0030748: Visualization - Marker displayed in immediate layer ruins QT Quick view...
[occt.git] / src / OpenGl / OpenGl_View_Raytrace.cxx
1 // Created on: 2015-02-20
2 // Created by: Denis BOGOLEPOV
3 // Copyright (c) 2015 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 #include <OpenGl_View.hxx>
17
18 #include <Graphic3d_TextureParams.hxx>
19 #include <OpenGl_PrimitiveArray.hxx>
20 #include <OpenGl_VertexBuffer.hxx>
21 #include <OpenGl_GlCore44.hxx>
22 #include <OSD_Protection.hxx>
23 #include <OSD_File.hxx>
24
25 #include "../Shaders/Shaders_RaytraceBase_vs.pxx"
26 #include "../Shaders/Shaders_RaytraceBase_fs.pxx"
27 #include "../Shaders/Shaders_PathtraceBase_fs.pxx"
28 #include "../Shaders/Shaders_RaytraceRender_fs.pxx"
29 #include "../Shaders/Shaders_RaytraceSmooth_fs.pxx"
30 #include "../Shaders/Shaders_Display_fs.pxx"
31
32 using namespace OpenGl_Raytrace;
33
34 //! Use this macro to output ray-tracing debug info
35 // #define RAY_TRACE_PRINT_INFO
36
37 #ifdef RAY_TRACE_PRINT_INFO
38   #include <OSD_Timer.hxx>
39 #endif
40
41 namespace
42 {
43   static const OpenGl_Vec4 THE_WHITE_COLOR (1.0f, 1.0f, 1.0f, 1.0f);
44   static const OpenGl_Vec4 THE_BLACK_COLOR (0.0f, 0.0f, 0.0f, 1.0f);
45 }
46
47 namespace
48 {
49   //! Defines OpenGL texture samplers.
50   static const Graphic3d_TextureUnit OpenGl_RT_EnvironmentMapTexture = Graphic3d_TextureUnit_0;
51
52   static const Graphic3d_TextureUnit OpenGl_RT_SceneNodeInfoTexture  = Graphic3d_TextureUnit_1;
53   static const Graphic3d_TextureUnit OpenGl_RT_SceneMinPointTexture  = Graphic3d_TextureUnit_2;
54   static const Graphic3d_TextureUnit OpenGl_RT_SceneMaxPointTexture  = Graphic3d_TextureUnit_3;
55   static const Graphic3d_TextureUnit OpenGl_RT_SceneTransformTexture = Graphic3d_TextureUnit_4;
56
57   static const Graphic3d_TextureUnit OpenGl_RT_GeometryVertexTexture = Graphic3d_TextureUnit_5;
58   static const Graphic3d_TextureUnit OpenGl_RT_GeometryNormalTexture = Graphic3d_TextureUnit_6;
59   static const Graphic3d_TextureUnit OpenGl_RT_GeometryTexCrdTexture = Graphic3d_TextureUnit_7;
60   static const Graphic3d_TextureUnit OpenGl_RT_GeometryTriangTexture = Graphic3d_TextureUnit_8;
61
62   static const Graphic3d_TextureUnit OpenGl_RT_RaytraceMaterialTexture = Graphic3d_TextureUnit_9;
63   static const Graphic3d_TextureUnit OpenGl_RT_RaytraceLightSrcTexture = Graphic3d_TextureUnit_10;
64
65   static const Graphic3d_TextureUnit OpenGl_RT_FsaaInputTexture = Graphic3d_TextureUnit_11;
66   static const Graphic3d_TextureUnit OpenGl_RT_PrevAccumTexture = Graphic3d_TextureUnit_12;
67
68   static const Graphic3d_TextureUnit OpenGl_RT_RaytraceDepthTexture = Graphic3d_TextureUnit_13;
69 }
70
71 // =======================================================================
72 // function : updateRaytraceGeometry
73 // purpose  : Updates 3D scene geometry for ray-tracing
74 // =======================================================================
75 Standard_Boolean OpenGl_View::updateRaytraceGeometry (const RaytraceUpdateMode      theMode,
76                                                       const Standard_Integer        theViewId,
77                                                       const Handle(OpenGl_Context)& theGlContext)
78 {
79   // In 'check' mode (OpenGl_GUM_CHECK) the scene geometry is analyzed for
80   // modifications. This is light-weight procedure performed on each frame
81   if (theMode == OpenGl_GUM_CHECK)
82   {
83     if (myRaytraceLayerListState != myZLayers.ModificationStateOfRaytracable())
84     {
85       return updateRaytraceGeometry (OpenGl_GUM_PREPARE, theViewId, theGlContext);
86     }
87   }
88   else if (theMode == OpenGl_GUM_PREPARE)
89   {
90     myRaytraceGeometry.ClearMaterials();
91
92     myArrayToTrianglesMap.clear();
93
94     myIsRaytraceDataValid = Standard_False;
95   }
96
97   // The set of processed structures (reflected to ray-tracing)
98   // This set is used to remove out-of-date records from the
99   // hash map of structures
100   std::set<const OpenGl_Structure*> anElements;
101
102   // Set to store all currently visible OpenGL primitive arrays
103   // applicable for ray-tracing
104   std::set<Standard_Size> anArrayIDs;
105
106   // Set to store all non-raytracable elements allowing tracking
107   // of changes in OpenGL scene (only for path tracing)
108   std::set<Standard_Integer> aNonRaytraceIDs;
109
110   const OpenGl_Layer& aLayer = myZLayers.Layer (Graphic3d_ZLayerId_Default);
111
112   if (aLayer.NbStructures() != 0)
113   {
114     const Graphic3d_ArrayOfIndexedMapOfStructure& aStructArray = aLayer.ArrayOfStructures();
115
116     for (Standard_Integer anIndex = 0; anIndex < aStructArray.Length(); ++anIndex)
117     {
118       for (OpenGl_Structure::StructIterator aStructIt (aStructArray.Value (anIndex)); aStructIt.More(); aStructIt.Next())
119       {
120         const OpenGl_Structure* aStructure = aStructIt.Value();
121
122         if (theMode == OpenGl_GUM_CHECK)
123         {
124           if (toUpdateStructure (aStructure))
125           {
126             return updateRaytraceGeometry (OpenGl_GUM_PREPARE, theViewId, theGlContext);
127           }
128           else if (aStructure->IsVisible() && myRaytraceParameters.GlobalIllumination)
129           {
130             aNonRaytraceIDs.insert (aStructure->highlight ? aStructure->Id : -aStructure->Id);
131           }
132         }
133         else if (theMode == OpenGl_GUM_PREPARE)
134         {
135           if (!aStructure->IsRaytracable() || !aStructure->IsVisible())
136           {
137             continue;
138           }
139           else if (!aStructure->ViewAffinity.IsNull() && !aStructure->ViewAffinity->IsVisible (theViewId))
140           {
141             continue;
142           }
143
144           for (OpenGl_Structure::GroupIterator aGroupIter (aStructure->Groups()); aGroupIter.More(); aGroupIter.Next())
145           {
146             // Extract OpenGL elements from the group (primitives arrays)
147             for (const OpenGl_ElementNode* aNode = aGroupIter.Value()->FirstNode(); aNode != NULL; aNode = aNode->next)
148             {
149               OpenGl_PrimitiveArray* aPrimArray = dynamic_cast<OpenGl_PrimitiveArray*> (aNode->elem);
150
151               if (aPrimArray != NULL)
152               {
153                 anArrayIDs.insert (aPrimArray->GetUID());
154               }
155             }
156           }
157         }
158         else if (theMode == OpenGl_GUM_REBUILD)
159         {
160           if (!aStructure->IsRaytracable())
161           {
162             continue;
163           }
164           else if (addRaytraceStructure (aStructure, theGlContext))
165           {
166             anElements.insert (aStructure); // structure was processed
167           }
168         }
169       }
170     }
171   }
172
173   if (theMode == OpenGl_GUM_PREPARE)
174   {
175     BVH_ObjectSet<Standard_ShortReal, 3>::BVH_ObjectList anUnchangedObjects;
176
177     // Filter out unchanged objects so only their transformations and materials
178     // will be updated (and newly added objects will be processed from scratch)
179     for (Standard_Integer anObjIdx = 0; anObjIdx < myRaytraceGeometry.Size(); ++anObjIdx)
180     {
181       OpenGl_TriangleSet* aTriangleSet = dynamic_cast<OpenGl_TriangleSet*> (
182         myRaytraceGeometry.Objects().ChangeValue (anObjIdx).operator->());
183
184       if (aTriangleSet == NULL)
185       {
186         continue;
187       }
188
189       if (anArrayIDs.find (aTriangleSet->AssociatedPArrayID()) != anArrayIDs.end())
190       {
191         anUnchangedObjects.Append (myRaytraceGeometry.Objects().Value (anObjIdx));
192
193         myArrayToTrianglesMap[aTriangleSet->AssociatedPArrayID()] = aTriangleSet;
194       }
195     }
196
197     myRaytraceGeometry.Objects() = anUnchangedObjects;
198
199     return updateRaytraceGeometry (OpenGl_GUM_REBUILD, theViewId, theGlContext);
200   }
201   else if (theMode == OpenGl_GUM_REBUILD)
202   {
203     // Actualize the hash map of structures - remove out-of-date records
204     std::map<const OpenGl_Structure*, StructState>::iterator anIter = myStructureStates.begin();
205
206     while (anIter != myStructureStates.end())
207     {
208       if (anElements.find (anIter->first) == anElements.end())
209       {
210         myStructureStates.erase (anIter++);
211       }
212       else
213       {
214         ++anIter;
215       }
216     }
217
218     // Actualize OpenGL layer list state
219     myRaytraceLayerListState = myZLayers.ModificationStateOfRaytracable();
220
221     // Rebuild two-level acceleration structure
222     myRaytraceGeometry.ProcessAcceleration();
223
224     myRaytraceSceneRadius = 2.f /* scale factor */ * std::max (
225       myRaytraceGeometry.Box().CornerMin().cwiseAbs().maxComp(),
226       myRaytraceGeometry.Box().CornerMax().cwiseAbs().maxComp());
227
228     const BVH_Vec3f aSize = myRaytraceGeometry.Box().Size();
229
230     myRaytraceSceneEpsilon = Max (1.0e-6f, 1.0e-4f * aSize.Modulus());
231
232     return uploadRaytraceData (theGlContext);
233   }
234
235   if (myRaytraceParameters.GlobalIllumination)
236   {
237     Standard_Boolean toRestart =
238       aNonRaytraceIDs.size() != myNonRaytraceStructureIDs.size();
239
240     for (std::set<Standard_Integer>::iterator anID = aNonRaytraceIDs.begin(); anID != aNonRaytraceIDs.end() && !toRestart; ++anID)
241     {
242       if (myNonRaytraceStructureIDs.find (*anID) == myNonRaytraceStructureIDs.end())
243       {
244         toRestart = Standard_True;
245       }
246     }
247
248     if (toRestart)
249     {
250       myAccumFrames = 0;
251     }
252
253     myNonRaytraceStructureIDs = aNonRaytraceIDs;
254   }
255
256   return Standard_True;
257 }
258
259 // =======================================================================
260 // function : toUpdateStructure
261 // purpose  : Checks to see if the structure is modified
262 // =======================================================================
263 Standard_Boolean OpenGl_View::toUpdateStructure (const OpenGl_Structure* theStructure)
264 {
265   if (!theStructure->IsRaytracable())
266   {
267     if (theStructure->ModificationState() > 0)
268     {
269       theStructure->ResetModificationState();
270
271       return Standard_True; // ray-trace element was removed - need to rebuild
272     }
273
274     return Standard_False; // did not contain ray-trace elements
275   }
276
277   std::map<const OpenGl_Structure*, StructState>::iterator aStructState = myStructureStates.find (theStructure);
278
279   if (aStructState == myStructureStates.end() || aStructState->second.StructureState != theStructure->ModificationState())
280   {
281     return Standard_True;
282   }
283   else if (theStructure->InstancedStructure() != NULL)
284   {
285     return aStructState->second.InstancedState != theStructure->InstancedStructure()->ModificationState();
286   }
287
288   return Standard_False;
289 }
290
291 // =======================================================================
292 // function : buildTextureTransform
293 // purpose  : Constructs texture transformation matrix
294 // =======================================================================
295 void buildTextureTransform (const Handle(Graphic3d_TextureParams)& theParams, BVH_Mat4f& theMatrix)
296 {
297   theMatrix.InitIdentity();
298   if (theParams.IsNull())
299   {
300     return;
301   }
302
303   // Apply scaling
304   const Graphic3d_Vec2& aScale = theParams->Scale();
305
306   theMatrix.ChangeValue (0, 0) *= aScale.x();
307   theMatrix.ChangeValue (1, 0) *= aScale.x();
308   theMatrix.ChangeValue (2, 0) *= aScale.x();
309   theMatrix.ChangeValue (3, 0) *= aScale.x();
310
311   theMatrix.ChangeValue (0, 1) *= aScale.y();
312   theMatrix.ChangeValue (1, 1) *= aScale.y();
313   theMatrix.ChangeValue (2, 1) *= aScale.y();
314   theMatrix.ChangeValue (3, 1) *= aScale.y();
315
316   // Apply translation
317   const Graphic3d_Vec2 aTrans = -theParams->Translation();
318
319   theMatrix.ChangeValue (0, 3) = theMatrix.GetValue (0, 0) * aTrans.x() +
320                                  theMatrix.GetValue (0, 1) * aTrans.y();
321
322   theMatrix.ChangeValue (1, 3) = theMatrix.GetValue (1, 0) * aTrans.x() +
323                                  theMatrix.GetValue (1, 1) * aTrans.y();
324
325   theMatrix.ChangeValue (2, 3) = theMatrix.GetValue (2, 0) * aTrans.x() +
326                                  theMatrix.GetValue (2, 1) * aTrans.y();
327
328   // Apply rotation
329   const Standard_ShortReal aSin = std::sin (
330     -theParams->Rotation() * static_cast<Standard_ShortReal> (M_PI / 180.0));
331   const Standard_ShortReal aCos = std::cos (
332     -theParams->Rotation() * static_cast<Standard_ShortReal> (M_PI / 180.0));
333
334   BVH_Mat4f aRotationMat;
335   aRotationMat.SetValue (0, 0,  aCos);
336   aRotationMat.SetValue (1, 1,  aCos);
337   aRotationMat.SetValue (0, 1, -aSin);
338   aRotationMat.SetValue (1, 0,  aSin);
339
340   theMatrix = theMatrix * aRotationMat;
341 }
342
343 // =======================================================================
344 // function : convertMaterial
345 // purpose  : Creates ray-tracing material properties
