This class generalize access to the GL context and available extensions. More...

#include <OpenGl_Context.hxx>

Inheritance diagram for OpenGl_Context:

Public Member Functions
	OpenGl_Context (const Handle< OpenGl_Caps > &theCaps=NULL)
	Empty constructor. You should call Init() to perform initialization with bound GL context. More...

virtual	~OpenGl_Context ()
	Destructor. More...

void	forcedRelease ()
	Release all resources, including shared ones. More...

void	Share (const Handle< OpenGl_Context > &theShareCtx)
	Share GL context resources. theShareCtx - handle to context to retrieve handles to shared resources. More...

Standard_Boolean	Init (const Standard_Boolean theIsCoreProfile=Standard_False)
	Initialize class from currently bound OpenGL context. Method should be called only once. More...

Standard_Boolean	IsValid () const

Standard_Boolean	Init (const Aspect_Drawable theWindow, const Aspect_Display theDisplay, const Aspect_RenderingContext theGContext, const Standard_Boolean theIsCoreProfile=Standard_False)
	Initialize class from specified window and rendering context. Method should be called only once. More...

Aspect_Drawable	Window () const

Standard_Boolean	CheckExtension (const char *theExtName) const
	Check if theExtName extension is supported by active GL context. More...

template<typename FuncType_t >
Standard_Boolean	FindProc (const char *theFuncName, FuncType_t &theFuncPtr)
	Auxiliary template to retrieve GL function pointer. Pointer to function retrieved from library is statically casted to requested type - there no way to check real signature of exported function. The context should be bound before call. More...

Standard_Boolean	IsGlGreaterEqual (const Standard_Integer theVerMajor, const Standard_Integer theVerMinor) const

Standard_Integer	VersionMajor () const
	Return cached GL version major number. More...

Standard_Integer	VersionMinor () const
	Return cached GL version minor number. More...

const OpenGl_GlFunctions *	Functions () const
	Access entire map of loaded OpenGL functions. More...

bool	ResetErrors (const bool theToPrintErrors=false)
	Clean up errors stack for this GL context (glGetError() in loop). More...

Standard_Boolean	IsCurrent () const
	This method uses system-dependent API to retrieve information about GL context bound to the current thread. More...

Standard_Boolean	MakeCurrent ()
	Activates current context. Class should be initialized with appropriate info. More...

void	SwapBuffers ()
	Swap front/back buffers for this GL context (should be activated before!). More...

Standard_Boolean	SetSwapInterval (const Standard_Integer theInterval)
	Setup swap interval (VSync). More...

Standard_Boolean	IsRender () const
	Return true if active mode is GL_RENDER (cached state) More...

Standard_Boolean	IsFeedback () const
	Return true if active mode is GL_FEEDBACK (cached state) More...

Standard_Size	AvailableMemory () const
	This function retrieves information from GL about free GPU memory that is: More...

TCollection_AsciiString	MemoryInfo () const
	This function retrieves information from GL about GPU memory and contains more vendor-specific values than AvailableMemory(). More...

void	MemoryInfo (TColStd_IndexedDataMapOfStringString &theDict) const
	This function retrieves information from GL about GPU memory. More...

void	DiagnosticInformation (TColStd_IndexedDataMapOfStringString &theDict, Graphic3d_DiagnosticInfo theFlags) const
	Fill in the dictionary with OpenGL info. Should be called with bound context. More...

const Handle< OpenGl_Resource > &	GetResource (const TCollection_AsciiString &theKey) const
	Access shared resource by its name. More...

template<typename TheHandleType >
Standard_Boolean	GetResource (const TCollection_AsciiString &theKey, TheHandleType &theValue) const
	Access shared resource by its name. More...

Standard_Boolean	ShareResource (const TCollection_AsciiString &theKey, const Handle< OpenGl_Resource > &theResource)
	Register shared resource. Notice that after registration caller shouldn't release it by himself - it will be automatically released on context destruction. More...

void	ReleaseResource (const TCollection_AsciiString &theKey, const Standard_Boolean theToDelay=Standard_False)
	Release shared resource. If there are more than one reference to this resource (also used by some other existing object) then call will be ignored. This means that current object itself should nullify handle before this call. Notice that this is unrecommended operation at all and should be used only in case of fat resources to release memory for other needs. More...

template<class T >
void	DelayedRelease (Handle< T > &theResource)
	Append resource to queue for delayed clean up. Resources in this queue will be released at next redraw call. More...

void	ReleaseDelayed ()
	Clean up the delayed release queue. More...

OpenGl_Clipping &	ChangeClipping ()

const OpenGl_Clipping &	Clipping () const

const Handle< OpenGl_ShaderManager > &	ShaderManager () const

Standard_Integer	TextureWrapClamp () const
	Either GL_CLAMP_TO_EDGE (1.2+) or GL_CLAMP (1.1). More...

Standard_Integer	MaxDegreeOfAnisotropy () const

Standard_Integer	MaxTextureSize () const

Standard_Integer	MaxMsaaSamples () const

Standard_Integer	MaxClipPlanes () const
	Get maximum number of clip planes supported by OpenGl. This value is implementation dependent. At least 6 planes should be supported by OpenGl (see specs). More...

