cv::ogl::Buffer Class Reference

Smart pointer for OpenGL buffer object with reference counting. More...

#include <opencv2/core/opengl.hpp>

Public Types
enum	Access {   READ_ONLY = 0x88B8,   WRITE_ONLY = 0x88B9,   READ_WRITE = 0x88BA }
enum	Target {   ARRAY_BUFFER = 0x8892,   ELEMENT_ARRAY_BUFFER = 0x8893,   PIXEL_PACK_BUFFER = 0x88EB,   PIXEL_UNPACK_BUFFER = 0x88EC }
	The target defines how you intend to use the buffer object. More...

Public Member Functions
	Buffer ()
	The constructors. More...
	Buffer (int arows, int acols, int atype, unsigned int abufId, bool autoRelease=false)
	Buffer (Size asize, int atype, unsigned int abufId, bool autoRelease=false)
	Buffer (int arows, int acols, int atype, Target target=ARRAY_BUFFER, bool autoRelease=false)
	Buffer (Size asize, int atype, Target target=ARRAY_BUFFER, bool autoRelease=false)
	Buffer (InputArray arr, Target target=ARRAY_BUFFER, bool autoRelease=false)
void	bind (Target target) const
	Binds OpenGL buffer to the specified buffer binding point. More...
unsigned int	bufId () const
	get OpenGL opject id More...
int	channels () const
Buffer	clone (Target target=ARRAY_BUFFER, bool autoRelease=false) const
	Creates a full copy of the buffer object and the underlying data. More...
int	cols () const
void	copyFrom (InputArray arr, Target target=ARRAY_BUFFER, bool autoRelease=false)
	Copies from host/device memory to OpenGL buffer. More...
void	copyFrom (InputArray arr, cuda::Stream &stream, Target target=ARRAY_BUFFER, bool autoRelease=false)
void	copyTo (OutputArray arr) const
	Copies from OpenGL buffer to host/device memory or another OpenGL buffer object. More...
void	copyTo (OutputArray arr, cuda::Stream &stream) const
void	create (int arows, int acols, int atype, Target target=ARRAY_BUFFER, bool autoRelease=false)
	Allocates memory for ogl::Buffer object. More...
void	create (Size asize, int atype, Target target=ARRAY_BUFFER, bool autoRelease=false)
int	depth () const
int	elemSize () const
int	elemSize1 () const
bool	empty () const
cuda::GpuMat	mapDevice ()
	map to device memory (blocking) More...
cuda::GpuMat	mapDevice (cuda::Stream &stream)
	Maps OpenGL buffer to CUDA device memory. More...
Mat	mapHost (Access access)
	Maps OpenGL buffer to host memory. More...
void	release ()
	Decrements the reference counter and destroys the buffer object if needed. More...
int	rows () const
void	setAutoRelease (bool flag)
	Sets auto release mode. More...
Size	size () const
int	type () const
void	unmapDevice ()
void	unmapDevice (cuda::Stream &stream)
	Unmaps OpenGL buffer. More...
void	unmapHost ()
	Unmaps OpenGL buffer. More...

Static Public Member Functions
static void	unbind (Target target)
	Unbind any buffers from the specified binding point. More...

Detailed Description

Smart pointer for OpenGL buffer object with reference counting.

Buffer Objects are OpenGL objects that store an array of unformatted memory allocated by the OpenGL context. These can be used to store vertex data, pixel data retrieved from images or the framebuffer, and a variety of other things.

ogl::Buffer has interface similar with Mat interface and represents 2D array memory.

ogl::Buffer supports memory transfers between host and device and also can be mapped to CUDA memory.

Member Enumeration Documentation

Access

enum cv::ogl::Buffer::Access

Enumerator
READ_ONLY
WRITE_ONLY
READ_WRITE

Target

enum cv::ogl::Buffer::Target

The target defines how you intend to use the buffer object.

Enumerator
ARRAY_BUFFER	The buffer will be used as a source for vertex data.
ELEMENT_ARRAY_BUFFER	The buffer will be used for indices (in glDrawElements, for example)
PIXEL_PACK_BUFFER	The buffer will be used for reading from OpenGL textures.
PIXEL_UNPACK_BUFFER	The buffer will be used for writing to OpenGL textures.