346 // =======================================================================
347 OpenGl_RaytraceMaterial OpenGl_View::convertMaterial (const OpenGl_Aspects* theAspect,
348                                                       const Handle(OpenGl_Context)& theGlContext)
349 {
350   OpenGl_RaytraceMaterial theMaterial;
351
352   const Graphic3d_MaterialAspect& aSrcMat = theAspect->Aspect()->FrontMaterial();
353   const OpenGl_Vec3& aMatCol  = theAspect->Aspect()->InteriorColor();
354   const bool         isPhysic = aSrcMat.MaterialType (Graphic3d_MATERIAL_PHYSIC);
355   const float        aShine   = 128.0f * float(aSrcMat.Shininess());
356
357   // ambient component
358   if (aSrcMat.ReflectionMode (Graphic3d_TOR_AMBIENT))
359   {
360     const OpenGl_Vec3& aSrcAmb = isPhysic ? aSrcMat.AmbientColor() : aMatCol;
361     theMaterial.Ambient = BVH_Vec4f (aSrcAmb * (float )aSrcMat.Ambient(),  1.0f);
362   }
363   else
364   {
365     theMaterial.Ambient = THE_BLACK_COLOR;
366   }
367
368   // diffusion component
369   if (aSrcMat.ReflectionMode (Graphic3d_TOR_DIFFUSE))
370   {
371     const OpenGl_Vec3& aSrcDif = isPhysic ? aSrcMat.DiffuseColor() : aMatCol;
372     theMaterial.Diffuse = BVH_Vec4f (aSrcDif * (float )aSrcMat.Diffuse(), -1.0f); // -1 is no texture
373   }
374   else
375   {
376     theMaterial.Diffuse = BVH_Vec4f (THE_BLACK_COLOR.rgb(), -1.0f);
377   }
378
379   // specular component
380   if (aSrcMat.ReflectionMode (Graphic3d_TOR_SPECULAR))
381   {
382     const OpenGl_Vec3& aSrcSpe  = aSrcMat.SpecularColor();
383     const OpenGl_Vec3& aSrcSpe2 = isPhysic ? aSrcSpe : THE_WHITE_COLOR.rgb();
384     theMaterial.Specular = BVH_Vec4f (aSrcSpe2 * (float )aSrcMat.Specular(), aShine);
385
386     const Standard_ShortReal aMaxRefl = Max (theMaterial.Diffuse.x() + theMaterial.Specular.x(),
387                                         Max (theMaterial.Diffuse.y() + theMaterial.Specular.y(),
388                                              theMaterial.Diffuse.z() + theMaterial.Specular.z()));
389
390     const Standard_ShortReal aReflectionScale = 0.75f / aMaxRefl;
391
392     // ignore isPhysic here
393     theMaterial.Reflection = BVH_Vec4f (aSrcSpe * (float )aSrcMat.Specular() * aReflectionScale, 0.0f);
394   }
395   else
396   {
397     theMaterial.Specular = BVH_Vec4f (THE_BLACK_COLOR.rgb(), aShine);
398   }
399
400   // emission component
401   if (aSrcMat.ReflectionMode (Graphic3d_TOR_EMISSION))
402   {
403     const OpenGl_Vec3& aSrcEms = isPhysic ? aSrcMat.EmissiveColor() : aMatCol;
404     theMaterial.Emission = BVH_Vec4f (aSrcEms * (float )aSrcMat.Emissive(), 1.0f);
405   }
406   else
407   {
408     theMaterial.Emission = THE_BLACK_COLOR;
409   }
410
411   const float anIndex = (float )aSrcMat.RefractionIndex();
412   theMaterial.Transparency = BVH_Vec4f (aSrcMat.Alpha(), aSrcMat.Transparency(),
413                                         anIndex == 0 ? 1.0f : anIndex,
414                                         anIndex == 0 ? 1.0f : 1.0f / anIndex);
415
416   // Serialize physically-based material properties
417   const Graphic3d_BSDF& aBSDF = aSrcMat.BSDF();
418
419   theMaterial.BSDF.Kc = aBSDF.Kc;
420   theMaterial.BSDF.Ks = aBSDF.Ks;
421   theMaterial.BSDF.Kd = BVH_Vec4f (aBSDF.Kd, -1.f); // no texture
422   theMaterial.BSDF.Kt = BVH_Vec4f (aBSDF.Kt,  0.f);
423   theMaterial.BSDF.Le = BVH_Vec4f (aBSDF.Le,  0.f);
424
425   theMaterial.BSDF.Absorption = aBSDF.Absorption;
426
427   theMaterial.BSDF.FresnelCoat = aBSDF.FresnelCoat.Serialize ();
428   theMaterial.BSDF.FresnelBase = aBSDF.FresnelBase.Serialize ();
429
430   // Handle material textures
431   if (!theAspect->Aspect()->ToMapTexture())
432   {
433     return theMaterial;
434   }
435
436   const Handle(OpenGl_TextureSet)& aTextureSet = theAspect->TextureSet (theGlContext);
437   if (aTextureSet.IsNull()
438    || aTextureSet->IsEmpty()
439    || aTextureSet->First().IsNull())
440   {
441     return theMaterial;
442   }
443
444   if (theGlContext->HasRayTracingTextures())
445   {
446     const Handle(OpenGl_Texture)& aTexture = aTextureSet->First();
447     buildTextureTransform (aTexture->Sampler()->Parameters(), theMaterial.TextureTransform);
448
449     // write texture ID to diffuse w-component
450     theMaterial.Diffuse.w() = theMaterial.BSDF.Kd.w() = static_cast<Standard_ShortReal> (myRaytraceGeometry.AddTexture (aTexture));
451   }
452   else if (!myIsRaytraceWarnTextures)
453   {
454     const TCollection_ExtendedString aWarnMessage =
455       "Warning: texturing in Ray-Trace requires GL_ARB_bindless_texture extension which is missing. "
456       "Please try to update graphics card driver. At the moment textures will be ignored.";
457
458     theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION,
459       GL_DEBUG_TYPE_PORTABILITY, 0, GL_DEBUG_SEVERITY_HIGH, aWarnMessage);
460
461     myIsRaytraceWarnTextures = Standard_True;
462   }
463
464   return theMaterial;
465 }
466
467 // =======================================================================
468 // function : addRaytraceStructure
469 // purpose  : Adds OpenGL structure to ray-traced scene geometry
470 // =======================================================================
471 Standard_Boolean OpenGl_View::addRaytraceStructure (const OpenGl_Structure*       theStructure,
472                                                     const Handle(OpenGl_Context)& theGlContext)
473 {
474   if (!theStructure->IsVisible())
475   {
476     myStructureStates[theStructure] = StructState (theStructure);
477
478     return Standard_True;
479   }
480
481   // Get structure material
482   OpenGl_RaytraceMaterial aDefaultMaterial;
483   Standard_Boolean aResult = addRaytraceGroups (theStructure, aDefaultMaterial, theStructure->Transformation(), theGlContext);
484
485   // Process all connected OpenGL structures
486   const OpenGl_Structure* anInstanced = theStructure->InstancedStructure();
487
488   if (anInstanced != NULL && anInstanced->IsRaytracable())
489   {
490     aResult &= addRaytraceGroups (anInstanced, aDefaultMaterial, theStructure->Transformation(), theGlContext);
491   }
492
493   myStructureStates[theStructure] = StructState (theStructure);
494
495   return aResult;
496 }
497
498 // =======================================================================
499 // function : addRaytraceGroups
500 // purpose  : Adds OpenGL groups to ray-traced scene geometry
501 // =======================================================================
502 Standard_Boolean OpenGl_View::addRaytraceGroups (const OpenGl_Structure*        theStructure,
503                                                  const OpenGl_RaytraceMaterial& theStructMat,
504                                                  const Handle(Geom_Transformation)& theTrsf,
505                                                  const Handle(OpenGl_Context)&  theGlContext)
506 {
507   OpenGl_Mat4 aMat4;
508   for (OpenGl_Structure::GroupIterator aGroupIter (theStructure->Groups()); aGroupIter.More(); aGroupIter.Next())
509   {
510     // Get group material
511     OpenGl_RaytraceMaterial aGroupMaterial;
512     if (aGroupIter.Value()->GlAspects() != NULL)
513     {
514       aGroupMaterial = convertMaterial (aGroupIter.Value()->GlAspects(), theGlContext);
515     }
516
517     Standard_Integer aMatID = static_cast<Standard_Integer> (myRaytraceGeometry.Materials.size());
518
519     // Use group material if available, otherwise use structure material
520     myRaytraceGeometry.Materials.push_back (aGroupIter.Value()->GlAspects() != NULL ? aGroupMaterial : theStructMat);
521
522     // Add OpenGL elements from group (extract primitives arrays and aspects)
523     for (const OpenGl_ElementNode* aNode = aGroupIter.Value()->FirstNode(); aNode != NULL; aNode = aNode->next)
524     {
525       OpenGl_Aspects* anAspect = dynamic_cast<OpenGl_Aspects*> (aNode->elem);
526
527       if (anAspect != NULL)
528       {
529         aMatID = static_cast<Standard_Integer> (myRaytraceGeometry.Materials.size());
530
531         OpenGl_RaytraceMaterial aMaterial = convertMaterial (anAspect, theGlContext);
532
533         myRaytraceGeometry.Materials.push_back (aMaterial);
534       }
535       else
536       {
537         OpenGl_PrimitiveArray* aPrimArray = dynamic_cast<OpenGl_PrimitiveArray*> (aNode->elem);
538
539         if (aPrimArray != NULL)
540         {
541           std::map<Standard_Size, OpenGl_TriangleSet*>::iterator aSetIter = myArrayToTrianglesMap.find (aPrimArray->GetUID());
542
543           if (aSetIter != myArrayToTrianglesMap.end())
544           {
545             OpenGl_TriangleSet* aSet = aSetIter->second;
546             opencascade::handle<BVH_Transform<Standard_ShortReal, 4> > aTransform = new BVH_Transform<Standard_ShortReal, 4>();
547             if (!theTrsf.IsNull())
548             {
549               theTrsf->Trsf().GetMat4 (aMat4);
550               aTransform->SetTransform (aMat4);
551             }
552
553             aSet->SetProperties (aTransform);
554             if (aSet->MaterialIndex() != OpenGl_TriangleSet::INVALID_MATERIAL && aSet->MaterialIndex() != aMatID)
555             {
556               aSet->SetMaterialIndex (aMatID);
557             }
558           }
559           else
560           {
561             if (Handle(OpenGl_TriangleSet) aSet = addRaytracePrimitiveArray (aPrimArray, aMatID, 0))
562             {
563               opencascade::handle<BVH_Transform<Standard_ShortReal, 4> > aTransform = new BVH_Transform<Standard_ShortReal, 4>();
564               if (!theTrsf.IsNull())
565               {
566                 theTrsf->Trsf().GetMat4 (aMat4);
567                 aTransform->SetTransform (aMat4);
568               }
569
570               aSet->SetProperties (aTransform);
571               myRaytraceGeometry.Objects().Append (aSet);
572             }
573           }
574         }
575       }
576     }
577   }
578
579   return Standard_True;
580 }
581
582 // =======================================================================
583 // function : addRaytracePrimitiveArray
584 // purpose  : Adds OpenGL primitive array to ray-traced scene geometry
585 // =======================================================================
586 Handle(OpenGl_TriangleSet) OpenGl_View::addRaytracePrimitiveArray (const OpenGl_PrimitiveArray* theArray,
587                                                                    const Standard_Integer       theMaterial,
588                                                                    const OpenGl_Mat4*           theTransform)
589 {
590   const Handle(Graphic3d_BoundBuffer)& aBounds   = theArray->Bounds();
591   const Handle(Graphic3d_IndexBuffer)& anIndices = theArray->Indices();
592   const Handle(Graphic3d_Buffer)&      anAttribs = theArray->Attributes();
593
594   if (theArray->DrawMode() < GL_TRIANGLES
595   #ifndef GL_ES_VERSION_2_0
596    || theArray->DrawMode() > GL_POLYGON
597   #else
598    || theArray->DrawMode() > GL_TRIANGLE_FAN
599   #endif
600    || anAttribs.IsNull())
601   {
602     return Handle(OpenGl_TriangleSet)();
603   }
604
605   OpenGl_Mat4 aNormalMatrix;
606   if (theTransform != NULL)
607   {
608     Standard_ASSERT_RETURN (theTransform->Inverted (aNormalMatrix),
609       "Error: Failed to compute normal transformation matrix", NULL);
610
611     aNormalMatrix.Transpose();
612   }
613
614   Handle(OpenGl_TriangleSet) aSet = new OpenGl_TriangleSet (theArray->GetUID(), myRaytraceBVHBuilder);
615   {
616     aSet->Vertices.reserve (anAttribs->NbElements);
617     aSet->Normals.reserve  (anAttribs->NbElements);
618     aSet->TexCrds.reserve  (anAttribs->NbElements);
619
620     const size_t aVertFrom = aSet->Vertices.size();
621
622     Standard_Integer anAttribIndex = 0;
623     Standard_Size anAttribStride = 0;
624     if (const Standard_Byte* aPosData = anAttribs->AttributeData (Graphic3d_TOA_POS, anAttribIndex, anAttribStride))
625     {
626       const Graphic3d_Attribute& anAttrib = anAttribs->Attribute (anAttribIndex);
627       if (anAttrib.DataType == Graphic3d_TOD_VEC2
628        || anAttrib.DataType == Graphic3d_TOD_VEC3
629        || anAttrib.DataType == Graphic3d_TOD_VEC4)
630       {
631         for (Standard_Integer aVertIter = 0; aVertIter < anAttribs->NbElements; ++aVertIter)
632         {
633           const float* aCoords = reinterpret_cast<const float*> (aPosData + anAttribStride * aVertIter);
634           aSet->Vertices.push_back (BVH_Vec3f (aCoords[0], aCoords[1], anAttrib.DataType != Graphic3d_TOD_VEC2 ? aCoords[2] : 0.0f));
635         }
636       }
637     }
638     if (const Standard_Byte* aNormData = anAttribs->AttributeData (Graphic3d_TOA_NORM, anAttribIndex, anAttribStride))
639     {
640       const Graphic3d_Attribute& anAttrib = anAttribs->Attribute (anAttribIndex);
641       if (anAttrib.DataType == Graphic3d_TOD_VEC3
642        || anAttrib.DataType == Graphic3d_TOD_VEC4)
643       {
644         for (Standard_Integer aVertIter = 0; aVertIter < anAttribs->NbElements; ++aVertIter)
645         {
646           aSet->Normals.push_back (*reinterpret_cast<const Graphic3d_Vec3*> (aNormData + anAttribStride * aVertIter));
647         }
648       }
649     }
650     if (const Standard_Byte* aTexData = anAttribs->AttributeData (Graphic3d_TOA_UV, anAttribIndex, anAttribStride))
