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

#include <OpenGl_Context.hxx>

Inheritance diagram for OpenGl_Context:

Public Types
typedef NCollection_Shared< NCollection_DataMap< TCollection_AsciiString, Handle< OpenGl_Resource > > >	OpenGl_ResourcesMap

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

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

virtual	~OpenGl_Context ()
	Destructor.

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

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

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

Standard_Boolean	IsValid () const

Standard_Boolean	Init (const Aspect_Drawable theSurface, const Aspect_Display theDisplay, const Aspect_RenderingContext theContext, const Standard_Boolean theIsCoreProfile=Standard_False)
	Initialize class from specified surface and rendering context. Method should be called only once. The meaning of parameters is platform-specific.

Aspect_Drawable	Window () const
	Return window handle currently bound to this OpenGL context (EGLSurface \| HWND \| GLXDrawable).

Aspect_Display	GetDisplay () const
	Return display / window device context (EGLDisplay \| HDC \| Display*).

Aspect_RenderingContext	RenderingContext () const
	Return rendering context (EGLContext \| HGLRC \| GLXContext \| EAGLContext* \| NSOpenGLContext*).

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

template<typename FuncType_t >
Standard_Boolean	FindProcVerbose (const char &theLastFailFuncName, 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.

template<typename FuncType_t >
Standard_Boolean	FindProc (const char *theFuncName, FuncType_t &theFuncPtr)
	Auxiliary template to retrieve GL function pointer. Same as FindProcVerbose() but without auxiliary last function name argument.

Aspect_GraphicsLibrary	GraphicsLibrary () const
	Return active graphics library.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

void	WindowBufferBits (Graphic3d_Vec4i &theColorBits, Graphic3d_Vec2i &theDepthStencilBits) const
	Fetches information about window buffer pixel format.

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

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

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.

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.

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.

void	ReleaseDelayed ()
	Clean up the delayed release queue.

const OpenGl_ResourcesMap &	SharedResources () const
	Return map of shared resources.

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).

Standard_Boolean	HasTextureBaseLevel () const

const Handle< Image_SupportedFormats > &	SupportedTextureFormats () const
	Return map of supported texture formats.

Standard_Integer	MaxDegreeOfAnisotropy () const

Standard_Integer	MaxTextureSize () const

Standard_Integer	MaxCombinedTextureUnits () const

Standard_Integer	MaxTextureUnitsFFP () const
	This method returns the multi-texture limit for obsolete fixed-function pipeline. Use MaxCombinedTextureUnits() instead for limits for using programmable pipeline.

Graphic3d_TextureUnit	SpriteTextureUnit () const
	Return texture unit to be used for sprites (Graphic3d_TextureUnit_PointSprite by default).

Standard_Boolean	HasTextureMultisampling () const

Standard_Integer	MaxMsaaSamples () const

Standard_Integer	MaxDumpSizeX () const

Standard_Integer	MaxDumpSizeY () const

Standard_Integer	MaxDrawBuffers () const

Standard_Integer	MaxColorAttachments () 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).

Standard_Boolean	HasRayTracing () const

Standard_Boolean	HasRayTracingTextures () const

Standard_Boolean	HasRayTracingAdaptiveSampling () const

Standard_Boolean	HasRayTracingAdaptiveSamplingAtomic () const

bool	HasSRGB () const
	Returns TRUE if sRGB rendering is supported.

bool	ToRenderSRGB () const
	Returns TRUE if sRGB rendering is supported and permitted.

bool	IsWindowSRGB () const
	Returns TRUE if window/surface buffer is sRGB-ready.

void	SetWindowSRGB (bool theIsSRgb)
	Overrides if window/surface buffer is sRGB-ready or not (initialized with the context).

bool	IsWindowDeepColor () const
	Returns TRUE if window/surface buffer has deep color (10bit per component / 30bit RGB) or better precision.

OpenGl_Vec4	Vec4FromQuantityColor (const OpenGl_Vec4 &theColor) const
	Convert Quantity_ColorRGBA into vec4 with conversion or no conversion into non-linear sRGB basing on ToRenderSRGB() flag.

const OpenGl_Vec4 &	Vec4LinearFromQuantityColor (const OpenGl_Vec4 &theColor) const
	Convert Quantity_ColorRGBA into vec4. Quantity_Color is expected to be linear RGB, hence conversion is NOT required.

OpenGl_Vec4	Vec4sRGBFromQuantityColor (const OpenGl_Vec4 &theColor) const
	Convert Quantity_ColorRGBA (linear RGB) into non-linear sRGB vec4.

Standard_Boolean	HasPBR () const
	Returns TRUE if PBR shading model is supported. Basically, feature requires OpenGL 3.0+ / OpenGL ES 3.0+ hardware; more precisely:

Graphic3d_TextureUnit	PBREnvLUTTexUnit () const
	Returns texture unit where Environment Lookup Table is expected to be bound, or 0 if PBR is unavailable.

Graphic3d_TextureUnit	PBRDiffIBLMapSHTexUnit () const
	Returns texture unit where Diffuse (irradiance) IBL map's spherical harmonics coefficients is expected to be bound, or 0 if PBR is unavailable.

Graphic3d_TextureUnit	PBRSpecIBLMapTexUnit () const
	Returns texture unit where Specular IBL map is expected to be bound, or 0 if PBR is unavailable.

Graphic3d_TextureUnit	ShadowMapTexUnit () const
	Returns texture unit where shadow map is expected to be bound, or 0 if unavailable.

Graphic3d_TextureUnit	DepthPeelingDepthTexUnit () const
	Returns texture unit for occDepthPeelingDepth within enabled Depth Peeling.

Graphic3d_TextureUnit	DepthPeelingFrontColorTexUnit () const
	Returns texture unit for occDepthPeelingFrontColor within enabled Depth Peeling.

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

Standard_Boolean	IsGlNormalizeEnabled () const

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

Standard_Integer	PolygonMode () const

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

bool	IsPolygonHatchEnabled () const

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

Standard_Integer	PolygonHatchStyle () const

Standard_Integer	SetPolygonHatchStyle (const Handle< Graphic3d_HatchStyle > &theStyle)
	Sets polygon hatch pattern. Zero-index value is a default alias for solid filling.

void	SetPolygonOffset (const Graphic3d_PolygonOffset &theOffset)
	Sets and applies current polygon offset.

const Graphic3d_PolygonOffset &	PolygonOffset () const
	Returns currently applied polygon offset parameters.

const Handle< Graphic3d_Camera > &	Camera () const
	Returns camera object.

void	SetCamera (const Handle< Graphic3d_Camera > &theCamera)
	Sets camera object to the context and update matrices.

void	ApplyModelWorldMatrix ()
	Applies matrix into shader manager stored in ModelWorldState to OpenGl. In "model -> world -> view -> projection" it performs: model -> world.

void	ApplyWorldViewMatrix ()
	Applies matrix stored in WorldViewState to OpenGl. In "model -> world -> view -> projection" it performs: model -> world -> view, where model -> world is identical matrix.

void	ApplyModelViewMatrix ()
	Applies combination of matrices stored in ModelWorldState and WorldViewState to OpenGl. In "model -> world -> view -> projection" it performs: model -> world -> view.

void	ApplyProjectionMatrix ()
	Applies matrix stored in ProjectionState to OpenGl. In "model -> world -> view -> projection" it performs: view -> projection.

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.

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

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

Standard_Boolean	HasStereoBuffers () const

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 ()
	Destructor must be virtual.

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

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

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

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.

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.

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.

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

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

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

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

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.

static TCollection_AsciiString	FormatGlEnumHex (int theGlEnum)
	Format GL constant as hex value 0xABCD.

static TCollection_AsciiString	FormatPointer (const void *thePtr)
	Format pointer as hex value 0xABCD.

static TCollection_AsciiString	FormatSize (Standard_Size theSize)
	Format size value.

static TCollection_AsciiString	FormatGlError (int theGlError)
	Return text description of GL error.

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

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

Static Public Member Functions inherited from Standard_Transient
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.

Data Fields
core profiles
OpenGl_GlCore11 *	core11ffp
	OpenGL 1.1 core functionality.

OpenGl_GlCore11Fwd *	core11fwd
	OpenGL 1.1 without deprecated entry points.

OpenGl_GlCore15 *	core15
	OpenGL 1.5 without deprecated entry points.

OpenGl_GlCore20 *	core20
	OpenGL 2.0 without deprecated entry points.

