ork::TransformFeedback Class Reference
[render]

A set of Buffer objects to collect the result of a transform feedback. More...

#include <TransformFeedback.h>

Inheritance diagram for ork::TransformFeedback:

Public Member Functions
	TransformFeedback ()
	Creates a new TransformFeedback object.
virtual	~TransformFeedback ()
	Deletes this TransformFeedback object.
void	reset ()
	Removes all the buffers associated with this object.
void	setVertexBuffer (int index, ptr< GPUBuffer > b)
	Attachs the given GPUBuffer to collect the transformed output varying of the given index.
void	setVertexBuffer (int index, ptr< GPUBuffer > b, GLuint offset, GLuint size)
	Attachs the given GPUBuffer to collect the transformed output varying of the given index.
void	transformFeedback (const TransformFeedback &tfb, int stream=0)
	Retransforms a mesh resulting from a previous transform feedback session.
Static Public Member Functions
static ptr< TransformFeedback >	getDefault ()
	Returns the default TransformFeedback instance.
static void	begin (ptr< FrameBuffer > fb, ptr< Program > transform, MeshMode m, ptr< TransformFeedback > tfb, bool rasterize)
	Starts a transform feedback session.
static void	transform (const MeshBuffers &mesh, GLint first, GLsizei count, GLsizei primCount=1, GLint base=0)
	Transforms a part of a mesh one or more times.
static void	multiTransform (const MeshBuffers &mesh, GLint firsts, GLsizei counts, GLsizei primCount, GLint *bases=0)
	Transforms several parts of a mesh.
static void	transformIndirect (const MeshBuffers &mesh, const Buffer &buf)
	Transforms a part of a mesh one or more times.
static void	pause ()
	Pauses the current transform feedback session.
static void	resume (ptr< TransformFeedback > tfb)
	Resumes the current transform feedback session.
static void	end ()
	Ends the current transform feedback session.

Detailed Description

A set of Buffer objects to collect the result of a transform feedback.

In OpenGL 3.3 only a single TransformFeedback instance can be used, the one returned by::getDefault. With OpenGL 4 other instances can be used, which can be created with the constructor. In any case, only one transform feedback can be performed at a time, with the static begin, transform and end methods.

Constructor & Destructor Documentation

ork::TransformFeedback::TransformFeedback ( )

Creates a new TransformFeedback object.

Only works with OpenGL 4.0 or more.

virtual ork::TransformFeedback::~TransformFeedback ( ) [virtual]

Deletes this TransformFeedback object.

Member Function Documentation

static void ork::TransformFeedback::begin	(	ptr< FrameBuffer >	fb,
		ptr< Program >	transform,
		MeshMode	m,
		ptr< TransformFeedback >	tfb,
		bool	rasterize
	)			`[static]`

Starts a transform feedback session.

Actual transforms are performed with the transform methods. The transformation is ended with the end() method. In OpenGL 4.0, pause and resume can be called between begin() and end(), for instance to change the TransformFeedback instance used to record the varyings.

Parameters:

	fb	the framebuffer to use for this session.
	transform	the program to use for this session.
	m	how the mesh vertices must be interpreted in transform methods.
	tfb	the set of buffers to use to store the results of the session, i.e., the transformed output varying variables.
	rasterize	true to rasterize the transformed primitives, or false to disable the rasterization stage during this session.

static void ork::TransformFeedback::end ( ) [static]

Ends the current transform feedback session.

static ptr<TransformFeedback> ork::TransformFeedback::getDefault ( ) [static]

Returns the default TransformFeedback instance.

static void ork::TransformFeedback::multiTransform	(	const MeshBuffers &	mesh,
		GLint *	firsts,
		GLsizei *	counts,
		GLsizei	primCount,
		GLint *	bases = `0`
	)			`[static]`

Transforms several parts of a mesh.

Each part is specified with a first and count parameter as in transform(). These values are passed in arrays of primCount values.

Parameters:

	mesh	the mesh to transform.
	firsts	an array of primCount 'first vertex' to draw, or an array of 'first indice' to draw if this mesh has indices.
	counts	an array of number of vertices to draw, or an array of number of indices to draw if this mesh has indices.
	primCount	the number of parts of this mesh to draw.
	bases	the base vertices to use. Only used for meshes with indices.

static void ork::TransformFeedback::pause ( ) [static]

Pauses the current transform feedback session.

Only available with OpenGL 4.0 or more.

void ork::TransformFeedback::reset ( )

Removes all the buffers associated with this object.

static void ork::TransformFeedback::resume ( ptr< TransformFeedback > tfb ) [static]

Resumes the current transform feedback session.

Only available with OpenGL 4.0 or more.

Parameters:

tfb

the set of buffers to use to store the results of the session, i.e., the transformed output varying variables.

void ork::TransformFeedback::setVertexBuffer	(	int	index,
		ptr< GPUBuffer >	b,
		GLuint	offset,
		GLuint	size
	)

Attachs the given GPUBuffer to collect the transformed output varying of the given index.

Parameters:

	index	the index of a recorded output varying variable.
	b	the GPUBuffer to use to store the recorded values of this varying.
	offset	the offset at which the first recorded value must be stored.
	size	the maximum size of the recorded values.

void ork::TransformFeedback::setVertexBuffer	(	int	index,
		ptr< GPUBuffer >	b
	)

Attachs the given GPUBuffer to collect the transformed output varying of the given index.

Parameters:

	index	the index of a recorded output varying variable.
	b	the GPUBuffer to use to store the recorded values of this varying.

static void ork::TransformFeedback::transform	(	const MeshBuffers &	mesh,
		GLint	first,
		GLsizei	count,
		GLsizei	primCount = `1`,
		GLint	base = `0`
	)			`[static]`

Transforms a part of a mesh one or more times.

Parameters:

	mesh	the mesh to transform.
	first	the first vertex to draw, or the first indice to draw if this mesh has indices.
	count	the number of vertices to draw, or the number of indices to draw if this mesh has indices.
	primCount	the number of times this mesh must be drawn (with geometry instancing).
	base	the base vertex to use. Only used for meshes with indices.

void ork::TransformFeedback::transformFeedback	(	const TransformFeedback &	tfb,
		int	stream = `0`
	)

Retransforms a mesh resulting from a previous transform feedback session.

Only available with OpenGL 4.0 or more.

Parameters:

	tfb	a TransformFeedback containing the results of a previous transform feedback session.
	stream	the stream to draw.

static void ork::TransformFeedback::transformIndirect	(	const MeshBuffers &	mesh,
		const Buffer &	buf
	)			`[static]`

Transforms a part of a mesh one or more times.

Parameters:

	mesh	the mesh to transform.
	buf	a CPU or GPU buffer containing the 'count', 'primCount', 'first' and 'base' parameters, in this order, as 32 bit integers.

ork::TransformFeedback Class Reference [render]

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

ork::TransformFeedback Class Reference
[render]