VBD integrator [2]. More...

Inheritance diagram for pbat::gpu::impl::vbd::Integrator:

Public Types
using	EInitializationStrategy
	Enum type for initialization strategy.

using	Data = pbat::sim::vbd::Data
	Data type for VBD.

Public Member Functions
	Integrator (Data const &data)
	Construct Integrator from data.

void	Step (GpuScalar dt, GpuIndex iterations, GpuIndex substeps=GpuIndex{1})
	Execute one simulation step.

void	TracedStep (GpuScalar dt, GpuIndex iterations, GpuIndex substeps, GpuIndex t, std::string_view dir=".")
	Execute one simulation step with tracing to disk.

void	SetSceneBoundingBox (Eigen::Vector< GpuScalar, 3 > const &min, Eigen::Vector< GpuScalar, 3 > const &max)
	Set the bounding box over the scene used for spatial partitioning.

void	SetBlockSize (GpuIndex blockSize)
	Set the number of threads per GPU block for per-vertex elastic energy computation.

void	InitializeActiveSet (GpuScalar dt)
	Detect candidate contact pairs for the current time step.

void	ComputeInertialTargets (GpuScalar sdt, GpuScalar sdt2)
	Compute the inertial target positions of the BDF1 objective.

void	InitializeBcdSolution (GpuScalar sdt, GpuScalar sdt2)
	Compute starting point of BCD minimization.

void	UpdateActiveSet ()
	Computes active contact pairs in the current configuration.

virtual void	Solve (kernels::BackwardEulerMinimization &bdf, GpuIndex iterations)
	VBD to iterate on the BDF minimization problem.

void	TracedSolve (kernels::BackwardEulerMinimization &bdf, GpuIndex iterations, GpuIndex t, GpuIndex s, std::string_view dir)
	VBD to iterate on the BDF minimization problem.

void	RunVbdIteration (kernels::BackwardEulerMinimization &bdf)
	Run a single iteration of the VBD's BDF minimization.

void	UpdateBdfState (GpuScalar sdt)
	Update the BDF state (i.e. positions and velocities) after solving the BDF minimization.

kernels::BackwardEulerMinimization	BdfDeviceParameters (GpuScalar dt, GpuScalar dt2)
	Obtain Backward Euler time stepping minimization problem for device code.

Public Attributes
common::Buffer< GpuScalar, 3 >	x
	Vertex positions.

common::Buffer< GpuIndex, 4 >	T
	Tetrahedral mesh elements.

Eigen::Vector< GpuScalar, 3 >	mWorldMin
	World AABB min.

Eigen::Vector< GpuScalar, 3 >	mWorldMax
	World AABB max.

GpuIndex	mActiveSetUpdateFrequency
	Active set update frequency.

contact::VertexTriangleMixedCcdDcd	cd
	Collision detector.

common::Buffer< GpuIndex >	fc

common::Buffer< GpuScalar >	XVA
	`\|x.Size()\|` array of vertex areas for contact response

common::Buffer< GpuScalar >	FA
	`\|F.Size()\|` array of triangle areas for contact response

common::Buffer< GpuScalar, 3 >	mPositionsAtT
	Previous vertex positions.

common::Buffer< GpuScalar, 3 >	mInertialTargetPositions
	Inertial target for vertex positions.

common::Buffer< GpuScalar, 3 >	xb
	Write buffer for positions which handles data races.

common::Buffer< GpuScalar, 3 >	mVelocitiesAtT
	Previous vertex velocities.

common::Buffer< GpuScalar, 3 >	mVelocities
	Current vertex velocities.

common::Buffer< GpuScalar, 3 >	mExternalAcceleration
	External acceleration.

common::Buffer< GpuScalar >	mMass
	Lumped mass matrix diagonals.

common::Buffer< GpuScalar >	mQuadratureWeights

common::Buffer< GpuScalar >	mShapeFunctionGradients
	`4x3x\|# elements\|` shape function gradients

common::Buffer< GpuScalar >	mLameCoefficients
	`2x\|# elements\|` 1st and 2nd Lame parameters

GpuScalar	mDetHZero
	Numerical zero for hessian determinant check.

common::Buffer< GpuIndex >	mVertexTetrahedronPrefix
	Vertex-tetrahedron adjacency list's prefix sum.

common::Buffer< GpuIndex >	mVertexTetrahedronNeighbours
	Vertex-tetrahedron adjacency list's neighbour list.

common::Buffer< GpuIndex >	mVertexTetrahedronLocalVertexIndices

GpuScalar	mRayleighDamping
	Rayleigh damping coefficient.