Standard_Boolean	HasRayTracing () const

Standard_Boolean	HasRayTracingTextures () const

Standard_Boolean	HasRayTracingAdaptiveSampling () const

bool	ToUseVbo () const
	Returns true if VBO is supported and permitted. More...

Standard_Boolean	IsGlNormalizeEnabled () const

Standard_Boolean	SetGlNormalizeEnabled (Standard_Boolean isEnabled)
	Sets GL_NORMALIZE enabled or disabled. More...

Standard_Integer	PolygonMode () const

Standard_Integer	SetPolygonMode (const Standard_Integer theMode)
	Sets polygon rasterization mode (glPolygonMode() function). More...

bool	IsPolygonHatchEnabled () const

bool	SetPolygonHatchEnabled (const bool theIsEnabled)
	Sets enabled state of polygon hatching rasterization without affecting currently selected hatching pattern. More...

Standard_Integer	PolygonHatchStyle () const

Standard_Integer	SetPolygonHatchStyle (const Standard_Integer theStyle)
	Sets polygon hatch pattern. Zero-index value is a default alias for solid filling. More...

void	ApplyModelWorldMatrix ()
	Applies matrix stored in ModelWorldState to OpenGl. More...

void	ApplyWorldViewMatrix ()
	Applies matrix stored in WorldViewState to OpenGl. More...

void	ApplyModelViewMatrix ()
	Applies combination of matrices stored in ModelWorldState and WorldViewState to OpenGl. More...

void	ApplyProjectionMatrix ()
	Applies matrix stored in ProjectionState to OpenGl. More...

const Handle< Message_Messenger > &	Messenger () const

void	PushMessage (const unsigned int theSource, const unsigned int theType, const unsigned int theId, const unsigned int theSeverity, const TCollection_ExtendedString &theMessage)
	Callback for GL_ARB_debug_output extension. More...

Standard_Boolean	ExcludeMessage (const unsigned int theSource, const unsigned int theId)
	Adds a filter for messages with theId and theSource (GL_DEBUG_SOURCE_) More...

Standard_Boolean	IncludeMessage (const unsigned int theSource, const unsigned int theId)
	Removes a filter for messages with theId and theSource (GL_DEBUG_SOURCE_) More...

Standard_Boolean	HasStereoBuffers () const

Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor. More...

	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing. More...

Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter. More...

virtual	~Standard_Transient ()
	Destructor must be virtual. More...

virtual void	Delete () const
	Memory deallocator for transient classes. More...

virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object. More...

Standard_Boolean	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type. More...

Standard_Boolean	IsInstance (const Standard_CString theTypeName) const
	Returns a true value if this is an instance of TypeName. More...

Standard_Boolean	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. More...

Standard_Boolean	IsKind (const Standard_CString 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. More...

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. More...

Standard_Integer	GetRefCount () const
	Get the reference counter of this object. More...

void	IncrementRefCounter () const
	Increments the reference counter of this object. More...

Standard_Integer	DecrementRefCounter () const
	Decrements the reference counter of this object; returns the decremented value. More...

Static Public Member Functions
static Standard_Integer	GetPowerOfTwo (const Standard_Integer theNumber, const Standard_Integer theThreshold)
	Function for getting power of to number larger or equal to input number. More...

static void	ReadGlVersion (Standard_Integer &theGlVerMajor, Standard_Integer &theGlVerMinor)
	Read OpenGL version information from active context. More...

static Standard_Boolean	CheckExtension (const char theExtString, const char theExtName)
	Check if theExtName extension is in extensions string. More...

Static Public Member Functions inherited from Standard_Transient
static const char *	get_type_name ()
	Returns a type descriptor about this object. More...

static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class. More...

Data Fields
core profiles
OpenGl_GlCore11 *	core11
	OpenGL 1.1 core functionality. More...

OpenGl_GlCore11Fwd *	core11fwd
	OpenGL 1.1 without deprecated entry points. More...

OpenGl_GlCore15 *	core15
	OpenGL 1.5 core functionality. More...

OpenGl_GlCore15Fwd *	core15fwd
	OpenGL 1.5 without deprecated entry points. More...

OpenGl_GlCore20 *	core20
	OpenGL 2.0 core functionality (includes 1.5) More...

OpenGl_GlCore20Fwd *	core20fwd
	OpenGL 2.0 without deprecated entry points. More...

OpenGl_GlCore32 *	core32
	OpenGL 3.2 core profile. More...

OpenGl_GlCore32Back *	core32back
	OpenGL 3.2 backward compatibility profile. More...

OpenGl_GlCore33 *	core33
	OpenGL 3.3 core profile. More...

OpenGl_GlCore33Back *	core33back
	OpenGL 3.3 backward compatibility profile. More...

OpenGl_GlCore41 *	core41
	OpenGL 4.1 core profile. More...

OpenGl_GlCore41Back *	core41back
	OpenGL 4.1 backward compatibility profile. More...

OpenGl_GlCore42 *	core42
	OpenGL 4.2 core profile. More...