651     {
652       const Graphic3d_Attribute& anAttrib = anAttribs->Attribute (anAttribIndex);
653       if (anAttrib.DataType == Graphic3d_TOD_VEC2)
654       {
655         for (Standard_Integer aVertIter = 0; aVertIter < anAttribs->NbElements; ++aVertIter)
656         {
657           aSet->TexCrds.push_back (*reinterpret_cast<const Graphic3d_Vec2*> (aTexData + anAttribStride * aVertIter));
658         }
659       }
660     }
661
662     if (aSet->Normals.size() != aSet->Vertices.size())
663     {
664       for (Standard_Integer aVertIter = 0; aVertIter < anAttribs->NbElements; ++aVertIter)
665       {
666         aSet->Normals.push_back (BVH_Vec3f());
667       }
668     }
669
670     if (aSet->TexCrds.size() != aSet->Vertices.size())
671     {
672       for (Standard_Integer aVertIter = 0; aVertIter < anAttribs->NbElements; ++aVertIter)
673       {
674         aSet->TexCrds.push_back (BVH_Vec2f());
675       }
676     }
677
678     if (theTransform != NULL)
679     {
680       for (size_t aVertIter = aVertFrom; aVertIter < aSet->Vertices.size(); ++aVertIter)
681       {
682         BVH_Vec3f& aVertex = aSet->Vertices[aVertIter];
683
684         BVH_Vec4f aTransVertex = *theTransform *
685           BVH_Vec4f (aVertex.x(), aVertex.y(), aVertex.z(), 1.f);
686
687         aVertex = BVH_Vec3f (aTransVertex.x(), aTransVertex.y(), aTransVertex.z());
688       }
689       for (size_t aVertIter = aVertFrom; aVertIter < aSet->Normals.size(); ++aVertIter)
690       {
691         BVH_Vec3f& aNormal = aSet->Normals[aVertIter];
692
693         BVH_Vec4f aTransNormal = aNormalMatrix *
694           BVH_Vec4f (aNormal.x(), aNormal.y(), aNormal.z(), 0.f);
695
696         aNormal = BVH_Vec3f (aTransNormal.x(), aTransNormal.y(), aTransNormal.z());
697       }
698     }
699
700     if (!aBounds.IsNull())
701     {
702       for (Standard_Integer aBound = 0, aBoundStart = 0; aBound < aBounds->NbBounds; ++aBound)
703       {
704         const Standard_Integer aVertNum = aBounds->Bounds[aBound];
705
706         if (!addRaytraceVertexIndices (*aSet, theMaterial, aVertNum, aBoundStart, *theArray))
707         {
708           aSet.Nullify();
709           return Handle(OpenGl_TriangleSet)();
710         }
711
712         aBoundStart += aVertNum;
713       }
714     }
715     else
716     {
717       const Standard_Integer aVertNum = !anIndices.IsNull() ? anIndices->NbElements : anAttribs->NbElements;
718
719       if (!addRaytraceVertexIndices (*aSet, theMaterial, aVertNum, 0, *theArray))
720       {
721         aSet.Nullify();
722         return Handle(OpenGl_TriangleSet)();
723       }
724     }
725   }
726
727   if (aSet->Size() != 0)
728   {
729     aSet->MarkDirty();
730   }
731
732   return aSet;
733 }
734
735 // =======================================================================
736 // function : addRaytraceVertexIndices
737 // purpose  : Adds vertex indices to ray-traced scene geometry
738 // =======================================================================
739 Standard_Boolean OpenGl_View::addRaytraceVertexIndices (OpenGl_TriangleSet&                  theSet,
740                                                         const Standard_Integer               theMatID,
741                                                         const Standard_Integer               theCount,
742                                                         const Standard_Integer               theOffset,
743                                                         const OpenGl_PrimitiveArray&         theArray)
744 {
745   switch (theArray.DrawMode())
746   {
747     case GL_TRIANGLES:      return addRaytraceTriangleArray        (theSet, theMatID, theCount, theOffset, theArray.Indices());
748     case GL_TRIANGLE_FAN:   return addRaytraceTriangleFanArray     (theSet, theMatID, theCount, theOffset, theArray.Indices());
749     case GL_TRIANGLE_STRIP: return addRaytraceTriangleStripArray   (theSet, theMatID, theCount, theOffset, theArray.Indices());
750   #if !defined(GL_ES_VERSION_2_0)
751     case GL_QUAD_STRIP:     return addRaytraceQuadrangleStripArray (theSet, theMatID, theCount, theOffset, theArray.Indices());
752     case GL_QUADS:          return addRaytraceQuadrangleArray      (theSet, theMatID, theCount, theOffset, theArray.Indices());
753     case GL_POLYGON:        return addRaytracePolygonArray         (theSet, theMatID, theCount, theOffset, theArray.Indices());
754   #endif
755   }
756
757   return Standard_False;
758 }
759
760 // =======================================================================
761 // function : addRaytraceTriangleArray
762 // purpose  : Adds OpenGL triangle array to ray-traced scene geometry
763 // =======================================================================
764 Standard_Boolean OpenGl_View::addRaytraceTriangleArray (OpenGl_TriangleSet&                  theSet,
765                                                         const Standard_Integer               theMatID,
766                                                         const Standard_Integer               theCount,
767                                                         const Standard_Integer               theOffset,
768                                                         const Handle(Graphic3d_IndexBuffer)& theIndices)
769 {
770   if (theCount < 3)
771   {
772     return Standard_True;
773   }
774
775   theSet.Elements.reserve (theSet.Elements.size() + theCount / 3);
776
777   if (!theIndices.IsNull())
778   {
779     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 2; aVert += 3)
780     {
781       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (aVert + 0),
782                                             theIndices->Index (aVert + 1),
783                                             theIndices->Index (aVert + 2),
784                                             theMatID));
785     }
786   }
787   else
788   {
789     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 2; aVert += 3)
790     {
791       theSet.Elements.push_back (BVH_Vec4i (aVert + 0, aVert + 1, aVert + 2, theMatID));
792     }
793   }
794
795   return Standard_True;
796 }
797
798 // =======================================================================
799 // function : addRaytraceTriangleFanArray
800 // purpose  : Adds OpenGL triangle fan array to ray-traced scene geometry
801 // =======================================================================
802 Standard_Boolean OpenGl_View::addRaytraceTriangleFanArray (OpenGl_TriangleSet&                  theSet,
803                                                            const Standard_Integer               theMatID,
804                                                            const Standard_Integer               theCount,
805                                                            const Standard_Integer               theOffset,
806                                                            const Handle(Graphic3d_IndexBuffer)& theIndices)
807 {
808   if (theCount < 3)
809   {
810     return Standard_True;
811   }
812
813   theSet.Elements.reserve (theSet.Elements.size() + theCount - 2);
814
815   if (!theIndices.IsNull())
816   {
817     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 2; ++aVert)
818     {
819       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (theOffset),
820                                             theIndices->Index (aVert + 1),
821                                             theIndices->Index (aVert + 2),
822                                             theMatID));
823     }
824   }
825   else
826   {
827     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 2; ++aVert)
828     {
829       theSet.Elements.push_back (BVH_Vec4i (theOffset,
830                                             aVert + 1,
831                                             aVert + 2,
832                                             theMatID));
833     }
834   }
835
836   return Standard_True;
837 }
838
839 // =======================================================================
840 // function : addRaytraceTriangleStripArray
841 // purpose  : Adds OpenGL triangle strip array to ray-traced scene geometry
842 // =======================================================================
843 Standard_Boolean OpenGl_View::addRaytraceTriangleStripArray (OpenGl_TriangleSet&                  theSet,
844                                                              const Standard_Integer               theMatID,
845                                                              const Standard_Integer               theCount,
846                                                              const Standard_Integer               theOffset,
847                                                              const Handle(Graphic3d_IndexBuffer)& theIndices)
848 {
849   if (theCount < 3)
850   {
851     return Standard_True;
852   }
853
854   theSet.Elements.reserve (theSet.Elements.size() + theCount - 2);
855
856   if (!theIndices.IsNull())
857   {
858     for (Standard_Integer aVert = theOffset, aCW = 0; aVert < theOffset + theCount - 2; ++aVert, aCW = (aCW + 1) % 2)
859     {
860       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (aVert + (aCW ? 1 : 0)),
861                                             theIndices->Index (aVert + (aCW ? 0 : 1)),
862                                             theIndices->Index (aVert + 2),
863                                             theMatID));
864     }
865   }
866   else
867   {
868     for (Standard_Integer aVert = theOffset, aCW = 0; aVert < theOffset + theCount - 2; ++aVert, aCW = (aCW + 1) % 2)
869     {
870       theSet.Elements.push_back (BVH_Vec4i (aVert + (aCW ? 1 : 0),
871                                             aVert + (aCW ? 0 : 1),
872                                             aVert + 2,
873                                             theMatID));
874     }
875   }
876
877   return Standard_True;
878 }
879
880 // =======================================================================
881 // function : addRaytraceQuadrangleArray
882 // purpose  : Adds OpenGL quad array to ray-traced scene geometry
883 // =======================================================================
884 Standard_Boolean OpenGl_View::addRaytraceQuadrangleArray (OpenGl_TriangleSet&                  theSet,
885                                                           const Standard_Integer               theMatID,
886                                                           const Standard_Integer               theCount,
887                                                           const Standard_Integer               theOffset,
888                                                           const Handle(Graphic3d_IndexBuffer)& theIndices)
889 {
890   if (theCount < 4)
891   {
892     return Standard_True;
893   }
894
895   theSet.Elements.reserve (theSet.Elements.size() + theCount / 2);
896
897   if (!theIndices.IsNull())
898   {
899     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 3; aVert += 4)
900     {
901       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (aVert + 0),
902                                             theIndices->Index (aVert + 1),
903                                             theIndices->Index (aVert + 2),
904                                             theMatID));
905       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (aVert + 0),
906                                             theIndices->Index (aVert + 2),
907                                             theIndices->Index (aVert + 3),
908                                             theMatID));
909     }
910   }
911   else
912   {
913     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 3; aVert += 4)
914     {
915       theSet.Elements.push_back (BVH_Vec4i (aVert + 0, aVert + 1, aVert + 2,
916                                             theMatID));
917       theSet.Elements.push_back (BVH_Vec4i (aVert + 0, aVert + 2, aVert + 3,
918                                             theMatID));
919     }
920   }
921
922   return Standard_True;
923 }
924
925 // =======================================================================
926 // function : addRaytraceQuadrangleStripArray
927 // purpose  : Adds OpenGL quad strip array to ray-traced scene geometry
928 // =======================================================================
929 Standard_Boolean OpenGl_View::addRaytraceQuadrangleStripArray (OpenGl_TriangleSet&                  theSet,
930                                                                const Standard_Integer               theMatID,
931                                                                const Standard_Integer               theCount,
932                                                                const Standard_Integer               theOffset,
933                                                                const Handle(Graphic3d_IndexBuffer)& theIndices)
934 {
935   if (theCount < 4)
936   {
937     return Standard_True;
938   }
939
940   theSet.Elements.reserve (theSet.Elements.size() + 2 * theCount - 6);
941
942   if (!theIndices.IsNull())
943   {
944     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 3; aVert += 2)
