Run the position solver after the CCD motion clamping.

This commit is contained in:
Crozet Sébastien
2021-03-30 17:11:52 +02:00
parent d2ee642053
commit 88933bd431
6 changed files with 142 additions and 98 deletions

View File

@@ -24,7 +24,25 @@ impl IslandSolver {
}
}
pub fn solve_island(
pub fn solve_position_constraints(
&mut self,
island_id: usize,
counters: &mut Counters,
params: &IntegrationParameters,
bodies: &mut RigidBodySet,
) {
counters.solver.position_resolution_time.resume();
self.position_solver.solve(
island_id,
params,
bodies,
&self.contact_constraints.position_constraints,
&self.joint_constraints.position_constraints,
);
counters.solver.position_resolution_time.pause();
}
pub fn init_constraints_and_solve_velocity_constraints(
&mut self,
island_id: usize,
counters: &mut Counters,
@@ -62,17 +80,9 @@ impl IslandSolver {
rb.integrate_next_position(params.dt, true)
});
counters.solver.velocity_update_time.pause();
counters.solver.position_resolution_time.resume();
self.position_solver.solve(
island_id,
params,
bodies,
&self.contact_constraints.position_constraints,
&self.joint_constraints.position_constraints,
);
counters.solver.position_resolution_time.pause();
} else {
self.contact_constraints.clear();
self.joint_constraints.clear();
counters.solver.velocity_update_time.resume();
bodies.foreach_active_island_body_mut_internal(island_id, |_, rb| {
// Since we didn't run the velocity solver we need to integrate the accelerations here

View File

@@ -200,11 +200,9 @@ impl ParallelIslandSolver {
let dvel = &mut self.mj_lambdas[rb.active_set_offset];
dvel.linear += rb.force * (rb.effective_inv_mass * params.dt);
rb.force = na::zero();
// dvel.angular is actually storing angular velocity delta multiplied by the square root of the inertia tensor:
dvel.angular += rb.effective_world_inv_inertia_sqrt * rb.torque * params.dt;
rb.torque = na::zero();
}
}
}

View File

@@ -21,6 +21,11 @@ impl PositionSolver {
contact_constraints: &[AnyPositionConstraint],
joint_constraints: &[AnyJointPositionConstraint],
) {
if contact_constraints.is_empty() && joint_constraints.is_empty() {
// Nothing to do.
return;
}
self.positions.clear();
self.positions.extend(
bodies

View File

@@ -38,6 +38,15 @@ impl<VelocityConstraint, PositionConstraint>
position_constraints: Vec::new(),
}
}
pub fn clear(&mut self) {
self.not_ground_interactions.clear();
self.ground_interactions.clear();
self.interaction_groups.clear();
self.ground_interaction_groups.clear();
self.velocity_constraints.clear();
self.position_constraints.clear();
}
}
impl SolverConstraints<AnyVelocityConstraint, AnyPositionConstraint> {

