gpu::Buffer Class Reference

#include <Buffer.h>

Inheritance diagram for gpu::Buffer:

Collaboration diagram for gpu::Buffer:

Classes
class	Update

Public Member Functions
	Buffer (uint32_t usage, Size pageSize=PageManager::DEFAULT_PAGE_SIZE)
	Buffer (uint32_t usage, Size size, const Byte *bytes, Size pageSize=PageManager::DEFAULT_PAGE_SIZE)
	Creates buffer with a given content. More...
	Buffer (const Buffer &buf)
	Copy constructor. More...
Buffer &	operator= (const Buffer &buf)
	Assignment constructor. More...
	~Buffer ()
Size	getSize () const override
template<typename T >
Size	getNumTypedElements () const
const Byte *	getData () const
uint32_t	getUsage () const
Size	resize (Size pSize)
	Resizes buffer. More...
Size	setData (Size size, const Byte *data)
	Assign data bytes and size (allocate for size, then copy bytes if exists). More...
Size	setSubData (Size offset, Size size, const Byte *data)
	Set a subset of buffer's data. More...
template<typename T >
Size	setSubData (Size index, const T &t)
	Set a subset of buffer's data using data of a given object. More...
template<typename T >
Size	setSubData (Size index, const std::vector< T > &t)
	Set a subset of buffer's data using a vector of objects of a given type. More...
Size	append (Size size, const Byte *data)
	Append new data at the end of the current buffer. More...
template<typename T >
Size	append (const T &t)
	Append new data at the end of the current buffer from an object of a given type. More...
template<typename T >
Size	append (const std::vector< T > &t)
	Append new data at the end of the current buffer using a vector of objects of a given type. More...
const Sysmem &	getSysmem () const
	Access the sysmem object. More...
bool	isDirty () const
void	applyUpdate (const Update &update)
	Applies update to a buffer. More...
Update	getUpdate () const
	Generate Update object from the current changes to the buffer. More...

Static Public Member Functions
static uint32_t	getBufferCPUCount ()
static Size	getBufferCPUMemSize ()
template<typename T >
static Buffer *	createBuffer (uint32_t usage, const std::vector< T > &v)
	Creates a buffer from std::vector. More...

Public Attributes
const GPUObjectPointer	gpuObject {}

Protected Member Functions
void	incrementCreatedBufferCount ()
	Counter used for debugging excessive creation of buffers.
void	flush () const
	Instantly applies current changes to a buffer without creating an Update object. More...
void	markDirty (Size offset, Size bytes)
	Marks pages on which specified data range is stored as dirty. More...
template<typename T >
void	markDirty (Size index, Size count=1)
	Marks pages on which data from a number of objects of a specified type range is stored as dirty. More...
Sysmem &	editSysmem ()
Byte *	editData ()
	Returns pointer to data to be edited, but data still needs to be flagged as dirty with a separate makeDirty call. More...

Protected Attributes
PageManager	_renderPages
Sysmem	_renderSysmem
std::atomic< size_t >	_getUpdateCount { 0 }
std::atomic< size_t >	_applyUpdateCount { 0 }
PageManager	_pages
Size	_end { 0 }
Sysmem	_sysmem
const uint32_t	_usage { 0 }

Detailed Description

Represents various kinds of buffers (index, vertex, uniform, resource, etc.) on the CPU side.

Constructor & Destructor Documentation

Buffer() [1/3]

Buffer::Buffer	(	uint32_t	usage,
		Size	pageSize = PageManager::DEFAULT_PAGE_SIZE
	)

Parameters

usage	A bit sum of Buffer::Usage flags describing this buffer.
pageSize	Size of the page in bytes. Pages are the smallest parts of the buffer that can be updated.

Buffer() [2/3]

Buffer::Buffer	(	uint32_t	usage,
		Size	size,
		const Byte *	bytes,
		Size	pageSize = PageManager::DEFAULT_PAGE_SIZE
	)

Creates buffer with a given content.

Parameters

usage	Planned usage of this buffer, bit sum of Buffer::Usage flags.
size	Size in bytes.
bytes	Pointer to the data.
pageSize	Size of the page in bytes. Pages are the smallest parts of the buffer that can be updated.