OpenGl_GlCore30 *	core30
	OpenGL 3.0 without deprecated entry points.

OpenGl_GlCore32 *	core32
	OpenGL 3.2 core profile.

OpenGl_GlCore33 *	core33
	OpenGL 3.3 core profile.

OpenGl_GlCore41 *	core41
	OpenGL 4.1 core profile.

OpenGl_GlCore42 *	core42
	OpenGL 4.2 core profile.

OpenGl_GlCore43 *	core43
	OpenGL 4.3 core profile.

OpenGl_GlCore44 *	core44
	OpenGL 4.4 core profile.

OpenGl_GlCore45 *	core45
	OpenGL 4.5 core profile.

OpenGl_GlCore46 *	core46
	OpenGL 4.6 core profile.

OpenGl_GlCore15 *	core15fwd
	obsolete entry left for code portability; core15 should be used instead

OpenGl_GlCore20 *	core20fwd
	obsolete entry left for code portability; core20 should be used instead

Handle< OpenGl_Caps >	caps
	context options

extensions
Standard_Boolean	hasGetBufferData
	flag indicating if GetBufferSubData() is supported

Standard_Boolean	hasPackRowLength
	supporting of GL_PACK_ROW_LENGTH parameters (any desktop OpenGL; OpenGL ES 3.0)

Standard_Boolean	hasUnpackRowLength
	supporting of GL_UNPACK_ROW_LENGTH parameters (any desktop OpenGL; OpenGL ES 3.0)

Standard_Boolean	hasHighp
	highp in GLSL ES fragment shader is supported

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)

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

Standard_Boolean	hasTexFloatLinear
	texture-filterable state for 32-bit floating texture formats (always on desktop, GL_OES_texture_float_linear within OpenGL ES)

Standard_Boolean	hasTexSRGB
	sRGB texture formats (desktop OpenGL 2.1, OpenGL ES 3.0 or OpenGL ES 2.0 + GL_EXT_sRGB)

Standard_Boolean	hasFboSRGB
	sRGB FBO render targets (desktop OpenGL 2.1, OpenGL ES 3.0)

Standard_Boolean	hasSRGBControl
	sRGB write control (any desktop OpenGL, OpenGL ES + GL_EXT_sRGB_write_control extension)

Standard_Boolean	hasFboRenderMipmap
	FBO render target could be non-zero mipmap level of texture.

OpenGl_FeatureFlag	hasFlatShading
	Complex flag indicating support of Flat shading (Graphic3d_TypeOfShadingModel_Phong) (always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_standard_derivatives)

OpenGl_FeatureFlag	hasGlslBitwiseOps
	GLSL supports bitwise operations; OpenGL 3.0 / OpenGL ES 3.0 (GLSL 130 / GLSL ES 300) or OpenGL 2.1 + GL_EXT_gpu_shader4.

OpenGl_FeatureFlag	hasDrawBuffers
	Complex flag indicating support of multiple draw buffers (desktop OpenGL 2.0, OpenGL ES 3.0, GL_ARB_draw_buffers, GL_EXT_draw_buffers)

OpenGl_FeatureFlag	hasFloatBuffer
	Complex flag indicating support of float color buffer format (desktop OpenGL 3.0, GL_ARB_color_buffer_float, GL_EXT_color_buffer_float)

OpenGl_FeatureFlag	hasHalfFloatBuffer
	Complex flag indicating support of half-float color buffer format (desktop OpenGL 3.0, GL_ARB_color_buffer_float, GL_EXT_color_buffer_half_float)

OpenGl_FeatureFlag	hasSampleVariables
	Complex flag indicating support of MSAA variables in GLSL shader (desktop OpenGL 4.0, GL_ARB_sample_shading)

OpenGl_FeatureFlag	hasGeometryStage
	Complex flag indicating support of Geometry shader (desktop OpenGL 3.2, OpenGL ES 3.2, GL_EXT_geometry_shader)

Standard_Boolean	arbDrawBuffers
	GL_ARB_draw_buffers.

Standard_Boolean	arbNPTW
	GL_ARB_texture_non_power_of_two.

Standard_Boolean	arbTexRG
	GL_ARB_texture_rg.

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);.

OpenGl_ArbSamplerObject *	arbSamplerObject
	GL_ARB_sampler_objects (on desktop OpenGL - since 3.3 or as extension GL_ARB_sampler_objects; on OpenGL ES - since 3.0)

OpenGl_ArbTexBindless *	arbTexBindless
	GL_ARB_bindless_texture.

OpenGl_ArbTBO *	arbTBO
	GL_ARB_texture_buffer_object (on desktop OpenGL - since 3.1 or as extension GL_ARB_texture_buffer_object; on OpenGL ES - since 3.2)

Standard_Boolean	arbTboRGB32
	GL_ARB_texture_buffer_object_rgb32 (3-component TBO), in core since 4.0 (on OpenGL ES - since 3.2)

Standard_Boolean	arbClipControl
	GL_ARB_clip_control, in core since 4.5.

OpenGl_ArbIns *	arbIns
	GL_ARB_draw_instanced (on desktop OpenGL - since 3.1 or as extension GL_ARB_draw_instanced; on OpenGL ES - since 3.0 or as extension GL_ANGLE_instanced_arrays to WebGL 1.0)

OpenGl_ArbDbg *	arbDbg
	GL_ARB_debug_output (on desktop OpenGL - since 4.3 or as extension GL_ARB_debug_output; on OpenGL ES - since 3.2 or as extension GL_KHR_debug)

OpenGl_ArbFBO *	arbFBO
	GL_ARB_framebuffer_object.

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

Standard_Boolean	arbSampleShading
	GL_ARB_sample_shading.

Standard_Boolean	arbDepthClamp
	GL_ARB_depth_clamp (on desktop OpenGL - since 3.2 or as extensions GL_ARB_depth_clamp,NV_depth_clamp; unavailable on OpenGL ES)

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

Standard_Boolean	extDrawBuffers
	GL_EXT_draw_buffers.

OpenGl_ExtGS *	extGS
	GL_EXT_geometry_shader4.

Standard_Boolean	extBgra
	GL_EXT_bgra or GL_EXT_texture_format_BGRA8888 on OpenGL ES.

Standard_Boolean	extTexR16
	GL_EXT_texture_norm16 on OpenGL ES; always available on desktop.

Standard_Boolean	extAnis
	GL_EXT_texture_filter_anisotropic.

Standard_Boolean	extPDS
	GL_EXT_packed_depth_stencil.

Standard_Boolean	atiMem
	GL_ATI_meminfo.

Standard_Boolean	nvxMem
	GL_NVX_gpu_memory_info.

Standard_Boolean	oesSampleVariables
	GL_OES_sample_variables.

Standard_Boolean	oesStdDerivatives
	GL_OES_standard_derivatives.

public properties tracking current state
OpenGl_MatrixState< Standard_ShortReal >	ModelWorldState
	state of orientation matrix

OpenGl_MatrixState< Standard_ShortReal >	WorldViewState
	state of orientation matrix

OpenGl_MatrixState< Standard_ShortReal >	ProjectionState
	state of projection matrix

methods to alter or retrieve current state
static Standard_Boolean	CheckIsTransparent (const OpenGl_Aspects *theAspect, const Handle< Graphic3d_PresentationAttributes > &theHighlight, Standard_ShortReal &theAlphaFront, Standard_ShortReal &theAlphaBack)
	Checks if transparency is required for the given aspect and highlight style.

static Standard_Boolean	CheckIsTransparent (const OpenGl_Aspects *theAspect, const Handle< Graphic3d_PresentationAttributes > &theHighlight)
	Checks if transparency is required for the given aspect and highlight style.

const Handle< OpenGl_FrameStats > &	FrameStats () const
	Return structure holding frame statistics.

void	SetFrameStats (const Handle< OpenGl_FrameStats > &theStats)
	Set structure holding frame statistics. This call makes sense only if application defines OpenGl_FrameStats sub-class.

const Standard_Integer *	Viewport () const
	Return cached viewport definition (x, y, width, height).

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

const Standard_Integer *	VirtualViewport () const
	Return virtual viewport definition (x, y, width, height).

Standard_Integer	ReadBuffer ()
	Return active read buffer.

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

Standard_Integer	DrawBuffer (Standard_Integer theIndex=0) const
	Return active draw buffer attached to a render target referred by index (layout location).

