1 // Created on: 2012-01-26
2 // Created by: Kirill GAVRILOV
3 // Copyright (c) 2012-2014 OPEN CASCADE SAS
4 //
5 // This file is part of Open CASCADE Technology software library.
6 //
7 // This library is free software; you can redistribute it and/or modify it under
8 // the terms of the GNU Lesser General Public License version 2.1 as published
9 // by the Free Software Foundation, with special exception defined in the file
10 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
11 // distribution for complete text of the license and disclaimer of any warranty.
12 //
13 // Alternatively, this file may be used under the terms of Open CASCADE
14 // commercial license or contractual agreement.
15 
16 #ifndef OpenGl_Context_HeaderFile
17 #define OpenGl_Context_HeaderFile
18 
19 #include <Aspect_Handle.hxx>
20 #include <Aspect_HatchStyle.hxx>
21 #include <Aspect_Drawable.hxx>
22 #include <Aspect_Display.hxx>
23 #include <Aspect_RenderingContext.hxx>
24 #include <Aspect_TypeOfLine.hxx>
25 #include <NCollection_DataMap.hxx>
26 #include <Graphic3d_DiagnosticInfo.hxx>
27 #include <Graphic3d_TextureUnit.hxx>
28 #include <NCollection_Map.hxx>
29 #include <NCollection_Handle.hxx>
30 #include <NCollection_List.hxx>
31 #include <NCollection_SparseArray.hxx>
32 #include <Message.hxx>
33 #include <OpenGl_Caps.hxx>
34 #include <OpenGl_LineAttributes.hxx>
35 #include <OpenGl_Material.hxx>
36 #include <OpenGl_MatrixState.hxx>
37 #include <OpenGl_Vec.hxx>
38 #include <OpenGl_Resource.hxx>
39 #include <OpenGl_TextureSet.hxx>
40 #include <Standard_Transient.hxx>
41 #include <TColStd_IndexedDataMapOfStringString.hxx>
42 #include <TColStd_PackedMapOfInteger.hxx>
43 #include <OpenGl_Clipping.hxx>
44 #include <OpenGl_GlCore11.hxx>
45 
46 #include <NCollection_Shared.hxx>
47 
48 //! Forward declarations
49 #if defined(__APPLE__)
50   #import <TargetConditionals.h>
51   #if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
52     #ifdef __OBJC__
53       @class EAGLContext;
54     #else
55       struct EAGLContext;
56     #endif
57   #else
58     #ifdef __OBJC__
59       @class NSOpenGLContext;
60     #else
61       struct NSOpenGLContext;
62     #endif
63   #endif
64 #endif
65 
66 struct OpenGl_GlFunctions;
67 struct OpenGl_ArbTBO;
68 struct OpenGl_ArbIns;
69 struct OpenGl_ArbDbg;
70 struct OpenGl_ArbFBO;
71 struct OpenGl_ArbFBOBlit;
72 struct OpenGl_ArbSamplerObject;
73 struct OpenGl_ArbTexBindless;
74 struct OpenGl_ExtGS;
75 
76 struct OpenGl_GlCore12;
77 struct OpenGl_GlCore13;
78 struct OpenGl_GlCore14;
79 struct OpenGl_GlCore15;
80 struct OpenGl_GlCore20;
81 struct OpenGl_GlCore21;
82 struct OpenGl_GlCore30;
83 struct OpenGl_GlCore31;
84 struct OpenGl_GlCore32;
85 struct OpenGl_GlCore33;
86 struct OpenGl_GlCore40;
87 struct OpenGl_GlCore41;
88 struct OpenGl_GlCore42;
89 struct OpenGl_GlCore43;
90 struct OpenGl_GlCore44;
91 struct OpenGl_GlCore45;
92 struct OpenGl_GlCore46;
93 
94 class Graphic3d_Camera;
95 class Graphic3d_PresentationAttributes;
96 class OpenGl_Aspects;
97 class OpenGl_FrameBuffer;
98 class OpenGl_Sampler;
99 class OpenGl_ShaderProgram;
100 class OpenGl_ShaderManager;
101 class OpenGl_FrameStats;
102 
103 enum OpenGl_FeatureFlag
104 {
105   OpenGl_FeatureNotAvailable = 0, //!< Feature is not supported by OpenGl implementation.
106   OpenGl_FeatureInExtensions = 1, //!< Feature is supported as extension.
107   OpenGl_FeatureInCore       = 2  //!< Feature is supported as part of core profile.
108 };
109 
110 DEFINE_STANDARD_HANDLE(OpenGl_Context, Standard_Transient)
111 
112 //! This class generalize access to the GL context and available extensions.
113 //!
114 //! Functions related to specific OpenGL version or extension are grouped into structures which can be accessed as fields of this class.
115 //! The most simple way to check that required functionality is available - is NULL check for the group:
116 //! @code
117 //!   if (myContext->core20 != NULL)
118 //!   {
119 //!     myGlProgram = myContext->core20->glCreateProgram();
120 //!     .. do more stuff ..
121 //!   }
122 //!   else
123 //!   {
124 //!     .. compatibility with outdated configurations ..
125 //!   }
126 //! @endcode
127 //!
128 //! Current implementation provide access to OpenGL core functionality up to 4.6 version (core12, core13, core14, etc.)
129 //! as well as several extensions (arbTBO, arbFBO, etc.).
130 //!
131 //! OpenGL context might be initialized in Core Profile. In this case deprecated functionality become unavailable.
132 //! To select which core** function set should be used in specific case:
133 //!  - Determine the minimal OpenGL version required for implemented functionality and use it to access all functions.
134 //!    For example, if algorithm requires OpenGL 2.1+, it is better to write core20fwd->glEnable() rather than core11fwd->glEnable() for uniformity.
135 //!  - Validate minimal requirements at initialization/creation time and omit checks within code where algorithm should be already initialized.
136 //!    Properly escape code incompatible with Core Profile. The simplest way to check Core Profile is "if (core11ffp == NULL)".
137 //!
138 //! Simplified extensions classification:
139 //!  - prefixed with NV, AMD, ATI are vendor-specific (however may be provided by other vendors in some cases);
140 //!  - prefixed with EXT are accepted by 2+ vendors;
141 //!  - prefixed with ARB are accepted by Architecture Review Board and are candidates
142 //!    for inclusion into GL core functionality.
143 //! Some functionality can be represented in several extensions simultaneously.
144 //! In this case developer should be careful because different specification may differ
145 //! in aspects (like enumeration values and error-handling).
146 //!
147 //! Notice that some systems provide mechanisms to simultaneously incorporate with GL contexts with different capabilities.
148 //! For this reason OpenGl_Context should be initialized and used for each GL context independently.
149 //!
150 //! Matrices of OpenGl transformations:
151 //! model -> world -> view -> projection
152 //! These matrices might be changed for local transformation, transform persistent using direct access to
153 //! current matrix of ModelWorldState, WorldViewState and ProjectionState
154 //! After, these matrices should be applied using ApplyModelWorldMatrix, ApplyWorldViewMatrix,
155 //! ApplyModelViewMatrix or ApplyProjectionMatrix.
156 class OpenGl_Context : public Standard_Transient
157 {
158   DEFINE_STANDARD_RTTIEXT(OpenGl_Context, Standard_Transient)
159   friend class OpenGl_Window;
160   friend struct OpenGl_GlFunctions;
161 public:
162 
163   typedef NCollection_Shared< NCollection_DataMap<TCollection_AsciiString, Handle(OpenGl_Resource)> > OpenGl_ResourcesMap;
164 
165   //! Function for getting power of to number larger or equal to input number.
166   //! @param theNumber    number to 'power of two'
167   //! @param theThreshold upper threshold
168   //! @return power of two number
GetPowerOfTwo(const Standard_Integer theNumber,const Standard_Integer theThreshold)169   inline static Standard_Integer GetPowerOfTwo (const Standard_Integer theNumber,
170                                                 const Standard_Integer theThreshold)
171   {
172     for (Standard_Integer p2 = 2; p2 <= theThreshold; p2 <<= 1)
173     {
174       if (theNumber <= p2)
175       {
176         return p2;
177       }
178     }
179     return theThreshold;
180   }
181 
182   //! Format GL constant as hex value 0xABCD.
183   Standard_EXPORT static TCollection_AsciiString FormatGlEnumHex (int theGlEnum);
184 
185   //! Format pointer as hex value 0xABCD.
186   Standard_EXPORT static TCollection_AsciiString FormatPointer (const void* thePtr);
187 
188   //! Format size value.
189   Standard_EXPORT static TCollection_AsciiString FormatSize (Standard_Size theSize);
190 
191   //! Return text description of GL error.
192   Standard_EXPORT static TCollection_AsciiString FormatGlError (int theGlError);
193 
194 public:
195 
196   //! Empty constructor. You should call Init() to perform initialization with bound GL context.
