OpenGl_VertexBuffer Class Reference

Vertex Buffer Object - is a general storage object for vertex attributes (position, normal, color). Notice that you should use OpenGl_IndexBuffer specialization for array of indices. More...

#include <OpenGl_VertexBuffer.hxx>

Inheritance diagram for OpenGl_VertexBuffer:

Public Member Functions
	OpenGl_VertexBuffer ()
	Create uninitialized VBO.
	~OpenGl_VertexBuffer () override
	Destroy object.
unsigned int	GetTarget () const override
	Return buffer target GL_ARRAY_BUFFER.
void	BindVertexAttrib (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theAttribLoc) const
	Bind this VBO to active GLSL program.
void	UnbindVertexAttrib (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theAttribLoc) const
	Unbind any VBO from active GLSL program.
void	BindAttribute (const occ::handle< OpenGl_Context > &theCtx, const Graphic3d_TypeOfAttribute theMode) const
	Bind this VBO and enable specified attribute in OpenGl_Context::ActiveProgram() or FFP.
void	UnbindAttribute (const occ::handle< OpenGl_Context > &theCtx, const Graphic3d_TypeOfAttribute theMode) const
	Unbind this VBO and disable specified attribute in OpenGl_Context::ActiveProgram() or FFP.
methods for interleaved attributes array
Returns true if buffer contains per-vertex color attribute
virtual bool	HasColorAttribute () const
virtual bool	HasNormalAttribute () const
virtual void	BindAllAttributes (const occ::handle< OpenGl_Context > &theGlCtx) const
	Bind all vertex attributes to active program OpenGl_Context::ActiveProgram() or for FFP. Default implementation does nothing.
virtual void	BindPositionAttribute (const occ::handle< OpenGl_Context > &theGlCtx) const
	Bind vertex position attribute only. Default implementation does nothing.
virtual void	UnbindAllAttributes (const occ::handle< OpenGl_Context > &theGlCtx) const
	Unbind all vertex attributes. Default implementation does nothing.
Public Member Functions inherited from OpenGl_Buffer
	OpenGl_Buffer ()
	Create uninitialized buffer.
	~OpenGl_Buffer () override
	Destroy object.
virtual bool	IsVirtual () const
	Return TRUE if this is a virtual (for backward compatibility) VBO object.
bool	IsValid () const
unsigned int	GetComponentsNb () const
int	GetElemsNb () const
void	SetElemsNb (int theNbElems)
	Overrides the number of vertex attributes / number of vertexes. It is up to user specifying this number correct (e.g. below initial value)!
unsigned int	GetDataType () const
uint8_t *	GetDataOffset () const
virtual bool	Create (const occ::handle< OpenGl_Context > &theGlCtx)
	Creates buffer object name (id) if not yet generated. Data should be initialized by another method.
void	Release (OpenGl_Context *theGlCtx) override
	Destroy object - will release GPU memory if any.
virtual void	Bind (const occ::handle< OpenGl_Context > &theGlCtx) const
	Bind this buffer object.
virtual void	Unbind (const occ::handle< OpenGl_Context > &theGlCtx) const
	Unbind this buffer object.
bool	Init (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theComponentsNb, const int theElemsNb, const float *theData)
	Notice that buffer object will be unbound after this call.
bool	Init (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theComponentsNb, const int theElemsNb, const unsigned int *theData)
	Notice that buffer object will be unbound after this call.
bool	Init (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theComponentsNb, const int theElemsNb, const unsigned short *theData)
	Notice that buffer object will be unbound after this call.
bool	Init (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theComponentsNb, const int theElemsNb, const uint8_t *theData)
	Notice that buffer object will be unbound after this call.
bool	SubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, const float *theData)
	Notice that buffer object will be unbound after this call. Function replaces portion of data within this buffer object using glBufferSubData(). The buffer object should be initialized before call.
bool	GetSubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, float *theData)
	Read back buffer sub-range. Notice that buffer object will be unbound after this call. Function reads portion of data from this buffer object using glGetBufferSubData().
bool	SubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, const unsigned int *theData)
	Notice that buffer object will be unbound after this call. Function replaces portion of data within this buffer object using glBufferSubData(). The buffer object should be initialized before call.
bool	GetSubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, unsigned int *theData)
	Read back buffer sub-range. Notice that buffer object will be unbound after this call. Function reads portion of data from this buffer object using glGetBufferSubData().
bool	SubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, const unsigned short *theData)
	Notice that buffer object will be unbound after this call. Function replaces portion of data within this buffer object using glBufferSubData(). The buffer object should be initialized before call.
bool	GetSubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, unsigned short *theData)
	Read back buffer sub-range. Notice that buffer object will be unbound after this call. Function reads portion of data from this buffer object using glGetBufferSubData().
bool	SubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, const uint8_t *theData)
	Notice that buffer object will be unbound after this call. Function replaces portion of data within this buffer object using glBufferSubData(). The buffer object should be initialized before call.
bool	GetSubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, uint8_t *theData)
	Read back buffer sub-range. Notice that buffer object will be unbound after this call. Function reads portion of data from this buffer object using glGetBufferSubData().
size_t	EstimatedDataSize () const override
	offset to data
virtual bool	init (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theComponentsNb, const int theElemsNb, const void *theData, const unsigned int theDataType, const int theStride)
	Initialize buffer with new data.
bool	init (const occ::handle< OpenGl_Context > &theGlCtx, const unsigned int theComponentsNb, const int theElemsNb, const void *theData, const unsigned int theDataType)
	Initialize buffer with new data.
virtual bool	subData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, const void *theData, const unsigned int theDataType)
	Update part of the buffer with new data.
virtual bool	getSubData (const occ::handle< OpenGl_Context > &theGlCtx, const int theElemFrom, const int theElemsNb, void *theData, const unsigned int theDataType)
	Read back buffer sub-range.
void	DumpJson (Standard_OStream &theOStream, int theDepth=-1) const override
	Dumps the content of me into the stream.
Public Member Functions inherited from OpenGl_Resource
	OpenGl_Resource ()
	Empty constructor.
	~OpenGl_Resource () override
	Destructor. Inheritors should call Clean (NULL) within it.
Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor.
	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing.
Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter.
virtual	~Standard_Transient ()=default
	Destructor must be virtual.
virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.
bool	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.
bool	IsInstance (const char *const theTypeName) const
	Returns a true value if this is an instance of TypeName.
bool	IsKind (const opencascade::handle< Standard_Type > &theType) const
	Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
bool	IsKind (const char *const theTypeName) const
	Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
Standard_Transient *	This () const
	Returns non-const pointer to this object (like const_cast). For protection against creating handle to objects allocated in stack or call from constructor, it will raise exception Standard_ProgramError if reference counter is zero.
int	GetRefCount () const noexcept
	Get the reference counter of this object.
void	IncrementRefCounter () noexcept
	Increments the reference counter of this object. Uses relaxed memory ordering since incrementing only requires atomicity, not synchronization with other memory operations.
int	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value. Uses release ordering for the decrement to ensure all writes to the object are visible before the count reaches zero. An acquire fence is added only when the count reaches zero, ensuring proper synchronization before deletion. This is more efficient than using acq_rel for every decrement.
virtual void	Delete () const
	Memory deallocator for transient classes.