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

void	SetDrawBuffers (const Standard_Integer theNb, const Standard_Integer *theDrawBuffers)
	Switch draw buffer, wrapper for ::glDrawBuffers (GLsizei, const GLenum*).

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

bool	IsFrameBufferSRGB () const
	Returns cached GL_FRAMEBUFFER_SRGB state. If TRUE, GLSL program is expected to write linear RGB color. Otherwise, GLSL program might need manually converting result color into sRGB color space.

void	SetFrameBufferSRGB (bool theIsFbo, bool theIsFboSRgb=true)
	Enables/disables GL_FRAMEBUFFER_SRGB flag. This flag can be set to:

const NCollection_Vec4< bool > &	ColorMaskRGBA () const
	Return cached flag indicating writing into color buffer is enabled or disabled (glColorMask).

void	SetColorMaskRGBA (const NCollection_Vec4< bool > &theToWriteColor)
	Enable/disable writing into color buffer (wrapper for glColorMask).

bool	ColorMask () const
	Return cached flag indicating writing into color buffer is enabled or disabled (glColorMask).

bool	SetColorMask (bool theToWriteColor)
	Enable/disable writing into color buffer (wrapper for glColorMask). Alpha component writes will be disabled unconditionally in case of caps->buffersOpaqueAlpha.

bool	AllowSampleAlphaToCoverage () const
	Return TRUE if GL_SAMPLE_ALPHA_TO_COVERAGE usage is allowed.

void	SetAllowSampleAlphaToCoverage (bool theToEnable)
	Allow GL_SAMPLE_ALPHA_TO_COVERAGE usage.

bool	SampleAlphaToCoverage () const
	Return GL_SAMPLE_ALPHA_TO_COVERAGE state.

bool	SetSampleAlphaToCoverage (bool theToEnable)
	Enable/disable GL_SAMPLE_ALPHA_TO_COVERAGE.

Graphic3d_TypeOfBackfacingModel	FaceCulling () const
	Return back face culling state.

void	SetFaceCulling (Graphic3d_TypeOfBackfacingModel theMode)
	Enable or disable back face culling (glEnable (GL_CULL_FACE)).

bool	ToCullBackFaces () const
	Return back face culling state.

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

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.

const Handle< OpenGl_TextureSet > &	ActiveTextures () const

Handle< OpenGl_TextureSet >	BindTextures (const Handle< OpenGl_TextureSet > &theTextures)
	Bind specified texture set to current context taking into account active GLSL program.

Handle< OpenGl_TextureSet >	BindTextures (const Handle< OpenGl_TextureSet > &theTextures, const Handle< OpenGl_ShaderProgram > &theProgram)
	Bind specified texture set to current context, or unbind previous one when NULL specified.

const Handle< OpenGl_ShaderProgram > &	ActiveProgram () const

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

void	SetShadingMaterial (const OpenGl_Aspects *theAspect, const Handle< Graphic3d_PresentationAttributes > &theHighlight)
	Setup current shading material.

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

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

void	SetLineStipple (const uint16_t thePattern)
	Setup stipple line pattern with 1.0f factor; wrapper for glLineStipple().

void	SetLineStipple (const Standard_ShortReal theFactor, const uint16_t thePattern)
	Setup type of line; wrapper for glLineStipple().

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

void	SetPointSize (const Standard_ShortReal theSize)
	Setup point size.

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

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

void	BindDefaultVao ()
	Bind default Vertex Array Object.

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

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!

Standard_Boolean	IsDebugContext () const
	Return debug context initialization state.

void	EnableFeatures () const
	Checks if transparency is required for the given aspect and highlight style.

void	DisableFeatures () const
	Checks if transparency is required for the given aspect and highlight style.

unsigned int	Resolution () const
	Return resolution for rendering text.

Standard_ShortReal	ResolutionRatio () const
	Resolution scale factor (rendered resolution to standard resolution). This scaling factor for parameters like text size to be properly displayed on device (screen / printer).

Standard_ShortReal	RenderScale () const
	Rendering scale factor (rendering viewport height to real window buffer height).

Standard_Boolean	HasRenderScale () const
	Return TRUE if rendering scale factor is not 1.

Standard_ShortReal	RenderScaleInv () const
	Rendering scale factor (inverted value).

Standard_ShortReal	LineWidthScale () const
	Return scale factor for line width.

void	SetResolution (unsigned int theResolution, Standard_ShortReal theRatio, Standard_ShortReal theScale)
	Set resolution ratio. Note that this method rounds @theRatio to nearest integer.

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

Standard_ShortReal	LineFeather () const
	Return line feater width in pixels.

void	SetLineFeather (Standard_ShortReal theValue)
	Set line feater width.

bool	GetBufferSubData (unsigned int theTarget, intptr_t theOffset, intptr_t theSize, void *theData)
	Wrapper over glGetBufferSubData(), implemented as:

const TCollection_AsciiString &	Vendor () const
	Return Graphics Driver's vendor.

void	DumpJson (Standard_OStream &theOStream, Standard_Integer theDepth=-1) const
	Dumps the content of me into the stream.

void	DumpJsonOpenGlState (Standard_OStream &theOStream, Standard_Integer theDepth=-1)
	Dumps the content of openGL state into the stream.

void	SetShadeModel (Graphic3d_TypeOfShadingModel theModel)
	Set GL_SHADE_MODEL value.

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 4.6 version (core12, core13, core14, etc.) as well as several extensions (arbTBO, arbFBO, etc.).

OpenGL context might be initialized in Core Profile. In this case deprecated functionality become unavailable. 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.
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 (core11ffp == 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.

Matrices of OpenGl transformations: model -> world -> view -> projection These matrices might be changed for local transformation, transform persistent using direct access to current matrix of ModelWorldState, WorldViewState and ProjectionState After, these matrices should be applied using ApplyModelWorldMatrix, ApplyWorldViewMatrix, ApplyModelViewMatrix or ApplyProjectionMatrix.

Member Typedef Documentation

◆ OpenGl_ResourcesMap

typedef NCollection_Shared< NCollection_DataMap<TCollection_AsciiString, Handle< OpenGl_Resource > > > OpenGl_Context::OpenGl_ResourcesMap

Constructor & Destructor Documentation

◆ OpenGl_Context()

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

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

◆ ~OpenGl_Context()

virtual OpenGl_Context::~OpenGl_Context ( )

virtual

Destructor.

Member Function Documentation

◆ ActiveProgram()

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

inline

Returns: active GLSL program

◆ ActiveTextures()

const Handle< OpenGl_TextureSet > & OpenGl_Context::ActiveTextures ( ) const

inline

Returns: active textures

◆ AllowSampleAlphaToCoverage()

bool OpenGl_Context::AllowSampleAlphaToCoverage ( ) const

inline

Return TRUE if GL_SAMPLE_ALPHA_TO_COVERAGE usage is allowed.

◆ ApplyModelViewMatrix()

void OpenGl_Context::ApplyModelViewMatrix ( )

Applies combination of matrices stored in ModelWorldState and WorldViewState to OpenGl. In "model -> world -> view -> projection" it performs: model -> world -> view.

◆ ApplyModelWorldMatrix()

void OpenGl_Context::ApplyModelWorldMatrix ( )

Applies matrix into shader manager stored in ModelWorldState to OpenGl. In "model -> world -> view -> projection" it performs: model -> world.

◆ ApplyProjectionMatrix()

void OpenGl_Context::ApplyProjectionMatrix ( )

Applies matrix stored in ProjectionState to OpenGl. In "model -> world -> view -> projection" it performs: view -> projection.

◆ ApplyWorldViewMatrix()

void OpenGl_Context::ApplyWorldViewMatrix ( )

Applies matrix stored in WorldViewState to OpenGl. In "model -> world -> view -> projection" it performs: model -> world -> view, where model -> world is identical matrix.

◆ AvailableMemory()

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.

◆ BindDefaultVao()

void OpenGl_Context::BindDefaultVao ( )

Bind default Vertex Array Object.

◆ BindProgram()

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

◆ BindTextures() [1/2]

Handle< OpenGl_TextureSet > OpenGl_Context::BindTextures ( const Handle< OpenGl_TextureSet > & theTextures )

inline

Bind specified texture set to current context taking into account active GLSL program.