OpenGl_GlCore42Back *	core42back
	OpenGL 4.2 backward compatibility profile. More...

OpenGl_GlCore43 *	core43
	OpenGL 4.3 core profile. More...

OpenGl_GlCore43Back *	core43back
	OpenGL 4.3 backward compatibility profile. More...

OpenGl_GlCore44 *	core44
	OpenGL 4.4 core profile. More...

OpenGl_GlCore44Back *	core44back
	OpenGL 4.4 backward compatibility profile. More...

Handle< OpenGl_Caps >	caps
	context options More...

methods to alter or retrieve current state
const Standard_Integer *	Viewport () const
	Return cached viewport definition (x, y, width, height). More...

void	ResizeViewport (const Standard_Integer theRect[4])
	Resize the viewport (alias for glViewport). More...

Standard_Integer	ReadBuffer ()
	Return active read buffer. More...

void	SetReadBuffer (const Standard_Integer theReadBuffer)
	Switch read buffer, wrapper for ::glReadBuffer(). More...

Standard_Integer	DrawBuffer ()
	Return active draw buffer. More...

void	SetDrawBuffer (const Standard_Integer theDrawBuffer)
	Switch draw buffer, wrapper for ::glDrawBuffer(). More...

void	SetReadDrawBuffer (const Standard_Integer theBuffer)
	Switch read/draw buffers. More...

bool	ToCullBackFaces () const
	Return back face culling state. More...

void	SetCullBackFaces (bool theToEnable)
	Enable or disable back face culling (glEnable (GL_CULL_FACE)). More...

void	FetchState ()
	Fetch OpenGl context state. This class tracks value of several OpenGl state variables. Consulting the cached values is quicker than doing the same via OpenGl API. Call this method if any of the controlled OpenGl state variables has a possibility of being out-of-date. More...

const Handle< OpenGl_ShaderProgram > &	ActiveProgram () const

const Handle< OpenGl_Sampler > &	TextureSampler ()

Standard_Boolean	BindProgram (const Handle< OpenGl_ShaderProgram > &theProgram)
	Bind specified program to current context, or unbind previous one when NULL specified. More...

void	SetShadingMaterial (const OpenGl_AspectFace theAspect, const OpenGl_Vec4 theHighlightColor=NULL)
	Setup current shading material. More...

void	SetColor4fv (const OpenGl_Vec4 &theColor)
	Setup current color. More...

void	SetTypeOfLine (const Aspect_TypeOfLine theType, const Standard_ShortReal theFactor=1.0f)
	Setup type of line. More...

void	SetLineWidth (const Standard_ShortReal theWidth)
	Setup width of line. More...

void	SetPointSize (const Standard_ShortReal theSize)
	Setup point size. More...

void	SetPointSpriteOrigin ()
	Setup point sprite origin using GL_POINT_SPRITE_COORD_ORIGIN state: More...

void	SetTextureMatrix (const Handle< Graphic3d_TextureParams > &theParams)
	Setup texture matrix to active GLSL program or to FFP global state using glMatrixMode (GL_TEXTURE). More...

void	BindDefaultVao ()
	Bind default Vertex Array Object. More...

const Handle< OpenGl_FrameBuffer > &	DefaultFrameBuffer () const
	Default Frame Buffer Object. More...

Handle< OpenGl_FrameBuffer >	SetDefaultFrameBuffer (const Handle< OpenGl_FrameBuffer > &theFbo)
	Setup new Default Frame Buffer Object and return previously set. This call doesn't change Active FBO! More...

Standard_Boolean	IsDebugContext () const
	Return debug context initialization state. More...

void	EnableFeatures () const
	Return cached viewport definition (x, y, width, height). More...

void	DisableFeatures () const
	Return cached viewport definition (x, y, width, height). More...

void	SetResolutionRatio (const Standard_ShortReal theRatio)
	Set resolution ratio. Note that this method rounds to nearest integer. More...

extensions
Standard_Boolean	hasHighp
	highp in GLSL ES fragment shader is supported More...

Standard_Boolean	hasUintIndex
	GLuint for index buffer is supported (always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_element_index_uint) More...

Standard_Boolean	hasTexRGBA8
	always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_rgb8_rgba8 More...

Standard_Boolean	arbNPTW
	GL_ARB_texture_non_power_of_two. More...

Standard_Boolean	arbTexRG
	GL_ARB_texture_rg. More...

Standard_Boolean	arbTexFloat
	GL_ARB_texture_float (on desktop OpenGL - since 3.0 or as extension GL_ARB_texture_float; on OpenGL ES - since 3.0) More...

OpenGl_ArbTexBindless *	arbTexBindless
	GL_ARB_bindless_texture. More...

OpenGl_ArbTBO *	arbTBO
	GL_ARB_texture_buffer_object. More...

Standard_Boolean	arbTboRGB32
	GL_ARB_texture_buffer_object_rgb32 (3-component TBO), in core since 4.0. More...

OpenGl_ArbIns *	arbIns
	GL_ARB_draw_instanced. More...

OpenGl_ArbDbg *	arbDbg
	GL_ARB_debug_output. More...

