From f9e3d382d2ee097dce05997735982f5e120cca03 Mon Sep 17 00:00:00 2001 From: Emil Ernerfeldt Date: Mon, 15 Feb 2021 21:18:26 +0100 Subject: New contacts are bouncy, old are resting If a contact is new (previous impluse = 0), then we treat it as bouncy (respecting restitution). If the contact is old we treat it as resting. Exceptions for restitutions <=0 and >= 1. --- src/dynamics/solver/velocity_constraint_wide.rs | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) (limited to 'src/dynamics/solver/velocity_constraint_wide.rs') diff --git a/src/dynamics/solver/velocity_constraint_wide.rs b/src/dynamics/solver/velocity_constraint_wide.rs index a8384de..bd7fdcf 100644 --- a/src/dynamics/solver/velocity_constraint_wide.rs +++ b/src/dynamics/solver/velocity_constraint_wide.rs @@ -2,7 +2,8 @@ use super::{AnyVelocityConstraint, DeltaVel}; use crate::dynamics::{IntegrationParameters, RigidBodySet}; use crate::geometry::{ContactManifold, ContactManifoldIndex}; use crate::math::{ - AngVector, AngularInertia, Point, Real, SimdReal, Vector, DIM, MAX_MANIFOLD_POINTS, SIMD_WIDTH, + AngVector, AngularInertia, Point, Real, SimdBool, SimdReal, Vector, DIM, MAX_MANIFOLD_POINTS, + SIMD_WIDTH, }; use crate::utils::{WAngularInertia, WBasis, WCross, WDot}; use num::Zero; @@ -96,8 +97,6 @@ impl WVelocityConstraint { 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 restitution_velocity_threshold = SimdReal::splat(params.restitution_velocity_threshold); - let warmstart_multiplier = SimdReal::from(array![|ii| manifolds[ii].data.warmstart_multiplier; SIMD_WIDTH]); let warmstart_coeff = warmstart_multiplier * SimdReal::splat(params.warmstart_coeff); @@ -125,8 +124,11 @@ impl WVelocityConstraint { for k in 0..num_points { let friction = SimdReal::from(array![|ii| manifold_points[ii][k].friction; SIMD_WIDTH]); - let restitution = - SimdReal::from(array![|ii| manifold_points[ii][k].restitution; SIMD_WIDTH]); + let restitution_plus_1 = SimdReal::from( + array![|ii| manifold_points[ii][k].restitution + 1.0; SIMD_WIDTH], + ); + let is_bouncy = + SimdBool::from(array![|ii| manifold_points[ii][k].is_bouncy(); SIMD_WIDTH]); let point = Point::from(array![|ii| manifold_points[ii][k].point; SIMD_WIDTH]); let dist = SimdReal::from(array![|ii| manifold_points[ii][k].dist; SIMD_WIDTH]); @@ -148,11 +150,10 @@ impl WVelocityConstraint { let r = SimdReal::splat(1.0) / (im1 + im2 + gcross1.gdot(gcross1) + gcross2.gdot(gcross2)); - let mut rhs = (vel1 - vel2).dot(&force_dir1); - let use_restitution = rhs.simd_le(-restitution_velocity_threshold); - let rhs_with_restitution = rhs + rhs * restitution; - rhs = rhs_with_restitution.select(use_restitution, rhs); - rhs += dist.simd_max(SimdReal::zero()) * inv_dt; + let projected_velocity = (vel1 - vel2).dot(&force_dir1); + let rhs_resting = projected_velocity + dist.simd_max(SimdReal::zero()) * inv_dt; + let rhs_bouncing = projected_velocity * restitution_plus_1; + let rhs = rhs_bouncing.select(is_bouncy, rhs_resting); constraint.elements[k].normal_part = WVelocityConstraintElementPart { gcross1, -- cgit From 5e7eedc3fdf74b49ecd999b003570bf352ee3f11 Mon Sep 17 00:00:00 2001 From: Emil Ernerfeldt Date: Thu, 18 Feb 2021 17:58:17 +0100 Subject: Always apply the predictive contact term, even for bouncing contacts --- src/dynamics/solver/velocity_constraint_wide.rs | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) (limited to 'src/dynamics/solver/velocity_constraint_wide.rs') diff --git a/src/dynamics/solver/velocity_constraint_wide.rs b/src/dynamics/solver/velocity_constraint_wide.rs index bd7fdcf..3e068e7 100644 --- a/src/dynamics/solver/velocity_constraint_wide.rs +++ b/src/dynamics/solver/velocity_constraint_wide.rs @@ -2,8 +2,7 @@ use super::{AnyVelocityConstraint, DeltaVel}; use crate::dynamics::{IntegrationParameters, RigidBodySet}; use crate::geometry::{ContactManifold, ContactManifoldIndex}; use crate::math::{ - AngVector, AngularInertia, Point, Real, SimdBool, SimdReal, Vector, DIM, MAX_MANIFOLD_POINTS, - SIMD_WIDTH, + AngVector, AngularInertia, Point, Real, SimdReal, Vector, DIM, MAX_MANIFOLD_POINTS, SIMD_WIDTH, }; use crate::utils::{WAngularInertia, WBasis, WCross, WDot}; use num::Zero; @@ -124,11 +123,11 @@ impl WVelocityConstraint { for k in 0..num_points { let friction = SimdReal::from(array![|ii| manifold_points[ii][k].friction; SIMD_WIDTH]); - let restitution_plus_1 = SimdReal::from( - array![|ii| manifold_points[ii][k].restitution + 1.0; SIMD_WIDTH], + let restitution = + SimdReal::from(array![|ii| manifold_points[ii][k].restitution; SIMD_WIDTH]); + let is_bouncy = SimdReal::from( + array![|ii| manifold_points[ii][k].is_bouncy() as u32 as Real; SIMD_WIDTH], ); - let is_bouncy = - SimdBool::from(array![|ii| manifold_points[ii][k].is_bouncy(); SIMD_WIDTH]); let point = Point::from(array![|ii| manifold_points[ii][k].point; SIMD_WIDTH]); let dist = SimdReal::from(array![|ii| manifold_points[ii][k].dist; SIMD_WIDTH]); @@ -151,9 +150,8 @@ impl WVelocityConstraint { let r = SimdReal::splat(1.0) / (im1 + im2 + gcross1.gdot(gcross1) + gcross2.gdot(gcross2)); let projected_velocity = (vel1 - vel2).dot(&force_dir1); - let rhs_resting = projected_velocity + dist.simd_max(SimdReal::zero()) * inv_dt; - let rhs_bouncing = projected_velocity * restitution_plus_1; - let rhs = rhs_bouncing.select(is_bouncy, rhs_resting); + let rhs = (SimdReal::splat(1.0) + is_bouncy * restitution) * projected_velocity + + dist.simd_max(SimdReal::zero()) * inv_dt; constraint.elements[k].normal_part = WVelocityConstraintElementPart { gcross1, -- cgit