Deprecated:: ("BindTextures() with explicit GLSL program should be used instead")

◆ BindTextures() [2/2]

Handle< OpenGl_TextureSet > OpenGl_Context::BindTextures	(	const Handle< OpenGl_TextureSet > &	theTextures,
		const Handle< OpenGl_ShaderProgram > &	theProgram
	)

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

Parameters

theTextures	[in] texture set to bind
theProgram	[in] program attributes; when not NULL, mock textures will be bound to texture units expected by GLSL program, but undefined by texture set

Returns: previous texture set

◆ Camera()

const Handle< Graphic3d_Camera > & OpenGl_Context::Camera ( ) const

inline

Returns camera object.

◆ ChangeClipping()

OpenGl_Clipping & OpenGl_Context::ChangeClipping ( )

inline

Returns: tool for management of clippings within this context.

◆ CheckExtension() [1/2]

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

Check if theExtName extension is supported by active GL context.

◆ CheckExtension() [2/2]

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

static

Check if theExtName extension is in extensions string.

◆ CheckIsTransparent() [1/2]

static Standard_Boolean OpenGl_Context::CheckIsTransparent	(	const OpenGl_Aspects *	theAspect,
		const Handle< Graphic3d_PresentationAttributes > &	theHighlight
	)

inlinestatic

Checks if transparency is required for the given aspect and highlight style.

◆ CheckIsTransparent() [2/2]

static Standard_Boolean OpenGl_Context::CheckIsTransparent	(	const OpenGl_Aspects *	theAspect,
		const Handle< Graphic3d_PresentationAttributes > &	theHighlight,
		Standard_ShortReal &	theAlphaFront,
		Standard_ShortReal &	theAlphaBack
	)

static

Checks if transparency is required for the given aspect and highlight style.

◆ Clipping()

const OpenGl_Clipping & OpenGl_Context::Clipping ( ) const

inline

Returns: tool for management of clippings within this context.

◆ ColorMask()

bool OpenGl_Context::ColorMask ( ) const

inline

Return cached flag indicating writing into color buffer is enabled or disabled (glColorMask).

◆ ColorMaskRGBA()

const NCollection_Vec4< bool > & OpenGl_Context::ColorMaskRGBA ( ) const

inline

Return cached flag indicating writing into color buffer is enabled or disabled (glColorMask).

◆ DefaultFrameBuffer()

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

inline

Default Frame Buffer Object.

◆ DelayedRelease()

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.

◆ DepthPeelingDepthTexUnit()

Graphic3d_TextureUnit OpenGl_Context::DepthPeelingDepthTexUnit ( ) const

inline

Returns texture unit for occDepthPeelingDepth within enabled Depth Peeling.

◆ DepthPeelingFrontColorTexUnit()

Graphic3d_TextureUnit OpenGl_Context::DepthPeelingFrontColorTexUnit ( ) const

inline

Returns texture unit for occDepthPeelingFrontColor within enabled Depth Peeling.

◆ DiagnosticInformation()

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

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

◆ DisableFeatures()

void OpenGl_Context::DisableFeatures ( ) const

Checks if transparency is required for the given aspect and highlight style.

◆ DrawBuffer()

Standard_Integer OpenGl_Context::DrawBuffer ( Standard_Integer theIndex = 0 ) const

inline

Return active draw buffer attached to a render target referred by index (layout location).

◆ DumpJson()

void OpenGl_Context::DumpJson	(	Standard_OStream &	theOStream,
		Standard_Integer	theDepth = `-1`
	)		const

Dumps the content of me into the stream.

◆ DumpJsonOpenGlState()

void OpenGl_Context::DumpJsonOpenGlState	(	Standard_OStream &	theOStream,
		Standard_Integer	theDepth = `-1`
	)

Dumps the content of openGL state into the stream.

◆ EnableFeatures()

void OpenGl_Context::EnableFeatures ( ) const

Checks if transparency is required for the given aspect and highlight style.

◆ ExcludeMessage()

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_)

◆ FaceCulling()

Graphic3d_TypeOfBackfacingModel OpenGl_Context::FaceCulling ( ) const

inline

Return back face culling state.

◆ FetchState()

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.

◆ FindProc()

template<typename FuncType_t >

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

inline

Auxiliary template to retrieve GL function pointer. Same as FindProcVerbose() but without auxiliary last function name argument.

◆ FindProcVerbose()

template<typename FuncType_t >

Standard_Boolean OpenGl_Context::FindProcVerbose	(	const char *&	theLastFailFuncName,
		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.

Parameters

theLastFailFuncName	[out] set to theFuncName in case of failure, unmodified on success
theFuncName	[in] function name to find
theFuncPtr	[out] retrieved function pointer

Returns: TRUE on success

◆ forcedRelease()

void OpenGl_Context::forcedRelease ( )

Release all resources, including shared ones.

◆ FormatGlEnumHex()

static TCollection_AsciiString OpenGl_Context::FormatGlEnumHex ( int theGlEnum )

static

Format GL constant as hex value 0xABCD.

◆ FormatGlError()

static TCollection_AsciiString OpenGl_Context::FormatGlError ( int theGlError )

static

Return text description of GL error.

◆ FormatPointer()

static TCollection_AsciiString OpenGl_Context::FormatPointer ( const void * thePtr )

static

Format pointer as hex value 0xABCD.

◆ FormatSize()

static TCollection_AsciiString OpenGl_Context::FormatSize ( Standard_Size theSize )

static

Format size value.

◆ FrameStats()

const Handle< OpenGl_FrameStats > & OpenGl_Context::FrameStats ( ) const

inline

Return structure holding frame statistics.

◆ Functions()

const OpenGl_GlFunctions * OpenGl_Context::Functions ( ) const

inline

Access entire map of loaded OpenGL functions.

◆ GetBufferSubData()

bool OpenGl_Context::GetBufferSubData	(	unsigned int	theTarget,
		intptr_t	theOffset,
		intptr_t	theSize,
		void *	theData
	)

Wrapper over glGetBufferSubData(), implemented as:

OpenGL 1.5+ (desktop) via glGetBufferSubData();
OpenGL ES 3.0+ via glMapBufferRange();

WebGL 2.0+ via gl.getBufferSubData().

Parameters

[in]	theTarget	target buffer to map {GLenum}
[in]	theOffset	offset to the beginning of sub-data {GLintptr}
[in]	theSize	number of bytes to read {GLsizeiptr}
[out]	theData	destination pointer to fill

Returns: FALSE if functionality is unavailable

◆ GetDisplay()

Aspect_Display OpenGl_Context::GetDisplay ( ) const

inline

Return display / window device context (EGLDisplay | HDC | Display*).

◆ GetPowerOfTwo()

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

◆ GetResource() [1/2]

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.

◆ GetResource() [2/2]

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.

◆ GraphicsLibrary()

Aspect_GraphicsLibrary OpenGl_Context::GraphicsLibrary ( ) const

inline

Return active graphics library.

◆ HasPBR()

Standard_Boolean OpenGl_Context::HasPBR ( ) const

inline

Returns TRUE if PBR shading model is supported. Basically, feature requires OpenGL 3.0+ / OpenGL ES 3.0+ hardware; more precisely:

Graphics hardware with moderate capabilities for compiling long enough GLSL program.
FBO (e.g. for baking environment).
Multi-texturing with >= 4 units (LUT and IBL textures).
GL_RG32F texture format (arbTexRG + arbTexFloat)
Cubemap texture lookup textureCubeLod()/textureLod() with LOD index within Fragment Shader, which requires GLSL OpenGL 3.0+ / OpenGL ES 3.0+ or OpenGL 2.1 + GL_EXT_gpu_shader4 extension.

◆ HasRayTracing()

Standard_Boolean OpenGl_Context::HasRayTracing ( ) const

inline

Returns: TRUE if ray tracing mode is supported

◆ HasRayTracingAdaptiveSampling()

Standard_Boolean OpenGl_Context::HasRayTracingAdaptiveSampling ( ) const

inline

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

◆ HasRayTracingAdaptiveSamplingAtomic()

Standard_Boolean OpenGl_Context::HasRayTracingAdaptiveSamplingAtomic ( ) const

inline

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

◆ HasRayTracingTextures()

Standard_Boolean OpenGl_Context::HasRayTracingTextures ( ) const

inline

Returns: TRUE if textures in ray tracing mode are supported

◆ HasRenderScale()

Standard_Boolean OpenGl_Context::HasRenderScale ( ) const

inline

Return TRUE if rendering scale factor is not 1.