Buffer() [3/3]

Buffer::Buffer

(

const Buffer &

buf

)

Copy constructor.

Performs deep copy of the sysmem buffer.

Parameters

buf	Buffer to be copied.

~Buffer()

Buffer::~Buffer

(

)

Buffer destructor updated statistics.

Member Function Documentation

append() [1/3]

template<typename T >

Size gpu::Buffer::append ( const std::vector< T > &  t )

inline

Append new data at the end of the current buffer using a vector of objects of a given type.

Template Parameters

T	Object type.

Parameters

t	Vector of objects that will be the source of data.

Returns

Number of bytes copied.

append() [2/3]

template<typename T >

Size gpu::Buffer::append ( const T &  t )

inline

Append new data at the end of the current buffer from an object of a given type.

Template Parameters

T	Object type.

Parameters

t	Instance of the object that will be the source of data.

Returns

Number of bytes copied.

append() [3/3]

Buffer::Size Buffer::append	(	Size	size,
		const Byte *	data
	)

Append new data at the end of the current buffer.

Resizes buffer to (size + getSize) and copies the new data.

Parameters

size	Size of the data to append in bytes.
data	Pointer to the data.

Returns

Number of bytes copied.

applyUpdate()

void Buffer::applyUpdate

(

const Update &

update

)

Applies update to a buffer.

After the batches are generated changes to the buffer contents need to be applied. The reason for this is that a frame is executed at the same time as another frame object is being generated.

Parameters

update

Update object to apply.

createBuffer()

template<typename T >

static Buffer* gpu::Buffer::createBuffer ( uint32_t  usage, const std::vector< T > &  v  )

inlinestatic

Creates a buffer from std::vector.

Template Parameters

T	Vector type.

Parameters

usage	Planned usage of this buffer, bit sum of Buffer::Usage flags.
v	Vector, which contents will be copied to the buffer.

Returns

Pointer to the newly created buffer.

editData()

Byte* gpu::Buffer::editData ( )

inlineprotected

Returns pointer to data to be edited, but data still needs to be flagged as dirty with a separate makeDirty call.

Returns

Pointer to buffer data.

editSysmem()

Sysmem& gpu::Buffer::editSysmem ( )

inlineprotected

Returns

Reference to sysmem object.

flush()

void Buffer::flush ( ) const

protected

Instantly applies current changes to a buffer without creating an Update object.

For use by the render thread to avoid the intermediate step of getUpdate/applyUpdate.

getBufferCPUCount()

uint32_t Buffer::getBufferCPUCount ( )

static

Returns

Total count of currently existing buffers.

getBufferCPUMemSize()

Buffer::Size Buffer::getBufferCPUMemSize ( )

static

Returns

Total size in bytes of currently existing buffers.

getData()

const Byte* gpu::Buffer::getData ( ) const

inline

Returns

Constant pointer to buffer data.

getNumTypedElements()

template<typename T >

Size gpu::Buffer::getNumTypedElements ( ) const

inline

Template Parameters

T	Element type.

Returns

Number of elements of a given type in the buffer.

getSize()

Buffer::Size Buffer::getSize ( ) const

overridevirtual

Returns

The size in bytes of data stored in the buffer

Implements gpu::Resource.

getSysmem()

const Sysmem& gpu::Buffer::getSysmem ( ) const

inline

Access the sysmem object.

Symsmem object contains buffer data on the CPU side. Rendering backends upload it to the GPU. Intended only for Buffer and GPUObject derived classes.

Returns

Constant reference to the sysmem object.

getUpdate()

Buffer::Update Buffer::getUpdate

(

)

const

Generate Update object from the current changes to the buffer.

Should be called only if isDirty returns true.

Returns

Update object.

getUsage()

uint32_t gpu::Buffer::getUsage ( ) const

inline

Returns

Returns usage, which is a bit sum of Buffer::Usage flags.

isDirty()

bool gpu::Buffer::isDirty ( ) const

inline

Returns

true if there are updates for this buffer that were not applied yet.

markDirty() [1/2]

template<typename T >

void gpu::Buffer::markDirty ( Size  index, Size  count = 1  )

inlineprotected

Marks pages on which data from a number of objects of a specified type range is stored as dirty.