OpenGl_ArbFBO *	arbFBO
	GL_ARB_framebuffer_object. More...

OpenGl_ArbFBOBlit *	arbFBOBlit
	glBlitFramebuffer function, moved out from OpenGl_ArbFBO structure for compatibility with OpenGL ES 2.0 More...

Standard_Boolean	extFragDepth
	GL_EXT_frag_depth on OpenGL ES 2.0 (gl_FragDepthEXT built-in variable, before OpenGL ES 3.0) More...

OpenGl_ExtGS *	extGS
	GL_EXT_geometry_shader4. More...

Standard_Boolean	extBgra
	GL_EXT_bgra or GL_EXT_texture_format_BGRA8888 on OpenGL ES. More...

Standard_Boolean	extAnis
	GL_EXT_texture_filter_anisotropic. More...

Standard_Boolean	extPDS
	GL_EXT_packed_depth_stencil. More...

Standard_Boolean	atiMem
	GL_ATI_meminfo. More...

Standard_Boolean	nvxMem
	GL_NVX_gpu_memory_info. More...

fields tracking current state
support object for managing shader programs
OpenGl_MatrixState< Standard_ShortReal >	ModelWorldState
	state of orientation matrix More...

OpenGl_MatrixState< Standard_ShortReal >	WorldViewState
	state of orientation matrix More...

OpenGl_MatrixState< Standard_ShortReal >	ProjectionState
	state of projection matrix More...

	DEFINE_STANDARD_RTTIEXT (OpenGl_Context, Standard_Transient) friend class OpenGl_Window
	state of orientation matrix More...

Additional Inherited Members
Public Types inherited from Standard_Transient
typedef void	base_type
	Returns a type descriptor about this object. More...

Detailed Description

This class generalize access to the GL context and available extensions.

Functions related to specific OpenGL version or extension are grouped into structures which can be accessed as fields of this class. The most simple way to check that required functionality is available - is NULL check for the group:

if (myContext->core20 != NULL)
{
  myGlProgram = myContext->core20->glCreateProgram();
  .. do more stuff ..
}
else
{
  .. compatibility with outdated configurations ..
}

Current implementation provide access to OpenGL core functionality up to 4.4 version (core12, core13, core14, core15, fields core20) as well as several extensions (arbTBO, arbFBO, etc.).

OpenGL context might be initialized in Core Profile. In this case deprecated functionality become unavailable. To make code easily adaptable to wide range of OpenGL versions, function sets related to each version has two kinds of suffixes:

"back" for version 3.2+. Represents function set for Backward-Compatible Profile. Function sets without this suffix represents core profile.
"fwd" for version 3.0-. Represents non-deprecated function set of earlier OpenGL versions, which are still available within OpenGL 3.2 Core Profile. Function sets without this suffix represents complete list of functions related to specific OpenGL version.

To select which core** function set should be used in specific case:

Determine the minimal OpenGL version required for implemented functionality and use it to access all functions. For example, if algorithm requires OpenGL 2.1+, it is better to write core20fwd->glEnable() rather than core11fwd->glEnable() for uniformity.
If functionality will work within Core Profile, use function sets with appropriate suffix.
Validate minimal requirements at initialization/creation time and omit checks within code where algorithm should be already initialized. Properly escape code incompatible with Core Profile. The simplest way to check Core Profile is "if (core11 == NULL)".

Simplified extensions classification:

prefixed with NV, AMD, ATI are vendor-specific (however may be provided by other vendors in some cases);
prefixed with EXT are accepted by 2+ vendors;
prefixed with ARB are accepted by Architecture Review Board and are candidates for inclusion into GL core functionality. Some functionality can be represented in several extensions simultaneously. In this case developer should be careful because different specification may differ in aspects (like enumeration values and error-handling).

Notice that some systems provide mechanisms to simultaneously incorporate with GL contexts with different capabilities. For this reason OpenGl_Context should be initialized and used for each GL context independently.

Constructor & Destructor Documentation

OpenGl_Context::OpenGl_Context ( const Handle< OpenGl_Caps > & theCaps = NULL )

Empty constructor. You should call Init() to perform initialization with bound GL context.

virtual OpenGl_Context::~OpenGl_Context ( )

virtual

Destructor.

Member Function Documentation

const Handle< OpenGl_ShaderProgram >& OpenGl_Context::ActiveProgram ( ) const

inline

Returns: active GLSL program

void OpenGl_Context::ApplyModelViewMatrix ( )

Applies combination of matrices stored in ModelWorldState and WorldViewState to OpenGl.

void OpenGl_Context::ApplyModelWorldMatrix ( )

Applies matrix stored in ModelWorldState to OpenGl.

void OpenGl_Context::ApplyProjectionMatrix ( )

Applies matrix stored in ProjectionState to OpenGl.

void OpenGl_Context::ApplyWorldViewMatrix ( )

Applies matrix stored in WorldViewState to OpenGl.

Standard_Size OpenGl_Context::AvailableMemory ( ) const

This function retrieves information from GL about free GPU memory that is:

OS-dependent. On some OS it is per-process and on others - for entire system.
Vendor-dependent. Currently available only on NVIDIA and AMD/ATi drivers only.
Numbers meaning may vary. You should use this info only for diagnostics purposes.
Returns
free GPU dedicated memory in bytes.

void OpenGl_Context::BindDefaultVao ( )

Bind default Vertex Array Object.