◆ HasSRGB()

bool OpenGl_Context::HasSRGB ( ) const

inline

Returns TRUE if sRGB rendering is supported.

◆ HasStereoBuffers()

Standard_Boolean OpenGl_Context::HasStereoBuffers ( ) const

inline

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

◆ HasTextureBaseLevel()

Standard_Boolean OpenGl_Context::HasTextureBaseLevel ( ) const

inline

Returns: true if texture parameters GL_TEXTURE_BASE_LEVEL/GL_TEXTURE_MAX_LEVEL are supported.

◆ HasTextureMultisampling()

Standard_Boolean OpenGl_Context::HasTextureMultisampling ( ) const

inline

Returns: true if MSAA textures are supported.

◆ IncludeMessage()

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_)

◆ Init() [1/2]

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

Initialize class from specified surface and rendering context. Method should be called only once. The meaning of parameters is platform-specific.

EGL:

Handle(Aspect_Window) theAspWin;
EGLSurface theEglSurf = eglCreateWindowSurface (theEglDisp, anEglConfig, (EGLNativeWindowType )theAspWin->NativeHandle(), NULL);
EGLDisplay theEglDisp = eglGetDisplay (EGL_DEFAULT_DISPLAY);
EGLContext theEglCtx  = eglCreateContext ((EGLDisplay )theEglDisp, anEglConfig, EGL_NO_CONTEXT, anEglCtxAttribs);
Handle(OpenGl_Context) aGlCtx = new OpenGl_Context();
aGlCtx->Init ((Aspect_Drawable )theEglSurf, (Aspect_Display )theEglDisp,  (Aspect_RenderingContext )theEglCtx);

Windows (Win32):

Handle(WNT_Window) theAspWin;
HWND  theWindow   = (HWND )theAspWin->NativeHandle();
HDC   theDevCtx   = GetDC(theWindow);
HGLRC theGContext = wglCreateContext (theDevCtx);
Handle(OpenGl_Context) aGlCtx = new OpenGl_Context();
aGlCtx->Init ((Aspect_Drawable )theWindow, (Aspect_Display )theDevCtx, (Aspect_RenderingContext )theGContext);

Linux (Xlib):

Handle(Xw_Window) theAspWin;
Window     theXWindow = (Window )theAspWin->NativeHandle();
Display*   theXDisp   = (Display* )theAspWin->DisplayConnection()->GetDisplayAspect();
GLXContext theGlxCtx  = glXCreateContext (theXDisp, aVis.get(), NULL, GL_TRUE);
Handle(OpenGl_Context) aGlCtx = new OpenGl_Context();
aGlCtx->Init ((Aspect_Drawable )theXWindow, (Aspect_Display )theXDisp,  (Aspect_RenderingContext )theGlxCtx);

Parameters

theSurface	[in] surface / window (EGLSurface \| HWND \| GLXDrawable/Window)
theDisplay	[in] display or device context (EGLDisplay \| HDC \| Display*)
theContext	[in] rendering context (EGLContext \| HGLRC \| GLXContext \| EAGLContext* \| NSOpenGLContext*)
theIsCoreProfile	[in] flag indicating that passed GL rendering context has been created with Core Profile

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

◆ Init() [2/2]

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

◆ IsCurrent()

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

◆ IsDebugContext()

Standard_Boolean OpenGl_Context::IsDebugContext ( ) const

inline

Return debug context initialization state.

◆ IsFeedback()

Standard_Boolean OpenGl_Context::IsFeedback ( ) const

Return true if active mode is GL_FEEDBACK (cached state)

◆ IsFrameBufferSRGB()

bool OpenGl_Context::IsFrameBufferSRGB ( ) const

inline

Returns cached GL_FRAMEBUFFER_SRGB state. If TRUE, GLSL program is expected to write linear RGB color. Otherwise, GLSL program might need manually converting result color into sRGB color space.

◆ IsGlGreaterEqual()

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.

◆ IsGlNormalizeEnabled()

Standard_Boolean OpenGl_Context::IsGlNormalizeEnabled ( ) const

inline

Returns: cached state of GL_NORMALIZE.

◆ IsPolygonHatchEnabled()

bool OpenGl_Context::IsPolygonHatchEnabled ( ) const

inline

Returns: cached enabled state of polygon hatching rasterization.

◆ IsRender()

Standard_Boolean OpenGl_Context::IsRender ( ) const

Return true if active mode is GL_RENDER (cached state)

◆ IsValid()

Standard_Boolean OpenGl_Context::IsValid ( ) const

inline

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

◆ IsWindowDeepColor()

bool OpenGl_Context::IsWindowDeepColor ( ) const

inline

Returns TRUE if window/surface buffer has deep color (10bit per component / 30bit RGB) or better precision.

◆ IsWindowSRGB()

bool OpenGl_Context::IsWindowSRGB ( ) const

inline

Returns TRUE if window/surface buffer is sRGB-ready.

When offscreen FBOs are created in sRGB, but window is not sRGB-ready, blitting into window should be done with manual gamma correction.

In desktop OpenGL, window buffer can be considered as sRGB-ready by default, even when application has NOT requested sRGB-ready pixel format, and rendering is managed via GL_FRAMEBUFFER_SRGB state.

In OpenGL ES, sRGB-ready window surface should be explicitly requested on construction, and cannot be disabled/enabled without GL_EXT_sRGB_write_control extension afterwards (GL_FRAMEBUFFER_SRGB can be considered as always tuned ON).

◆ LineFeather()

Standard_ShortReal OpenGl_Context::LineFeather ( ) const

inline

Return line feater width in pixels.

◆ LineWidthScale()

Standard_ShortReal OpenGl_Context::LineWidthScale ( ) const

inline

Return scale factor for line width.

◆ MakeCurrent()

Standard_Boolean OpenGl_Context::MakeCurrent ( )

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

◆ MaxClipPlanes()

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

◆ MaxColorAttachments()

Standard_Integer OpenGl_Context::MaxColorAttachments ( ) const

inline

Returns: value for GL_MAX_COLOR_ATTACHMENTS

◆ MaxCombinedTextureUnits()

Standard_Integer OpenGl_Context::MaxCombinedTextureUnits ( ) const

inline

Returns: value for GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS

◆ MaxDegreeOfAnisotropy()

Standard_Integer OpenGl_Context::MaxDegreeOfAnisotropy ( ) const

inline

Returns: maximum degree of anisotropy texture filter

◆ MaxDrawBuffers()

Standard_Integer OpenGl_Context::MaxDrawBuffers ( ) const

inline

Returns: value for GL_MAX_DRAW_BUFFERS

◆ MaxDumpSizeX()

Standard_Integer OpenGl_Context::MaxDumpSizeX ( ) const

inline

Returns: maximum FBO width for image dump

◆ MaxDumpSizeY()

Standard_Integer OpenGl_Context::MaxDumpSizeY ( ) const

inline

Returns: maximum FBO height for image dump

◆ MaxMsaaSamples()

Standard_Integer OpenGl_Context::MaxMsaaSamples ( ) const

inline

Returns: value for GL_MAX_SAMPLES

◆ MaxTextureSize()

Standard_Integer OpenGl_Context::MaxTextureSize ( ) const

inline

Returns: value for GL_MAX_TEXTURE_SIZE

◆ MaxTextureUnitsFFP()

Standard_Integer OpenGl_Context::MaxTextureUnitsFFP ( ) const

inline

This method returns the multi-texture limit for obsolete fixed-function pipeline. Use MaxCombinedTextureUnits() instead for limits for using programmable pipeline.

Returns: value for GL_MAX_TEXTURE_UNITS

◆ MemoryInfo() [1/2]

TCollection_AsciiString OpenGl_Context::MemoryInfo ( ) const

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

◆ MemoryInfo() [2/2]

void OpenGl_Context::MemoryInfo ( TColStd_IndexedDataMapOfStringString & theDict ) const

This function retrieves information from GL about GPU memory.

◆ Messenger()

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

inline

Returns: messenger instance

◆ PBRDiffIBLMapSHTexUnit()

Graphic3d_TextureUnit OpenGl_Context::PBRDiffIBLMapSHTexUnit ( ) const

inline

Returns texture unit where Diffuse (irradiance) IBL map's spherical harmonics coefficients is expected to be bound, or 0 if PBR is unavailable.

◆ PBREnvLUTTexUnit()

Graphic3d_TextureUnit OpenGl_Context::PBREnvLUTTexUnit ( ) const

inline

Returns texture unit where Environment Lookup Table is expected to be bound, or 0 if PBR is unavailable.

