OpenGLFrameBuffer Class Reference

Creates an openGL frame buffer. More...

#include <juce_OpenGLFrameBuffer.h>

Public Member Functions
	OpenGLFrameBuffer ()
	Creates an uninitialised buffer.
	~OpenGLFrameBuffer ()
	Destructor.
bool	initialise (OpenGLContext &context, int width, int height)
	Tries to allocates a buffer of the given size.
bool	initialise (OpenGLContext &context, const Image &content)
	Tries to allocates a buffer containing a copy of a given image.
bool	initialise (OpenGLFrameBuffer &other)
	Tries to allocate a copy of another framebuffer.
void	release ()
	Releases the buffer, if one has been allocated.
void	saveAndRelease ()
	If the framebuffer is active, this will save a stashed copy of its contents in main memory, and will release the GL buffer.
bool	reloadSavedCopy (OpenGLContext &context)
	Restores the framebuffer content that was previously saved using saveAndRelease().
bool	isValid () const noexcept
	Returns true if a valid buffer has been allocated.
int	getWidth () const noexcept
	Returns the width of the buffer.
int	getHeight () const noexcept
	Returns the height of the buffer.
GLuint	getTextureID () const noexcept
	Returns the texture ID number for using this buffer as a texture.
bool	makeCurrentRenderingTarget ()
	Selects this buffer as the current OpenGL rendering target.
void	releaseAsRenderingTarget ()
	Deselects this buffer as the current OpenGL rendering target.
GLuint	getFrameBufferID () const noexcept
	Returns the ID of this framebuffer, or 0 if it isn't initialised.
void	clear (Colour colour)
	Clears the framebuffer with the specified colour.
void	makeCurrentAndClear ()
	Selects the framebuffer as the current target, and clears it to transparent.
bool	readPixels (PixelARGB *targetData, const Rectangle< int > &sourceArea)
	Reads an area of pixels from the framebuffer into a 32-bit ARGB pixel array.
bool	writePixels (const PixelARGB *srcData, const Rectangle< int > &targetArea)
	Writes an area of pixels into the framebuffer from a specified pixel array.

Static Public Member Functions
static GLuint	getCurrentFrameBufferTarget () noexcept
	Returns the current frame buffer ID for the current context.

Detailed Description

Creates an openGL frame buffer.

Constructor & Destructor Documentation

OpenGLFrameBuffer()

OpenGLFrameBuffer::OpenGLFrameBuffer

(

)

Creates an uninitialised buffer.

To actually allocate the buffer, use initialise().

~OpenGLFrameBuffer()

OpenGLFrameBuffer::~OpenGLFrameBuffer

(

)

Destructor.

Member Function Documentation

initialise() [1/3]

bool OpenGLFrameBuffer::initialise	(	OpenGLContext &	context,
		int	width,
		int	height )

Tries to allocates a buffer of the given size.

Note that a valid openGL context must be selected when you call this method, or it will fail.

initialise() [2/3]

bool OpenGLFrameBuffer::initialise	(	OpenGLContext &	context,
		const Image &	content )

Tries to allocates a buffer containing a copy of a given image.

Note that a valid openGL context must be selected when you call this method, or it will fail.

initialise() [3/3]

bool OpenGLFrameBuffer::initialise

(

OpenGLFrameBuffer &

other

)

Tries to allocate a copy of another framebuffer.

release()

void OpenGLFrameBuffer::release

(

)

Releases the buffer, if one has been allocated.

Any saved state that was created with saveAndRelease() will also be freed by this call.

saveAndRelease()

void OpenGLFrameBuffer::saveAndRelease

(

)

If the framebuffer is active, this will save a stashed copy of its contents in main memory, and will release the GL buffer.

After saving, the original state can be restored again by calling reloadSavedCopy().

reloadSavedCopy()

bool OpenGLFrameBuffer::reloadSavedCopy

(

OpenGLContext &

context

)

Restores the framebuffer content that was previously saved using saveAndRelease().

After saving to main memory, the original state can be restored by calling restoreToGPUMemory().

isValid()

bool OpenGLFrameBuffer::isValid ( ) const

noexcept

Returns true if a valid buffer has been allocated.

getWidth()

int OpenGLFrameBuffer::getWidth ( ) const

noexcept

Returns the width of the buffer.

getHeight()

int OpenGLFrameBuffer::getHeight ( ) const

noexcept

Returns the height of the buffer.

getTextureID()

GLuint OpenGLFrameBuffer::getTextureID ( ) const

noexcept

Returns the texture ID number for using this buffer as a texture.

makeCurrentRenderingTarget()

bool OpenGLFrameBuffer::makeCurrentRenderingTarget

(

)

Selects this buffer as the current OpenGL rendering target.

releaseAsRenderingTarget()

void OpenGLFrameBuffer::releaseAsRenderingTarget

(

)

Deselects this buffer as the current OpenGL rendering target.

getFrameBufferID()

GLuint OpenGLFrameBuffer::getFrameBufferID ( ) const

noexcept

Returns the ID of this framebuffer, or 0 if it isn't initialised.

getCurrentFrameBufferTarget()

static GLuint OpenGLFrameBuffer::getCurrentFrameBufferTarget ( )

staticnoexcept

Returns the current frame buffer ID for the current context.

clear()

void OpenGLFrameBuffer::clear

(

Colour

colour

)

Clears the framebuffer with the specified colour.

makeCurrentAndClear()

void OpenGLFrameBuffer::makeCurrentAndClear

(

)

Selects the framebuffer as the current target, and clears it to transparent.

readPixels()

bool OpenGLFrameBuffer::readPixels	(	PixelARGB *	targetData,
		const Rectangle< int > &	sourceArea )

Reads an area of pixels from the framebuffer into a 32-bit ARGB pixel array.

The lineStride is measured as a number of pixels, not bytes - pass a stride of 0 to indicate a packed array.

writePixels()

bool OpenGLFrameBuffer::writePixels	(	const PixelARGB *	srcData,
		const Rectangle< int > &	targetArea )

Writes an area of pixels into the framebuffer from a specified pixel array.

The lineStride is measured as a number of pixels, not bytes - pass a stride of 0 to indicate a packed array.

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

• juce_OpenGLFrameBuffer.h