Standard_Boolean OpenGl_Context::BindProgram ( const Handle< OpenGl_ShaderProgram > & theProgram )

Bind specified program to current context, or unbind previous one when NULL specified.

Returns: true if some program is bound to context

OpenGl_Clipping& OpenGl_Context::ChangeClipping ( )

inline

Returns: tool for management of clippings within this context.

Standard_Boolean OpenGl_Context::CheckExtension ( const char * theExtName ) const

Check if theExtName extension is supported by active GL context.

static Standard_Boolean OpenGl_Context::CheckExtension	(	const char *	theExtString,
		const char *	theExtName
	)

static

Check if theExtName extension is in extensions string.

const OpenGl_Clipping& OpenGl_Context::Clipping ( ) const

inline

Returns: tool for management of clippings within this context.

const Handle< OpenGl_FrameBuffer >& OpenGl_Context::DefaultFrameBuffer ( ) const

inline

Default Frame Buffer Object.

OpenGl_Context::DEFINE_STANDARD_RTTIEXT	(	OpenGl_Context	,
		Standard_Transient
	)

state of orientation matrix

template<class T >

void OpenGl_Context::DelayedRelease ( Handle< T > & theResource )

inline

Append resource to queue for delayed clean up. Resources in this queue will be released at next redraw call.

void OpenGl_Context::DiagnosticInformation	(	TColStd_IndexedDataMapOfStringString &	theDict,
		Graphic3d_DiagnosticInfo	theFlags
	)		const

Fill in the dictionary with OpenGL info. Should be called with bound context.

void OpenGl_Context::DisableFeatures ( ) const

Return cached viewport definition (x, y, width, height).

Standard_Integer OpenGl_Context::DrawBuffer ( )

inline

Return active draw buffer.

void OpenGl_Context::EnableFeatures ( ) const

Return cached viewport definition (x, y, width, height).

Standard_Boolean OpenGl_Context::ExcludeMessage	(	const unsigned int	theSource,
		const unsigned int	theId
	)

Adds a filter for messages with theId and theSource (GL_DEBUG_SOURCE_)

void OpenGl_Context::FetchState ( )

Fetch OpenGl context state. This class tracks value of several OpenGl state variables. Consulting the cached values is quicker than doing the same via OpenGl API. Call this method if any of the controlled OpenGl state variables has a possibility of being out-of-date.

template<typename FuncType_t >

Standard_Boolean OpenGl_Context::FindProc	(	const char *	theFuncName,
		FuncType_t &	theFuncPtr
	)

inline

Auxiliary template to retrieve GL function pointer. Pointer to function retrieved from library is statically casted to requested type - there no way to check real signature of exported function. The context should be bound before call.

void OpenGl_Context::forcedRelease ( )

Release all resources, including shared ones.

const OpenGl_GlFunctions* OpenGl_Context::Functions ( ) const

inline

Access entire map of loaded OpenGL functions.

static Standard_Integer OpenGl_Context::GetPowerOfTwo	(	const Standard_Integer	theNumber,
		const Standard_Integer	theThreshold
	)

inlinestatic

Function for getting power of to number larger or equal to input number.

Parameters

theNumber	number to 'power of two'
theThreshold	upper threshold

Returns: power of two number

const Handle< OpenGl_Resource >& OpenGl_Context::GetResource ( const TCollection_AsciiString & theKey ) const

Access shared resource by its name.

Parameters

theKey - unique identifier;

Returns: handle to shared resource or NULL.

template<typename TheHandleType >

Standard_Boolean OpenGl_Context::GetResource	(	const TCollection_AsciiString &	theKey,
		TheHandleType &	theValue
	)		const

inline

Access shared resource by its name.

Parameters

theKey	- unique identifier;
theValue	- handle to fill;

Returns: true if resource was shared.

Standard_Boolean OpenGl_Context::HasRayTracing ( ) const

inline

Returns: TRUE if ray tracing mode is supported

Standard_Boolean OpenGl_Context::HasRayTracingAdaptiveSampling ( ) const

inline

Returns: TRUE if adaptive screen sampling in ray tracing mode is supported

Standard_Boolean OpenGl_Context::HasRayTracingTextures ( ) const

inline

Returns: TRUE if textures in ray tracing mode are supported

Standard_Boolean OpenGl_Context::HasStereoBuffers ( ) const

inline

Returns: true if OpenGl context supports left and right rendering buffers.

Standard_Boolean OpenGl_Context::IncludeMessage	(	const unsigned int	theSource,
		const unsigned int	theId
	)

Removes a filter for messages with theId and theSource (GL_DEBUG_SOURCE_)

Standard_Boolean OpenGl_Context::Init ( const Standard_Boolean theIsCoreProfile = Standard_False )

Initialize class from currently bound OpenGL context. Method should be called only once.