View File

@@ -58,7 +58,7 @@ impl PhysicsPipeline {
}
}
fn detect_collisions_after_user_modifications(
fn detect_collisions(
&mut self,
integration_parameters: &IntegrationParameters,
broad_phase: &mut BroadPhase,
@@ -67,6 +67,7 @@ impl PhysicsPipeline {
colliders: &mut ColliderSet,
hooks: &dyn PhysicsHooks,
events: &dyn EventHandler,
handle_user_changes: bool,
) {
self.counters.stages.collision_detection_time.resume();
self.counters.cd.broad_phase_time.resume();
@@ -84,7 +85,9 @@ impl PhysicsPipeline {
self.counters.cd.narrow_phase_time.resume();
// Update narrow-phase.
narrow_phase.handle_user_changes(colliders, bodies, events);
if handle_user_changes {
narrow_phase.handle_user_changes(colliders, bodies, events);
}
narrow_phase.register_pairs(colliders, bodies, &self.broad_phase_events, events);
narrow_phase.compute_contacts(
integration_parameters.prediction_distance,
@@ -102,51 +105,27 @@ impl PhysicsPipeline {
self.counters.stages.collision_detection_time.pause();
}
fn detect_collisions_after_integration(
fn solve_position_constraints(
&mut self,
integration_parameters: &IntegrationParameters,
broad_phase: &mut BroadPhase,
narrow_phase: &mut NarrowPhase,
bodies: &mut RigidBodySet,
colliders: &mut ColliderSet,
hooks: &dyn PhysicsHooks,
events: &dyn EventHandler,
) {
self.counters.stages.collision_detection_time.resume();
self.counters.cd.broad_phase_time.resume();
#[cfg(not(feature = "parallel"))]
{
enable_flush_to_zero!();
// Update broad-phase.
self.broad_phase_events.clear();
self.broadphase_collider_pairs.clear();
broad_phase.update(
integration_parameters.prediction_distance,
colliders,
&mut self.broad_phase_events,
);
self.counters.cd.broad_phase_time.pause();
self.counters.cd.narrow_phase_time.resume();
// Update narrow-phase.
// NOTE: we don't need to call `narrow_phase.handle_user_changes` because this
// has already been done at the beginning of the timestep.
narrow_phase.register_pairs(colliders, bodies, &self.broad_phase_events, events);
narrow_phase.compute_contacts(
integration_parameters.prediction_distance,
bodies,
colliders,
hooks,
events,
);
narrow_phase.compute_intersections(bodies, colliders, hooks, events);
// Clear colliders modification flags.
colliders.clear_modified_colliders();
self.counters.cd.narrow_phase_time.pause();
self.counters.stages.collision_detection_time.pause();
for island_id in 0..bodies.num_islands() {
self.solvers[island_id].solve_position_constraints(
island_id,
&mut self.counters,
integration_parameters,
bodies,
)
}
}
}
fn build_islands_and_solve_constraints(
fn build_islands_and_solve_velocity_constraints(
&mut self,
gravity: &Vector<Real>,
integration_parameters: &IntegrationParameters,
@@ -196,7 +175,7 @@ impl PhysicsPipeline {
enable_flush_to_zero!();
for island_id in 0..bodies.num_islands() {
self.solvers[island_id].solve_island(
self.solvers[island_id].init_constraints_and_solve_velocity_constraints(
island_id,
&mut self.counters,
integration_parameters,
@@ -246,6 +225,7 @@ impl PhysicsPipeline {
&manifold_indices[island_id],
joints,
&joint_constraint_indices[island_id],
is_last_substep,
)
});
});
@@ -258,23 +238,28 @@ impl PhysicsPipeline {
integration_parameters: &IntegrationParameters,
bodies: &mut RigidBodySet,
colliders: &mut ColliderSet,
narrow_phase: &NarrowPhase,
ccd_solver: &mut CCDSolver,
events: &dyn EventHandler,
) {
self.counters.ccd.toi_computation_time.start();
// Handle CCD
let impacts = ccd_solver.predict_impacts_at_next_positions(
integration_parameters.dt,
bodies,
colliders,
narrow_phase,
events,
);
ccd_solver.clamp_motions(integration_parameters.dt, bodies, &impacts);
self.counters.ccd.toi_computation_time.pause();
}
fn advance_to_final_positions(
&mut self,
bodies: &mut RigidBodySet,
colliders: &mut ColliderSet,
clear_forces: bool,
) {
// Set the rigid-bodies and kinematic bodies to their final position.
bodies.foreach_active_body_mut_internal(|_, rb| {
@@ -283,6 +268,11 @@ impl PhysicsPipeline {
rb.angvel = na::zero();
}
if clear_forces {
rb.force = na::zero();
rb.torque = na::zero();
}
rb.position = rb.next_position;
rb.update_colliders_positions(colliders);
});
@@ -322,7 +312,7 @@ impl PhysicsPipeline {
colliders.handle_user_changes(bodies);
bodies.handle_user_changes(colliders);
self.detect_collisions_after_user_modifications(
self.detect_collisions(
integration_parameters,
broad_phase,
narrow_phase,
@@ -330,23 +320,41 @@ impl PhysicsPipeline {
