viskores::cont::CellLocatorTwoLevel Class Reference

A locator that uses 2 nested levels of grids. More...

#include <CellLocatorTwoLevel.h>

Inheritance diagram for viskores::cont::CellLocatorTwoLevel:

Public Types
using	SupportedCellSets = ::viskores::cont::internal::CellSetList
using	CellExecObjectList = viskores::ListTransform< SupportedCellSets, CellSetContToExec >
using	CellLocatorExecList = viskores::ListTransform< CellExecObjectList, viskores::exec::CellLocatorTwoLevel >
using	ExecObjType = viskores::ListApply< CellLocatorExecList, viskores::exec::CellLocatorMultiplexer >
using	LastCell = typename ExecObjType::LastCell

Public Member Functions
	CellLocatorTwoLevel ()
void	SetDensityL1 (viskores::FloatDefault val)
	Specify the desired approximate number of cells per level 1 bin. More...
viskores::FloatDefault	GetDensityL1 () const
	Specify the desired approximate number of cells per level 1 bin. More...
void	SetDensityL2 (viskores::FloatDefault val)
	Specify the desired approximate number of cells per level 2 bin. More...
viskores::FloatDefault	GetDensityL2 () const
	Specify the desired approximate number of cells per level 2 bin. More...
void	PrintSummary (std::ostream &out) const
	Print a summary of the state of this locator. More...
ExecObjType	PrepareForExecution (viskores::cont::DeviceAdapterId device, viskores::cont::Token &token) const
Public Member Functions inherited from viskores::cont::CellLocatorBase
virtual	~CellLocatorBase ()=default
const viskores::cont::UnknownCellSet &	GetCellSet () const
	Specify the CellSet defining the structure of the cells being searched. More...
void	SetCellSet (const viskores::cont::UnknownCellSet &cellSet)
	Specify the CellSet defining the structure of the cells being searched. More...
const viskores::cont::CoordinateSystem &	GetCoordinates () const
	Specify the CoordinateSystem defining the location of the cells. More...
void	SetCoordinates (const viskores::cont::CoordinateSystem &coords)
	Specify the CoordinateSystem defining the location of the cells. More...
void	SetCoordinates (const viskores::cont::UnknownArrayHandle &coords)
	Specify the CoordinateSystem defining the location of the cells. More...
void	Update () const
	Build the search structure used to look up cells. More...

Private Types
template<typename CellSetCont >
using	CellSetContToExec = typename CellSetCont::template ExecConnectivityType< viskores::TopologyElementTagCell, viskores::TopologyElementTagPoint >

Private Member Functions
void	Build () override

Private Attributes
viskores::FloatDefault	DensityL1
viskores::FloatDefault	DensityL2
viskores::internal::cl_uniform_bins::Grid	TopLevel
viskores::cont::ArrayHandle< viskores::internal::cl_uniform_bins::DimVec3 >	LeafDimensions
viskores::cont::ArrayHandle< viskores::Id >	LeafStartIndex
viskores::cont::ArrayHandle< viskores::Id >	CellStartIndex
viskores::cont::ArrayHandle< viskores::Id >	CellCount
viskores::cont::ArrayHandle< viskores::Id >	CellIds

Additional Inherited Members
Protected Member Functions inherited from viskores::cont::CellLocatorBase
void	SetModified ()
bool	GetModified () const

Detailed Description

A locator that uses 2 nested levels of grids.

CellLocatorTwoLevel creates a cell search structure using two levels of structured grids. The first level is a coarse grid that covers the entire region of the data. It is expected that the distributions of dataset cells in this coarse grid will be very uneven. Within each bin of the coarse grid, a second level grid is defined within the spatial bounds of the coarse bin. The size of this second level grid is proportional to the number of cells in the first level. In this way, the second level grids adapt to the distribution of cells being located. The adaption is not perfect, but it is has very good space efficiency and is fast to generate and use.

The algorithm used in CellLocatorTwoLevel is described in the following publication:

Javor Kalojanov, Markus Billeter, and Philipp Slusallek. "Two-Level Grids for Ray Tracing on GPUs." Computer Graphics Forum, 2011, pages 307-314. DOI 10.1111/j.1467-8659.2011.01862.x

Member Typedef Documentation

CellExecObjectList

using viskores::cont::CellLocatorTwoLevel::CellExecObjectList = viskores::ListTransform<SupportedCellSets, CellSetContToExec>

CellLocatorExecList

using viskores::cont::CellLocatorTwoLevel::CellLocatorExecList = viskores::ListTransform<CellExecObjectList, viskores::exec::CellLocatorTwoLevel>

CellSetContToExec

template<typename CellSetCont >

using viskores::cont::CellLocatorTwoLevel::CellSetContToExec = typename CellSetCont::template ExecConnectivityType<viskores::TopologyElementTagCell, viskores::TopologyElementTagPoint>

private

ExecObjType

using viskores::cont::CellLocatorTwoLevel::ExecObjType = viskores::ListApply<CellLocatorExecList, viskores::exec::CellLocatorMultiplexer>

LastCell

using viskores::cont::CellLocatorTwoLevel::LastCell = typename ExecObjType::LastCell

SupportedCellSets

using viskores::cont::CellLocatorTwoLevel::SupportedCellSets = ::viskores::cont::internal::CellSetList

Constructor & Destructor Documentation

CellLocatorTwoLevel()

viskores::cont::CellLocatorTwoLevel::CellLocatorTwoLevel ( )

inline

Member Function Documentation

Build()

void viskores::cont::CellLocatorTwoLevel::Build ( )

overrideprivatevirtual

Implements viskores::cont::CellLocatorBase.

GetDensityL1()

viskores::FloatDefault viskores::cont::CellLocatorTwoLevel::GetDensityL1 ( ) const

inline

Specify the desired approximate number of cells per level 1 bin.

The default value is 32.

GetDensityL2()

viskores::FloatDefault viskores::cont::CellLocatorTwoLevel::GetDensityL2 ( ) const

inline

Specify the desired approximate number of cells per level 2 bin.

This value should be relatively small as it is close to the average number of cells that must be checked for each find. The default value is 2.

PrepareForExecution()

ExecObjType viskores::cont::CellLocatorTwoLevel::PrepareForExecution	(	viskores::cont::DeviceAdapterId	device,
		viskores::cont::Token &	token
	)		const

PrintSummary()

void viskores::cont::CellLocatorTwoLevel::PrintSummary

(

std::ostream &

out

)

const

Print a summary of the state of this locator.

SetDensityL1()

void viskores::cont::CellLocatorTwoLevel::SetDensityL1 ( viskores::FloatDefault  val )

inline

Specify the desired approximate number of cells per level 1 bin.

The default value is 32.

SetDensityL2()

void viskores::cont::CellLocatorTwoLevel::SetDensityL2 ( viskores::FloatDefault  val )

inline

Specify the desired approximate number of cells per level 2 bin.

This value should be relatively small as it is close to the average number of cells that must be checked for each find. The default value is 2.

Member Data Documentation

CellCount

viskores::cont::ArrayHandle<viskores::Id> viskores::cont::CellLocatorTwoLevel::CellCount

private

CellIds

viskores::cont::ArrayHandle<viskores::Id> viskores::cont::CellLocatorTwoLevel::CellIds

private

CellStartIndex

viskores::cont::ArrayHandle<viskores::Id> viskores::cont::CellLocatorTwoLevel::CellStartIndex

private

DensityL1

viskores::FloatDefault viskores::cont::CellLocatorTwoLevel::DensityL1

private

DensityL2

viskores::FloatDefault viskores::cont::CellLocatorTwoLevel::DensityL2

private

LeafDimensions

viskores::cont::ArrayHandle<viskores::internal::cl_uniform_bins::DimVec3> viskores::cont::CellLocatorTwoLevel::LeafDimensions

private

LeafStartIndex

viskores::cont::ArrayHandle<viskores::Id> viskores::cont::CellLocatorTwoLevel::LeafStartIndex

private

TopLevel

viskores::internal::cl_uniform_bins::Grid viskores::cont::CellLocatorTwoLevel::TopLevel

private

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

• cont/CellLocatorTwoLevel.h