vtkCompositeImplicitBackend< ValueType > Class Template Reference

A utility structure serving as a backend for composite arrays: an array composed of multiple arrays concatenated together. More...

#include <vtkCompositeImplicitBackend.h>

Public Member Functions
	vtkCompositeImplicitBackend (const std::vector< vtkDataArray * > &arrays)
	Constructor for the backend.
	vtkCompositeImplicitBackend (vtkDataArrayCollection *arrays)
	~vtkCompositeImplicitBackend ()
ValueType	operator() (vtkIdType idx) const
	Indexing operator for the composite of the two arrays respecting the vtkImplicitArray expectations.
unsigned long	getMemorySize () const
	Returns the smallest integer memory size in KiB needed to store the array.
vtkIdType	GetNumberOfArrays () const
	Get the number of original arrays composing this backend.
vtkDataArray *	GetArray (vtkIdType idx) const
	Get the original array at the given index.
vtkIdType	GetOffset (vtkIdType idx) const
	Get the tuple offset of the array at the given index.

Protected Attributes
std::unique_ptr< Internals >	Internal

Detailed Description

template<typename ValueType>
class vtkCompositeImplicitBackend< ValueType >

A utility structure serving as a backend for composite arrays: an array composed of multiple arrays concatenated together.

This structure can be classified as a closure and can be called using syntax similar to a function call.

This class uses indirect addressing of cached arrays to provide an access compute complexity of O(log_2(number_of_arrays)) through its () operator.

At construction it takes an array arrays in order to represent their concatenation.

An example of potential usage in a vtkImplicitArray

vtkNew<vtkIntArray> leftArr;
leftArr->SetNumberOfComponents(1);
leftArr->SetNumberOfTuples(1);
leftArr->SetValue(0, 0);
vtkNew<vtkIntArray> rightArr;
rightArr->SetNumberOfComponents(1);
rightArr->SetNumberOfTuples(1);
rightArr->SetValue(0, 1);
vtkNew<vtkImplicitArray<vtkCompositeImplicitBackend<int>>> compositeArr; // easier with
`vtkNew<vtkCompositeArray<int>> compositeArr;` if applicable
std::vector<vtkDataArray*> arrays({leftArr, rightArr});
compositeArr->SetBackend(std::make_shared<vtkCompositeImplicitBackend<int>>(arrays));
CHECK(compositArr->GetValue(1) == 1);

WARNING: Arrays input to the backend are flattened upon use and are no longer sensitive to component information.

Definition at line 52 of file vtkCompositeImplicitBackend.h.

Constructor & Destructor Documentation

vtkCompositeImplicitBackend() [1/2]

template<typename ValueType>

vtkCompositeImplicitBackend< ValueType >::vtkCompositeImplicitBackend

(

const std::vector< vtkDataArray * > &

arrays

)

Constructor for the backend.

Parameters

arrays

std::vector of arrays to composite together leftArr->GetNumberOfTuples()

vtkCompositeImplicitBackend() [2/2]

template<typename ValueType>

vtkCompositeImplicitBackend< ValueType >::vtkCompositeImplicitBackend

(

vtkDataArrayCollection *

arrays

)

~vtkCompositeImplicitBackend()

template<typename ValueType>

vtkCompositeImplicitBackend< ValueType >::~vtkCompositeImplicitBackend

(

)

Member Function Documentation

operator()()

template<typename ValueType>

ValueType vtkCompositeImplicitBackend< ValueType >::operator()

(

vtkIdType

idx

)

const

Indexing operator for the composite of the two arrays respecting the vtkImplicitArray expectations.

Conceptually, the composite array uses a binary search algorithm through the use of std::upper_bounds to offer a compute complexity of O(log_2(n_arrays))

getMemorySize()

template<typename ValueType>

unsigned long vtkCompositeImplicitBackend< ValueType >::getMemorySize

(

)

const

Returns the smallest integer memory size in KiB needed to store the array.

The memory size of the composite array is calculated as the sum of the sizes of its components. Used to implement GetActualMemorySize on vtkCompositeArray.

GetNumberOfArrays()

template<typename ValueType>

vtkIdType vtkCompositeImplicitBackend< ValueType >::GetNumberOfArrays

(

)

const

Get the number of original arrays composing this backend.

GetArray()

template<typename ValueType>

vtkDataArray * vtkCompositeImplicitBackend< ValueType >::GetArray

(

vtkIdType

idx

)

const

Get the original array at the given index.

GetOffset()

template<typename ValueType>

vtkIdType vtkCompositeImplicitBackend< ValueType >::GetOffset

(

vtkIdType

idx

)

const

Get the tuple offset of the array at the given index.

TupleOffset[i] = cumulative number of tuples in arrays 0..i-1.

Member Data Documentation

Internal

template<typename ValueType>

std::unique_ptr<Internals> vtkCompositeImplicitBackend< ValueType >::Internal

protected

Definition at line 98 of file vtkCompositeImplicitBackend.h.

---

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

• Common/Core/vtkCompositeImplicitBackend.h