197   Standard_EXPORT OpenGl_Context (const Handle(OpenGl_Caps)& theCaps = NULL);
198 
199   //! Destructor.
200   Standard_EXPORT virtual ~OpenGl_Context();
201 
202   //! Release all resources, including shared ones
203   Standard_EXPORT void forcedRelease();
204 
205   //! Share GL context resources.
206   //! theShareCtx - handle to context to retrieve handles to shared resources.
207   Standard_EXPORT void Share (const Handle(OpenGl_Context)& theShareCtx);
208 
209   //! Initialize class from currently bound OpenGL context. Method should be called only once.
210   //! @return false if no GL context is bound to the current thread
211   Standard_EXPORT Standard_Boolean Init (const Standard_Boolean theIsCoreProfile = Standard_False);
212 
213   //! @return true if this context is valid (has been initialized)
IsValid() const214   inline Standard_Boolean IsValid() const
215   {
216     return myIsInitialized;
217   }
218 
219   //! Initialize class from specified surface and rendering context. Method should be called only once.
220   //! The meaning of parameters is platform-specific.
221   //!
222   //! EGL:
223   //! @code
224   //!   Handle(Aspect_Window) theAspWin;
225   //!   EGLSurface theEglSurf = eglCreateWindowSurface (theEglDisp, anEglConfig, (EGLNativeWindowType )theAspWin->NativeHandle(), NULL);
226   //!   EGLDisplay theEglDisp = eglGetDisplay (EGL_DEFAULT_DISPLAY);
227   //!   EGLContext theEglCtx  = eglCreateContext ((EGLDisplay )theEglDisp, anEglConfig, EGL_NO_CONTEXT, anEglCtxAttribs);
228   //!   Handle(OpenGl_Context) aGlCtx = new OpenGl_Context();
229   //!   aGlCtx->Init ((Aspect_Drawable )theEglSurf, (Aspect_Display )theEglDisp,  (Aspect_RenderingContext )theEglCtx);
230   //! @endcode
231   //!
232   //! Windows (Win32):
233   //! @code
234   //!   Handle(WNT_Window) theAspWin;
235   //!   HWND  theWindow   = (HWND )theAspWin->NativeHandle();
236   //!   HDC   theDevCtx   = GetDC(theWindow);
237   //!   HGLRC theGContext = wglCreateContext (theDevCtx);
238   //!   Handle(OpenGl_Context) aGlCtx = new OpenGl_Context();
239   //!   aGlCtx->Init ((Aspect_Drawable )theWindow, (Aspect_Display )theDevCtx, (Aspect_RenderingContext )theGContext);
240   //! @endcode
241   //!
242   //! Linux (Xlib):
243   //! @code
244   //!   Handle(Xw_Window) theAspWin;
245   //!   Window     theXWindow = (Window )theAspWin->NativeHandle();
246   //!   Display*   theXDisp   = (Display* )theAspWin->DisplayConnection()->GetDisplayAspect();
247   //!   GLXContext theGlxCtx  = glXCreateContext (theXDisp, aVis.get(), NULL, GL_TRUE);
248   //!   Handle(OpenGl_Context) aGlCtx = new OpenGl_Context();
249   //!   aGlCtx->Init ((Aspect_Drawable )theXWindow, (Aspect_Display )theXDisp,  (Aspect_RenderingContext )theGlxCtx);
250   //! @endcode
251   //!
252   //! @param theSurface [in] surface / window          (EGLSurface | HWND  | GLXDrawable/Window)
253   //! @param theDisplay [in] display or device context (EGLDisplay | HDC   | Display*)
254   //! @param theContext [in] rendering context         (EGLContext | HGLRC | GLXContext | EAGLContext* | NSOpenGLContext*)
255   //! @param theIsCoreProfile [in] flag indicating that passed GL rendering context has been created with Core Profile
256   //! @return false if OpenGL context can not be bound to specified surface
257   Standard_EXPORT Standard_Boolean Init (const Aspect_Drawable         theSurface,
258                                          const Aspect_Display          theDisplay,
259                                          const Aspect_RenderingContext theContext,
260                                          const Standard_Boolean        theIsCoreProfile = Standard_False);
261 
262   //! Return window handle currently bound to this OpenGL context (EGLSurface | HWND | GLXDrawable).
Window() const263   Aspect_Drawable Window() const { return myWindow; }
264 
265   //! Return display / window device context (EGLDisplay | HDC | Display*).
GetDisplay() const266   Aspect_Display GetDisplay() const { return myDisplay; }
267 
268   //! Return rendering context (EGLContext | HGLRC | GLXContext | EAGLContext* | NSOpenGLContext*).
RenderingContext() const269   Aspect_RenderingContext RenderingContext() const { return myGContext; }
270 
271 #if defined(__APPLE__) && !defined(HAVE_XLIB)
272   #if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
273 
274   //! Initialize class from specified OpenGL ES context (EAGLContext). Method should be called only once.
Init(EAGLContext * theGContext,const Standard_Boolean theIsCoreProfile=Standard_False)275   Standard_Boolean Init (EAGLContext*           theGContext,
276                          const Standard_Boolean theIsCoreProfile = Standard_False)
277   {
278     return Init ((Aspect_Drawable )0, (Aspect_Display )0, (Aspect_RenderingContext )theGContext, theIsCoreProfile);
279   }
280   #else
281   //! Initialize class from specified OpenGL context (NSOpenGLContext). Method should be called only once.
Init(NSOpenGLContext * theGContext,const Standard_Boolean theIsCoreProfile=Standard_False)282   Standard_Boolean Init (NSOpenGLContext*       theGContext,
283                          const Standard_Boolean theIsCoreProfile = Standard_False)
284   {
285     return Init ((Aspect_Drawable )0, (Aspect_Display )0, (Aspect_RenderingContext )theGContext, theIsCoreProfile);
286   }
287   #endif
288 #endif
289 
290   //! Read OpenGL version information from active context.
291   Standard_EXPORT static void ReadGlVersion (Standard_Integer& theGlVerMajor,
292                                              Standard_Integer& theGlVerMinor);
293 
294   //! Check if theExtName extension is supported by active GL context.
295   Standard_EXPORT Standard_Boolean CheckExtension (const char* theExtName) const;
296 
297   //! Check if theExtName extension is in extensions string.
298   Standard_EXPORT static Standard_Boolean CheckExtension (const char* theExtString,
299                                                           const char* theExtName);
300 
301   //! Auxiliary template to retrieve GL function pointer.
302   //! Pointer to function retrieved from library is statically casted
303   //! to requested type - there no way to check real signature of exported function.
304   //! The context should be bound before call.
305   //! @param theLastFailFuncName [out] set to theFuncName in case of failure, unmodified on success
306   //! @param theFuncName [in] function name to find
307   //! @param theFuncPtr [out] retrieved function pointer
308   //! @return TRUE on success
309   template <typename FuncType_t>
FindProcVerbose(const char * & theLastFailFuncName,const char * theFuncName,FuncType_t & theFuncPtr)310   Standard_Boolean FindProcVerbose (const char*& theLastFailFuncName,
311                                     const char* theFuncName,
312                                     FuncType_t& theFuncPtr)
313   {
314     theFuncPtr = (FuncType_t )findProc (theFuncName);
315     if (theFuncPtr == NULL)
316     {
317       theLastFailFuncName = theFuncName;
318       return Standard_False;
319     }
320     return Standard_True;
321   }
322 
323   //! Auxiliary template to retrieve GL function pointer.
324   //! Same as FindProcVerbose() but without auxiliary last function name argument.
325   template <typename FuncType_t>
FindProc(const char * theFuncName,FuncType_t & theFuncPtr)326   Standard_Boolean FindProc (const char* theFuncName,
327                              FuncType_t& theFuncPtr)
328   {
329     theFuncPtr = (FuncType_t )findProc (theFuncName);
330     return (theFuncPtr != NULL);
331   }
332 
333   //! @return true if detected GL version is greater or equal to requested one.
IsGlGreaterEqual(const Standard_Integer theVerMajor,const Standard_Integer theVerMinor) const334   inline Standard_Boolean IsGlGreaterEqual (const Standard_Integer theVerMajor,
335                                             const Standard_Integer theVerMinor) const
336   {
337     return (myGlVerMajor >  theVerMajor)
338         || (myGlVerMajor == theVerMajor && myGlVerMinor >= theVerMinor);
339   }
340 
341   //! Return cached GL version major number.
VersionMajor() const342   Standard_Integer VersionMajor() const { return myGlVerMajor; }
343 
344   //! Return cached GL version minor number.
VersionMinor() const345   Standard_Integer VersionMinor() const { return myGlVerMinor; }
346 
347   //! Access entire map of loaded OpenGL functions.
Functions() const348   const OpenGl_GlFunctions* Functions() const { return myFuncs.operator->(); }
349 
350   //! Clean up errors stack for this GL context (glGetError() in loop).