GpuScalar	mCollisionPenalty
	Collision penalty coefficient.

GpuScalar	mFrictionCoefficient
	Coefficient of friction.

GpuScalar	mSmoothFrictionRelativeVelocityThreshold

GpuIndexVectorX	mPptr

common::Buffer< GpuIndex >	mPadj
	Partition vertices.

EInitializationStrategy	mInitializationStrategy
	Strategy to use to determine the initial BCD iterate.

GpuIndex	mGpuThreadBlockSize
	Number of threads per CUDA thread block.

cuda::stream_t	mStream
	Cuda stream on which this VBD instance will run.

Detailed Description

VBD integrator [2].

Member Typedef Documentation

◆ EInitializationStrategy

using pbat::gpu::impl::vbd::Integrator::EInitializationStrategy

Initial value:

pbat::sim::vbd::EInitializationStrategy

EInitializationStrategy

Initialization strategies for the VBD time step minimization.

Definition Enums.h:9

Enum type for initialization strategy.

Constructor & Destructor Documentation

◆ Integrator()

pbat::gpu::impl::vbd::Integrator::Integrator ( Data const & data )

Construct Integrator from data.

Parameters

data	VBD simulation scenario

Member Function Documentation

◆ BdfDeviceParameters()

kernels::BackwardEulerMinimization pbat::gpu::impl::vbd::Integrator::BdfDeviceParameters	(	GpuScalar	dt,
		GpuScalar	dt2 )

Obtain Backward Euler time stepping minimization problem for device code.

Parameters

dt	Time step
dt2	Time step squared

Returns: Backward Euler minimization problem for device code

◆ ComputeInertialTargets()

void pbat::gpu::impl::vbd::Integrator::ComputeInertialTargets	(	GpuScalar	sdt,
		GpuScalar	sdt2 )

Compute the inertial target positions of the BDF1 objective.

Parameters

sdt	Time step
sdt2	Time step squared

◆ InitializeActiveSet()

void pbat::gpu::impl::vbd::Integrator::InitializeActiveSet ( GpuScalar dt )

Detect candidate contact pairs for the current time step.

Parameters

dt Time step

◆ InitializeBcdSolution()

void pbat::gpu::impl::vbd::Integrator::InitializeBcdSolution	(	GpuScalar	sdt,
		GpuScalar	sdt2 )

Compute starting point of BCD minimization.

Parameters

sdt	Time step
sdt2	Time step squared

◆ RunVbdIteration()

void pbat::gpu::impl::vbd::Integrator::RunVbdIteration ( kernels::BackwardEulerMinimization & bdf )

Run a single iteration of the VBD's BDF minimization.

Parameters

bdf	Device BDF minimization problem

◆ SetBlockSize()

void pbat::gpu::impl::vbd::Integrator::SetBlockSize ( GpuIndex blockSize )

Set the number of threads per GPU block for per-vertex elastic energy computation.

Parameters

blockSize Number of threads per block

◆ SetSceneBoundingBox()

void pbat::gpu::impl::vbd::Integrator::SetSceneBoundingBox	(	Eigen::Vector< GpuScalar, 3 > const &	min,
		Eigen::Vector< GpuScalar, 3 > const &	max )

Set the bounding box over the scene used for spatial partitioning.

Parameters

min	Minimum corner
max	Maximum corner

◆ Solve()

void pbat::gpu::impl::vbd::Integrator::Solve	(	kernels::BackwardEulerMinimization &	bdf,
		GpuIndex	iterations )

virtual

VBD to iterate on the BDF minimization problem.

Override this method to implement different VBD optimization strategies

Parameters

bdf	Device BDF minimization problem
iterations	Number of iterations

Reimplemented in pbat::gpu::impl::vbd::AndersonIntegrator, pbat::gpu::impl::vbd::ChebyshevIntegrator, and pbat::gpu::impl::vbd::TrustRegionIntegrator.