Constructor & Destructor Documentation

Buffer() [1/6]

cv::ogl::Buffer::Buffer

(

)

The constructors.

Creates empty ogl::Buffer object, creates ogl::Buffer object from existed buffer ( abufId parameter), allocates memory for ogl::Buffer object or copies from host/device memory.

Buffer() [2/6]

cv::ogl::Buffer::Buffer	(	int	arows,
		int	acols,
		int	atype,
		unsigned int	abufId,
		bool	autoRelease = false
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

arows	Number of rows in a 2D array.
acols	Number of columns in a 2D array.
atype	Array type ( CV_8UC1, ..., CV_64FC4 ). See Mat for details.
abufId	Buffer object name.
autoRelease	Auto release mode (if true, release will be called in object's destructor).

Buffer() [3/6]

cv::ogl::Buffer::Buffer	(	Size	asize,
		int	atype,
		unsigned int	abufId,
		bool	autoRelease = false
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

asize	2D array size.
atype	Array type ( CV_8UC1, ..., CV_64FC4 ). See Mat for details.
abufId	Buffer object name.
autoRelease	Auto release mode (if true, release will be called in object's destructor).

Buffer() [4/6]

cv::ogl::Buffer::Buffer	(	int	arows,
		int	acols,
		int	atype,
		Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

arows	Number of rows in a 2D array.
acols	Number of columns in a 2D array.
atype	Array type ( CV_8UC1, ..., CV_64FC4 ). See Mat for details.
target	Buffer usage. See cv::ogl::Buffer::Target .
autoRelease	Auto release mode (if true, release will be called in object's destructor).

Buffer() [5/6]

cv::ogl::Buffer::Buffer	(	Size	asize,
		int	atype,
		Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

asize	2D array size.
atype	Array type ( CV_8UC1, ..., CV_64FC4 ). See Mat for details.
target	Buffer usage. See cv::ogl::Buffer::Target .
autoRelease	Auto release mode (if true, release will be called in object's destructor).

Buffer() [6/6]

cv::ogl::Buffer::Buffer ( InputArray  arr, Target  target = ARRAY_BUFFER, bool  autoRelease = false  )

explicit

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

arr	Input array (host or device memory, it can be Mat , cuda::GpuMat or std::vector ).
target	Buffer usage. See cv::ogl::Buffer::Target .
autoRelease	Auto release mode (if true, release will be called in object's destructor).

Member Function Documentation

bind()

void cv::ogl::Buffer::bind

(

Target

target

)

const

Binds OpenGL buffer to the specified buffer binding point.

Parameters

target

Binding point. See cv::ogl::Buffer::Target .

bufId()

unsigned int cv::ogl::Buffer::bufId

(

)

const

get OpenGL opject id

channels()

int cv::ogl::Buffer::channels

(

)

const

clone()

Buffer cv::ogl::Buffer::clone	(	Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)		const

Creates a full copy of the buffer object and the underlying data.

Parameters

target	Buffer usage for destination buffer.
autoRelease	Auto release mode for destination buffer.

cols()

int cv::ogl::Buffer::cols

(

)

const

copyFrom() [1/2]

void cv::ogl::Buffer::copyFrom	(	InputArray	arr,
		Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)

Copies from host/device memory to OpenGL buffer.

Parameters

arr	Input array (host or device memory, it can be Mat , cuda::GpuMat or std::vector ).
target	Buffer usage. See cv::ogl::Buffer::Target .
autoRelease	Auto release mode (if true, release will be called in object's destructor).

copyFrom() [2/2]

void cv::ogl::Buffer::copyFrom	(	InputArray	arr,
		cuda::Stream &	stream,
		Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

copyTo() [1/2]

void cv::ogl::Buffer::copyTo

(

OutputArray

arr

)

const

Copies from OpenGL buffer to host/device memory or another OpenGL buffer object.