351   //! @return true if some error has been cleared
352   Standard_EXPORT bool ResetErrors (const bool theToPrintErrors = false);
353 
354   //! This method uses system-dependent API to retrieve information
355   //! about GL context bound to the current thread.
356   //! @return true if current thread is bound to this GL context
357   Standard_EXPORT Standard_Boolean IsCurrent() const;
358 
359   //! Activates current context.
360   //! Class should be initialized with appropriate info.
361   Standard_EXPORT Standard_Boolean MakeCurrent();
362 
363   //! Swap front/back buffers for this GL context (should be activated before!).
364   Standard_EXPORT void SwapBuffers();
365 
366   //! Setup swap interval (VSync).
367   Standard_EXPORT Standard_Boolean SetSwapInterval (const Standard_Integer theInterval);
368 
369   //! Return true if active mode is GL_RENDER (cached state)
IsRender() const370   Standard_Boolean IsRender() const
371   {
372   #if !defined(GL_ES_VERSION_2_0)
373     return myRenderMode == GL_RENDER;
374   #else
375     return Standard_True;
376   #endif
377   }
378 
379   //! Return true if active mode is GL_FEEDBACK (cached state)
IsFeedback() const380   Standard_Boolean IsFeedback() const
381   {
382   #if !defined(GL_ES_VERSION_2_0)
383     return myRenderMode == GL_FEEDBACK;
384   #else
385     return Standard_False;
386   #endif
387   }
388 
389   //! This function retrieves information from GL about free GPU memory that is:
390   //!  - OS-dependent. On some OS it is per-process and on others - for entire system.
391   //!  - Vendor-dependent. Currently available only on NVIDIA and AMD/ATi drivers only.
392   //!  - Numbers meaning may vary.
393   //! You should use this info only for diagnostics purposes.
394   //! @return free GPU dedicated memory in bytes.
395   Standard_EXPORT Standard_Size AvailableMemory() const;
396 
397   //! This function retrieves information from GL about GPU memory
398   //! and contains more vendor-specific values than AvailableMemory().
399   Standard_EXPORT TCollection_AsciiString MemoryInfo() const;
400 
401   //! This function retrieves information from GL about GPU memory.
402   Standard_EXPORT void MemoryInfo (TColStd_IndexedDataMapOfStringString& theDict) const;
403 
404   //! Fill in the dictionary with OpenGL info.
405   //! Should be called with bound context.
406   Standard_EXPORT void DiagnosticInformation (TColStd_IndexedDataMapOfStringString& theDict,
407                                               Graphic3d_DiagnosticInfo theFlags) const;
408 
409   //! Access shared resource by its name.
410   //! @param  theKey - unique identifier;
411   //! @return handle to shared resource or NULL.
412   Standard_EXPORT const Handle(OpenGl_Resource)& GetResource (const TCollection_AsciiString& theKey) const;
413 
414   //! Access shared resource by its name.
415   //! @param  theKey   - unique identifier;
416   //! @param  theValue - handle to fill;
417   //! @return true if resource was shared.
418   template<typename TheHandleType>
GetResource(const TCollection_AsciiString & theKey,TheHandleType & theValue) const419   Standard_Boolean GetResource (const TCollection_AsciiString& theKey,
420                                 TheHandleType&                 theValue) const
421   {
422     const Handle(OpenGl_Resource)& aResource = GetResource (theKey);
423     if (aResource.IsNull())
424     {
425       return Standard_False;
426     }
427 
428     theValue = TheHandleType::DownCast (aResource);
429     return !theValue.IsNull();
430   }
431 
432   //! Register shared resource.
433   //! Notice that after registration caller shouldn't release it by himself -
434   //! it will be automatically released on context destruction.
435   //! @param theKey      - unique identifier, shouldn't be empty;
436   //! @param theResource - new resource to register, shouldn't be NULL.
437   Standard_EXPORT Standard_Boolean ShareResource (const TCollection_AsciiString& theKey,
438                                                   const Handle(OpenGl_Resource)& theResource);
439 
440   //! Release shared resource.
441   //! If there are more than one reference to this resource
442   //! (also used by some other existing object) then call will be ignored.
443   //! This means that current object itself should nullify handle before this call.
444   //! Notice that this is unrecommended operation at all and should be used
445   //! only in case of fat resources to release memory for other needs.
446   //! @param theKey     unique identifier
447   //! @param theToDelay postpone release until next redraw call
448   Standard_EXPORT void ReleaseResource (const TCollection_AsciiString& theKey,
449                                         const Standard_Boolean         theToDelay = Standard_False);
450 
451   //! Append resource to queue for delayed clean up.
452   //! Resources in this queue will be released at next redraw call.
453   template <class T>
DelayedRelease(Handle (T)& theResource)454   void DelayedRelease (Handle(T)& theResource)
455   {
456     myUnusedResources->Prepend (theResource);
457     theResource.Nullify();
458   }
459 
460   //! Clean up the delayed release queue.
461   Standard_EXPORT void ReleaseDelayed();
462 
463   //! Return map of shared resources.
SharedResources() const464   const OpenGl_ResourcesMap& SharedResources() const { return *mySharedResources; }
465 
466   //! @return tool for management of clippings within this context.
ChangeClipping()467   inline OpenGl_Clipping& ChangeClipping() { return myClippingState; }
468 
469   //! @return tool for management of clippings within this context.
Clipping() const470   inline const OpenGl_Clipping& Clipping() const { return myClippingState; }
471 
472   //! @return tool for management of shader programs within this context.
Handle(OpenGl_ShaderManager)473   inline const Handle(OpenGl_ShaderManager)& ShaderManager() const { return myShaderManager; }
474 
475 public:
476 
477   //! Either GL_CLAMP_TO_EDGE (1.2+) or GL_CLAMP (1.1).
TextureWrapClamp() const478   Standard_Integer TextureWrapClamp() const { return myTexClamp; }
479 
480   //! @return true if texture parameters GL_TEXTURE_BASE_LEVEL/GL_TEXTURE_MAX_LEVEL are supported.
HasTextureBaseLevel() const481   Standard_Boolean HasTextureBaseLevel() const
482   {
483   #if !defined(GL_ES_VERSION_2_0)
484     return IsGlGreaterEqual (1, 2);
485   #else
486     return IsGlGreaterEqual (3, 0);
487   #endif
488   }
489 
490   //! Return map of supported texture formats.
Handle(Image_SupportedFormats)491   const Handle(Image_SupportedFormats)& SupportedTextureFormats() const { return mySupportedFormats; }
492 
493   //! @return maximum degree of anisotropy texture filter
MaxDegreeOfAnisotropy() const494   Standard_Integer MaxDegreeOfAnisotropy() const { return myAnisoMax; }
495 
496   //! @return value for GL_MAX_TEXTURE_SIZE
MaxTextureSize() const497   Standard_Integer MaxTextureSize() const { return myMaxTexDim; }
498 
499   //! @return value for GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS
MaxCombinedTextureUnits() const500   Standard_Integer MaxCombinedTextureUnits() const { return myMaxTexCombined; }
501 
502   //! This method returns the multi-texture limit for obsolete fixed-function pipeline.
503   //! Use MaxCombinedTextureUnits() instead for limits for using programmable pipeline.
504   //! @return value for GL_MAX_TEXTURE_UNITS
MaxTextureUnitsFFP() const505   Standard_Integer MaxTextureUnitsFFP() const { return myMaxTexUnitsFFP; }
506 
507   //! Return texture unit to be used for sprites (Graphic3d_TextureUnit_PointSprite by default).
SpriteTextureUnit() const508   Graphic3d_TextureUnit SpriteTextureUnit() const { return mySpriteTexUnit; }
509 
510   //! @return value for GL_MAX_SAMPLES
MaxMsaaSamples() const511   Standard_Integer MaxMsaaSamples() const { return myMaxMsaaSamples; }
512 
513   //! @return maximum FBO width for image dump
MaxDumpSizeX() const514   Standard_Integer MaxDumpSizeX() const { return myMaxDumpSizeX; }
515 
516   //! @return maximum FBO height for image dump
MaxDumpSizeY() const517   Standard_Integer MaxDumpSizeY() const { return myMaxDumpSizeY; }
518 
519   //! @return value for GL_MAX_DRAW_BUFFERS
MaxDrawBuffers() const520   Standard_Integer MaxDrawBuffers() const { return myMaxDrawBuffers; }
521 
522   //! @return value for GL_MAX_COLOR_ATTACHMENTS
MaxColorAttachments() const523   Standard_Integer MaxColorAttachments() const { return myMaxColorAttachments; }
524 
525   //! Get maximum number of clip planes supported by OpenGl.
526   //! This value is implementation dependent. At least 6
527   //! planes should be supported by OpenGl (see specs).