Returns: false if no GL context is bound to the current thread

Standard_Boolean OpenGl_Context::Init	(	const Aspect_Drawable	theWindow,
		const Aspect_Display	theDisplay,
		const Aspect_RenderingContext	theGContext,
		const Standard_Boolean	theIsCoreProfile = `Standard_False`
	)

Initialize class from specified window and rendering context. Method should be called only once.

Returns: false if OpenGL context can not be bound to specified window

Standard_Boolean OpenGl_Context::IsCurrent ( ) const

This method uses system-dependent API to retrieve information about GL context bound to the current thread.

Returns: true if current thread is bound to this GL context

Standard_Boolean OpenGl_Context::IsDebugContext ( ) const

inline

Return debug context initialization state.

Standard_Boolean OpenGl_Context::IsFeedback ( ) const

inline

Return true if active mode is GL_FEEDBACK (cached state)

Standard_Boolean OpenGl_Context::IsGlGreaterEqual	(	const Standard_Integer	theVerMajor,
		const Standard_Integer	theVerMinor
	)		const

inline

Returns: true if detected GL version is greater or equal to requested one.

Standard_Boolean OpenGl_Context::IsGlNormalizeEnabled ( ) const

inline

Returns: cached state of GL_NORMALIZE.

bool OpenGl_Context::IsPolygonHatchEnabled ( ) const

inline

Returns: cached enabled state of polygon hatching rasterization.

Standard_Boolean OpenGl_Context::IsRender ( ) const

inline

Return true if active mode is GL_RENDER (cached state)

Standard_Boolean OpenGl_Context::IsValid ( ) const

inline

Returns: true if this context is valid (has been initialized)

Standard_Boolean OpenGl_Context::MakeCurrent ( )

Activates current context. Class should be initialized with appropriate info.

Standard_Integer OpenGl_Context::MaxClipPlanes ( ) const

inline

Get maximum number of clip planes supported by OpenGl. This value is implementation dependent. At least 6 planes should be supported by OpenGl (see specs).

Returns: value for GL_MAX_CLIP_PLANES

Standard_Integer OpenGl_Context::MaxDegreeOfAnisotropy ( ) const

inline

Returns: maximum degree of anisotropy texture filter

Standard_Integer OpenGl_Context::MaxMsaaSamples ( ) const

inline

Returns: value for GL_MAX_SAMPLES

Standard_Integer OpenGl_Context::MaxTextureSize ( ) const

inline

Returns: value for GL_MAX_TEXTURE_SIZE

TCollection_AsciiString OpenGl_Context::MemoryInfo ( ) const

This function retrieves information from GL about GPU memory and contains more vendor-specific values than AvailableMemory().

void OpenGl_Context::MemoryInfo ( TColStd_IndexedDataMapOfStringString & theDict ) const

This function retrieves information from GL about GPU memory.

const Handle< Message_Messenger >& OpenGl_Context::Messenger ( ) const

inline

Returns: messenger instance

Standard_Integer OpenGl_Context::PolygonHatchStyle ( ) const

inline

Returns: cached state of polygon hatch type.

Standard_Integer OpenGl_Context::PolygonMode ( ) const

inline

Returns: cached state of polygon rasterization mode (glPolygonMode()).

void OpenGl_Context::PushMessage	(	const unsigned int	theSource,
		const unsigned int	theType,
		const unsigned int	theId,
		const unsigned int	theSeverity,
		const TCollection_ExtendedString &	theMessage
	)

Callback for GL_ARB_debug_output extension.

Parameters

theSource	message source within GL_DEBUG_SOURCE_ enumeration
theType	message type within GL_DEBUG_TYPE_ enumeration
theId	message ID within source
theSeverity	message severity within GL_DEBUG_SEVERITY_ enumeration
theMessage	the message itself

Standard_Integer OpenGl_Context::ReadBuffer ( )

inline

Return active read buffer.

static void OpenGl_Context::ReadGlVersion	(	Standard_Integer &	theGlVerMajor,
		Standard_Integer &	theGlVerMinor
	)

static

Read OpenGL version information from active context.

void OpenGl_Context::ReleaseDelayed ( )

Clean up the delayed release queue.

void OpenGl_Context::ReleaseResource	(	const TCollection_AsciiString &	theKey,
		const Standard_Boolean	theToDelay = `Standard_False`
	)

Release shared resource. If there are more than one reference to this resource (also used by some other existing object) then call will be ignored. This means that current object itself should nullify handle before this call. Notice that this is unrecommended operation at all and should be used only in case of fat resources to release memory for other needs.

Parameters

theKey	unique identifier
theToDelay	postpone release until next redraw call

bool OpenGl_Context::ResetErrors ( const bool theToPrintErrors = false )

Clean up errors stack for this GL context (glGetError() in loop).

Returns: true if some error has been cleared

void OpenGl_Context::ResizeViewport ( const Standard_Integer theRect[4] )

Resize the viewport (alias for glViewport).

Parameters

theRect viewport definition (x, y, width, height)

void OpenGl_Context::SetColor4fv ( const OpenGl_Vec4 & theColor )

Setup current color.

void OpenGl_Context::SetCullBackFaces ( bool theToEnable )

Enable or disable back face culling (glEnable (GL_CULL_FACE)).