◆ Step()

void pbat::gpu::impl::vbd::Integrator::Step	(	GpuScalar	dt,
		GpuIndex	iterations,
		GpuIndex	substeps = GpuIndex{1} )

Execute one simulation step.

Parameters

dt	Time step
iterations	Number of optimization iterations per substep
substeps	Number of substeps

◆ TracedSolve()

void pbat::gpu::impl::vbd::Integrator::TracedSolve	(	kernels::BackwardEulerMinimization &	bdf,
		GpuIndex	iterations,
		GpuIndex	t,
		GpuIndex	s,
		std::string_view	dir )

VBD to iterate on the BDF minimization problem.

Saves all iterates to disk.

Parameters

bdf	Device BDF minimization problem
iterations	Number of iterations
t	Current time step
s	Current substep
dir	Directory to save matrix market files

◆ TracedStep()

void pbat::gpu::impl::vbd::Integrator::TracedStep	(	GpuScalar	dt,
		GpuIndex	iterations,
		GpuIndex	substeps,
		GpuIndex	t,
		std::string_view	dir = "." )

Execute one simulation step with tracing to disk.

Saves matrix market files which follow the pattern {variable}.t.{timestep}.s.{substep}[.k.{iteration}].mtx

Parameters

dt	Time step
iterations	Number of optimization iterations per substep
substeps	Number of substeps
t	Current time step
dir	Directory to save matrix market files

◆ UpdateBdfState()

void pbat::gpu::impl::vbd::Integrator::UpdateBdfState ( GpuScalar sdt )

Update the BDF state (i.e. positions and velocities) after solving the BDF minimization.

Parameters

sdt Time step

Member Data Documentation

◆ fc

common::Buffer<GpuIndex> pbat::gpu::impl::vbd::Integrator::fc

|# verts * kMaxCollidingTrianglesPerVertex| array of vertex-triangle contact pairs (i,f), s.t. f = fc[i*kMaxCollidingTrianglesPerVertex+c] for 0 <= c < /< kMaxCollidingTrianglesPerVertex. If f(c) < 0, there is no contact, and f(c+j) < /< 0 is also true, for j > 0.

◆ mPptr

GpuIndexVectorX pbat::gpu::impl::vbd::Integrator::mPptr

|#partitions+1| partition pointers, s.t. the range [Pptr[p], /< Pptr[p+1]) indexes into Padj vertices from partition p

◆ mQuadratureWeights

common::Buffer<GpuScalar> pbat::gpu::impl::vbd::Integrator::mQuadratureWeights

|# elements| array of quadrature weights (i.e. tetrahedron volumes for order 1)

◆ mSmoothFrictionRelativeVelocityThreshold

GpuScalar pbat::gpu::impl::vbd::Integrator::mSmoothFrictionRelativeVelocityThreshold

IPC smooth friction transition function's relative velocity threshold

◆ mVertexTetrahedronLocalVertexIndices

common::Buffer<GpuIndex> pbat::gpu::impl::vbd::Integrator::mVertexTetrahedronLocalVertexIndices

Vertex-tetrahedron adjacency list's ilocal property

The documentation for this class was generated from the following files:

C:/git/PhysicsBasedAnimationToolkit/source/pbat/gpu/impl/vbd/Integrator.cuh
C:/git/PhysicsBasedAnimationToolkit/source/pbat/gpu/impl/vbd/Integrator.cu

Public Types

Public Member Functions

Public Attributes

Detailed Description

Member Typedef Documentation

◆ EInitializationStrategy

Constructor & Destructor Documentation

◆ Integrator()

Member Function Documentation

◆ BdfDeviceParameters()

◆ ComputeInertialTargets()

◆ InitializeActiveSet()

◆ InitializeBcdSolution()

◆ RunVbdIteration()

◆ SetBlockSize()

◆ SetSceneBoundingBox()

◆ Solve()

◆ Step()

◆ TracedSolve()

◆ TracedStep()

◆ UpdateBdfState()

Member Data Documentation

◆ fc

◆ mPptr

◆ mQuadratureWeights

◆ mSmoothFrictionRelativeVelocityThreshold

◆ mVertexTetrahedronLocalVertexIndices