528   //! @return value for GL_MAX_CLIP_PLANES
MaxClipPlanes() const529   Standard_Integer MaxClipPlanes() const { return myMaxClipPlanes; }
530 
531   //! @return TRUE if ray tracing mode is supported
HasRayTracing() const532   Standard_Boolean HasRayTracing() const { return myHasRayTracing; }
533 
534   //! @return TRUE if textures in ray tracing mode are supported
HasRayTracingTextures() const535   Standard_Boolean HasRayTracingTextures() const { return myHasRayTracingTextures; }
536 
537   //! @return TRUE if adaptive screen sampling in ray tracing mode is supported
HasRayTracingAdaptiveSampling() const538   Standard_Boolean HasRayTracingAdaptiveSampling() const { return myHasRayTracingAdaptiveSampling; }
539 
540   //! @return TRUE if atomic adaptive screen sampling in ray tracing mode is supported
HasRayTracingAdaptiveSamplingAtomic() const541   Standard_Boolean HasRayTracingAdaptiveSamplingAtomic() const { return myHasRayTracingAdaptiveSamplingAtomic; }
542 
543   //! Returns TRUE if sRGB rendering is supported.
HasSRGB() const544   bool HasSRGB() const
545   {
546     return hasTexSRGB
547        &&  hasFboSRGB;
548   }
549 
550   //! Returns TRUE if sRGB rendering is supported and permitted.
ToRenderSRGB() const551   bool ToRenderSRGB() const
552   {
553     return HasSRGB()
554        && !caps->sRGBDisable
555        && !caps->ffpEnable;
556   }
557 
558   //! Returns TRUE if window/surface buffer is sRGB-ready.
559   //!
560   //! When offscreen FBOs are created in sRGB, but window is not sRGB-ready,
561   //! blitting into window should be done with manual gamma correction.
562   //!
563   //! In desktop OpenGL, window buffer can be considered as sRGB-ready by default,
564   //! even when application has NOT requested sRGB-ready pixel format,
565   //! and rendering is managed via GL_FRAMEBUFFER_SRGB state.
566   //!
567   //! In OpenGL ES, sRGB-ready window surface should be explicitly requested on construction,
568   //! and cannot be disabled/enabled without GL_EXT_sRGB_write_control extension afterwards
569   //! (GL_FRAMEBUFFER_SRGB can be considered as always tuned ON).
IsWindowSRGB() const570   bool IsWindowSRGB() const { return myIsSRgbWindow; }
571 
572   //! Overrides if window/surface buffer is sRGB-ready or not (initialized with the context).
SetWindowSRGB(bool theIsSRgb)573   void SetWindowSRGB (bool theIsSRgb) { myIsSRgbWindow = theIsSRgb; }
574 
575   //! Convert Quantity_ColorRGBA into vec4
576   //! with conversion or no conversion into non-linear sRGB
577   //! basing on ToRenderSRGB() flag.
Vec4FromQuantityColor(const OpenGl_Vec4 & theColor) const578   OpenGl_Vec4 Vec4FromQuantityColor (const OpenGl_Vec4& theColor) const
579   {
580     return myIsSRgbActive
581          ? Vec4LinearFromQuantityColor(theColor)
582          : Vec4sRGBFromQuantityColor  (theColor);
583   }
584 
585   //! Convert Quantity_ColorRGBA into vec4.
586   //! Quantity_Color is expected to be linear RGB, hence conversion is NOT required
Vec4LinearFromQuantityColor(const OpenGl_Vec4 & theColor) const587   const OpenGl_Vec4& Vec4LinearFromQuantityColor (const OpenGl_Vec4& theColor) const { return theColor; }
588 
589   //! Convert Quantity_ColorRGBA (linear RGB) into non-linear sRGB vec4.
Vec4sRGBFromQuantityColor(const OpenGl_Vec4 & theColor) const590   OpenGl_Vec4 Vec4sRGBFromQuantityColor (const OpenGl_Vec4& theColor) const
591   {
592     return Quantity_ColorRGBA::Convert_LinearRGB_To_sRGB (theColor);
593   }
594 
595   //! Returns TRUE if PBR shading model is supported.
596   //! Basically, feature requires OpenGL 3.0+ / OpenGL ES 3.0+ hardware; more precisely:
597   //! - Graphics hardware with moderate capabilities for compiling long enough GLSL program.
598   //! - FBO (e.g. for baking environment).
599   //! - Multi-texturing with >= 4 units (LUT and IBL textures).
600   //! - GL_RG32F texture format (arbTexRG + arbTexFloat)
601   //! - Cubemap texture lookup textureCubeLod()/textureLod() with LOD index within Fragment Shader,
602   //!   which requires GLSL OpenGL 3.0+ / OpenGL ES 3.0+ or OpenGL 2.1 + GL_EXT_gpu_shader4 extension.
HasPBR() const603   Standard_Boolean HasPBR() const { return myHasPBR; }
604 
605   //! Returns texture unit where Environment Lookup Table is expected to be bound, or 0 if PBR is unavailable.
PBREnvLUTTexUnit() const606   Graphic3d_TextureUnit PBREnvLUTTexUnit() const { return myPBREnvLUTTexUnit; }
607 
608   //! Returns texture unit where Diffuse (irradiance) IBL map's spherical harmonics coefficients is expected to be bound, or 0 if PBR is unavailable.
PBRDiffIBLMapSHTexUnit() const609   Graphic3d_TextureUnit PBRDiffIBLMapSHTexUnit() const { return myPBRDiffIBLMapSHTexUnit; }
610 
611   //! Returns texture unit where Specular IBL map is expected to be bound, or 0 if PBR is unavailable.
PBRSpecIBLMapTexUnit() const612   Graphic3d_TextureUnit PBRSpecIBLMapTexUnit() const { return myPBRSpecIBLMapTexUnit; }
613 
614   //! Returns texture unit where shadow map is expected to be bound, or 0 if unavailable.
ShadowMapTexUnit() const615   Graphic3d_TextureUnit ShadowMapTexUnit() const { return myShadowMapTexUnit; }
616 
617   //! Returns texture unit for occDepthPeelingDepth within enabled Depth Peeling.
DepthPeelingDepthTexUnit() const618   Graphic3d_TextureUnit DepthPeelingDepthTexUnit() const { return myDepthPeelingDepthTexUnit; }
619 
620   //! Returns texture unit for occDepthPeelingFrontColor within enabled Depth Peeling.
DepthPeelingFrontColorTexUnit() const621   Graphic3d_TextureUnit DepthPeelingFrontColorTexUnit() const { return myDepthPeelingFrontColorTexUnit; }
622 
623   //! Returns true if VBO is supported and permitted.
ToUseVbo() const624   inline bool ToUseVbo() const
625   {
626     return core15fwd != NULL
627        && !caps->vboDisable;
628   }
629 
630   //! @return cached state of GL_NORMALIZE.
IsGlNormalizeEnabled() const631   Standard_Boolean IsGlNormalizeEnabled() const { return myIsGlNormalizeEnabled; }
632 
633   //! Sets GL_NORMALIZE enabled or disabled.
634   //! @return old value of the flag
635   Standard_EXPORT Standard_Boolean SetGlNormalizeEnabled (Standard_Boolean isEnabled);
636 
637   //! @return cached state of polygon rasterization mode (glPolygonMode()).
PolygonMode() const638   Standard_Integer PolygonMode() const { return myPolygonMode; }
639 
640   //! Sets polygon rasterization mode (glPolygonMode() function).
641   //! @return old value of the rasterization mode.
642   Standard_EXPORT Standard_Integer SetPolygonMode (const Standard_Integer theMode);
643 
644   //! @return cached enabled state of polygon hatching rasterization.
IsPolygonHatchEnabled() const645   bool IsPolygonHatchEnabled() const { return myHatchIsEnabled; }
646 
647   //! Sets enabled state of polygon hatching rasterization
648   //! without affecting currently selected hatching pattern.
649   //! @return previous state of polygon hatching mode.
650   Standard_EXPORT bool SetPolygonHatchEnabled (const bool theIsEnabled);
651 
652   //! @return cached state of polygon hatch type.
PolygonHatchStyle() const653   Standard_Integer PolygonHatchStyle() const { return myActiveHatchType; }
654 
655   //! Sets polygon hatch pattern.
656   //! Zero-index value is a default alias for solid filling.
657   //! @param the type of hatch supported by base implementation of
658   //! OpenGl_LineAttributes (Aspect_HatchStyle) or the type supported by custom
659   //! implementation derived from OpenGl_LineAttributes class.
660   //! @return old type of hatch.
661   Standard_EXPORT Standard_Integer SetPolygonHatchStyle (const Handle(Graphic3d_HatchStyle)& theStyle);
662 
663   //! Sets and applies current polygon offset.
664   Standard_EXPORT void SetPolygonOffset (const Graphic3d_PolygonOffset& theOffset);
665 
666   //! Returns currently applied polygon offset parameters.
PolygonOffset() const667   const Graphic3d_PolygonOffset& PolygonOffset() const { return myPolygonOffset; }
668 
669   //! Returns camera object.