945     {
946       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (aVert + 0),
947                                             theIndices->Index (aVert + 1),
948                                             theIndices->Index (aVert + 2),
949                                             theMatID));
950
951       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (aVert + 1),
952                                             theIndices->Index (aVert + 3),
953                                             theIndices->Index (aVert + 2),
954                                             theMatID));
955     }
956   }
957   else
958   {
959     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 3; aVert += 2)
960     {
961       theSet.Elements.push_back (BVH_Vec4i (aVert + 0,
962                                             aVert + 1,
963                                             aVert + 2,
964                                             theMatID));
965
966       theSet.Elements.push_back (BVH_Vec4i (aVert + 1,
967                                             aVert + 3,
968                                             aVert + 2,
969                                             theMatID));
970     }
971   }
972
973   return Standard_True;
974 }
975
976 // =======================================================================
977 // function : addRaytracePolygonArray
978 // purpose  : Adds OpenGL polygon array to ray-traced scene geometry
979 // =======================================================================
980 Standard_Boolean OpenGl_View::addRaytracePolygonArray (OpenGl_TriangleSet&                  theSet,
981                                                        const Standard_Integer               theMatID,
982                                                        const Standard_Integer               theCount,
983                                                        const Standard_Integer               theOffset,
984                                                        const Handle(Graphic3d_IndexBuffer)& theIndices)
985 {
986   if (theCount < 3)
987   {
988     return Standard_True;
989   }
990
991   theSet.Elements.reserve (theSet.Elements.size() + theCount - 2);
992
993   if (!theIndices.IsNull())
994   {
995     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 2; ++aVert)
996     {
997       theSet.Elements.push_back (BVH_Vec4i (theIndices->Index (theOffset),
998                                             theIndices->Index (aVert + 1),
999                                             theIndices->Index (aVert + 2),
1000                                             theMatID));
1001     }
1002   }
1003   else
1004   {
1005     for (Standard_Integer aVert = theOffset; aVert < theOffset + theCount - 2; ++aVert)
1006     {
1007       theSet.Elements.push_back (BVH_Vec4i (theOffset,
1008                                             aVert + 1,
1009                                             aVert + 2,
1010                                             theMatID));
1011     }
1012   }
1013
1014   return Standard_True;
1015 }
1016
1017 const TCollection_AsciiString OpenGl_View::ShaderSource::EMPTY_PREFIX;
1018
1019 // =======================================================================
1020 // function : Source
1021 // purpose  : Returns shader source combined with prefix
1022 // =======================================================================
1023 TCollection_AsciiString OpenGl_View::ShaderSource::Source() const
1024 {
1025   const TCollection_AsciiString aVersion = "#version 140";
1026
1027   if (myPrefix.IsEmpty())
1028   {
1029     return aVersion + "\n" + mySource;
1030   }
1031
1032   return aVersion + "\n" + myPrefix + "\n" + mySource;
1033 }
1034
1035 // =======================================================================
1036 // function : LoadFromFiles
1037 // purpose  : Loads shader source from specified files
1038 // =======================================================================
1039 Standard_Boolean OpenGl_View::ShaderSource::LoadFromFiles (const TCollection_AsciiString* theFileNames,
1040                                                            const TCollection_AsciiString& thePrefix)
1041 {
1042   myError.Clear();
1043   mySource.Clear();
1044   myPrefix = thePrefix;
1045
1046   TCollection_AsciiString aMissingFiles;
1047   for (Standard_Integer anIndex = 0; !theFileNames[anIndex].IsEmpty(); ++anIndex)
1048   {
1049     OSD_File aFile (theFileNames[anIndex]);
1050     if (aFile.Exists())
1051     {
1052       aFile.Open (OSD_ReadOnly, OSD_Protection());
1053     }
1054     if (!aFile.IsOpen())
1055     {
1056       if (!aMissingFiles.IsEmpty())
1057       {
1058         aMissingFiles += ", ";
1059       }
1060       aMissingFiles += TCollection_AsciiString("'") + theFileNames[anIndex] + "'";
1061       continue;
1062     }
1063     else if (!aMissingFiles.IsEmpty())
1064     {
1065       aFile.Close();
1066       continue;
1067     }
1068
1069     TCollection_AsciiString aSource;
1070     aFile.Read (aSource, (Standard_Integer) aFile.Size());
1071     if (!aSource.IsEmpty())
1072     {
1073       mySource += TCollection_AsciiString ("\n") + aSource;
1074     }
1075     aFile.Close();
1076   }
1077
1078   if (!aMissingFiles.IsEmpty())
1079   {
1080     myError = TCollection_AsciiString("Shader files ") + aMissingFiles + " are missing or inaccessible";
1081     return Standard_False;
1082   }
1083   return Standard_True;
1084 }
1085
1086 // =======================================================================
1087 // function : LoadFromStrings
1088 // purpose  :
1089 // =======================================================================
1090 Standard_Boolean OpenGl_View::ShaderSource::LoadFromStrings (const TCollection_AsciiString* theStrings,
1091                                                              const TCollection_AsciiString& thePrefix)
1092 {
1093   myError.Clear();
1094   mySource.Clear();
1095   myPrefix = thePrefix;
1096
1097   for (Standard_Integer anIndex = 0; !theStrings[anIndex].IsEmpty(); ++anIndex)
1098   {
1099     TCollection_AsciiString aSource = theStrings[anIndex];
1100     if (!aSource.IsEmpty())
1101     {
1102       mySource += TCollection_AsciiString ("\n") + aSource;
1103     }
1104   }
1105   return Standard_True;
1106 }
1107
1108 // =======================================================================
1109 // function : generateShaderPrefix
1110 // purpose  : Generates shader prefix based on current ray-tracing options
1111 // =======================================================================
1112 TCollection_AsciiString OpenGl_View::generateShaderPrefix (const Handle(OpenGl_Context)& theGlContext) const
1113 {
1114   TCollection_AsciiString aPrefixString =
1115     TCollection_AsciiString ("#define STACK_SIZE ") + TCollection_AsciiString (myRaytraceParameters.StackSize) + "\n" +
1116     TCollection_AsciiString ("#define NB_BOUNCES ") + TCollection_AsciiString (myRaytraceParameters.NbBounces);
1117
1118   if (myRaytraceParameters.TransparentShadows)
1119   {
1120     aPrefixString += TCollection_AsciiString ("\n#define TRANSPARENT_SHADOWS");
1121   }
1122
1123   // If OpenGL driver supports bindless textures and texturing
1124   // is actually used, activate texturing in ray-tracing mode
1125   if (myRaytraceParameters.UseBindlessTextures && theGlContext->arbTexBindless != NULL)
1126   {
1127     aPrefixString += TCollection_AsciiString ("\n#define USE_TEXTURES") +
1128       TCollection_AsciiString ("\n#define MAX_TEX_NUMBER ") + TCollection_AsciiString (OpenGl_RaytraceGeometry::MAX_TEX_NUMBER);
1129   }
1130
1131   if (myRaytraceParameters.GlobalIllumination) // path tracing activated
1132   {
1133     aPrefixString += TCollection_AsciiString ("\n#define PATH_TRACING");
1134
1135     if (myRaytraceParameters.AdaptiveScreenSampling) // adaptive screen sampling requested
1136     {
1137       if (theGlContext->IsGlGreaterEqual (4, 4))
1138       {
1139         aPrefixString += TCollection_AsciiString ("\n#define ADAPTIVE_SAMPLING");
1140         if (myRaytraceParameters.AdaptiveScreenSamplingAtomic
1141          && theGlContext->CheckExtension ("GL_NV_shader_atomic_float"))
1142         {
1143           aPrefixString += TCollection_AsciiString ("\n#define ADAPTIVE_SAMPLING_ATOMIC");
1144         }
1145       }
1146     }
1147
1148     if (myRaytraceParameters.TwoSidedBsdfModels) // two-sided BSDFs requested
1149     {
1150       aPrefixString += TCollection_AsciiString ("\n#define TWO_SIDED_BXDF");
1151     }
1152
1153     switch (myRaytraceParameters.ToneMappingMethod)
1154     {
1155       case Graphic3d_ToneMappingMethod_Disabled:
1156         break;
1157       case Graphic3d_ToneMappingMethod_Filmic:
1158         aPrefixString += TCollection_AsciiString ("\n#define TONE_MAPPING_FILMIC");
1159         break;
1160     }
1161   }
1162
1163   if (myRaytraceParameters.DepthOfField)
1164   {
1165     aPrefixString += TCollection_AsciiString("\n#define DEPTH_OF_FIELD");
1166   }
1167
1168   return aPrefixString;
1169 }
1170
1171 // =======================================================================
1172 // function : safeFailBack
1173 // purpose  : Performs safe exit when shaders initialization fails
1174 // =======================================================================
1175 Standard_Boolean OpenGl_View::safeFailBack (const TCollection_ExtendedString& theMessage,
1176                                             const Handle(OpenGl_Context)&     theGlContext)
1177 {
1178   theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION,
1179     GL_DEBUG_TYPE_ERROR, 0, GL_DEBUG_SEVERITY_HIGH, theMessage);
1180
1181   myRaytraceInitStatus = OpenGl_RT_FAIL;
1182
1183   releaseRaytraceResources (theGlContext);
1184
1185   return Standard_False;
1186 }
1187
1188 // =======================================================================
1189 // function : initShader
1190 // purpose  : Creates new shader object with specified source
1191 // =======================================================================
1192 Handle(OpenGl_ShaderObject) OpenGl_View::initShader (const GLenum                  theType,
1193                                                      const ShaderSource&           theSource,
1194                                                      const Handle(OpenGl_Context)& theGlContext)
1195 {
1196   Handle(OpenGl_ShaderObject) aShader = new OpenGl_ShaderObject (theType);
1197   if (!aShader->Create (theGlContext))
1198   {
1199     theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_ERROR, 0, GL_DEBUG_SEVERITY_HIGH,
1200                                TCollection_ExtendedString ("Error: Failed to create ") +
1201                                (theType == GL_VERTEX_SHADER ? "vertex" : "fragment") + " shader object");
1202     aShader->Release (theGlContext.get());
1203     return Handle(OpenGl_ShaderObject)();
1204   }
1205
1206   if (!aShader->LoadAndCompile (theGlContext, "", theSource.Source()))
1207   {
1208     aShader->Release (theGlContext.get());
1209     return Handle(OpenGl_ShaderObject)();
1210   }
1211   return aShader;
1212 }
1213
1214 // =======================================================================
1215 // function : initProgram
1216 // purpose  : Creates GLSL program from the given shader objects
1217 // =======================================================================
1218 Handle(OpenGl_ShaderProgram) OpenGl_View::initProgram (const Handle(OpenGl_Context)&      theGlContext,
1219                                                        const Handle(OpenGl_ShaderObject)& theVertShader,
1220                                                        const Handle(OpenGl_ShaderObject)& theFragShader,
1221                                                        const TCollection_AsciiString& theName)
1222 {
1223   const TCollection_AsciiString anId = TCollection_AsciiString("occt_rt_") + theName;
1224   Handle(OpenGl_ShaderProgram) aProgram = new OpenGl_ShaderProgram(Handle(Graphic3d_ShaderProgram)(), anId);
1225
1226   if (!aProgram->Create (theGlContext))
1227   {
1228     theVertShader->Release (theGlContext.operator->());
1229
1230     theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION,
1231       GL_DEBUG_TYPE_ERROR, 0, GL_DEBUG_SEVERITY_HIGH, "Failed to create shader program");
1232
1233     return Handle(OpenGl_ShaderProgram)();
1234   }
1235
1236   if (!aProgram->AttachShader (theGlContext, theVertShader)
1237    || !aProgram->AttachShader (theGlContext, theFragShader))
1238   {
1239     theVertShader->Release (theGlContext.operator->());
1240
1241     theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION,
1242       GL_DEBUG_TYPE_ERROR, 0, GL_DEBUG_SEVERITY_HIGH, "Failed to attach shader objects");
1243
1244     return Handle(OpenGl_ShaderProgram)();
1245   }
1246
1247   aProgram->SetAttributeName (theGlContext, Graphic3d_TOA_POS, "occVertex");
1248
1249   TCollection_AsciiString aLinkLog;
1250
1251   if (!aProgram->Link (theGlContext))
1252   {
1253     aProgram->FetchInfoLog (theGlContext, aLinkLog);
1254
1255     const TCollection_ExtendedString aMessage = TCollection_ExtendedString (
1256       "Failed to link shader program:\n") + aLinkLog;
1257