Handle< OpenGl_FrameBuffer > OpenGl_Context::SetDefaultFrameBuffer ( const Handle< OpenGl_FrameBuffer > & theFbo )

Setup new Default Frame Buffer Object and return previously set. This call doesn't change Active FBO!

void OpenGl_Context::SetDrawBuffer ( const Standard_Integer theDrawBuffer )

Switch draw buffer, wrapper for ::glDrawBuffer().

Standard_Boolean OpenGl_Context::SetGlNormalizeEnabled ( Standard_Boolean isEnabled )

Sets GL_NORMALIZE enabled or disabled.

Returns: old value of the flag

void OpenGl_Context::SetLineWidth ( const Standard_ShortReal theWidth )

Setup width of line.

void OpenGl_Context::SetPointSize ( const Standard_ShortReal theSize )

Setup point size.

void OpenGl_Context::SetPointSpriteOrigin ( )

Setup point sprite origin using GL_POINT_SPRITE_COORD_ORIGIN state:

GL_UPPER_LEFT when GLSL program is active; flipping should be handled in GLSL program for compatibility with OpenGL ES
GL_LOWER_LEFT for FFP

bool OpenGl_Context::SetPolygonHatchEnabled ( const bool theIsEnabled )

Sets enabled state of polygon hatching rasterization without affecting currently selected hatching pattern.

Returns: previous state of polygon hatching mode.

Standard_Integer OpenGl_Context::SetPolygonHatchStyle ( const Standard_Integer theStyle )

Sets polygon hatch pattern. Zero-index value is a default alias for solid filling.

Parameters

the	type of hatch supported by base implementation of OpenGl_LineAttributes (Aspect_HatchStyle) or the type supported by custom implementation derived from OpenGl_LineAttributes class.

Returns: old type of hatch.

Standard_Integer OpenGl_Context::SetPolygonMode ( const Standard_Integer theMode )

Sets polygon rasterization mode (glPolygonMode() function).

Returns: old value of the rasterization mode.

void OpenGl_Context::SetReadBuffer ( const Standard_Integer theReadBuffer )

Switch read buffer, wrapper for ::glReadBuffer().

void OpenGl_Context::SetReadDrawBuffer ( const Standard_Integer theBuffer )

inline

Switch read/draw buffers.

void OpenGl_Context::SetResolutionRatio ( const Standard_ShortReal theRatio )

inline

Set resolution ratio. Note that this method rounds to nearest integer.

void OpenGl_Context::SetShadingMaterial	(	const OpenGl_AspectFace *	theAspect,
		const OpenGl_Vec4 *	theHighlightColor = `NULL`
	)

Setup current shading material.

Standard_Boolean OpenGl_Context::SetSwapInterval ( const Standard_Integer theInterval )

Setup swap interval (VSync).

void OpenGl_Context::SetTextureMatrix ( const Handle< Graphic3d_TextureParams > & theParams )

Setup texture matrix to active GLSL program or to FFP global state using glMatrixMode (GL_TEXTURE).

void OpenGl_Context::SetTypeOfLine	(	const Aspect_TypeOfLine	theType,
		const Standard_ShortReal	theFactor = `1.0f`
	)

Setup type of line.

const Handle< OpenGl_ShaderManager >& OpenGl_Context::ShaderManager ( ) const

inline

Returns: tool for management of shader programs within this context.

void OpenGl_Context::Share ( const Handle< OpenGl_Context > & theShareCtx )

Share GL context resources. theShareCtx - handle to context to retrieve handles to shared resources.

Standard_Boolean OpenGl_Context::ShareResource	(	const TCollection_AsciiString &	theKey,
		const Handle< OpenGl_Resource > &	theResource
	)

Register shared resource. Notice that after registration caller shouldn't release it by himself - it will be automatically released on context destruction.

Parameters

theKey	- unique identifier, shouldn't be empty;
theResource	- new resource to register, shouldn't be NULL.

void OpenGl_Context::SwapBuffers ( )

Swap front/back buffers for this GL context (should be activated before!).

const Handle< OpenGl_Sampler >& OpenGl_Context::TextureSampler ( )

inline

Returns: OpenGL sampler object used to override default texture parameters

Standard_Integer OpenGl_Context::TextureWrapClamp ( ) const

inline

Either GL_CLAMP_TO_EDGE (1.2+) or GL_CLAMP (1.1).

bool OpenGl_Context::ToCullBackFaces ( ) const

inline

Return back face culling state.

bool OpenGl_Context::ToUseVbo ( ) const

inline

Returns true if VBO is supported and permitted.

Standard_Integer OpenGl_Context::VersionMajor ( ) const

inline

Return cached GL version major number.

Standard_Integer OpenGl_Context::VersionMinor ( ) const

inline

Return cached GL version minor number.

const Standard_Integer* OpenGl_Context::Viewport ( ) const

inline

Return cached viewport definition (x, y, width, height).

Aspect_Drawable OpenGl_Context::Window ( ) const

inline

Returns: the window handle (GLXDrawable) currently bound to this OpenGL context

Field Documentation

OpenGl_ArbDbg* OpenGl_Context::arbDbg

GL_ARB_debug_output.