Handle(Graphic3d_Camera)670   const Handle(Graphic3d_Camera)& Camera() const { return myCamera; }
671 
672   //! Sets camera object to the context and update matrices.
673   Standard_EXPORT void SetCamera (const Handle(Graphic3d_Camera)& theCamera);
674 
675   //! Applies matrix into shader manager stored in ModelWorldState to OpenGl.
676   //! In "model -> world -> view -> projection" it performs:
677   //!     model -> world
678   Standard_EXPORT void ApplyModelWorldMatrix();
679 
680   //! Applies matrix stored in WorldViewState to OpenGl.
681   //! In "model -> world -> view -> projection" it performs:
682   //!     model -> world -> view,
683   //! where model -> world is identical matrix
684   Standard_EXPORT void ApplyWorldViewMatrix();
685 
686   //! Applies combination of matrices stored in ModelWorldState and WorldViewState to OpenGl.
687   //! In "model -> world -> view -> projection" it performs:
688   //!     model -> world -> view
689   Standard_EXPORT void ApplyModelViewMatrix();
690 
691   //! Applies matrix stored in ProjectionState to OpenGl.
692   //! In "model -> world -> view -> projection" it performs:
693   //!                       view -> projection
694   Standard_EXPORT void ApplyProjectionMatrix();
695 
696 public:
697 
698   //! @return messenger instance
Handle(Message_Messenger)699   inline const Handle(Message_Messenger)& Messenger() const
700   {
701     return ::Message::DefaultMessenger();
702   }
703 
704   //! Callback for GL_ARB_debug_output extension
705   //! @param theSource   message source   within GL_DEBUG_SOURCE_   enumeration
706   //! @param theType     message type     within GL_DEBUG_TYPE_     enumeration
707   //! @param theId       message ID       within source
708   //! @param theSeverity message severity within GL_DEBUG_SEVERITY_ enumeration
709   //! @param theMessage  the message itself
710   Standard_EXPORT void PushMessage (const unsigned int theSource,
711                                     const unsigned int theType,
712                                     const unsigned int theId,
713                                     const unsigned int theSeverity,
714                                     const TCollection_ExtendedString& theMessage);
715 
716   //! Adds a filter for messages with theId and theSource (GL_DEBUG_SOURCE_)
717   Standard_EXPORT Standard_Boolean ExcludeMessage (const unsigned int theSource,
718                                                    const unsigned int theId);
719 
720   //! Removes a filter for messages with theId and theSource (GL_DEBUG_SOURCE_)
721   Standard_EXPORT Standard_Boolean IncludeMessage (const unsigned int theSource,
722                                                    const unsigned int theId);
723 
724   //! @return true if OpenGl context supports left and
725   //! right rendering buffers.
HasStereoBuffers() const726   Standard_Boolean HasStereoBuffers() const
727   {
728   #if !defined(GL_ES_VERSION_2_0)
729     return myIsStereoBuffers;
730   #else
731     return Standard_False;
732   #endif
733   }
734 
735 public: //! @name methods to alter or retrieve current state
736 
737   //! Return structure holding frame statistics.
Handle(OpenGl_FrameStats)738   const Handle(OpenGl_FrameStats)& FrameStats() const { return myFrameStats; }
739 
740   //! Set structure holding frame statistics.
741   //! This call makes sense only if application defines OpenGl_FrameStats sub-class.
SetFrameStats(const Handle (OpenGl_FrameStats)& theStats)742   void SetFrameStats (const Handle(OpenGl_FrameStats)& theStats) { myFrameStats = theStats; }
743 
744   //! Return cached viewport definition (x, y, width, height).
Viewport() const745   const Standard_Integer* Viewport() const { return myViewport; }
746 
747   //! Resize the viewport (alias for glViewport).
748   //! @param theRect viewport definition (x, y, width, height)
749   Standard_EXPORT void ResizeViewport (const Standard_Integer theRect[4]);
750 
751   //! Return virtual viewport definition (x, y, width, height).
VirtualViewport() const752   const Standard_Integer* VirtualViewport() const { return myViewportVirt; }
753 
754   //! Return active read buffer.
ReadBuffer()755   Standard_Integer ReadBuffer() { return myReadBuffer; }
756 
757   //! Switch read buffer, wrapper for ::glReadBuffer().
758   Standard_EXPORT void SetReadBuffer (const Standard_Integer theReadBuffer);
759 
760   //! Return active draw buffer attached to a render target referred by index (layout location).
DrawBuffer(Standard_Integer theIndex=0) const761   Standard_Integer DrawBuffer (Standard_Integer theIndex = 0) const
762   {
763     return theIndex >= myDrawBuffers.Lower()
764         && theIndex <= myDrawBuffers.Upper()
765          ? myDrawBuffers.Value (theIndex)
766          : GL_NONE;
767   }
768 
769   //! Switch draw buffer, wrapper for ::glDrawBuffer().
770   Standard_EXPORT void SetDrawBuffer (const Standard_Integer theDrawBuffer);
771 
772   //! Switch draw buffer, wrapper for ::glDrawBuffers (GLsizei, const GLenum*).
773   Standard_EXPORT void SetDrawBuffers (const Standard_Integer theNb, const Standard_Integer* theDrawBuffers);
774 
775   //! Switch read/draw buffers.
SetReadDrawBuffer(const Standard_Integer theBuffer)776   void SetReadDrawBuffer (const Standard_Integer theBuffer)
777   {
778     SetReadBuffer (theBuffer);
779     SetDrawBuffer (theBuffer);
780   }
781 
782   //! Returns cached GL_FRAMEBUFFER_SRGB state.
783   //! If TRUE, GLSL program is expected to write linear RGB color.
784   //! Otherwise, GLSL program might need manually converting result color into sRGB color space.
IsFrameBufferSRGB() const785   bool IsFrameBufferSRGB() const { return myIsSRgbActive; }
786 
787   //! Enables/disables GL_FRAMEBUFFER_SRGB flag.
788   //! This flag can be set to:
789   //! - TRUE when writing into offscreen FBO (always expected to be in sRGB or RGBF formats).
790   //! - TRUE when writing into sRGB-ready window buffer (might require choosing proper pixel format on window creation).
791   //! - FALSE if sRGB rendering is not supported or sRGB-not-ready window buffer is used for drawing.
792   //! @param theIsFbo [in] flag indicating writing into offscreen FBO (always expected sRGB-ready when sRGB FBO is supported)
793   //!                      or into window buffer (FALSE, sRGB-readiness might vary).
794   //! @param theIsSRgb [in] flag indicating off-screen FBO is sRGB-ready
795   Standard_EXPORT void SetFrameBufferSRGB (bool theIsFbo, bool theIsFboSRgb = true);
796 
797   //! Return cached flag indicating writing into color buffer is enabled or disabled (glColorMask).
ColorMaskRGBA() const798   const NCollection_Vec4<bool>& ColorMaskRGBA() const { return myColorMask; }
799 
800   //! Enable/disable writing into color buffer (wrapper for glColorMask).
801   Standard_EXPORT void SetColorMaskRGBA (const NCollection_Vec4<bool>& theToWriteColor);
802 
803   //! Return cached flag indicating writing into color buffer is enabled or disabled (glColorMask).
ColorMask() const804   bool ColorMask() const { return myColorMask.r(); }
805 
806   //! Enable/disable writing into color buffer (wrapper for glColorMask).
807   //! Alpha component writes will be disabled unconditionally in case of caps->buffersOpaqueAlpha.
808   Standard_EXPORT bool SetColorMask (bool theToWriteColor);
809 
810   //! Return TRUE if GL_SAMPLE_ALPHA_TO_COVERAGE usage is allowed.
AllowSampleAlphaToCoverage() const811   bool AllowSampleAlphaToCoverage() const { return myAllowAlphaToCov; }
812 
813   //! Allow GL_SAMPLE_ALPHA_TO_COVERAGE usage.
SetAllowSampleAlphaToCoverage(bool theToEnable)814   void SetAllowSampleAlphaToCoverage (bool theToEnable) { myAllowAlphaToCov = theToEnable; }
815 
816   //! Return GL_SAMPLE_ALPHA_TO_COVERAGE state.
SampleAlphaToCoverage() const817   bool SampleAlphaToCoverage() const { return myAlphaToCoverage; }
818 
819   //! Enable/disable GL_SAMPLE_ALPHA_TO_COVERAGE.
820   Standard_EXPORT bool SetSampleAlphaToCoverage (bool theToEnable);
821 
822   //! Return back face culling state.
ToCullBackFaces() const823   bool ToCullBackFaces() const { return myToCullBackFaces; }
824 
825   //! Enable or disable back face culling (glEnable (GL_CULL_FACE)).
