ImFusion::Container::SmallVector< T, N > Class Template Reference

#include <ImFusion/Core/SmallVector.h>

A small-buffer-optimized variant of std::vector that stores up to N elements without heap allocation. More...

Detailed Description

template<typename T, std::size_t N = 8>
class ImFusion::Container::SmallVector< T, N >

A small-buffer-optimized variant of std::vector that stores up to N elements without heap allocation.

When the number of elements grows beyond N a heap allocation is used so that SmallVector behaves like a regular std::vector. Use this container when the number of elements is usually small and short-lived, but can occasionally grow dynamically. Typical examples are temporary working sets, per-frame buffers, or collections built in tight loops where avoiding frequent heap allocations improves performance.

Prefer SmallVector over std::vector if:

• Most instances contain only a few elements (often <= N), and
• You want to reduce allocator traffic and improve locality.

Prefer std::vector if:

• Sizes are typically large or highly variable, or
• You need full STL API compatibility beyond the subset provided here.

Example:

// The majority of use cases have a maximum of 4 channels, in this case no heap allocation is performed.
Container::SmallVector<double, 4> channelData;
for (int c = 0; c < img.channels(); ++c)
    channelData.push_back(img.value(x, y, z, c));
 
processChannels(channelData);

Template Parameters

T	Element type
N	Maximum number of elements stored inline without heap allocation

Public Types
using	value_type = T
using	size_type = std::size_t
using	iterator = T*
using	const_iterator = const T*

Public Member Functions
	SmallVector (const SmallVector &other)
	SmallVector (SmallVector &&other) noexcept(std::is_nothrow_move_constructible< T >::value)
SmallVector &	operator= (const SmallVector &other)
SmallVector &	operator= (SmallVector &&other) noexcept(std::is_nothrow_move_constructible< T >::value)
T &	operator[] (size_type i)
const T &	operator[] (size_type i) const
T *	data () noexcept
const T *	data () const noexcept
T &	front ()
const T &	front () const
T &	back ()
const T &	back () const
size_type	size () const noexcept
size_type	capacity () const noexcept
bool	isEmpty () const noexcept
void	push_back (const T &value)
void	push_back (T &&value)
template<typename... Args>
T &	emplace_back (Args &&... args)
iterator	insert (const_iterator pos, const T &value)
iterator	insert (const_iterator pos, T &&value)
void	pop_back ()
iterator	erase (const_iterator pos)
void	clear () noexcept
void	reserve (size_type newCap)
void	resize (size_type newSize)
void	shrink_to_fit ()
iterator	begin () noexcept
iterator	end () noexcept
const_iterator	begin () const noexcept
const_iterator	end () const noexcept
const_iterator	cbegin () const noexcept
const_iterator	cend () const noexcept

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

• ImFusion/Core/SmallVector.h