OpenGl_ArbFBO* OpenGl_Context::arbFBO

GL_ARB_framebuffer_object.

OpenGl_ArbFBOBlit* OpenGl_Context::arbFBOBlit

glBlitFramebuffer function, moved out from OpenGl_ArbFBO structure for compatibility with OpenGL ES 2.0

OpenGl_ArbIns* OpenGl_Context::arbIns

GL_ARB_draw_instanced.

Standard_Boolean OpenGl_Context::arbNPTW

GL_ARB_texture_non_power_of_two.

OpenGl_ArbTBO* OpenGl_Context::arbTBO

GL_ARB_texture_buffer_object.

Standard_Boolean OpenGl_Context::arbTboRGB32

GL_ARB_texture_buffer_object_rgb32 (3-component TBO), in core since 4.0.

OpenGl_ArbTexBindless* OpenGl_Context::arbTexBindless

GL_ARB_bindless_texture.

Standard_Boolean OpenGl_Context::arbTexFloat

GL_ARB_texture_float (on desktop OpenGL - since 3.0 or as extension GL_ARB_texture_float; on OpenGL ES - since 3.0)

Standard_Boolean OpenGl_Context::arbTexRG

GL_ARB_texture_rg.

Standard_Boolean OpenGl_Context::atiMem

GL_ATI_meminfo.

Handle< OpenGl_Caps > OpenGl_Context::caps

context options

OpenGl_GlCore11* OpenGl_Context::core11

OpenGL 1.1 core functionality.

OpenGl_GlCore11Fwd* OpenGl_Context::core11fwd

OpenGL 1.1 without deprecated entry points.

OpenGl_GlCore15* OpenGl_Context::core15

OpenGL 1.5 core functionality.

OpenGl_GlCore15Fwd* OpenGl_Context::core15fwd

OpenGL 1.5 without deprecated entry points.

OpenGl_GlCore20* OpenGl_Context::core20

OpenGL 2.0 core functionality (includes 1.5)

OpenGl_GlCore20Fwd* OpenGl_Context::core20fwd

OpenGL 2.0 without deprecated entry points.

OpenGl_GlCore32* OpenGl_Context::core32

OpenGL 3.2 core profile.

OpenGl_GlCore32Back* OpenGl_Context::core32back

OpenGL 3.2 backward compatibility profile.

OpenGl_GlCore33* OpenGl_Context::core33

OpenGL 3.3 core profile.

OpenGl_GlCore33Back* OpenGl_Context::core33back

OpenGL 3.3 backward compatibility profile.

OpenGl_GlCore41* OpenGl_Context::core41

OpenGL 4.1 core profile.

OpenGl_GlCore41Back* OpenGl_Context::core41back

OpenGL 4.1 backward compatibility profile.

OpenGl_GlCore42* OpenGl_Context::core42

OpenGL 4.2 core profile.

OpenGl_GlCore42Back* OpenGl_Context::core42back

OpenGL 4.2 backward compatibility profile.

OpenGl_GlCore43* OpenGl_Context::core43

OpenGL 4.3 core profile.

OpenGl_GlCore43Back* OpenGl_Context::core43back

OpenGL 4.3 backward compatibility profile.

OpenGl_GlCore44* OpenGl_Context::core44

OpenGL 4.4 core profile.

OpenGl_GlCore44Back* OpenGl_Context::core44back

OpenGL 4.4 backward compatibility profile.

Standard_Boolean OpenGl_Context::extAnis

GL_EXT_texture_filter_anisotropic.

Standard_Boolean OpenGl_Context::extBgra

GL_EXT_bgra or GL_EXT_texture_format_BGRA8888 on OpenGL ES.

Standard_Boolean OpenGl_Context::extFragDepth

GL_EXT_frag_depth on OpenGL ES 2.0 (gl_FragDepthEXT built-in variable, before OpenGL ES 3.0)

OpenGl_ExtGS* OpenGl_Context::extGS

GL_EXT_geometry_shader4.

Standard_Boolean OpenGl_Context::extPDS

GL_EXT_packed_depth_stencil.

Standard_Boolean OpenGl_Context::hasHighp

highp in GLSL ES fragment shader is supported

Standard_Boolean OpenGl_Context::hasTexRGBA8

always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_rgb8_rgba8

Standard_Boolean OpenGl_Context::hasUintIndex

GLuint for index buffer is supported (always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_element_index_uint)

OpenGl_MatrixState<Standard_ShortReal> OpenGl_Context::ModelWorldState

state of orientation matrix

Standard_Boolean OpenGl_Context::nvxMem

GL_NVX_gpu_memory_info.

OpenGl_MatrixState<Standard_ShortReal> OpenGl_Context::ProjectionState

state of projection matrix

OpenGl_MatrixState<Standard_ShortReal> OpenGl_Context::WorldViewState

state of orientation matrix

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

OpenGl_Context.hxx

OpenGl_Context Class Reference

Public Member Functions

Static Public Member Functions

Data Fields

methods to alter or retrieve current state

extensions

fields tracking current state

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation