An array of cell status codes associates to each tetrahedron in a Delaunay tetrahedralization. More...

#include <geogram/delaunay/delaunay_sync.h>

Public Types
typedef uint8_t	thread_index_t

typedef uint8_t	cell_status_t

Public Member Functions
	CellStatusArray ()
	Creates an empty CellStatusArray.

	CellStatusArray (index_t size_in)
	Creates a CellStatusArray. More...

	~CellStatusArray ()
	CellStatusArray destructor. More...

	CellStatusArray (const CellStatusArray &rhs)=delete
	Forbids copy.

CellStatusArray &	operator= (const CellStatusArray &rhs)=delete
	Forbids copy.

cell_status_t	acquire_cell (index_t cell, cell_status_t status)
	Tentatively acquires a cell. More...

void	release_cell (index_t cell)
	Releases a cell. More...

cell_status_t	cell_thread (index_t cell) const
	Gets the thread that acquired a cell. More...

bool	cell_is_marked_as_conflict (index_t cell) const
	Tests whether a cell is marked as conflict. More...

void	mark_cell_as_conflict (index_t cell)
	Marks a cell as conflict. More...

void	set_cell_status (index_t cell, cell_status_t status)
	Sets the status of a cell. More...

void	resize (index_t size_in, index_t capacity_in)
	Resizes this CellStatusArray. More...

void	resize (index_t size_in)
	Resizes this CellStatusArray. More...

void	reserve (index_t new_capacity)
	Reserves additional space. More...

void	grow ()
	Increases the size of the array for one additional element. More...

index_t	size () const
	Gets the size of this CellStatusArray. More...

void	clear ()
	Clears this CellStatusArray. More...

Static Public Attributes
static constexpr cell_status_t	FREE_CELL = 127

static constexpr cell_status_t	THREAD_MASK = 127

static constexpr cell_status_t	CONFLICT_MASK = 128

static constexpr index_t	MAX_THREADS = index_t(THREAD_MASK)-1

Detailed Description

An array of cell status codes associates to each tetrahedron in a Delaunay tetrahedralization.

Each item can be atomically accessed to implement fine-grained resource control in a multithreaded context. It is used to memorize for each tetrahedron the thread that owns it as well as a couple of flags.

Definition at line 68 of file delaunay_sync.h.

Constructor & Destructor Documentation

◆ CellStatusArray()

GEO::CellStatusArray::CellStatusArray ( index_t size_in )

inline

Creates a CellStatusArray.

Parameters

[in] size_in number of cells in the CellStatusArray

Definition at line 97 of file delaunay_sync.h.

◆ ~CellStatusArray()

GEO::CellStatusArray::~CellStatusArray ( )

inline

CellStatusArray destructor.

It is illegal to destroy a CellStatusArray if

threads are still running
there exists a cell with a status different from FREE_CELL

Definition at line 108 of file delaunay_sync.h.

Member Function Documentation

◆ acquire_cell()

cell_status_t GEO::CellStatusArray::acquire_cell	(	index_t	cell,
		cell_status_t	status
	)

inline

Tentatively acquires a cell.

Parameters

[in]	cell	the index of the cell
[in]	status	the status to be written in the cell if acquisition is successful, that is, if the current status of the cell is FREE_CELL

Returns: FREE_CELL if acquisition was successful, or the id of the thread that owns cell otherwise.

Definition at line 131 of file delaunay_sync.h.

◆ cell_is_marked_as_conflict()

bool GEO::CellStatusArray::cell_is_marked_as_conflict ( index_t cell ) const

inline

Tests whether a cell is marked as conflict.

Parameters

[in] cell the cell

Return values

true	if `cell` is marked as conflict
false	otherwise

See also: mark_cell_as_conflict()

Definition at line 176 of file delaunay_sync.h.

◆ cell_thread()

cell_status_t GEO::CellStatusArray::cell_thread ( index_t cell ) const

inline

Gets the thread that acquired a cell.

Parameters

[in] cell the cell

Returns: the index of the thread that acquired the cell, or FREE_CELL if the cell is free

Definition at line 161 of file delaunay_sync.h.

◆ clear()

void GEO::CellStatusArray::clear ( )

inline

Clears this CellStatusArray.

Deallocates all memory

Precondition: all the cells are free and no concurrent thread is running

Definition at line 287 of file delaunay_sync.h.

◆ grow()

void GEO::CellStatusArray::grow ( )

inline

Increases the size of the array for one additional element.

capacity is doubled each time additional space is needed

Definition at line 266 of file delaunay_sync.h.

◆ mark_cell_as_conflict()

void GEO::CellStatusArray::mark_cell_as_conflict ( index_t cell )

inline

Marks a cell as conflict.

Parameters

[in] cell the cell

Precondition: the cell is owned by the current thread

Definition at line 191 of file delaunay_sync.h.

◆ release_cell()

void GEO::CellStatusArray::release_cell ( index_t cell )

inline

Releases a cell.

Parameters

[in] cell the index of the cell

Precondition: the cell is owned by the current thread

Definition at line 150 of file delaunay_sync.h.

◆ reserve()

void GEO::CellStatusArray::reserve ( index_t new_capacity )

inline

Reserves additional space.

Parameters

[in] new_capacity on exit, this CellStatusArray will have at least sufficient space for new_capacity elements without needing to reallocate. Size is not modified. Operates like its std::vector counterpart.

Definition at line 256 of file delaunay_sync.h.

◆ resize() [1/2]

void GEO::CellStatusArray::resize ( index_t size_in )

inline

Resizes this CellStatusArray.

Parameters

[in] size_in number of cells

Precondition: all cells are free and no concurrent thread is currently running

Definition at line 245 of file delaunay_sync.h.

◆ resize() [2/2]

void GEO::CellStatusArray::resize	(	index_t	size_in,
		index_t	capacity_in
	)

inline

Resizes this CellStatusArray.

Parameters

[in]	size_in	number of cells
[in]	capacity_in	total number of allocated cells

Precondition: capacity_in >= size_in and no concurrent thread is currently running

Definition at line 217 of file delaunay_sync.h.

◆ set_cell_status()

void GEO::CellStatusArray::set_cell_status	(	index_t	cell,
		cell_status_t	status
	)

inline

Sets the status of a cell.

Parameters

[in] cell the index of the cell

uses relaxed memory ordering

Precondition: the cell is owned by the current thread

Definition at line 205 of file delaunay_sync.h.

◆ size()

index_t GEO::CellStatusArray::size ( ) const

inline

Gets the size of this CellStatusArray.

Returns: the number of cells

Definition at line 278 of file delaunay_sync.h.

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

geogram/delaunay/delaunay_sync.h

Public Types

Public Member Functions

Static Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ CellStatusArray()

◆ ~CellStatusArray()

Member Function Documentation

◆ acquire_cell()

◆ cell_is_marked_as_conflict()

◆ cell_thread()

◆ clear()

◆ grow()

◆ mark_cell_as_conflict()

◆ release_cell()

◆ reserve()

◆ resize() [1/2]

◆ resize() [2/2]

◆ set_cell_status()

◆ size()