1258     theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION,
1259       GL_DEBUG_TYPE_ERROR, 0, GL_DEBUG_SEVERITY_HIGH, aMessage);
1260
1261     return Handle(OpenGl_ShaderProgram)();
1262   }
1263   else if (theGlContext->caps->glslWarnings)
1264   {
1265     aProgram->FetchInfoLog (theGlContext, aLinkLog);
1266     if (!aLinkLog.IsEmpty() && !aLinkLog.IsEqual ("No errors.\n"))
1267     {
1268       const TCollection_ExtendedString aMessage = TCollection_ExtendedString (
1269         "Shader program was linked with following warnings:\n") + aLinkLog;
1270
1271       theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION,
1272         GL_DEBUG_TYPE_PORTABILITY, 0, GL_DEBUG_SEVERITY_LOW, aMessage);
1273     }
1274   }
1275
1276   return aProgram;
1277 }
1278
1279 // =======================================================================
1280 // function : initRaytraceResources
1281 // purpose  : Initializes OpenGL/GLSL shader programs
1282 // =======================================================================
1283 Standard_Boolean OpenGl_View::initRaytraceResources (const Standard_Integer theSizeX,
1284                                                      const Standard_Integer theSizeY,
1285                                                      const Handle(OpenGl_Context)& theGlContext)
1286 {
1287   if (myRaytraceInitStatus == OpenGl_RT_FAIL)
1288   {
1289     return Standard_False;
1290   }
1291
1292   Standard_Boolean aToRebuildShaders = Standard_False;
1293
1294   if (myRenderParams.RebuildRayTracingShaders) // requires complete re-initialization
1295   {
1296     myRaytraceInitStatus = OpenGl_RT_NONE;
1297     releaseRaytraceResources (theGlContext, Standard_True);
1298     myRenderParams.RebuildRayTracingShaders = Standard_False; // clear rebuilding flag
1299   }
1300
1301   if (myRaytraceInitStatus == OpenGl_RT_INIT)
1302   {
1303     if (!myIsRaytraceDataValid)
1304     {
1305       return Standard_True;
1306     }
1307
1308     const Standard_Integer aRequiredStackSize =
1309       myRaytraceGeometry.TopLevelTreeDepth() + myRaytraceGeometry.BotLevelTreeDepth();
1310
1311     if (myRaytraceParameters.StackSize < aRequiredStackSize)
1312     {
1313       myRaytraceParameters.StackSize = Max (aRequiredStackSize, THE_DEFAULT_STACK_SIZE);
1314
1315       aToRebuildShaders = Standard_True;
1316     }
1317     else
1318     {
1319       if (aRequiredStackSize < myRaytraceParameters.StackSize)
1320       {
1321         if (myRaytraceParameters.StackSize > THE_DEFAULT_STACK_SIZE)
1322         {
1323           myRaytraceParameters.StackSize = Max (aRequiredStackSize, THE_DEFAULT_STACK_SIZE);
1324           aToRebuildShaders = Standard_True;
1325         }
1326       }
1327     }
1328
1329     if (myRenderParams.RaytracingDepth             != myRaytraceParameters.NbBounces
1330      || myRenderParams.IsTransparentShadowEnabled  != myRaytraceParameters.TransparentShadows
1331      || myRenderParams.IsGlobalIlluminationEnabled != myRaytraceParameters.GlobalIllumination
1332      || myRenderParams.TwoSidedBsdfModels          != myRaytraceParameters.TwoSidedBsdfModels
1333      || myRaytraceGeometry.HasTextures()           != myRaytraceParameters.UseBindlessTextures)
1334     {
1335       myRaytraceParameters.NbBounces           = myRenderParams.RaytracingDepth;
1336       myRaytraceParameters.TransparentShadows  = myRenderParams.IsTransparentShadowEnabled;
1337       myRaytraceParameters.GlobalIllumination  = myRenderParams.IsGlobalIlluminationEnabled;
1338       myRaytraceParameters.TwoSidedBsdfModels  = myRenderParams.TwoSidedBsdfModels;
1339       myRaytraceParameters.UseBindlessTextures = myRaytraceGeometry.HasTextures();
1340       aToRebuildShaders = Standard_True;
1341     }
1342
1343     if (myRenderParams.AdaptiveScreenSampling       != myRaytraceParameters.AdaptiveScreenSampling
1344      || myRenderParams.AdaptiveScreenSamplingAtomic != myRaytraceParameters.AdaptiveScreenSamplingAtomic)
1345     {
1346       myRaytraceParameters.AdaptiveScreenSampling       = myRenderParams.AdaptiveScreenSampling;
1347       myRaytraceParameters.AdaptiveScreenSamplingAtomic = myRenderParams.AdaptiveScreenSamplingAtomic;
1348       if (myRenderParams.AdaptiveScreenSampling) // adaptive sampling was requested
1349       {
1350         if (!theGlContext->HasRayTracingAdaptiveSampling())
1351         {
1352           // disable the feature if it is not supported
1353           myRaytraceParameters.AdaptiveScreenSampling = myRenderParams.AdaptiveScreenSampling = Standard_False;
1354           theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_PORTABILITY, 0, GL_DEBUG_SEVERITY_LOW,
1355                                      "Adaptive sampling is not supported (OpenGL 4.4 is missing)");
1356         }
1357         else if (myRaytraceParameters.AdaptiveScreenSamplingAtomic
1358              && !theGlContext->HasRayTracingAdaptiveSamplingAtomic())
1359         {
1360           // disable the feature if it is not supported
1361           myRaytraceParameters.AdaptiveScreenSamplingAtomic = myRenderParams.AdaptiveScreenSamplingAtomic = Standard_False;
1362           theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_PORTABILITY, 0, GL_DEBUG_SEVERITY_LOW,
1363                                      "Atomic adaptive sampling is not supported (GL_NV_shader_atomic_float is missing)");
1364         }
1365       }
1366
1367       aToRebuildShaders = Standard_True;
1368     }
1369     myTileSampler.SetSize (myRenderParams, myRaytraceParameters.AdaptiveScreenSampling ? Graphic3d_Vec2i (theSizeX, theSizeY) : Graphic3d_Vec2i (0, 0));
1370
1371     const bool toEnableDof = !myCamera->IsOrthographic() && myRaytraceParameters.GlobalIllumination;
1372     if (myRaytraceParameters.DepthOfField != toEnableDof)
1373     {
1374       myRaytraceParameters.DepthOfField = toEnableDof;
1375       aToRebuildShaders = Standard_True;
1376     }
1377
1378     if (myRenderParams.ToneMappingMethod != myRaytraceParameters.ToneMappingMethod)
1379     {
1380       myRaytraceParameters.ToneMappingMethod = myRenderParams.ToneMappingMethod;
1381       aToRebuildShaders = true;
1382     }
1383
1384     if (aToRebuildShaders)
1385     {
1386       // Reject accumulated frames
1387       myAccumFrames = 0;
1388
1389       // Environment map should be updated
1390       myToUpdateEnvironmentMap = Standard_True;
1391
1392       const TCollection_AsciiString aPrefixString = generateShaderPrefix (theGlContext);
1393
1394 #ifdef RAY_TRACE_PRINT_INFO
1395       std::cout << "GLSL prefix string:" << std::endl << aPrefixString << std::endl;
1396 #endif
1397
1398       myRaytraceShaderSource.SetPrefix (aPrefixString);
1399       myPostFSAAShaderSource.SetPrefix (aPrefixString);
1400       myOutImageShaderSource.SetPrefix (aPrefixString);
1401
1402       if (!myRaytraceShader->LoadAndCompile (theGlContext, myRaytraceProgram->ResourceId(), myRaytraceShaderSource.Source())
1403        || !myPostFSAAShader->LoadAndCompile (theGlContext, myPostFSAAProgram->ResourceId(), myPostFSAAShaderSource.Source())
1404        || !myOutImageShader->LoadAndCompile (theGlContext, myOutImageProgram->ResourceId(), myOutImageShaderSource.Source()))
1405       {
1406         return safeFailBack ("Failed to compile ray-tracing fragment shaders", theGlContext);
1407       }
1408
1409       myRaytraceProgram->SetAttributeName (theGlContext, Graphic3d_TOA_POS, "occVertex");
1410       myPostFSAAProgram->SetAttributeName (theGlContext, Graphic3d_TOA_POS, "occVertex");
1411       myOutImageProgram->SetAttributeName (theGlContext, Graphic3d_TOA_POS, "occVertex");
1412
1413       if (!myRaytraceProgram->Link (theGlContext)
1414        || !myPostFSAAProgram->Link (theGlContext)
1415        || !myOutImageProgram->Link (theGlContext))
1416       {
1417         return safeFailBack ("Failed to initialize vertex attributes for ray-tracing program", theGlContext);
1418       }
1419     }
1420   }
1421
1422   if (myRaytraceInitStatus == OpenGl_RT_NONE)
1423   {
1424     myAccumFrames = 0; // accumulation should be restarted
1425
1426     if (!theGlContext->IsGlGreaterEqual (3, 1))
1427     {
1428       return safeFailBack ("Ray-tracing requires OpenGL 3.1 and higher", theGlContext);
1429     }
1430     else if (!theGlContext->arbTboRGB32)
1431     {
1432       return safeFailBack ("Ray-tracing requires OpenGL 4.0+ or GL_ARB_texture_buffer_object_rgb32 extension", theGlContext);
1433     }
1434     else if (!theGlContext->arbFBOBlit)
1435     {
1436       return safeFailBack ("Ray-tracing requires EXT_framebuffer_blit extension", theGlContext);
1437     }
1438
1439     myRaytraceParameters.NbBounces = myRenderParams.RaytracingDepth;
1440
1441     const TCollection_AsciiString aShaderFolder = Graphic3d_ShaderProgram::ShadersFolder();
1442     if (myIsRaytraceDataValid)
1443     {
1444       myRaytraceParameters.StackSize = Max (THE_DEFAULT_STACK_SIZE,
1445         myRaytraceGeometry.TopLevelTreeDepth() + myRaytraceGeometry.BotLevelTreeDepth());
1446     }
1447
1448     const TCollection_AsciiString aPrefixString  = generateShaderPrefix (theGlContext);
1449
1450 #ifdef RAY_TRACE_PRINT_INFO
1451     std::cout << "GLSL prefix string:" << std::endl << aPrefixString << std::endl;
1452 #endif
1453
1454     ShaderSource aBasicVertShaderSrc;
1455     {
1456       if (!aShaderFolder.IsEmpty())
1457       {
1458         const TCollection_AsciiString aFiles[] = { aShaderFolder + "/RaytraceBase.vs", "" };
1459         if (!aBasicVertShaderSrc.LoadFromFiles (aFiles))
1460         {
1461           return safeFailBack (aBasicVertShaderSrc.ErrorDescription(), theGlContext);
1462         }
1463       }
1464       else
1465       {
1466         const TCollection_AsciiString aSrcShaders[] = { Shaders_RaytraceBase_vs, "" };
1467         aBasicVertShaderSrc.LoadFromStrings (aSrcShaders);
1468       }
1469     }
1470
1471     {
1472       if (!aShaderFolder.IsEmpty())
1473       {
1474         const TCollection_AsciiString aFiles[] = { aShaderFolder + "/RaytraceBase.fs",
1475                                                    aShaderFolder + "/PathtraceBase.fs",
1476                                                    aShaderFolder + "/RaytraceRender.fs",
1477                                                    "" };
1478         if (!myRaytraceShaderSource.LoadFromFiles (aFiles, aPrefixString))
1479         {
1480           return safeFailBack (myRaytraceShaderSource.ErrorDescription(), theGlContext);
1481         }
1482       }
1483       else
1484       {
1485         const TCollection_AsciiString aSrcShaders[] = { Shaders_RaytraceBase_fs,
1486                                                         Shaders_PathtraceBase_fs,
1487                                                         Shaders_RaytraceRender_fs,
1488                                                         "" };
1489         myRaytraceShaderSource.LoadFromStrings (aSrcShaders, aPrefixString);
1490       }
1491
1492       Handle(OpenGl_ShaderObject) aBasicVertShader = initShader (GL_VERTEX_SHADER, aBasicVertShaderSrc, theGlContext);
1493       if (aBasicVertShader.IsNull())
1494       {
1495         return safeFailBack ("Failed to initialize ray-trace vertex shader", theGlContext);
1496       }
1497
1498       myRaytraceShader = initShader (GL_FRAGMENT_SHADER, myRaytraceShaderSource, theGlContext);
1499       if (myRaytraceShader.IsNull())
1500       {
1501         aBasicVertShader->Release (theGlContext.operator->());
1502         return safeFailBack ("Failed to initialize ray-trace fragment shader", theGlContext);
1503       }
1504
1505       myRaytraceProgram = initProgram (theGlContext, aBasicVertShader, myRaytraceShader, "main");
1506       if (myRaytraceProgram.IsNull())
1507       {
1508         return safeFailBack ("Failed to initialize ray-trace shader program", theGlContext);
1509       }
1510     }
1511
1512     {
1513       if (!aShaderFolder.IsEmpty())
1514       {
1515         const TCollection_AsciiString aFiles[] = { aShaderFolder + "/RaytraceBase.fs", aShaderFolder + "/RaytraceSmooth.fs", "" };
1516         if (!myPostFSAAShaderSource.LoadFromFiles (aFiles, aPrefixString))
1517         {
1518           return safeFailBack (myPostFSAAShaderSource.ErrorDescription(), theGlContext);
1519         }
1520       }
1521       else
1522       {
1523         const TCollection_AsciiString aSrcShaders[] = { Shaders_RaytraceBase_fs, Shaders_RaytraceSmooth_fs, "" };
1524         myPostFSAAShaderSource.LoadFromStrings (aSrcShaders, aPrefixString);
1525       }
1526
1527       Handle(OpenGl_ShaderObject) aBasicVertShader = initShader (GL_VERTEX_SHADER, aBasicVertShaderSrc, theGlContext);
1528       if (aBasicVertShader.IsNull())
1529       {
1530         return safeFailBack ("Failed to initialize FSAA vertex shader", theGlContext);
1531       }
1532
1533       myPostFSAAShader = initShader (GL_FRAGMENT_SHADER, myPostFSAAShaderSource, theGlContext);
1534       if (myPostFSAAShader.IsNull())
1535       {
1536         aBasicVertShader->Release (theGlContext.operator->());
1537         return safeFailBack ("Failed to initialize FSAA fragment shader", theGlContext);
1538       }
1539
1540       myPostFSAAProgram = initProgram (theGlContext, aBasicVertShader, myPostFSAAShader, "fsaa");