advanced methods
Setup array pointer - either for active GLSL program OpenGl_Context::ActiveProgram() or for FFP using bindFixed() when no program bound.
static void	bindAttribute (const occ::handle< OpenGl_Context > &theGlCtx, const Graphic3d_TypeOfAttribute theMode, const int theNbComp, const unsigned int theDataType, const int theStride, const void *theOffset)
	Disable GLSL array pointer - either for active GLSL program OpenGl_Context::ActiveProgram() or for FFP using unbindFixed() when no program bound.
static void	unbindAttribute (const occ::handle< OpenGl_Context > &theGlCtx, const Graphic3d_TypeOfAttribute theMode)
	Disable GLSL array pointer - either for active GLSL program OpenGl_Context::ActiveProgram() or for FFP using unbindFixed() when no program bound.

Additional Inherited Members
typedef void	base_type
	Returns a type descriptor about this object.
Static Public Member Functions inherited from OpenGl_Buffer
static TCollection_AsciiString	FormatTarget (unsigned int theTarget)
	Format VBO target enumeration value.
static size_t	sizeOfGlType (unsigned int theType)
static constexpr const char *	get_type_name ()
	Returns a type descriptor about this object.
static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class.
Static Public Attributes inherited from OpenGl_Buffer
static const unsigned int	NO_BUFFER = 0
	Helpful constants.
void	BindBufferBase (const occ::handle< OpenGl_Context > &theGlCtx, unsigned int theIndex)
	Binds a buffer object to an indexed buffer target. Wrapper for glBindBufferBase().
void	UnbindBufferBase (const occ::handle< OpenGl_Context > &theGlCtx, unsigned int theIndex)
	Unbinds a buffer object from an indexed buffer target. Wrapper for glBindBufferBase().
void	BindBufferRange (const occ::handle< OpenGl_Context > &theGlCtx, unsigned int theIndex, const intptr_t theOffset, const size_t theSize)
	Binds a buffer object to an indexed buffer target with specified offset and size. Wrapper for glBindBufferRange().
uint8_t *	myOffset
	offset to data
unsigned int	myBufferId
	VBO name (index).
unsigned int	myComponentsNb
	Number of components per generic vertex attribute, must be 1, 2, 3, or 4.
int	myElemsNb
	Number of vertex attributes / number of vertices.
unsigned int	myDataType
	Data type (GL_FLOAT, GL_UNSIGNED_INT, GL_UNSIGNED_BYTE etc.).