826   Standard_EXPORT void SetCullBackFaces (bool theToEnable);
827 
828   //! Fetch OpenGl context state. This class tracks value of several OpenGl
829   //! state variables. Consulting the cached values is quicker than
830   //! doing the same via OpenGl API. Call this method if any of the controlled
831   //! OpenGl state variables has a possibility of being out-of-date.
832   Standard_EXPORT void FetchState();
833 
834   //! @return active textures
Handle(OpenGl_TextureSet)835   const Handle(OpenGl_TextureSet)& ActiveTextures() const { return myActiveTextures; }
836 
837   //! Bind specified texture set to current context taking into account active GLSL program.
838   Standard_DEPRECATED("BindTextures() with explicit GLSL program should be used instead")
Handle(OpenGl_TextureSet)839   Handle(OpenGl_TextureSet) BindTextures (const Handle(OpenGl_TextureSet)& theTextures)
840   {
841     return BindTextures (theTextures, myActiveProgram);
842   }
843 
844   //! Bind specified texture set to current context, or unbind previous one when NULL specified.
845   //! @param theTextures [in] texture set to bind
846   //! @param theProgram  [in] program attributes; when not NULL,
847   //!                         mock textures will be bound to texture units expected by GLSL program, but undefined by texture set
848   //! @return previous texture set
849   Standard_EXPORT Handle(OpenGl_TextureSet) BindTextures (const Handle(OpenGl_TextureSet)& theTextures,
850                                                           const Handle(OpenGl_ShaderProgram)& theProgram);
851 
852   //! @return active GLSL program
Handle(OpenGl_ShaderProgram)853   const Handle(OpenGl_ShaderProgram)& ActiveProgram() const
854   {
855     return myActiveProgram;
856   }
857 
858   //! Bind specified program to current context,
859   //! or unbind previous one when NULL specified.
860   //! @return true if some program is bound to context
861   Standard_EXPORT Standard_Boolean BindProgram (const Handle(OpenGl_ShaderProgram)& theProgram);
862 
863   //! Setup current shading material.
864   Standard_EXPORT void SetShadingMaterial (const OpenGl_Aspects* theAspect,
865                                            const Handle(Graphic3d_PresentationAttributes)& theHighlight);
866 
867   //! Checks if transparency is required for the given aspect and highlight style.
868   Standard_EXPORT static Standard_Boolean CheckIsTransparent (const OpenGl_Aspects* theAspect,
869                                                               const Handle(Graphic3d_PresentationAttributes)& theHighlight,
870                                                               Standard_ShortReal& theAlphaFront,
871                                                               Standard_ShortReal& theAlphaBack);
872 
873   //! Checks if transparency is required for the given aspect and highlight style.
CheckIsTransparent(const OpenGl_Aspects * theAspect,const Handle (Graphic3d_PresentationAttributes)& theHighlight)874   static Standard_Boolean CheckIsTransparent (const OpenGl_Aspects* theAspect,
875                                               const Handle(Graphic3d_PresentationAttributes)& theHighlight)
876   {
877     Standard_ShortReal anAlphaFront = 1.0f, anAlphaBack = 1.0f;
878     return CheckIsTransparent (theAspect, theHighlight, anAlphaFront, anAlphaBack);
879   }
880 
881   //! Setup current color.
882   Standard_EXPORT void SetColor4fv (const OpenGl_Vec4& theColor);
883 
884   //! Setup type of line.
885   Standard_EXPORT void SetTypeOfLine (const Aspect_TypeOfLine  theType,
886                                       const Standard_ShortReal theFactor = 1.0f);
887 
888   //! Setup stipple line pattern with 1.0f factor; wrapper for glLineStipple().
SetLineStipple(const uint16_t thePattern)889   void SetLineStipple (const uint16_t thePattern) { SetLineStipple (1.0f, thePattern); }
890 
891   //! Setup type of line; wrapper for glLineStipple().
892   Standard_EXPORT void SetLineStipple (const Standard_ShortReal theFactor,
893                                        const uint16_t thePattern);
894 
895   //! Setup width of line.
896   Standard_EXPORT void SetLineWidth (const Standard_ShortReal theWidth);
897 
898   //! Setup point size.
899   Standard_EXPORT void SetPointSize (const Standard_ShortReal theSize);
900 
901   //! Setup point sprite origin using GL_POINT_SPRITE_COORD_ORIGIN state:
902   //! - GL_UPPER_LEFT when GLSL program is active;
903   //!   flipping should be handled in GLSL program for compatibility with OpenGL ES
904   //! - GL_LOWER_LEFT for FFP
905   Standard_EXPORT void SetPointSpriteOrigin();
906 
907   //! Setup texture matrix to active GLSL program or to FFP global state using glMatrixMode (GL_TEXTURE).
908   //! @param theParams    [in] texture parameters
909   //! @param theIsTopDown [in] texture top-down flag
910   Standard_EXPORT void SetTextureMatrix (const Handle(Graphic3d_TextureParams)& theParams,
911                                          const Standard_Boolean theIsTopDown);
912 
913   //! Bind default Vertex Array Object
914   Standard_EXPORT void BindDefaultVao();
915 
916   //! Default Frame Buffer Object.
Handle(OpenGl_FrameBuffer)917   const Handle(OpenGl_FrameBuffer)& DefaultFrameBuffer() const
918   {
919     return myDefaultFbo;
920   }
921 
922   //! Setup new Default Frame Buffer Object and return previously set.
923   //! This call doesn't change Active FBO!
924   Standard_EXPORT Handle(OpenGl_FrameBuffer) SetDefaultFrameBuffer (const Handle(OpenGl_FrameBuffer)& theFbo);
925 
926   //! Return debug context initialization state.
IsDebugContext() const927   Standard_Boolean IsDebugContext() const
928   {
929     return myIsGlDebugCtx;
930   }
931 
932   Standard_EXPORT void EnableFeatures() const;
933 
934   Standard_EXPORT void DisableFeatures() const;
935 
936   //! Return resolution for rendering text.
Resolution() const937   unsigned int Resolution() const { return myResolution; }
938 
939   //! Resolution scale factor (rendered resolution to standard resolution).
940   //! This scaling factor for parameters like text size to be properly displayed on device (screen / printer).
ResolutionRatio() const941   Standard_ShortReal ResolutionRatio() const { return myResolutionRatio; }
942 
943   //! Rendering scale factor (rendering viewport height to real window buffer height).
RenderScale() const944   Standard_ShortReal RenderScale() const { return myRenderScale; }
945 
946   //! Return TRUE if rendering scale factor is not 1.
HasRenderScale() const947   Standard_Boolean HasRenderScale() const { return Abs (myRenderScale - 1.0f) > 0.0001f; }
948 
949   //! Rendering scale factor (inverted value).
RenderScaleInv() const950   Standard_ShortReal RenderScaleInv() const { return myRenderScaleInv; }
951 
952   //! Return scale factor for line width.
LineWidthScale() const953   Standard_ShortReal LineWidthScale() const { return myLineWidthScale; }
954 
955   //! Set resolution ratio.
956   //! Note that this method rounds @theRatio to nearest integer.
SetResolution(unsigned int theResolution,Standard_ShortReal theRatio,Standard_ShortReal theScale)957   void SetResolution (unsigned int theResolution,
958                       Standard_ShortReal theRatio,
959                       Standard_ShortReal theScale)
960   {
961     myResolution      = (unsigned int )(theScale * theResolution + 0.5f);
962     myRenderScale     = theScale;
963     myRenderScaleInv  = 1.0f / theScale;
964     SetResolutionRatio (theRatio * theScale);
965   }
966 
967   //! Set resolution ratio.
968   //! Note that this method rounds @theRatio to nearest integer.
SetResolutionRatio(const Standard_ShortReal theRatio)969   void SetResolutionRatio (const Standard_ShortReal theRatio)
970   {
971     myResolutionRatio = theRatio;
972     myLineWidthScale  = Max (1.0f, std::floor (theRatio + 0.5f));
973   }
974 
975   //! Return line feater width in pixels.
LineFeather() const976   Standard_ShortReal LineFeather() const { return myLineFeather; }
977 
978   //! Set line feater width.
SetLineFeather(Standard_ShortReal theValue)979   void SetLineFeather(Standard_ShortReal theValue) { myLineFeather = theValue; }
980 
981   //! Wrapper over glGetBufferSubData(), implemented as:
982   //! - OpenGL 1.5+ (desktop) via glGetBufferSubData();
983   //! - OpenGL ES 3.0+ via glMapBufferRange();
984   //! - WebGL 2.0+ via gl.getBufferSubData().
985   //! @param theTarget [in] target buffer to map
986   //! @param theOffset [in] offset to the beginning of sub-data
987   //! @param theSize   [in] number of bytes to read
988   //! @param theData  [out] destination pointer to fill
989   //! @return FALSE if functionality is unavailable
990   Standard_EXPORT bool GetBufferSubData (GLenum theTarget, GLintptr theOffset, GLsizeiptr theSize, void* theData);
991 
992   //! Return Graphics Driver's vendor.