◆ PBRSpecIBLMapTexUnit()

Graphic3d_TextureUnit OpenGl_Context::PBRSpecIBLMapTexUnit ( ) const

inline

Returns texture unit where Specular IBL map is expected to be bound, or 0 if PBR is unavailable.

◆ PolygonHatchStyle()

Standard_Integer OpenGl_Context::PolygonHatchStyle ( ) const

inline

Returns: cached state of polygon hatch type.

◆ PolygonMode()

Standard_Integer OpenGl_Context::PolygonMode ( ) const

inline

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

◆ PolygonOffset()

const Graphic3d_PolygonOffset & OpenGl_Context::PolygonOffset ( ) const

inline

Returns currently applied polygon offset parameters.

◆ PushMessage()

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

◆ ReadBuffer()

Standard_Integer OpenGl_Context::ReadBuffer ( )

inline

Return active read buffer.

◆ ReadGlVersion()

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

static

Read OpenGL version information from active context.

◆ ReleaseDelayed()

void OpenGl_Context::ReleaseDelayed ( )

Clean up the delayed release queue.

◆ ReleaseResource()

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

◆ RenderingContext()

Aspect_RenderingContext OpenGl_Context::RenderingContext ( ) const

inline

Return rendering context (EGLContext | HGLRC | GLXContext | EAGLContext* | NSOpenGLContext*).

◆ RenderScale()

Standard_ShortReal OpenGl_Context::RenderScale ( ) const

inline

Rendering scale factor (rendering viewport height to real window buffer height).

◆ RenderScaleInv()

Standard_ShortReal OpenGl_Context::RenderScaleInv ( ) const

inline

Rendering scale factor (inverted value).

◆ ResetErrors()

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

◆ ResizeViewport()

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

Resize the viewport (alias for glViewport).

Parameters

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

◆ Resolution()

unsigned int OpenGl_Context::Resolution ( ) const

inline

Return resolution for rendering text.

◆ ResolutionRatio()

Standard_ShortReal OpenGl_Context::ResolutionRatio ( ) const

inline

Resolution scale factor (rendered resolution to standard resolution). This scaling factor for parameters like text size to be properly displayed on device (screen / printer).

◆ SampleAlphaToCoverage()

bool OpenGl_Context::SampleAlphaToCoverage ( ) const

inline

Return GL_SAMPLE_ALPHA_TO_COVERAGE state.

◆ SetAllowSampleAlphaToCoverage()

void OpenGl_Context::SetAllowSampleAlphaToCoverage ( bool theToEnable )

inline

Allow GL_SAMPLE_ALPHA_TO_COVERAGE usage.

◆ SetCamera()

void OpenGl_Context::SetCamera ( const Handle< Graphic3d_Camera > & theCamera )

Sets camera object to the context and update matrices.

◆ SetColor4fv()

void OpenGl_Context::SetColor4fv ( const OpenGl_Vec4 & theColor )

Setup current color.

◆ SetColorMask()

bool OpenGl_Context::SetColorMask ( bool theToWriteColor )

Enable/disable writing into color buffer (wrapper for glColorMask). Alpha component writes will be disabled unconditionally in case of caps->buffersOpaqueAlpha.

◆ SetColorMaskRGBA()

void OpenGl_Context::SetColorMaskRGBA ( const NCollection_Vec4< bool > & theToWriteColor )

Enable/disable writing into color buffer (wrapper for glColorMask).

◆ SetCullBackFaces()

void OpenGl_Context::SetCullBackFaces ( bool theToEnable )

inline

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

◆ SetDefaultFrameBuffer()

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!

◆ SetDrawBuffer()

void OpenGl_Context::SetDrawBuffer ( const Standard_Integer theDrawBuffer )

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

◆ SetDrawBuffers()

void OpenGl_Context::SetDrawBuffers	(	const Standard_Integer	theNb,
		const Standard_Integer *	theDrawBuffers
	)

Switch draw buffer, wrapper for ::glDrawBuffers (GLsizei, const GLenum*).

◆ SetFaceCulling()

void OpenGl_Context::SetFaceCulling ( Graphic3d_TypeOfBackfacingModel theMode )

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

◆ SetFrameBufferSRGB()

void OpenGl_Context::SetFrameBufferSRGB	(	bool	theIsFbo,
		bool	theIsFboSRgb = `true`
	)

Enables/disables GL_FRAMEBUFFER_SRGB flag. This flag can be set to:

TRUE when writing into offscreen FBO (always expected to be in sRGB or RGBF formats).
TRUE when writing into sRGB-ready window buffer (might require choosing proper pixel format on window creation).

FALSE if sRGB rendering is not supported or sRGB-not-ready window buffer is used for drawing.

Parameters

[in]	theIsFbo	flag indicating writing into offscreen FBO (always expected sRGB-ready when sRGB FBO is supported) or into window buffer (FALSE, sRGB-readiness might vary).
[in]	theIsFboSRgb	flag indicating off-screen FBO is sRGB-ready

◆ SetFrameStats()

void OpenGl_Context::SetFrameStats ( const Handle< OpenGl_FrameStats > & theStats )

inline

Set structure holding frame statistics. This call makes sense only if application defines OpenGl_FrameStats sub-class.

◆ SetGlNormalizeEnabled()

Standard_Boolean OpenGl_Context::SetGlNormalizeEnabled ( Standard_Boolean isEnabled )

Sets GL_NORMALIZE enabled or disabled.

Returns: old value of the flag

◆ SetLineFeather()

void OpenGl_Context::SetLineFeather ( Standard_ShortReal theValue )

inline

Set line feater width.

◆ SetLineStipple() [1/2]

void OpenGl_Context::SetLineStipple	(	const Standard_ShortReal	theFactor,
		const uint16_t	thePattern
	)

Setup type of line; wrapper for glLineStipple().

◆ SetLineStipple() [2/2]

void OpenGl_Context::SetLineStipple ( const uint16_t thePattern )

inline

Setup stipple line pattern with 1.0f factor; wrapper for glLineStipple().

◆ SetLineWidth()

void OpenGl_Context::SetLineWidth ( const Standard_ShortReal theWidth )

Setup width of line.

◆ SetPointSize()

void OpenGl_Context::SetPointSize ( const Standard_ShortReal theSize )

Setup point size.

◆ SetPointSpriteOrigin()

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

◆ SetPolygonHatchEnabled()

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.

◆ SetPolygonHatchStyle()

Standard_Integer OpenGl_Context::SetPolygonHatchStyle ( const Handle< Graphic3d_HatchStyle > & theStyle )

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

Parameters

theStyle 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.

◆ SetPolygonMode()

Standard_Integer OpenGl_Context::SetPolygonMode ( const Standard_Integer theMode )

Sets polygon rasterization mode (glPolygonMode() function).

Returns: old value of the rasterization mode.

◆ SetPolygonOffset()

void OpenGl_Context::SetPolygonOffset ( const Graphic3d_PolygonOffset & theOffset )

Sets and applies current polygon offset.

◆ SetReadBuffer()

void OpenGl_Context::SetReadBuffer ( const Standard_Integer theReadBuffer )

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

◆ SetReadDrawBuffer()

void OpenGl_Context::SetReadDrawBuffer ( const Standard_Integer theBuffer )

inline

Switch read/draw buffers.

◆ SetResolution()

void OpenGl_Context::SetResolution	(	unsigned int	theResolution,
		Standard_ShortReal	theRatio,
		Standard_ShortReal	theScale
	)

inline

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

◆ SetResolutionRatio()

void OpenGl_Context::SetResolutionRatio ( const Standard_ShortReal theRatio )

inline

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

◆ SetSampleAlphaToCoverage()

bool OpenGl_Context::SetSampleAlphaToCoverage ( bool theToEnable )

Enable/disable GL_SAMPLE_ALPHA_TO_COVERAGE.

◆ SetShadeModel()

void OpenGl_Context::SetShadeModel ( Graphic3d_TypeOfShadingModel theModel )

Set GL_SHADE_MODEL value.

◆ SetShadingMaterial()

void OpenGl_Context::SetShadingMaterial	(	const OpenGl_Aspects *	theAspect,
		const Handle< Graphic3d_PresentationAttributes > &	theHighlight
	)

Setup current shading material.