1541       if (myPostFSAAProgram.IsNull())
1542       {
1543         return safeFailBack ("Failed to initialize FSAA shader program", theGlContext);
1544       }
1545     }
1546
1547     {
1548       if (!aShaderFolder.IsEmpty())
1549       {
1550         const TCollection_AsciiString aFiles[] = { aShaderFolder + "/Display.fs", "" };
1551         if (!myOutImageShaderSource.LoadFromFiles (aFiles, aPrefixString))
1552         {
1553           return safeFailBack (myOutImageShaderSource.ErrorDescription(), theGlContext);
1554         }
1555       }
1556       else
1557       {
1558         const TCollection_AsciiString aSrcShaders[] = { Shaders_Display_fs, "" };
1559         myOutImageShaderSource.LoadFromStrings (aSrcShaders, aPrefixString);
1560       }
1561
1562       Handle(OpenGl_ShaderObject) aBasicVertShader = initShader (GL_VERTEX_SHADER, aBasicVertShaderSrc, theGlContext);
1563       if (aBasicVertShader.IsNull())
1564       {
1565         return safeFailBack ("Failed to set vertex shader source", theGlContext);
1566       }
1567
1568       myOutImageShader = initShader (GL_FRAGMENT_SHADER, myOutImageShaderSource, theGlContext);
1569       if (myOutImageShader.IsNull())
1570       {
1571         aBasicVertShader->Release (theGlContext.operator->());
1572         return safeFailBack ("Failed to set display fragment shader source", theGlContext);
1573       }
1574
1575       myOutImageProgram = initProgram (theGlContext, aBasicVertShader, myOutImageShader, "out");
1576       if (myOutImageProgram.IsNull())
1577       {
1578         return safeFailBack ("Failed to initialize display shader program", theGlContext);
1579       }
1580     }
1581   }
1582
1583   if (myRaytraceInitStatus == OpenGl_RT_NONE || aToRebuildShaders)
1584   {
1585     for (Standard_Integer anIndex = 0; anIndex < 2; ++anIndex)
1586     {
1587       Handle(OpenGl_ShaderProgram)& aShaderProgram =
1588         (anIndex == 0) ? myRaytraceProgram : myPostFSAAProgram;
1589
1590       theGlContext->BindProgram (aShaderProgram);
1591
1592       aShaderProgram->SetSampler (theGlContext,
1593         "uSceneMinPointTexture", OpenGl_RT_SceneMinPointTexture);
1594       aShaderProgram->SetSampler (theGlContext,
1595         "uSceneMaxPointTexture", OpenGl_RT_SceneMaxPointTexture);
1596       aShaderProgram->SetSampler (theGlContext,
1597         "uSceneNodeInfoTexture", OpenGl_RT_SceneNodeInfoTexture);
1598       aShaderProgram->SetSampler (theGlContext,
1599         "uGeometryVertexTexture", OpenGl_RT_GeometryVertexTexture);
1600       aShaderProgram->SetSampler (theGlContext,
1601         "uGeometryNormalTexture", OpenGl_RT_GeometryNormalTexture);
1602       aShaderProgram->SetSampler (theGlContext,
1603         "uGeometryTexCrdTexture", OpenGl_RT_GeometryTexCrdTexture);
1604       aShaderProgram->SetSampler (theGlContext,
1605         "uGeometryTriangTexture", OpenGl_RT_GeometryTriangTexture);
1606       aShaderProgram->SetSampler (theGlContext, 
1607         "uSceneTransformTexture", OpenGl_RT_SceneTransformTexture);
1608       aShaderProgram->SetSampler (theGlContext,
1609         "uEnvironmentMapTexture", OpenGl_RT_EnvironmentMapTexture);
1610       aShaderProgram->SetSampler (theGlContext,
1611         "uRaytraceMaterialTexture", OpenGl_RT_RaytraceMaterialTexture);
1612       aShaderProgram->SetSampler (theGlContext,
1613         "uRaytraceLightSrcTexture", OpenGl_RT_RaytraceLightSrcTexture);
1614
1615       if (anIndex == 1)
1616       {
1617         aShaderProgram->SetSampler (theGlContext,
1618           "uFSAAInputTexture", OpenGl_RT_FsaaInputTexture);
1619       }
1620       else
1621       {
1622         aShaderProgram->SetSampler (theGlContext,
1623           "uAccumTexture", OpenGl_RT_PrevAccumTexture);
1624       }
1625
1626       myUniformLocations[anIndex][OpenGl_RT_aPosition] =
1627         aShaderProgram->GetAttributeLocation (theGlContext, "occVertex");
1628
1629       myUniformLocations[anIndex][OpenGl_RT_uOriginLB] =
1630         aShaderProgram->GetUniformLocation (theGlContext, "uOriginLB");
1631       myUniformLocations[anIndex][OpenGl_RT_uOriginRB] =
1632         aShaderProgram->GetUniformLocation (theGlContext, "uOriginRB");
1633       myUniformLocations[anIndex][OpenGl_RT_uOriginLT] =
1634         aShaderProgram->GetUniformLocation (theGlContext, "uOriginLT");
1635       myUniformLocations[anIndex][OpenGl_RT_uOriginRT] =
1636         aShaderProgram->GetUniformLocation (theGlContext, "uOriginRT");
1637       myUniformLocations[anIndex][OpenGl_RT_uDirectLB] =
1638         aShaderProgram->GetUniformLocation (theGlContext, "uDirectLB");
1639       myUniformLocations[anIndex][OpenGl_RT_uDirectRB] =
1640         aShaderProgram->GetUniformLocation (theGlContext, "uDirectRB");
1641       myUniformLocations[anIndex][OpenGl_RT_uDirectLT] =
1642         aShaderProgram->GetUniformLocation (theGlContext, "uDirectLT");
1643       myUniformLocations[anIndex][OpenGl_RT_uDirectRT] =
1644         aShaderProgram->GetUniformLocation (theGlContext, "uDirectRT");
1645       myUniformLocations[anIndex][OpenGl_RT_uViewPrMat] =
1646         aShaderProgram->GetUniformLocation (theGlContext, "uViewMat");
1647       myUniformLocations[anIndex][OpenGl_RT_uUnviewMat] =
1648         aShaderProgram->GetUniformLocation (theGlContext, "uUnviewMat");
1649
1650       myUniformLocations[anIndex][OpenGl_RT_uSceneRad] =
1651         aShaderProgram->GetUniformLocation (theGlContext, "uSceneRadius");
1652       myUniformLocations[anIndex][OpenGl_RT_uSceneEps] =
1653         aShaderProgram->GetUniformLocation (theGlContext, "uSceneEpsilon");
1654       myUniformLocations[anIndex][OpenGl_RT_uLightCount] =
1655         aShaderProgram->GetUniformLocation (theGlContext, "uLightCount");
1656       myUniformLocations[anIndex][OpenGl_RT_uLightAmbnt] =
1657         aShaderProgram->GetUniformLocation (theGlContext, "uGlobalAmbient");
1658
1659       myUniformLocations[anIndex][OpenGl_RT_uOffsetX] =
1660         aShaderProgram->GetUniformLocation (theGlContext, "uOffsetX");
1661       myUniformLocations[anIndex][OpenGl_RT_uOffsetY] =
1662         aShaderProgram->GetUniformLocation (theGlContext, "uOffsetY");
1663       myUniformLocations[anIndex][OpenGl_RT_uSamples] =
1664         aShaderProgram->GetUniformLocation (theGlContext, "uSamples");
1665
1666       myUniformLocations[anIndex][OpenGl_RT_uTexSamplersArray] =
1667         aShaderProgram->GetUniformLocation (theGlContext, "uTextureSamplers");
1668
1669       myUniformLocations[anIndex][OpenGl_RT_uShadowsEnabled] =
1670         aShaderProgram->GetUniformLocation (theGlContext, "uShadowsEnabled");
1671       myUniformLocations[anIndex][OpenGl_RT_uReflectEnabled] =
1672         aShaderProgram->GetUniformLocation (theGlContext, "uReflectEnabled");
1673       myUniformLocations[anIndex][OpenGl_RT_uSphereMapEnabled] =
1674         aShaderProgram->GetUniformLocation (theGlContext, "uSphereMapEnabled");
1675       myUniformLocations[anIndex][OpenGl_RT_uSphereMapForBack] =
1676         aShaderProgram->GetUniformLocation (theGlContext, "uSphereMapForBack");
1677       myUniformLocations[anIndex][OpenGl_RT_uBlockedRngEnabled] =
1678         aShaderProgram->GetUniformLocation (theGlContext, "uBlockedRngEnabled");
1679
1680       myUniformLocations[anIndex][OpenGl_RT_uWinSizeX] =
1681         aShaderProgram->GetUniformLocation (theGlContext, "uWinSizeX");
1682       myUniformLocations[anIndex][OpenGl_RT_uWinSizeY] =
1683         aShaderProgram->GetUniformLocation (theGlContext, "uWinSizeY");
1684
1685       myUniformLocations[anIndex][OpenGl_RT_uAccumSamples] =
1686         aShaderProgram->GetUniformLocation (theGlContext, "uAccumSamples");
1687       myUniformLocations[anIndex][OpenGl_RT_uFrameRndSeed] =
1688         aShaderProgram->GetUniformLocation (theGlContext, "uFrameRndSeed");
1689
1690       myUniformLocations[anIndex][OpenGl_RT_uRenderImage] =
1691         aShaderProgram->GetUniformLocation (theGlContext, "uRenderImage");
1692       myUniformLocations[anIndex][OpenGl_RT_uTilesImage] =
1693         aShaderProgram->GetUniformLocation (theGlContext, "uTilesImage");
1694       myUniformLocations[anIndex][OpenGl_RT_uOffsetImage] =
1695         aShaderProgram->GetUniformLocation (theGlContext, "uOffsetImage");
1696       myUniformLocations[anIndex][OpenGl_RT_uTileSize] =
1697         aShaderProgram->GetUniformLocation (theGlContext, "uTileSize");
1698       myUniformLocations[anIndex][OpenGl_RT_uVarianceScaleFactor] =
1699         aShaderProgram->GetUniformLocation (theGlContext, "uVarianceScaleFactor");
1700
1701       myUniformLocations[anIndex][OpenGl_RT_uBackColorTop] =
1702         aShaderProgram->GetUniformLocation (theGlContext, "uBackColorTop");
1703       myUniformLocations[anIndex][OpenGl_RT_uBackColorBot] =
1704         aShaderProgram->GetUniformLocation (theGlContext, "uBackColorBot");
1705
1706       myUniformLocations[anIndex][OpenGl_RT_uMaxRadiance] =
1707         aShaderProgram->GetUniformLocation (theGlContext, "uMaxRadiance");
1708     }
1709
1710     theGlContext->BindProgram (myOutImageProgram);
1711
1712     myOutImageProgram->SetSampler (theGlContext,
1713       "uInputTexture", OpenGl_RT_PrevAccumTexture);
1714
1715     myOutImageProgram->SetSampler (theGlContext,
1716       "uDepthTexture", OpenGl_RT_RaytraceDepthTexture);
1717
1718     theGlContext->BindProgram (NULL);
1719   }
1720
1721   if (myRaytraceInitStatus != OpenGl_RT_NONE)
1722   {
1723     return myRaytraceInitStatus == OpenGl_RT_INIT;
1724   }
1725
1726   const GLfloat aVertices[] = { -1.f, -1.f,  0.f,
1727                                 -1.f,  1.f,  0.f,
1728                                  1.f,  1.f,  0.f,
1729                                  1.f,  1.f,  0.f,
1730                                  1.f, -1.f,  0.f,
1731                                 -1.f, -1.f,  0.f };
1732
1733   myRaytraceScreenQuad.Init (theGlContext, 3, 6, aVertices);
1734
1735   myRaytraceInitStatus = OpenGl_RT_INIT; // initialized in normal way
1736
1737   return Standard_True;
1738 }
1739
1740 // =======================================================================
1741 // function : nullifyResource
1742 // purpose  : Releases OpenGL resource
1743 // =======================================================================
1744 template <class T>
1745 inline void nullifyResource (const Handle(OpenGl_Context)& theGlContext, Handle(T)& theResource)
1746 {
1747   if (!theResource.IsNull())
1748   {
1749     theResource->Release (theGlContext.get());
1750     theResource.Nullify();
1751   }
1752 }
1753
1754 // =======================================================================
1755 // function : releaseRaytraceResources
1756 // purpose  : Releases OpenGL/GLSL shader programs
1757 // =======================================================================
1758 void OpenGl_View::releaseRaytraceResources (const Handle(OpenGl_Context)& theGlContext, const Standard_Boolean theToRebuild)
1759 {
1760   // release shader resources
1761   nullifyResource (theGlContext, myRaytraceShader);
1762   nullifyResource (theGlContext, myPostFSAAShader);
1763
1764   nullifyResource (theGlContext, myRaytraceProgram);
1765   nullifyResource (theGlContext, myPostFSAAProgram);
1766   nullifyResource (theGlContext, myOutImageProgram);
1767
1768   if (!theToRebuild) // complete release
1769   {
1770     myRaytraceFBO1[0]->Release (theGlContext.get());
1771     myRaytraceFBO1[1]->Release (theGlContext.get());
1772     myRaytraceFBO2[0]->Release (theGlContext.get());
1773     myRaytraceFBO2[1]->Release (theGlContext.get());
1774
1775     nullifyResource (theGlContext, myRaytraceOutputTexture[0]);
1776     nullifyResource (theGlContext, myRaytraceOutputTexture[1]);
1777
1778     nullifyResource (theGlContext, myRaytraceTileOffsetsTexture[0]);
1779     nullifyResource (theGlContext, myRaytraceTileOffsetsTexture[1]);
1780     nullifyResource (theGlContext, myRaytraceVisualErrorTexture[0]);
1781     nullifyResource (theGlContext, myRaytraceVisualErrorTexture[1]);
1782     nullifyResource (theGlContext, myRaytraceTileSamplesTexture[0]);
1783     nullifyResource (theGlContext, myRaytraceTileSamplesTexture[1]);
1784
1785     nullifyResource (theGlContext, mySceneNodeInfoTexture);
1786     nullifyResource (theGlContext, mySceneMinPointTexture);
1787     nullifyResource (theGlContext, mySceneMaxPointTexture);
1788
1789     nullifyResource (theGlContext, myGeometryVertexTexture);
1790     nullifyResource (theGlContext, myGeometryNormalTexture);
1791     nullifyResource (theGlContext, myGeometryTexCrdTexture);
1792     nullifyResource (theGlContext, myGeometryTriangTexture);
1793     nullifyResource (theGlContext, mySceneTransformTexture);
1794
1795     nullifyResource (theGlContext, myRaytraceLightSrcTexture);
1796     nullifyResource (theGlContext, myRaytraceMaterialTexture);
1797
1798     myRaytraceGeometry.ReleaseResources (theGlContext);
1799
1800     if (myRaytraceScreenQuad.IsValid ())
1801     {
1802       myRaytraceScreenQuad.Release (theGlContext.get());
1803     }
1804   }
1805 }
1806
1807 // =======================================================================
1808 // function : updateRaytraceBuffers
1809 // purpose  : Updates auxiliary OpenGL frame buffers.