colliders,
hooks,
events,
true,
);
let mut remaining_time = integration_parameters.dt;
let mut remaining_substeps = integration_parameters.max_ccd_substeps;
let mut integration_parameters = *integration_parameters;
let ccd_active = ccd_solver.update_ccd_active_flags(bodies, integration_parameters.dt);
let (ccd_is_enabled, mut remaining_substeps) =
if integration_parameters.max_ccd_substeps == 0 {
(false, 1)
} else {
(true, integration_parameters.max_ccd_substeps)
};
loop {
if ccd_active && remaining_substeps > 1 {
// If there are more than one CCD substep, we need to split
// the timestep into multiple intervals. First, estimate the
// size of the time slice we will integrate for this substep.
//
// If there is only one or zero CCD substep, there is no need
// to split the timetsep interval. So we can just skip this part.
if let Some(toi) = ccd_solver.find_first_impact(remaining_time, bodies, colliders) {
while remaining_substeps > 0 {
// If there are more than one CCD substep, we need to split
// the timestep into multiple intervals. First, estimate the
// size of the time slice we will integrate for this substep.
//
// Note that we must do this now, before the constrains resolution
// because we need to use the correct timestep length for the
// integration of external forces.
//
// If there is only one or zero CCD substep, there is no need
// to split the timetsep interval. So we can just skip this part.
if ccd_is_enabled && remaining_substeps > 1 {
// NOTE: Take forces into account when updating the bodies CCD activation flags
// these forces have not been integrated to the body's velocity yet.
let ccd_active = ccd_solver.update_ccd_active_flags(bodies, remaining_time, true);
let first_impact = if ccd_active {
ccd_solver.find_first_impact(remaining_time, bodies, colliders, narrow_phase)
} else {
None
};
if let Some(toi) = first_impact {
let original_interval = remaining_time / (remaining_substeps as Real);
if toi < original_interval {
@@ -360,7 +368,7 @@ impl PhysicsPipeline {
} else {
// No impact, don't do any other substep after this one.
integration_parameters.dt = remaining_time;
remaining_substeps = 1;
remaining_substeps = 0;
}
remaining_time -= integration_parameters.dt;
@@ -368,16 +376,18 @@ impl PhysicsPipeline {
// Avoid substep length that are too small.
if remaining_time <= integration_parameters.min_ccd_dt {
integration_parameters.dt += remaining_time;
remaining_substeps = 1;
remaining_substeps = 0;
}
} else {
integration_parameters.dt = remaining_time;
remaining_time = 0.0;
remaining_substeps = 1;
remaining_substeps = 0;
}
self.counters.ccd.num_substeps += 1;
self.interpolate_kinematic_velocities(&integration_parameters, bodies);
self.build_islands_and_solve_constraints(
self.build_islands_and_solve_velocity_constraints(
gravity,
&integration_parameters,
narrow_phase,
@@ -387,18 +397,35 @@ impl PhysicsPipeline {
);
// If CCD is enabled, execute the CCD motion clamping.
if ccd_active && remaining_substeps > 0 {
self.run_ccd_motion_clamping(
&integration_parameters,
bodies,
colliders,
ccd_solver,
events,
);
if ccd_is_enabled {
// NOTE: don't the forces into account when updating the CCD active flags because
// they have already been integrated into the velocities by the solver.
let ccd_active =
ccd_solver.update_ccd_active_flags(bodies, integration_parameters.dt, false);
if ccd_active {
self.run_ccd_motion_clamping(
&integration_parameters,
bodies,
colliders,
narrow_phase,
ccd_solver,
events,
);
}
}
self.advance_to_final_positions(bodies, colliders);
self.detect_collisions_after_integration(
// NOTE: we need to run the position solver **after** the
// CCD motion clamping because otherwise the clamping
// would undo the depenetration done by the position
// solver.
// This happens because our CCD use the real rigid-body
// velocities instead of just interpolating between
// isometries.
self.solve_position_constraints(&integration_parameters, bodies);
let clear_forces = remaining_substeps == 0;
self.advance_to_final_positions(bodies, colliders, clear_forces);
self.detect_collisions(
&integration_parameters,
broad_phase,
narrow_phase,
@@ -406,15 +433,12 @@ impl PhysicsPipeline {
colliders,
hooks,
events,
false,
);
bodies.modified_inactive_set.clear();
if !ccd_active || remaining_substeps <= 1 {
// We executed all the substeps.
break;
}
}
self.counters.step_completed();
}
}