◆ SetSwapInterval()

Standard_Boolean OpenGl_Context::SetSwapInterval ( const Standard_Integer theInterval )

Setup swap interval (VSync).

◆ SetTextureMatrix()

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

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

Parameters

theParams	[in] texture parameters
theIsTopDown	[in] texture top-down flag

◆ SetTypeOfLine()

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

Setup type of line.

◆ SetWindowSRGB()

void OpenGl_Context::SetWindowSRGB ( bool theIsSRgb )

inline

Overrides if window/surface buffer is sRGB-ready or not (initialized with the context).

◆ ShaderManager()

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

inline

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

◆ ShadowMapTexUnit()

Graphic3d_TextureUnit OpenGl_Context::ShadowMapTexUnit ( ) const

inline

Returns texture unit where shadow map is expected to be bound, or 0 if unavailable.

◆ Share()

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

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

◆ SharedResources()

const OpenGl_ResourcesMap & OpenGl_Context::SharedResources ( ) const

inline

Return map of shared resources.

◆ ShareResource()

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.

◆ SpriteTextureUnit()

Graphic3d_TextureUnit OpenGl_Context::SpriteTextureUnit ( ) const

inline

Return texture unit to be used for sprites (Graphic3d_TextureUnit_PointSprite by default).

◆ SupportedTextureFormats()

const Handle< Image_SupportedFormats > & OpenGl_Context::SupportedTextureFormats ( ) const

inline

Return map of supported texture formats.

◆ SwapBuffers()

void OpenGl_Context::SwapBuffers ( )

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

◆ TextureWrapClamp()

Standard_Integer OpenGl_Context::TextureWrapClamp ( ) const

inline

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

◆ ToCullBackFaces()

bool OpenGl_Context::ToCullBackFaces ( ) const

inline

Return back face culling state.

◆ ToRenderSRGB()

bool OpenGl_Context::ToRenderSRGB ( ) const

inline

Returns TRUE if sRGB rendering is supported and permitted.

◆ ToUseVbo()

bool OpenGl_Context::ToUseVbo ( ) const

inline

Returns true if VBO is supported and permitted.

◆ Vec4FromQuantityColor()

OpenGl_Vec4 OpenGl_Context::Vec4FromQuantityColor ( const OpenGl_Vec4 & theColor ) const

inline

Convert Quantity_ColorRGBA into vec4 with conversion or no conversion into non-linear sRGB basing on ToRenderSRGB() flag.

◆ Vec4LinearFromQuantityColor()

const OpenGl_Vec4 & OpenGl_Context::Vec4LinearFromQuantityColor ( const OpenGl_Vec4 & theColor ) const

inline

Convert Quantity_ColorRGBA into vec4. Quantity_Color is expected to be linear RGB, hence conversion is NOT required.

◆ Vec4sRGBFromQuantityColor()

OpenGl_Vec4 OpenGl_Context::Vec4sRGBFromQuantityColor ( const OpenGl_Vec4 & theColor ) const

inline

Convert Quantity_ColorRGBA (linear RGB) into non-linear sRGB vec4.

◆ Vendor()

const TCollection_AsciiString & OpenGl_Context::Vendor ( ) const

inline

Return Graphics Driver's vendor.

◆ VersionMajor()

Standard_Integer OpenGl_Context::VersionMajor ( ) const

inline

Return cached GL version major number.

◆ VersionMinor()

Standard_Integer OpenGl_Context::VersionMinor ( ) const

inline

Return cached GL version minor number.

◆ Viewport()

const Standard_Integer * OpenGl_Context::Viewport ( ) const

inline

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

◆ VirtualViewport()

const Standard_Integer * OpenGl_Context::VirtualViewport ( ) const

inline

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

◆ Window()

Aspect_Drawable OpenGl_Context::Window ( ) const

inline

Return window handle currently bound to this OpenGL context (EGLSurface | HWND | GLXDrawable).

◆ WindowBufferBits()

void OpenGl_Context::WindowBufferBits	(	Graphic3d_Vec4i &	theColorBits,
		Graphic3d_Vec2i &	theDepthStencilBits
	)		const

Fetches information about window buffer pixel format.

Field Documentation

◆ arbClipControl

Standard_Boolean OpenGl_Context::arbClipControl

GL_ARB_clip_control, in core since 4.5.

◆ arbDbg

OpenGl_ArbDbg* OpenGl_Context::arbDbg

GL_ARB_debug_output (on desktop OpenGL - since 4.3 or as extension GL_ARB_debug_output; on OpenGL ES - since 3.2 or as extension GL_KHR_debug)

◆ arbDepthClamp

Standard_Boolean OpenGl_Context::arbDepthClamp

GL_ARB_depth_clamp (on desktop OpenGL - since 3.2 or as extensions GL_ARB_depth_clamp,NV_depth_clamp; unavailable on OpenGL ES)

◆ arbDrawBuffers

Standard_Boolean OpenGl_Context::arbDrawBuffers

GL_ARB_draw_buffers.

◆ arbFBO

OpenGl_ArbFBO* OpenGl_Context::arbFBO

GL_ARB_framebuffer_object.

◆ arbFBOBlit

OpenGl_ArbFBOBlit* OpenGl_Context::arbFBOBlit

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

◆ arbIns

OpenGl_ArbIns* OpenGl_Context::arbIns

GL_ARB_draw_instanced (on desktop OpenGL - since 3.1 or as extension GL_ARB_draw_instanced; on OpenGL ES - since 3.0 or as extension GL_ANGLE_instanced_arrays to WebGL 1.0)

◆ arbNPTW

Standard_Boolean OpenGl_Context::arbNPTW

GL_ARB_texture_non_power_of_two.

◆ arbSamplerObject

OpenGl_ArbSamplerObject* OpenGl_Context::arbSamplerObject

GL_ARB_sampler_objects (on desktop OpenGL - since 3.3 or as extension GL_ARB_sampler_objects; on OpenGL ES - since 3.0)

◆ arbSampleShading

Standard_Boolean OpenGl_Context::arbSampleShading

GL_ARB_sample_shading.

◆ arbTBO

OpenGl_ArbTBO* OpenGl_Context::arbTBO

GL_ARB_texture_buffer_object (on desktop OpenGL - since 3.1 or as extension GL_ARB_texture_buffer_object; on OpenGL ES - since 3.2)

◆ arbTboRGB32

Standard_Boolean OpenGl_Context::arbTboRGB32

GL_ARB_texture_buffer_object_rgb32 (3-component TBO), in core since 4.0 (on OpenGL ES - since 3.2)

◆ arbTexBindless

OpenGl_ArbTexBindless* OpenGl_Context::arbTexBindless

GL_ARB_bindless_texture.

◆ arbTexFloat

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);.

See also: hasTexFloatLinear for linear filtering support

◆ arbTexRG

Standard_Boolean OpenGl_Context::arbTexRG

GL_ARB_texture_rg.

◆ atiMem

Standard_Boolean OpenGl_Context::atiMem

GL_ATI_meminfo.

◆ caps

Handle< OpenGl_Caps > OpenGl_Context::caps

context options

◆ core11ffp

OpenGl_GlCore11* OpenGl_Context::core11ffp

OpenGL 1.1 core functionality.

◆ core11fwd

OpenGl_GlCore11Fwd* OpenGl_Context::core11fwd

OpenGL 1.1 without deprecated entry points.

◆ core15

OpenGl_GlCore15* OpenGl_Context::core15

OpenGL 1.5 without deprecated entry points.

◆ core15fwd

OpenGl_GlCore15* OpenGl_Context::core15fwd

obsolete entry left for code portability; core15 should be used instead

◆ core20

OpenGl_GlCore20* OpenGl_Context::core20

OpenGL 2.0 without deprecated entry points.

◆ core20fwd

OpenGl_GlCore20* OpenGl_Context::core20fwd

obsolete entry left for code portability; core20 should be used instead

◆ core30

OpenGl_GlCore30* OpenGl_Context::core30

OpenGL 3.0 without deprecated entry points.

◆ core32

OpenGl_GlCore32* OpenGl_Context::core32

OpenGL 3.2 core profile.

◆ core33

OpenGl_GlCore33* OpenGl_Context::core33

OpenGL 3.3 core profile.

◆ core41

OpenGl_GlCore41* OpenGl_Context::core41

OpenGL 4.1 core profile.

◆ core42

OpenGl_GlCore42* OpenGl_Context::core42

OpenGL 4.2 core profile.

