OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type > Class Template Reference

#include <spatial_hashing_grid.h>

List of all members.

Classes
class	Cell
Public Types
typedef data_type_	data_type
typedef real_vector3::value_type	real_type
typedef int_vector3	triplet_type
	Type of discretized points.
typedef real_vector3	point_type
	Type of continuous points.
typedef Cell	cell_type
typedef std::vector< cell_type >	cell_storage
typedef cell_storage::iterator	cell_iterator
Public Member Functions
cell_iterator	begin ()
cell_iterator	end ()
	Grid ()
	Grid (size_t size)
void	resize (size_t size)
size_t	size () const
void	set_spacing (real_type delta)
real_type	get_spacing () const
triplet_type	get_triplet (point_type const &point) const
cell_type &	get_cell (point_type const &p)
cell_type &	get_cell (triplet_type const &triplet)
void	clear ()
Protected Types
typedef std::vector< data_type * >	data_ptr_container
typedef data_ptr_container::iterator	data_ptr_iterator
typedef data_ptr_container::const_iterator	const_data_ptr_iterator
Protected Attributes
size_t	m_time_stamp
	Query time-stamp.
real_type	m_delta
	Grid cell spacing.
hash_function_type	m_hash_function
cell_storage	m_cells
	Hash table cells.

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Detailed Description

template<typename real_vector3, typename int_vector3, typename data_type_, typename hash_function_type>
class OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >

Hash Grid. This class stores an infinite uniform 3D grid as a 1D hash tabel. It is tailored to work in 3D. However, an end user could use it in 2D or even 1D by ignoring second or third coordinates (i.e. set them all to the same value).

The hash grid needs a hash function, a hash function must surply the following interface

size_t operator(int ,int , int)const size_t size()const void resize(size_t)

Important: The hash function is responsible for picking the proper hash table size. Thus if resize is invoked and the implemented hash function for instance implements something like:

m_size = new_size + (new_size % 10)

In which case the hash grid will automatically make sure that m_size is used to allocate the number of hash cells. The size() method is expected to return the value of m_size.

The operator(int,int,int) should convert a discretized point into a 1D hash key. The hash key value is expected to be within the interval 0..m_size-1.

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Member Typedef Documentation

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef cell_storage::iterator OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::cell_iterator

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef std::vector< cell_type > OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::cell_storage

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef Cell OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::cell_type

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef data_ptr_container::const_iterator OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::const_data_ptr_iterator [protected]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef std::vector<data_type*> OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::data_ptr_container [protected]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef data_ptr_container::iterator OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::data_ptr_iterator [protected]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef data_type_ OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::data_type

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef real_vector3 OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::point_type

Type of continuous points.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef real_vector3::value_type OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::real_type

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

typedef int_vector3 OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::triplet_type

Type of discretized points.

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Constructor & Destructor Documentation

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::Grid

(

)

[inline]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::Grid

(

size_t

size

)

[inline]

---

Member Function Documentation

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

cell_iterator OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::begin

(

)

[inline]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

void OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::clear

(

)

[inline]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

cell_iterator OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::end

(

)

[inline]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

cell_type& OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::get_cell

(

triplet_type const &

triplet

)

[inline]

Find the hash cell containing the grid cell enclosing the discretized point.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

cell_type& OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::get_cell

(

point_type const &

p

)

[inline]

Find the hash cell containing the grid cell enclosing the continuous point.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

real_type OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::get_spacing

(

)

const [inline]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

triplet_type OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::get_triplet

(

point_type const &

point

)

const [inline]

Point Discretization.

Parameters:

p

A 3D point in continious space

Returns:

A discretized point identifying the grid cell (not the hash cell!) which the contineous point lies inside.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

void OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::resize

(

size_t

size

)

[inline]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

void OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::set_spacing

(

real_type

delta

)

[inline]

Set Grid Cell Spacing. Observe that a grid cell is not the same as a hash-cell, data inside a grid cell is mapped to a hash-cell, this is not a one-to-one mapping. In fact multiple grid cells can be mapped to the same hash-cell (this is called a hash-collision).

To reduce the chance of this, try increase the hash-table size, this will decrease the chance of hash-collisions.

For point type data, the grid spacing should usually be set to the average size of the query data used.

For volumetric data, the grid spacing should usually be set to the average size of the volumetric data.

Parameters:

delta

The new grid cell spacing size, must be a positive number.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

size_t OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::size

(

)

const [inline]

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Member Data Documentation

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

cell_storage OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::m_cells [protected]

Hash table cells.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

real_type OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::m_delta [protected]

Grid cell spacing.

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

hash_function_type OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::m_hash_function [protected]

template<typename real_vector3 , typename int_vector3 , typename data_type_ , typename hash_function_type >

size_t OpenTissue::spatial_hashing::Grid< real_vector3, int_vector3, data_type_, hash_function_type >::m_time_stamp [protected]

Query time-stamp.

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

• /home/hauberg/Dokumenter/Capture/humim-tracker-0.1/src/OpenTissue/OpenTissue/collision/spatial_hashing/spatial_hashing_grid.h