Detailed Description

Vertex Buffer Object - is a general storage object for vertex attributes (position, normal, color). Notice that you should use OpenGl_IndexBuffer specialization for array of indices.

Constructor & Destructor Documentation

OpenGl_VertexBuffer()

OpenGl_VertexBuffer::OpenGl_VertexBuffer

(

)

Create uninitialized VBO.

~OpenGl_VertexBuffer()

OpenGl_VertexBuffer::~OpenGl_VertexBuffer ( )

override

Destroy object.

Member Function Documentation

BindAllAttributes()

virtual void OpenGl_VertexBuffer::BindAllAttributes ( const occ::handle< OpenGl_Context > & theGlCtx ) const

virtual

Bind all vertex attributes to active program OpenGl_Context::ActiveProgram() or for FFP. Default implementation does nothing.

BindAttribute()

void OpenGl_VertexBuffer::BindAttribute ( const occ::handle< OpenGl_Context > & theCtx, const Graphic3d_TypeOfAttribute theMode ) const

inline

Bind this VBO and enable specified attribute in OpenGl_Context::ActiveProgram() or FFP.

Parameters

theGlCtx	- handle to bound GL context;
theMode	- array mode (GL_VERTEX_ARRAY, GL_NORMAL_ARRAY, GL_COLOR_ARRAY, GL_INDEX_ARRAY, GL_TEXTURE_COORD_ARRAY).

bindAttribute()

void OpenGl_VertexBuffer::bindAttribute ( const occ::handle< OpenGl_Context > & theGlCtx, const Graphic3d_TypeOfAttribute theMode, const int theNbComp, const unsigned int theDataType, const int theStride, const void * theOffset )

static

Disable GLSL array pointer - either for active GLSL program OpenGl_Context::ActiveProgram() or for FFP using unbindFixed() when no program bound.

BindPositionAttribute()

virtual void OpenGl_VertexBuffer::BindPositionAttribute ( const occ::handle< OpenGl_Context > & theGlCtx ) const

virtual

Bind vertex position attribute only. Default implementation does nothing.

BindVertexAttrib()

void OpenGl_VertexBuffer::BindVertexAttrib	(	const occ::handle< OpenGl_Context > &	theGlCtx,
		const unsigned int	theAttribLoc ) const

Bind this VBO to active GLSL program.

GetTarget()

unsigned int OpenGl_VertexBuffer::GetTarget ( ) const

overridevirtual

Return buffer target GL_ARRAY_BUFFER.

Implements OpenGl_Buffer.

HasColorAttribute()

virtual bool OpenGl_VertexBuffer::HasColorAttribute ( ) const

virtual

Returns

true if buffer contains per-vertex normal attribute

HasNormalAttribute()

virtual bool OpenGl_VertexBuffer::HasNormalAttribute ( ) const

virtual

Returns

true if buffer contains per-vertex normal attribute

UnbindAllAttributes()

virtual void OpenGl_VertexBuffer::UnbindAllAttributes ( const occ::handle< OpenGl_Context > & theGlCtx ) const

virtual

Unbind all vertex attributes. Default implementation does nothing.

UnbindAttribute()

void OpenGl_VertexBuffer::UnbindAttribute ( const occ::handle< OpenGl_Context > & theCtx, const Graphic3d_TypeOfAttribute theMode ) const

inline

Unbind this VBO and disable specified attribute in OpenGl_Context::ActiveProgram() or FFP.

Parameters

theCtx	handle to bound GL context
theMode	array mode

unbindAttribute()

void OpenGl_VertexBuffer::unbindAttribute ( const occ::handle< OpenGl_Context > & theGlCtx, const Graphic3d_TypeOfAttribute theMode )

static

Disable GLSL array pointer - either for active GLSL program OpenGl_Context::ActiveProgram() or for FFP using unbindFixed() when no program bound.

UnbindVertexAttrib()

void OpenGl_VertexBuffer::UnbindVertexAttrib	(	const occ::handle< OpenGl_Context > &	theGlCtx,
		const unsigned int	theAttribLoc ) const

Unbind any VBO from active GLSL program.

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

• OpenGl_VertexBuffer.hxx