Template Parameters

T	Type of the object from which data is stored.

Parameters

index	Start position. Offset in bytes is index * sizeof(T).
count	Number of objects to mark as dirty. Range in bytes is count * sizeof(T).

markDirty() [2/2]

void Buffer::markDirty ( Size  offset, Size  bytes  )

protected

Marks pages on which specified data range is stored as dirty.

Used to notify buffer update system that data was edited.

Parameters

offset
bytes

operator=()

Buffer & Buffer::operator=

(

const Buffer &

buf

)

Assignment constructor.

Performs deep copy of the sysmem buffer.

Parameters

buf	Buffer to be copied.

Returns

Reference to the destination buffer.

resize()

Buffer::Size Buffer::resize

(

Size

pSize

)

Resizes buffer.

Keeps previous data [0 to min(pSize, mSize)].

Parameters

pSize

New size in bytes.

Returns

New size, same as input parameter.

setData()

Buffer::Size Buffer::setData	(	Size	size,
		const Byte *	data
	)

Assign data bytes and size (allocate for size, then copy bytes if exists).

Parameters

size	New size in bytes.
data	Pointer to data of size specified in the previous parameter.

Returns

New size, same as input parameter.

setSubData() [1/3]

template<typename T >

Size gpu::Buffer::setSubData ( Size  index, const std::vector< T > &  t  )

inline

Set a subset of buffer's data using a vector of objects of a given type.

Template Parameters

T	Object type.

Parameters

index	Position in the buffer to which to write to. Offset in bytes is (index * sizeof(T)).
t	Vector of objects that will be the source of data.

Returns

Number of bytes written.

setSubData() [2/3]

template<typename T >

Size gpu::Buffer::setSubData ( Size  index, const T &  t  )

inline

Set a subset of buffer's data using data of a given object.

Template Parameters

T	Type of the object.

Parameters

index	Position in the buffer to which to write to. Offset in bytes is (index * sizeof(T)).
t	Instance of the object that will be the source of data.

Returns

Number of bytes written.

setSubData() [3/3]

Buffer::Size Buffer::setSubData	(	Size	offset,
		Size	size,
		const Byte *	data
	)

Set a subset of buffer's data.

Fails and returns 0 if buffer is not big enough.

Parameters

offset	Offset at which to start writing data.
size	Size in bytes of data to write.
data	Pointer to the data.

Returns

The number of bytes copied or zero if it was not possible to copy them.

Member Data Documentation

_applyUpdateCount

std::atomic<size_t> gpu::Buffer::_applyUpdateCount { 0 }

mutableprotected

Number of times a buffer update object was applied.

_end

Size gpu::Buffer::_end { 0 }

protected

Size of the buffer.

_getUpdateCount

std::atomic<size_t> gpu::Buffer::_getUpdateCount { 0 }

mutableprotected

Number of times a buffer update object was created.

_pages

PageManager gpu::Buffer::_pages

mutableprotected

PageManager for _sysmem. When buffer memory is edited, pages that were changed are flagged here and then Update object can be generated. Later applying the update copies changes to _renderSysmem object.

_renderPages

PageManager gpu::Buffer::_renderPages

mutableprotected

PageManager for second copy of the buffer (one ot which updates are applied).

_renderSysmem

Sysmem gpu::Buffer::_renderSysmem

mutableprotected

Second copy of the buffer. Update objects need to be generated from _sysmem and applying them copies them to _renderSysmem.

_sysmem

Sysmem gpu::Buffer::_sysmem

protected

Changes to the buffer are written here, and then pages corresponding to them in _pages are marked as dirty. This is later used to create Update object that can be applied to _renderSysmem.

_usage

const uint32_t gpu::Buffer::_usage { 0 }

protected

Usage of this buffer. It's a bit sum of Buffer::Usage.

gpuObject

const GPUObjectPointer gpu::Buffer::gpuObject {}

Pointer to the renderer backend object associated with this object. The renderer backend object will have different type depending on currently running backend, for example OpenGL or Vulkan.

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

• Buffer.h
• Buffer.cpp