◆ core43

OpenGl_GlCore43* OpenGl_Context::core43

OpenGL 4.3 core profile.

◆ core44

OpenGl_GlCore44* OpenGl_Context::core44

OpenGL 4.4 core profile.

◆ core45

OpenGl_GlCore45* OpenGl_Context::core45

OpenGL 4.5 core profile.

◆ core46

OpenGl_GlCore46* OpenGl_Context::core46

OpenGL 4.6 core profile.

◆ extAnis

Standard_Boolean OpenGl_Context::extAnis

GL_EXT_texture_filter_anisotropic.

◆ extBgra

Standard_Boolean OpenGl_Context::extBgra

GL_EXT_bgra or GL_EXT_texture_format_BGRA8888 on OpenGL ES.

◆ extDrawBuffers

Standard_Boolean OpenGl_Context::extDrawBuffers

GL_EXT_draw_buffers.

◆ extFragDepth

Standard_Boolean OpenGl_Context::extFragDepth

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

◆ extGS

OpenGl_ExtGS* OpenGl_Context::extGS

GL_EXT_geometry_shader4.

◆ extPDS

Standard_Boolean OpenGl_Context::extPDS

GL_EXT_packed_depth_stencil.

◆ extTexR16

Standard_Boolean OpenGl_Context::extTexR16

GL_EXT_texture_norm16 on OpenGL ES; always available on desktop.

◆ hasDrawBuffers

OpenGl_FeatureFlag OpenGl_Context::hasDrawBuffers

Complex flag indicating support of multiple draw buffers (desktop OpenGL 2.0, OpenGL ES 3.0, GL_ARB_draw_buffers, GL_EXT_draw_buffers)

◆ hasFboRenderMipmap

Standard_Boolean OpenGl_Context::hasFboRenderMipmap

FBO render target could be non-zero mipmap level of texture.

◆ hasFboSRGB

Standard_Boolean OpenGl_Context::hasFboSRGB

sRGB FBO render targets (desktop OpenGL 2.1, OpenGL ES 3.0)

◆ hasFlatShading

OpenGl_FeatureFlag OpenGl_Context::hasFlatShading

Complex flag indicating support of Flat shading (Graphic3d_TypeOfShadingModel_Phong) (always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_standard_derivatives)

◆ hasFloatBuffer

OpenGl_FeatureFlag OpenGl_Context::hasFloatBuffer

Complex flag indicating support of float color buffer format (desktop OpenGL 3.0, GL_ARB_color_buffer_float, GL_EXT_color_buffer_float)

◆ hasGeometryStage

OpenGl_FeatureFlag OpenGl_Context::hasGeometryStage

Complex flag indicating support of Geometry shader (desktop OpenGL 3.2, OpenGL ES 3.2, GL_EXT_geometry_shader)

◆ hasGetBufferData

Standard_Boolean OpenGl_Context::hasGetBufferData

flag indicating if GetBufferSubData() is supported

◆ hasGlslBitwiseOps

OpenGl_FeatureFlag OpenGl_Context::hasGlslBitwiseOps

GLSL supports bitwise operations; OpenGL 3.0 / OpenGL ES 3.0 (GLSL 130 / GLSL ES 300) or OpenGL 2.1 + GL_EXT_gpu_shader4.

◆ hasHalfFloatBuffer

OpenGl_FeatureFlag OpenGl_Context::hasHalfFloatBuffer

Complex flag indicating support of half-float color buffer format (desktop OpenGL 3.0, GL_ARB_color_buffer_float, GL_EXT_color_buffer_half_float)

◆ hasHighp

Standard_Boolean OpenGl_Context::hasHighp

highp in GLSL ES fragment shader is supported

◆ hasPackRowLength

Standard_Boolean OpenGl_Context::hasPackRowLength

supporting of GL_PACK_ROW_LENGTH parameters (any desktop OpenGL; OpenGL ES 3.0)

◆ hasSampleVariables

OpenGl_FeatureFlag OpenGl_Context::hasSampleVariables

Complex flag indicating support of MSAA variables in GLSL shader (desktop OpenGL 4.0, GL_ARB_sample_shading)

◆ hasSRGBControl

Standard_Boolean OpenGl_Context::hasSRGBControl

sRGB write control (any desktop OpenGL, OpenGL ES + GL_EXT_sRGB_write_control extension)

◆ hasTexFloatLinear

Standard_Boolean OpenGl_Context::hasTexFloatLinear

texture-filterable state for 32-bit floating texture formats (always on desktop, GL_OES_texture_float_linear within OpenGL ES)

◆ hasTexRGBA8

Standard_Boolean OpenGl_Context::hasTexRGBA8

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

◆ hasTexSRGB

Standard_Boolean OpenGl_Context::hasTexSRGB

sRGB texture formats (desktop OpenGL 2.1, OpenGL ES 3.0 or OpenGL ES 2.0 + GL_EXT_sRGB)

◆ hasUintIndex

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)

◆ hasUnpackRowLength

Standard_Boolean OpenGl_Context::hasUnpackRowLength

supporting of GL_UNPACK_ROW_LENGTH parameters (any desktop OpenGL; OpenGL ES 3.0)

◆ ModelWorldState

OpenGl_MatrixState<Standard_ShortReal> OpenGl_Context::ModelWorldState

state of orientation matrix

◆ nvxMem

Standard_Boolean OpenGl_Context::nvxMem

GL_NVX_gpu_memory_info.

◆ oesSampleVariables

Standard_Boolean OpenGl_Context::oesSampleVariables

GL_OES_sample_variables.

◆ oesStdDerivatives

Standard_Boolean OpenGl_Context::oesStdDerivatives

GL_OES_standard_derivatives.

◆ ProjectionState

OpenGl_MatrixState<Standard_ShortReal> OpenGl_Context::ProjectionState

state of projection matrix

◆ WorldViewState

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

Public Types

Public Member Functions

Static Public Member Functions

Data Fields

public properties tracking current state

methods to alter or retrieve current state

Detailed Description

Member Typedef Documentation

◆ OpenGl_ResourcesMap

Constructor & Destructor Documentation

◆ OpenGl_Context()

◆ ~OpenGl_Context()

Member Function Documentation

◆ ActiveProgram()

◆ ActiveTextures()

◆ AllowSampleAlphaToCoverage()

◆ ApplyModelViewMatrix()

◆ ApplyModelWorldMatrix()

◆ ApplyProjectionMatrix()

◆ ApplyWorldViewMatrix()

◆ AvailableMemory()

◆ BindDefaultVao()

◆ BindProgram()

◆ BindTextures() [1/2]

◆ BindTextures() [2/2]

◆ Camera()

◆ ChangeClipping()

◆ CheckExtension() [1/2]

◆ CheckExtension() [2/2]

◆ CheckIsTransparent() [1/2]

◆ CheckIsTransparent() [2/2]

◆ Clipping()

◆ ColorMask()

◆ ColorMaskRGBA()

◆ DefaultFrameBuffer()

◆ DelayedRelease()

◆ DepthPeelingDepthTexUnit()

◆ DepthPeelingFrontColorTexUnit()

◆ DiagnosticInformation()

◆ DisableFeatures()

◆ DrawBuffer()

◆ DumpJson()

◆ DumpJsonOpenGlState()

◆ EnableFeatures()

◆ ExcludeMessage()

◆ FaceCulling()

◆ FetchState()

◆ FindProc()

◆ FindProcVerbose()

◆ forcedRelease()

◆ FormatGlEnumHex()

◆ FormatGlError()

◆ FormatPointer()

◆ FormatSize()

◆ FrameStats()

◆ Functions()

◆ GetBufferSubData()

◆ GetDisplay()

◆ GetPowerOfTwo()

◆ GetResource() [1/2]

◆ GetResource() [2/2]

◆ GraphicsLibrary()

◆ HasPBR()

◆ HasRayTracing()

◆ HasRayTracingAdaptiveSampling()

◆ HasRayTracingAdaptiveSamplingAtomic()

◆ HasRayTracingTextures()

◆ HasRenderScale()

◆ HasSRGB()

◆ HasStereoBuffers()

◆ HasTextureBaseLevel()

◆ HasTextureMultisampling()

◆ IncludeMessage()

◆ Init() [1/2]

◆ Init() [2/2]

◆ IsCurrent()

◆ IsDebugContext()

◆ IsFeedback()

◆ IsFrameBufferSRGB()

◆ IsGlGreaterEqual()