1810 // =======================================================================
1811 Standard_Boolean OpenGl_View::updateRaytraceBuffers (const Standard_Integer        theSizeX,
1812                                                      const Standard_Integer        theSizeY,
1813                                                      const Handle(OpenGl_Context)& theGlContext)
1814 {
1815   // Auxiliary buffers are not used
1816   if (!myRaytraceParameters.GlobalIllumination && !myRenderParams.IsAntialiasingEnabled)
1817   {
1818     myRaytraceFBO1[0]->Release (theGlContext.operator->());
1819     myRaytraceFBO2[0]->Release (theGlContext.operator->());
1820     myRaytraceFBO1[1]->Release (theGlContext.operator->());
1821     myRaytraceFBO2[1]->Release (theGlContext.operator->());
1822
1823     return Standard_True;
1824   }
1825
1826   if (myRaytraceParameters.AdaptiveScreenSampling)
1827   {
1828     Graphic3d_Vec2i aMaxViewport = myTileSampler.OffsetTilesViewportMax().cwiseMax (Graphic3d_Vec2i (theSizeX, theSizeY));
1829     myRaytraceFBO1[0]->InitLazy (theGlContext, aMaxViewport.x(), aMaxViewport.y(), GL_RGBA32F, myFboDepthFormat);
1830     myRaytraceFBO2[0]->InitLazy (theGlContext, aMaxViewport.x(), aMaxViewport.y(), GL_RGBA32F, myFboDepthFormat);
1831     if (myRaytraceFBO1[1]->IsValid()) // second FBO not needed
1832     {
1833       myRaytraceFBO1[1]->Release (theGlContext.operator->());
1834       myRaytraceFBO2[1]->Release (theGlContext.operator->());
1835     }
1836   }
1837
1838   for (int aViewIter = 0; aViewIter < 2; ++aViewIter)
1839   {
1840     if (myRaytraceTileOffsetsTexture[aViewIter].IsNull())
1841     {
1842       myRaytraceOutputTexture[aViewIter] = new OpenGl_Texture();
1843       myRaytraceVisualErrorTexture[aViewIter] = new OpenGl_Texture();
1844       myRaytraceTileSamplesTexture[aViewIter] = new OpenGl_Texture();
1845       myRaytraceTileOffsetsTexture[aViewIter] = new OpenGl_Texture();
1846     }
1847
1848     if (aViewIter == 1
1849      && myCamera->ProjectionType() != Graphic3d_Camera::Projection_Stereo)
1850     {
1851       myRaytraceFBO1[1]->Release (theGlContext.operator->());
1852       myRaytraceFBO2[1]->Release (theGlContext.operator->());
1853       myRaytraceOutputTexture[1]->Release (theGlContext.operator->());
1854       myRaytraceVisualErrorTexture[1]->Release (theGlContext.operator->());
1855       myRaytraceTileOffsetsTexture[1]->Release (theGlContext.operator->());
1856       continue;
1857     }
1858
1859     if (myRaytraceParameters.AdaptiveScreenSampling)
1860     {
1861       if (myRaytraceOutputTexture[aViewIter]->SizeX() / 3 == theSizeX
1862        && myRaytraceOutputTexture[aViewIter]->SizeY() / 2 == theSizeY
1863        && myRaytraceVisualErrorTexture[aViewIter]->SizeX() == myTileSampler.NbTilesX()
1864        && myRaytraceVisualErrorTexture[aViewIter]->SizeY() == myTileSampler.NbTilesY())
1865       {
1866         if (myRaytraceParameters.AdaptiveScreenSamplingAtomic)
1867         {
1868           continue; // offsets texture is dynamically resized
1869         }
1870         else if (myRaytraceTileSamplesTexture[aViewIter]->SizeX() == myTileSampler.NbTilesX()
1871               && myRaytraceTileSamplesTexture[aViewIter]->SizeY() == myTileSampler.NbTilesY())
1872         {
1873           continue;
1874         }
1875       }
1876
1877       myAccumFrames = 0;
1878
1879       // Due to limitations of OpenGL image load-store extension
1880       // atomic operations are supported only for single-channel
1881       // images, so we define GL_R32F image. It is used as array
1882       // of 6D floating point vectors:
1883       // 0 - R color channel
1884       // 1 - G color channel
1885       // 2 - B color channel
1886       // 3 - hit time transformed into OpenGL NDC space
1887       // 4 - luminance accumulated for odd samples only
1888       myRaytraceOutputTexture[aViewIter]->InitRectangle (theGlContext, theSizeX * 3, theSizeY * 2, OpenGl_TextureFormat::Create<GLfloat, 1>());
1889
1890       // workaround for some NVIDIA drivers
1891       myRaytraceVisualErrorTexture[aViewIter]->Release (theGlContext.operator->());
1892       myRaytraceTileSamplesTexture[aViewIter]->Release (theGlContext.operator->());
1893       myRaytraceVisualErrorTexture[aViewIter]->Init (theGlContext, GL_R32I, GL_RED_INTEGER, GL_INT,
1894                                                      myTileSampler.NbTilesX(), myTileSampler.NbTilesY(), Graphic3d_TOT_2D);
1895       if (!myRaytraceParameters.AdaptiveScreenSamplingAtomic)
1896       {
1897         myRaytraceTileSamplesTexture[aViewIter]->Init (theGlContext, GL_R32I, GL_RED_INTEGER, GL_INT,
1898                                                        myTileSampler.NbTilesX(), myTileSampler.NbTilesY(), Graphic3d_TOT_2D);
1899       }
1900     }
1901     else // non-adaptive mode
1902     {
1903       if (myRaytraceFBO1[aViewIter]->GetSizeX() != theSizeX
1904        || myRaytraceFBO1[aViewIter]->GetSizeY() != theSizeY)
1905       {
1906         myAccumFrames = 0; // accumulation should be restarted
1907       }
1908
1909       myRaytraceFBO1[aViewIter]->InitLazy (theGlContext, theSizeX, theSizeY, GL_RGBA32F, myFboDepthFormat);
1910       myRaytraceFBO2[aViewIter]->InitLazy (theGlContext, theSizeX, theSizeY, GL_RGBA32F, myFboDepthFormat);
1911     }
1912   }
1913   return Standard_True;
1914 }
1915
1916 // =======================================================================
1917 // function : updateCamera
1918 // purpose  : Generates viewing rays for corners of screen quad
1919 // =======================================================================
1920 void OpenGl_View::updateCamera (const OpenGl_Mat4& theOrientation,
1921                                 const OpenGl_Mat4& theViewMapping,
1922                                 OpenGl_Vec3*       theOrigins,
1923                                 OpenGl_Vec3*       theDirects,
1924                                 OpenGl_Mat4&       theViewPr,
1925                                 OpenGl_Mat4&       theUnview)
1926 {
1927   // compute view-projection matrix
1928   theViewPr = theViewMapping * theOrientation;
1929
1930   // compute inverse view-projection matrix
1931   theViewPr.Inverted (theUnview);
1932
1933   Standard_Integer aOriginIndex = 0;
1934   Standard_Integer aDirectIndex = 0;
1935
1936   for (Standard_Integer aY = -1; aY <= 1; aY += 2)
1937   {
1938     for (Standard_Integer aX = -1; aX <= 1; aX += 2)
1939     {
1940       OpenGl_Vec4 aOrigin (GLfloat(aX),
1941                            GLfloat(aY),
1942                            -1.0f,
1943                            1.0f);
1944
1945       aOrigin = theUnview * aOrigin;
1946
1947       aOrigin.x() = aOrigin.x() / aOrigin.w();
1948       aOrigin.y() = aOrigin.y() / aOrigin.w();
1949       aOrigin.z() = aOrigin.z() / aOrigin.w();
1950
1951       OpenGl_Vec4 aDirect (GLfloat(aX),
1952                            GLfloat(aY),
1953                            1.0f,
1954                            1.0f);
1955
1956       aDirect = theUnview * aDirect;
1957
1958       aDirect.x() = aDirect.x() / aDirect.w();
1959       aDirect.y() = aDirect.y() / aDirect.w();
1960       aDirect.z() = aDirect.z() / aDirect.w();
1961
1962       aDirect = aDirect - aOrigin;
1963
1964       theOrigins[aOriginIndex++] = OpenGl_Vec3 (static_cast<GLfloat> (aOrigin.x()),
1965                                                 static_cast<GLfloat> (aOrigin.y()),
1966                                                 static_cast<GLfloat> (aOrigin.z()));
1967
1968       theDirects[aDirectIndex++] = OpenGl_Vec3 (static_cast<GLfloat> (aDirect.x()),
1969                                                 static_cast<GLfloat> (aDirect.y()),
1970                                                 static_cast<GLfloat> (aDirect.z()));
1971     }
1972   }
1973 }
1974
1975 // =======================================================================
1976 // function : updatePerspCameraPT
1977 // purpose  : Generates viewing rays (path tracing, perspective camera)
1978 // =======================================================================
1979 void OpenGl_View::updatePerspCameraPT (const OpenGl_Mat4&           theOrientation,
1980                                        const OpenGl_Mat4&           theViewMapping,
1981                                        Graphic3d_Camera::Projection theProjection,
1982                                        OpenGl_Mat4&                 theViewPr,
1983                                        OpenGl_Mat4&                 theUnview,
1984                                        const int                    theWinSizeX,
1985                                        const int                    theWinSizeY)
1986 {
1987   // compute view-projection matrix
1988   theViewPr = theViewMapping * theOrientation;
1989
1990   // compute inverse view-projection matrix
1991   theViewPr.Inverted(theUnview);
1992   
1993   // get camera stereo params
1994   float anIOD = myCamera->GetIODType() == Graphic3d_Camera::IODType_Relative
1995     ? static_cast<float> (myCamera->IOD() * myCamera->Distance())
1996     : static_cast<float> (myCamera->IOD());
1997
1998   float aZFocus = myCamera->ZFocusType() == Graphic3d_Camera::FocusType_Relative
1999     ? static_cast<float> (myCamera->ZFocus() * myCamera->Distance())
2000     : static_cast<float> (myCamera->ZFocus());
2001
2002   // get camera view vectors
2003   const gp_Pnt anOrig = myCamera->Eye();
2004
2005   myEyeOrig = OpenGl_Vec3 (static_cast<float> (anOrig.X()),
2006                            static_cast<float> (anOrig.Y()),
2007                            static_cast<float> (anOrig.Z()));
2008
2009   const gp_Dir aView = myCamera->Direction();
2010
2011   OpenGl_Vec3 anEyeViewMono = OpenGl_Vec3 (static_cast<float> (aView.X()),
2012                                            static_cast<float> (aView.Y()),
2013                                            static_cast<float> (aView.Z()));
2014