Vendor() const993   const TCollection_AsciiString& Vendor() const { return myVendor; }
994 
995   //! Dumps the content of me into the stream
996   Standard_EXPORT void DumpJson (Standard_OStream& theOStream, Standard_Integer theDepth = -1) const;
997 
998   //! Dumps the content of openGL state into the stream
999   Standard_EXPORT static void DumpJsonOpenGlState (Standard_OStream& theOStream, Standard_Integer theDepth = -1);
1000 
1001   //! Set GL_SHADE_MODEL value.
1002   Standard_EXPORT void SetShadeModel (Graphic3d_TypeOfShadingModel theModel);
1003 
1004 private:
1005 
1006   //! Wrapper to system function to retrieve GL function pointer by name.
1007   Standard_EXPORT void* findProc (const char* theFuncName);
1008 
1009   //! Print error if not all functions have been exported by context for reported version.
1010   //! Note that this will never happen when using GLX, since returned functions can not be validated.
1011   //! @param theGlVerMajor the OpenGL major version with missing functions
1012   //! @param theGlVerMinor the OpenGL minor version with missing functions
1013   //! @param theLastFailedProc function name which cannot be found
1014   Standard_EXPORT void checkWrongVersion (Standard_Integer theGlVerMajor, Standard_Integer theGlVerMinor,
1015                                           const char* theLastFailedProc);
1016 
1017   //! Private initialization function that should be called only once.
1018   Standard_EXPORT void init (const Standard_Boolean theIsCoreProfile);
1019 
1020 public: //! @name core profiles
1021 
1022   OpenGl_GlCore11*     core11ffp;  //!< OpenGL 1.1 core functionality
1023   OpenGl_GlCore11Fwd*  core11fwd;  //!< OpenGL 1.1 without deprecated entry points
1024   OpenGl_GlCore15*     core15;     //!< OpenGL 1.5 without deprecated entry points
1025   OpenGl_GlCore20*     core20;     //!< OpenGL 2.0 without deprecated entry points
1026   OpenGl_GlCore30*     core30;     //!< OpenGL 3.0 without deprecated entry points
1027   OpenGl_GlCore32*     core32;     //!< OpenGL 3.2 core profile
1028   OpenGl_GlCore33*     core33;     //!< OpenGL 3.3 core profile
1029   OpenGl_GlCore41*     core41;     //!< OpenGL 4.1 core profile
1030   OpenGl_GlCore42*     core42;     //!< OpenGL 4.2 core profile
1031   OpenGl_GlCore43*     core43;     //!< OpenGL 4.3 core profile
1032   OpenGl_GlCore44*     core44;     //!< OpenGL 4.4 core profile
1033   OpenGl_GlCore45*     core45;     //!< OpenGL 4.5 core profile
1034   OpenGl_GlCore46*     core46;     //!< OpenGL 4.6 core profile
1035 
1036   OpenGl_GlCore15*     core15fwd;  //!< obsolete entry left for code portability; core15 should be used instead
1037   OpenGl_GlCore20*     core20fwd;  //!< obsolete entry left for code portability; core20 should be used instead
1038 
1039   Handle(OpenGl_Caps) caps; //!< context options
1040 
1041 public: //! @name extensions
1042 
1043   Standard_Boolean       hasGetBufferData;   //!< flag indicating if GetBufferSubData() is supported
1044   Standard_Boolean       hasPackRowLength;   //!< supporting of GL_PACK_ROW_LENGTH   parameters (any desktop OpenGL; OpenGL ES 3.0)
1045   Standard_Boolean       hasUnpackRowLength; //!< supporting of GL_UNPACK_ROW_LENGTH parameters (any desktop OpenGL; OpenGL ES 3.0)
1046   Standard_Boolean       hasHighp;           //!< highp in GLSL ES fragment shader is supported
1047   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)
1048   Standard_Boolean       hasTexRGBA8;        //!< always available on desktop; on OpenGL ES - since 3.0 or as extension GL_OES_rgb8_rgba8
1049   Standard_Boolean       hasTexFloatLinear;  //!< texture-filterable state for 32-bit floating texture formats (always on desktop, GL_OES_texture_float_linear within OpenGL ES)
1050   Standard_Boolean       hasTexSRGB;         //!< sRGB texture    formats (desktop OpenGL 2.1, OpenGL ES 3.0 or OpenGL ES 2.0 + GL_EXT_sRGB)
1051   Standard_Boolean       hasFboSRGB;         //!< sRGB FBO render targets (desktop OpenGL 2.1, OpenGL ES 3.0)
1052   Standard_Boolean       hasSRGBControl;     //!< sRGB write control (any desktop OpenGL, OpenGL ES + GL_EXT_sRGB_write_control extension)
1053   Standard_Boolean       hasFboRenderMipmap; //!< FBO render target could be non-zero mipmap level of texture
1054   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)
1055   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
1056   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)
1057   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)
1058   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)
1059   OpenGl_FeatureFlag     hasSampleVariables; //!< Complex flag indicating support of MSAA variables in GLSL shader (desktop OpenGL 4.0, GL_ARB_sample_shading)
1060   OpenGl_FeatureFlag     hasGeometryStage;   //!< Complex flag indicating support of Geometry shader (desktop OpenGL 3.2, OpenGL ES 3.2, GL_EXT_geometry_shader)
1061   Standard_Boolean       arbDrawBuffers;     //!< GL_ARB_draw_buffers
1062   Standard_Boolean       arbNPTW;            //!< GL_ARB_texture_non_power_of_two
1063   Standard_Boolean       arbTexRG;           //!< GL_ARB_texture_rg
1064   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); @sa hasTexFloatLinear for linear filtering support
1065   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)
1066   OpenGl_ArbTexBindless* arbTexBindless;     //!< GL_ARB_bindless_texture
1067   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)
1068   Standard_Boolean       arbTboRGB32;        //!< GL_ARB_texture_buffer_object_rgb32 (3-component TBO), in core since 4.0 (on OpenGL ES - since 3.2)
1069   Standard_Boolean       arbClipControl;     //!< GL_ARB_clip_control, in core since 4.5
1070   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)
1071   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)
1072   OpenGl_ArbFBO*         arbFBO;             //!< GL_ARB_framebuffer_object
1073   OpenGl_ArbFBOBlit*     arbFBOBlit;         //!< glBlitFramebuffer function, moved out from OpenGl_ArbFBO structure for compatibility with OpenGL ES 2.0
1074   Standard_Boolean       arbSampleShading;   //!< GL_ARB_sample_shading
1075   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)
1076   Standard_Boolean       extFragDepth;       //!< GL_EXT_frag_depth on OpenGL ES 2.0 (gl_FragDepthEXT built-in variable, before OpenGL ES 3.0)
1077   Standard_Boolean       extDrawBuffers;     //!< GL_EXT_draw_buffers
1078   OpenGl_ExtGS*          extGS;              //!< GL_EXT_geometry_shader4
1079   Standard_Boolean       extBgra;            //!< GL_EXT_bgra or GL_EXT_texture_format_BGRA8888 on OpenGL ES
1080   Standard_Boolean       extAnis;            //!< GL_EXT_texture_filter_anisotropic
1081   Standard_Boolean       extPDS;             //!< GL_EXT_packed_depth_stencil
1082   Standard_Boolean       atiMem;             //!< GL_ATI_meminfo
1083   Standard_Boolean       nvxMem;             //!< GL_NVX_gpu_memory_info
1084   Standard_Boolean       oesSampleVariables; //!< GL_OES_sample_variables
1085   Standard_Boolean       oesStdDerivatives;  //!< GL_OES_standard_derivatives
1086 
1087 public: //! @name public properties tracking current state
1088 
1089   OpenGl_MatrixState<Standard_ShortReal> ModelWorldState; //!< state of orientation matrix
1090   OpenGl_MatrixState<Standard_ShortReal> WorldViewState;  //!< state of orientation matrix
1091   OpenGl_MatrixState<Standard_ShortReal> ProjectionState; //!< state of projection  matrix
1092 
1093 private: // system-dependent fields
1094 
1095   Aspect_Drawable         myWindow;   //!< surface           EGLSurface | HWND  | GLXDrawable
1096   Aspect_Display          myDisplay;  //!< display           EGLDisplay | HDC   | Display*
1097   Aspect_RenderingContext myGContext; //!< rendering context EGLContext | HGLRC | GLXContext | EAGLContext* | NSOpenGLContext*
1098 
1099 private: // context info
1100 
1101   typedef NCollection_Shared< NCollection_DataMap<TCollection_AsciiString, Standard_Integer> > OpenGl_DelayReleaseMap;
1102   typedef NCollection_Shared< NCollection_List<Handle(OpenGl_Resource)> > OpenGl_ResourcesStack;
1103 
1104   Handle(OpenGl_ResourcesMap)    mySharedResources; //!< shared resources with unique identification key
1105   Handle(OpenGl_DelayReleaseMap) myDelayed;         //!< shared resources for delayed release