Parameters

arr	Destination array (host or device memory, can be Mat , cuda::GpuMat , std::vector or ogl::Buffer ).

copyTo() [2/2]

void cv::ogl::Buffer::copyTo	(	OutputArray	arr,
		cuda::Stream &	stream
	)		const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

create() [1/2]

void cv::ogl::Buffer::create	(	int	arows,
		int	acols,
		int	atype,
		Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)

Allocates memory for ogl::Buffer object.

Parameters

arows	Number of rows in a 2D array.
acols	Number of columns in a 2D array.
atype	Array type ( CV_8UC1, ..., CV_64FC4 ). See Mat for details.
target	Buffer usage. See cv::ogl::Buffer::Target .
autoRelease	Auto release mode (if true, release will be called in object's destructor).

create() [2/2]

void cv::ogl::Buffer::create	(	Size	asize,
		int	atype,
		Target	target = ARRAY_BUFFER,
		bool	autoRelease = false
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

asize	2D array size.
atype	Array type ( CV_8UC1, ..., CV_64FC4 ). See Mat for details.
target	Buffer usage. See cv::ogl::Buffer::Target .
autoRelease	Auto release mode (if true, release will be called in object's destructor).

depth()

int cv::ogl::Buffer::depth

(

)

const

elemSize()

int cv::ogl::Buffer::elemSize

(

)

const

elemSize1()

int cv::ogl::Buffer::elemSize1

(

)

const

empty()

bool cv::ogl::Buffer::empty

(

)

const

mapDevice() [1/2]

cuda::GpuMat cv::ogl::Buffer::mapDevice

(

)

map to device memory (blocking)

mapDevice() [2/2]

cuda::GpuMat cv::ogl::Buffer::mapDevice

(

cuda::Stream &

stream

)

Maps OpenGL buffer to CUDA device memory.

This operation doesn't copy data. Several buffer objects can be mapped to CUDA memory at a time.

A mapped data store must be unmapped with ogl::Buffer::unmapDevice before its buffer object is used.

mapHost()

Mat cv::ogl::Buffer::mapHost

(

Access

access

)

Maps OpenGL buffer to host memory.

mapHost maps to the client's address space the entire data store of the buffer object. The data can then be directly read and/or written relative to the returned pointer, depending on the specified access policy.

A mapped data store must be unmapped with ogl::Buffer::unmapHost before its buffer object is used.

This operation can lead to memory transfers between host and device.

Only one buffer object can be mapped at a time.

Parameters

access

Access policy, indicating whether it will be possible to read from, write to, or both read from and write to the buffer object's mapped data store. The symbolic constant must be ogl::Buffer::READ_ONLY , ogl::Buffer::WRITE_ONLY or ogl::Buffer::READ_WRITE .

release()

void cv::ogl::Buffer::release

(

)

Decrements the reference counter and destroys the buffer object if needed.

The function will call setAutoRelease(true) .

rows()

int cv::ogl::Buffer::rows

(

)

const

setAutoRelease()

void cv::ogl::Buffer::setAutoRelease

(

bool

flag

)

Sets auto release mode.

The lifetime of the OpenGL object is tied to the lifetime of the context. If OpenGL context was bound to a window it could be released at any time (user can close a window). If object's destructor is called after destruction of the context it will cause an error. Thus ogl::Buffer doesn't destroy OpenGL object in destructor by default (all OpenGL resources will be released with OpenGL context). This function can force ogl::Buffer destructor to destroy OpenGL object.

Parameters

flag	Auto release mode (if true, release will be called in object's destructor).

size()

Size cv::ogl::Buffer::size

(

)

const

type()

int cv::ogl::Buffer::type

(

)

const

unbind()

static void cv::ogl::Buffer::unbind ( Target  target )

static

Unbind any buffers from the specified binding point.

Parameters

target

Binding point. See cv::ogl::Buffer::Target .

unmapDevice() [1/2]

void cv::ogl::Buffer::unmapDevice

(

)

unmapDevice() [2/2]

void cv::ogl::Buffer::unmapDevice

(

cuda::Stream &

stream

)

Unmaps OpenGL buffer.

unmapHost()

void cv::ogl::Buffer::unmapHost

(

)

Unmaps OpenGL buffer.

---

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

• opencv2/core/opengl.hpp