.gcross(impulse)); + let angle2 = self.ii2.transform_vector(centered_anchor2.gcross(-impulse)); + + position1.rotation = Rotation::new(angle1) * position1.rotation; + position2.rotation = Rotation::new(angle2) * position2.rotation; + + for ii in 0..SIMD_WIDTH { + positions[self.position1[ii]] = position1.extract(ii); + } + for ii in 0..SIMD_WIDTH { + positions[self.position2[ii]] = position2.extract(ii); + } + } +} + +#[derive(Debug)] +pub(crate) struct WBallPositionGroundConstraint { + position2: [usize; SIMD_WIDTH], + anchor1: Point<SimdFloat>, + im2: SimdFloat, + ii2: AngularInertia<SimdFloat>, + local_anchor2: Point<SimdFloat>, + local_com2: Point<SimdFloat>, +} + +impl WBallPositionGroundConstraint { + pub fn from_params( + rbs1: [&RigidBody; SIMD_WIDTH], + rbs2: [&RigidBody; SIMD_WIDTH], + cparams: [&BallJoint; SIMD_WIDTH], + flipped: [bool; SIMD_WIDTH], + ) -> Self { + let position1 = Isometry::from(array![|ii| rbs1[ii].predicted_position; SIMD_WIDTH]); + let anchor1 = position1 + * Point::from(array![|ii| if flipped[ii] { + cparams[ii].local_anchor2 + } else { + cparams[ii].local_anchor1 + }; SIMD_WIDTH]); + let im2 = SimdFloat::from(array![|ii| rbs2[ii].mass_properties.inv_mass; SIMD_WIDTH]); + let ii2 = AngularInertia::<SimdFloat>::from( + array![|ii| rbs2[ii].world_inv_inertia_sqrt; SIMD_WIDTH], + ) + .squared(); + let local_anchor2 = Point::from(array![|ii| if flipped[ii] { + cparams[ii].local_anchor1 + } else { + cparams[ii].local_anchor2 + }; SIMD_WIDTH]); + let position2 = array![|ii| rbs2[ii].active_set_offset; SIMD_WIDTH]; + let local_com2 = Point::from(array![|ii| rbs2[ii].mass_properties.local_com; SIMD_WIDTH]); + + Self { + anchor1, + im2, + ii2, + local_anchor2, + position2, + local_com2, + } + } + + pub fn solve(&self, params: &IntegrationParameters, positions: &mut [Isometry<f32>]) { + let mut position2 = Isometry::from(array![|ii| positions[self.position2[ii]]; SIMD_WIDTH]); + + let anchor2 = position2 * self.local_anchor2; + let com2 = position2 * self.local_com2; + + let err = self.anchor1 - anchor2; + let centered_anchor2 = anchor2 - com2; + let cmat2 = centered_anchor2.gcross_matrix(); + + #[cfg(feature = "dim3")] + let lhs = self.ii2.quadform(&cmat2).add_diagonal(self.im2); + + #[cfg(feature = "dim2")] + let lhs = { + let m11 = self.im2 + cmat2.x * cmat2.x * self.ii2; + let m12 = cmat2.x * cmat2.y * self.ii2; + let m22 = self.im2 + cmat2.y * cmat2.y * self.ii2; + SdpMatrix::new(m11, m12, m22) + }; + + let inv_lhs = lhs.inverse_unchecked(); + let impulse = inv_lhs * -(err * SimdFloat::splat(params.joint_erp)); + position2.translation.vector -= impulse * self.im2; + + let angle2 = self.ii2.transform_vector(centered_anchor2.gcross(-impulse)); + position2.rotation = Rotation::new(angle2) * position2.rotation; + + for ii in 0..SIMD_WIDTH { + positions[self.position2[ii]] = position2.extract(ii); + } + } +} |