1106   Handle(OpenGl_ResourcesStack)  myUnusedResources; //!< stack of resources for delayed clean up
1107 
1108   OpenGl_Clipping myClippingState; //!< state of clip planes
1109 
1110   void*            myGlLibHandle;          //!< optional handle to GL library
1111   NCollection_Handle<OpenGl_GlFunctions>
1112                    myFuncs;                //!< mega structure for all GL functions
1113   Handle(Image_SupportedFormats)
1114                    mySupportedFormats;     //!< map of supported texture formats
1115   Standard_Integer myAnisoMax;             //!< maximum level of anisotropy texture filter
1116   Standard_Integer myTexClamp;             //!< either GL_CLAMP_TO_EDGE (1.2+) or GL_CLAMP (1.1)
1117   Standard_Integer myMaxTexDim;            //!< value for GL_MAX_TEXTURE_SIZE
1118   Standard_Integer myMaxTexCombined;       //!< value for GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS
1119   Standard_Integer myMaxTexUnitsFFP;       //!< value for GL_MAX_TEXTURE_UNITS (fixed-function pipeline only)
1120   Standard_Integer myMaxDumpSizeX;         //!< maximum FBO width  for image dump
1121   Standard_Integer myMaxDumpSizeY;         //!< maximum FBO height for image dump
1122   Standard_Integer myMaxClipPlanes;        //!< value for GL_MAX_CLIP_PLANES
1123   Standard_Integer myMaxMsaaSamples;       //!< value for GL_MAX_SAMPLES
1124   Standard_Integer myMaxDrawBuffers;       //!< value for GL_MAX_DRAW_BUFFERS
1125   Standard_Integer myMaxColorAttachments;  //!< value for GL_MAX_COLOR_ATTACHMENTS
1126   Standard_Integer myGlVerMajor;           //!< cached GL version major number
1127   Standard_Integer myGlVerMinor;           //!< cached GL version minor number
1128   Standard_Boolean myIsInitialized;        //!< flag indicates initialization state
1129   Standard_Boolean myIsStereoBuffers;      //!< context supports stereo buffering
1130   Standard_Boolean myIsGlNormalizeEnabled; //!< GL_NORMALIZE flag
1131                                            //!< Used to tell OpenGl that normals should be normalized
1132   Graphic3d_TextureUnit mySpriteTexUnit;   //!< sampler2D occSamplerPointSprite, texture unit for point sprite texture
1133 
1134   Standard_Boolean myHasRayTracing;                 //! indicates whether ray tracing mode is supported
1135   Standard_Boolean myHasRayTracingTextures;         //! indicates whether textures in ray tracing mode are supported
1136   Standard_Boolean myHasRayTracingAdaptiveSampling; //! indicates whether adaptive screen sampling in ray tracing mode is supported
1137   Standard_Boolean myHasRayTracingAdaptiveSamplingAtomic; //! indicates whether atomic adaptive screen sampling in ray tracing mode is supported
1138 
1139   Standard_Boolean myHasPBR;                      //!< indicates whether PBR shading model is supported
1140   Graphic3d_TextureUnit myPBREnvLUTTexUnit;       //!< sampler2D occEnvLUT, texture unit where environment lookup table is expected to be binded (0 if PBR is not supported)
1141   Graphic3d_TextureUnit myPBRDiffIBLMapSHTexUnit; //!< sampler2D occDiffIBLMapSHCoeffs, texture unit where diffuse (irradiance) IBL map's spherical harmonics coefficients is expected to  be binded
1142                                                   //!  (0 if PBR is not supported)
1143   Graphic3d_TextureUnit myPBRSpecIBLMapTexUnit;   //!< samplerCube occSpecIBLMap, texture unit where specular IBL map is expected to  be binded (0 if PBR is not supported)
1144   Graphic3d_TextureUnit myShadowMapTexUnit;       //!< sampler2D occShadowMapSampler
1145 
1146   Graphic3d_TextureUnit myDepthPeelingDepthTexUnit;      //!< sampler2D occDepthPeelingDepth, texture unit for Depth Peeling lookups
1147   Graphic3d_TextureUnit myDepthPeelingFrontColorTexUnit; //!< sampler2D occDepthPeelingFrontColor, texture unit for Depth Peeling lookups
1148 
1149   Handle(OpenGl_ShaderManager) myShaderManager; //! support object for managing shader programs
1150 
1151 private: //! @name fields tracking current state
1152 
1153   Handle(Graphic3d_Camera)      myCamera;          //!< active camera object
1154   Handle(OpenGl_FrameStats)     myFrameStats;      //!< structure accumulating frame statistics
1155   Handle(OpenGl_ShaderProgram)  myActiveProgram;   //!< currently active GLSL program
1156   Handle(OpenGl_TextureSet)     myActiveTextures;  //!< currently bound textures
1157                                                    //!< currently active sampler objects
1158   Standard_Integer              myActiveMockTextures; //!< currently active mock sampler objects
1159   Handle(OpenGl_FrameBuffer)    myDefaultFbo;      //!< default Frame Buffer Object
1160   Handle(OpenGl_LineAttributes) myHatchStyles;     //!< resource holding predefined hatch styles patterns
1161   Standard_Integer              myActiveHatchType; //!< currently activated type of polygon hatch
1162   Standard_Boolean              myHatchIsEnabled;  //!< current enabled state of polygon hatching rasterization
1163   Handle(OpenGl_Texture)        myTextureRgbaBlack;//!< mock black texture returning (0, 0, 0, 0)
1164   Handle(OpenGl_Texture)        myTextureRgbaWhite;//!< mock white texture returning (1, 1, 1, 1)
1165   Standard_Integer              myViewport[4];     //!< current viewport
1166   Standard_Integer              myViewportVirt[4]; //!< virtual viewport
1167   Standard_Integer              myPointSpriteOrig; //!< GL_POINT_SPRITE_COORD_ORIGIN state (GL_UPPER_LEFT by default)
1168   Standard_Integer              myRenderMode;      //!< value for active rendering mode
1169   Standard_Integer              myShadeModel;      //!< currently used shade model (glShadeModel)
1170   Standard_Integer              myPolygonMode;     //!< currently used polygon rasterization mode (glPolygonMode)
1171   Graphic3d_PolygonOffset       myPolygonOffset;   //!< currently applied polygon offset
1172   bool                          myToCullBackFaces; //!< back face culling mode enabled state (glIsEnabled (GL_CULL_FACE))
1173   Standard_Integer              myReadBuffer;      //!< current read buffer
1174   NCollection_Array1<Standard_Integer>
1175                                 myDrawBuffers;     //!< current draw buffers
1176   unsigned int                  myDefaultVao;      //!< default Vertex Array Object
1177   NCollection_Vec4<bool>        myColorMask;       //!< flag indicating writing into color buffer is enabled or disabled (glColorMask)
1178   Standard_Boolean              myAllowAlphaToCov; //!< flag allowing   GL_SAMPLE_ALPHA_TO_COVERAGE usage
1179   Standard_Boolean              myAlphaToCoverage; //!< flag indicating GL_SAMPLE_ALPHA_TO_COVERAGE state
1180   Standard_Boolean              myIsGlDebugCtx;    //!< debug context initialization state
1181   Standard_Boolean              myIsSRgbWindow;    //!< indicates that window buffer is sRGB-ready
1182   Standard_Boolean              myIsSRgbActive;    //!< flag indicating GL_FRAMEBUFFER_SRGB state
1183   TCollection_AsciiString       myVendor;          //!< Graphics Driver's vendor
1184   TColStd_PackedMapOfInteger    myFilters[6];      //!< messages suppressing filter (for sources from GL_DEBUG_SOURCE_API_ARB to GL_DEBUG_SOURCE_OTHER_ARB)
1185   unsigned int                  myResolution;      //!< Pixels density (PPI), defines scaling factor for parameters like text size
1186   Standard_ShortReal            myResolutionRatio; //!< scaling factor for parameters like text size
1187                                                    //!  to be properly displayed on device (screen / printer)
1188   Standard_ShortReal            myLineWidthScale;  //!< scaling factor for line width
1189   Standard_ShortReal            myLineFeather;     //!< line feater width in pixels
1190   Standard_ShortReal            myRenderScale;     //!< scaling factor for rendering resolution
1191   Standard_ShortReal            myRenderScaleInv;  //!< scaling factor for rendering resolution (inverted value)
1192   OpenGl_Material               myMaterial;        //!< current front/back material state (cached to reduce GL context updates)
1193 
1194 private:
1195 
1196   //! Copying allowed only within Handles
1197   OpenGl_Context            (const OpenGl_Context& );
1198   OpenGl_Context& operator= (const OpenGl_Context& );
1199 
1200 };
1201 
1202 #endif // _OpenGl_Context_H__
1203