2015   const gp_Dir anUp = myCamera->Up();
2016
2017   myEyeVert = OpenGl_Vec3 (static_cast<float> (anUp.X()),
2018                            static_cast<float> (anUp.Y()),
2019                            static_cast<float> (anUp.Z()));
2020
2021   myEyeSide = OpenGl_Vec3::Cross (anEyeViewMono, myEyeVert);
2022
2023   const double aScaleY = tan (myCamera->FOVy() / 360 * M_PI);
2024   const double aScaleX = theWinSizeX * aScaleY / theWinSizeY;
2025  
2026   myEyeSize = OpenGl_Vec2 (static_cast<float> (aScaleX),
2027                            static_cast<float> (aScaleY));
2028
2029   if (theProjection == Graphic3d_Camera::Projection_Perspective)
2030   {
2031     myEyeView = anEyeViewMono;
2032   }
2033   else // stereo camera
2034   {
2035     // compute z-focus point
2036     OpenGl_Vec3 aZFocusPoint = myEyeOrig + anEyeViewMono * aZFocus;
2037
2038     // compute stereo camera shift
2039     float aDx = theProjection == Graphic3d_Camera::Projection_MonoRightEye ? 0.5f * anIOD : -0.5f * anIOD;
2040     myEyeOrig += myEyeSide.Normalized() * aDx;
2041
2042     // estimate new camera direction vector and correct its length
2043     myEyeView = (aZFocusPoint - myEyeOrig).Normalized();
2044     myEyeView *= 1.f / anEyeViewMono.Dot (myEyeView);
2045   }
2046 }
2047
2048 // =======================================================================
2049 // function : uploadRaytraceData
2050 // purpose  : Uploads ray-trace data to the GPU
2051 // =======================================================================
2052 Standard_Boolean OpenGl_View::uploadRaytraceData (const Handle(OpenGl_Context)& theGlContext)
2053 {
2054   if (!theGlContext->IsGlGreaterEqual (3, 1))
2055   {
2056 #ifdef RAY_TRACE_PRINT_INFO
2057     std::cout << "Error: OpenGL version is less than 3.1" << std::endl;
2058 #endif
2059     return Standard_False;
2060   }
2061
2062   myAccumFrames = 0; // accumulation should be restarted
2063
2064   /////////////////////////////////////////////////////////////////////////////
2065   // Prepare OpenGL textures
2066
2067   if (theGlContext->arbTexBindless != NULL)
2068   {
2069     // If OpenGL driver supports bindless textures we need
2070     // to get unique 64- bit handles for using on the GPU
2071     if (!myRaytraceGeometry.UpdateTextureHandles (theGlContext))
2072     {
2073 #ifdef RAY_TRACE_PRINT_INFO
2074       std::cout << "Error: Failed to get OpenGL texture handles" << std::endl;
2075 #endif
2076       return Standard_False;
2077     }
2078   }
2079
2080   /////////////////////////////////////////////////////////////////////////////
2081   // Create OpenGL BVH buffers
2082
2083   if (mySceneNodeInfoTexture.IsNull()) // create scene BVH buffers
2084   {
2085     mySceneNodeInfoTexture  = new OpenGl_TextureBufferArb;
2086     mySceneMinPointTexture  = new OpenGl_TextureBufferArb;
2087     mySceneMaxPointTexture  = new OpenGl_TextureBufferArb;
2088     mySceneTransformTexture = new OpenGl_TextureBufferArb;
2089
2090     if (!mySceneNodeInfoTexture->Create  (theGlContext)
2091      || !mySceneMinPointTexture->Create  (theGlContext)
2092      || !mySceneMaxPointTexture->Create  (theGlContext)
2093      || !mySceneTransformTexture->Create (theGlContext))
2094     {
2095 #ifdef RAY_TRACE_PRINT_INFO
2096       std::cout << "Error: Failed to create scene BVH buffers" << std::endl;
2097 #endif
2098       return Standard_False;
2099     }
2100   }
2101
2102   if (myGeometryVertexTexture.IsNull()) // create geometry buffers
2103   {
2104     myGeometryVertexTexture = new OpenGl_TextureBufferArb;
2105     myGeometryNormalTexture = new OpenGl_TextureBufferArb;
2106     myGeometryTexCrdTexture = new OpenGl_TextureBufferArb;
2107     myGeometryTriangTexture = new OpenGl_TextureBufferArb;
2108
2109     if (!myGeometryVertexTexture->Create (theGlContext)
2110      || !myGeometryNormalTexture->Create (theGlContext)
2111      || !myGeometryTexCrdTexture->Create (theGlContext)
2112      || !myGeometryTriangTexture->Create (theGlContext))
2113     {
2114 #ifdef RAY_TRACE_PRINT_INFO
2115       std::cout << "Error: Failed to create buffers for triangulation data" << std::endl;
2116 #endif
2117       return Standard_False;
2118     }
2119   }
2120
2121   if (myRaytraceMaterialTexture.IsNull()) // create material buffer
2122   {
2123     myRaytraceMaterialTexture = new OpenGl_TextureBufferArb;
2124
2125     if (!myRaytraceMaterialTexture->Create (theGlContext))
2126     {
2127 #ifdef RAY_TRACE_PRINT_INFO
2128       std::cout << "Error: Failed to create buffers for material data" << std::endl;
2129 #endif
2130       return Standard_False;
2131     }
2132   }
2133   
2134   /////////////////////////////////////////////////////////////////////////////
2135   // Write transform buffer
2136
2137   BVH_Mat4f* aNodeTransforms = new BVH_Mat4f[myRaytraceGeometry.Size()];
2138
2139   bool aResult = true;
2140
2141   for (Standard_Integer anElemIndex = 0; anElemIndex < myRaytraceGeometry.Size(); ++anElemIndex)
2142   {
2143     OpenGl_TriangleSet* aTriangleSet = dynamic_cast<OpenGl_TriangleSet*> (
2144       myRaytraceGeometry.Objects().ChangeValue (anElemIndex).operator->());
2145
2146     const BVH_Transform<Standard_ShortReal, 4>* aTransform = dynamic_cast<const BVH_Transform<Standard_ShortReal, 4>* > (aTriangleSet->Properties().get());
2147     Standard_ASSERT_RETURN (aTransform != NULL,
2148       "OpenGl_TriangleSet does not contain transform", Standard_False);
2149
2150     aNodeTransforms[anElemIndex] = aTransform->Inversed();
2151   }
2152
2153   aResult &= mySceneTransformTexture->Init (theGlContext, 4,
2154     myRaytraceGeometry.Size() * 4, reinterpret_cast<const GLfloat*> (aNodeTransforms));
2155
2156   delete [] aNodeTransforms;
2157
2158   /////////////////////////////////////////////////////////////////////////////
2159   // Write geometry and bottom-level BVH buffers
2160
2161   Standard_Size aTotalVerticesNb = 0;
2162   Standard_Size aTotalElementsNb = 0;
2163   Standard_Size aTotalBVHNodesNb = 0;
2164
2165   for (Standard_Integer anElemIndex = 0; anElemIndex < myRaytraceGeometry.Size(); ++anElemIndex)
2166   {
2167     OpenGl_TriangleSet* aTriangleSet = dynamic_cast<OpenGl_TriangleSet*> (
2168       myRaytraceGeometry.Objects().ChangeValue (anElemIndex).operator->());
2169
2170     Standard_ASSERT_RETURN (aTriangleSet != NULL,
2171       "Error: Failed to get triangulation of OpenGL element", Standard_False);
2172
2173     aTotalVerticesNb += aTriangleSet->Vertices.size();
2174     aTotalElementsNb += aTriangleSet->Elements.size();
2175
2176     Standard_ASSERT_RETURN (!aTriangleSet->QuadBVH().IsNull(),
2177       "Error: Failed to get bottom-level BVH of OpenGL element", Standard_False);
2178
2179     aTotalBVHNodesNb += aTriangleSet->QuadBVH()->NodeInfoBuffer().size();
2180   }
2181
2182   aTotalBVHNodesNb += myRaytraceGeometry.QuadBVH()->NodeInfoBuffer().size();
2183
2184   if (aTotalBVHNodesNb != 0)
2185   {
2186     aResult &= mySceneNodeInfoTexture->Init (
2187       theGlContext, 4, GLsizei (aTotalBVHNodesNb), static_cast<const GLuint*>  (NULL));
2188     aResult &= mySceneMinPointTexture->Init (
2189       theGlContext, 3, GLsizei (aTotalBVHNodesNb), static_cast<const GLfloat*> (NULL));
2190     aResult &= mySceneMaxPointTexture->Init (
2191       theGlContext, 3, GLsizei (aTotalBVHNodesNb), static_cast<const GLfloat*> (NULL));
2192   }
2193
2194   if (!aResult)
2195   {
2196 #ifdef RAY_TRACE_PRINT_INFO
2197     std::cout << "Error: Failed to upload buffers for bottom-level scene BVH" << std::endl;
2198 #endif
2199     return Standard_False;
2200   }
2201
2202   if (aTotalElementsNb != 0)
2203   {
2204     aResult &= myGeometryTriangTexture->Init (
2205       theGlContext, 4, GLsizei (aTotalElementsNb), static_cast<const GLuint*> (NULL));
2206   }
2207
2208   if (aTotalVerticesNb != 0)
2209   {
2210     aResult &= myGeometryVertexTexture->Init (
2211       theGlContext, 3, GLsizei (aTotalVerticesNb), static_cast<const GLfloat*> (NULL));
2212     aResult &= myGeometryNormalTexture->Init (
2213       theGlContext, 3, GLsizei (aTotalVerticesNb), static_cast<const GLfloat*> (NULL));
2214     aResult &= myGeometryTexCrdTexture->Init (
2215       theGlContext, 2, GLsizei (aTotalVerticesNb), static_cast<const GLfloat*> (NULL));
2216   }
2217
2218   if (!aResult)
2219   {
2220 #ifdef RAY_TRACE_PRINT_INFO
2221     std::cout << "Error: Failed to upload buffers for scene geometry" << std::endl;
2222 #endif
2223     return Standard_False;
2224   }
2225
2226   const QuadBvhHandle& aBVH = myRaytraceGeometry.QuadBVH();
2227
2228   if (aBVH->Length() > 0)
2229   {
2230     aResult &= mySceneNodeInfoTexture->SubData (theGlContext, 0, aBVH->Length(),
2231       reinterpret_cast<const GLuint*> (&aBVH->NodeInfoBuffer().front()));
2232     aResult &= mySceneMinPointTexture->SubData (theGlContext, 0, aBVH->Length(),
2233       reinterpret_cast<const GLfloat*> (&aBVH->MinPointBuffer().front()));
2234     aResult &= mySceneMaxPointTexture->SubData (theGlContext, 0, aBVH->Length(),
2235       reinterpret_cast<const GLfloat*> (&aBVH->MaxPointBuffer().front()));
2236   }
2237
2238   for (Standard_Integer aNodeIdx = 0; aNodeIdx < aBVH->Length(); ++aNodeIdx)
2239   {
2240     if (!aBVH->IsOuter (aNodeIdx))
2241       continue;
2242
2243     OpenGl_TriangleSet* aTriangleSet = myRaytraceGeometry.TriangleSet (aNodeIdx);
2244
2245     Standard_ASSERT_RETURN (aTriangleSet != NULL,
2246       "Error: Failed to get triangulation of OpenGL element", Standard_False);
2247
2248     Standard_Integer aBVHOffset = myRaytraceGeometry.AccelerationOffset (aNodeIdx);
2249
2250     Standard_ASSERT_RETURN (aBVHOffset != OpenGl_RaytraceGeometry::INVALID_OFFSET,
2251       "Error: Failed to get offset for bottom-level BVH", Standard_False);
2252
2253     const Standard_Integer aBvhBuffersSize = aTriangleSet->QuadBVH()->Length();
2254
2255     if (aBvhBuffersSize != 0)
2256     {
2257       aResult &= mySceneNodeInfoTexture->SubData (theGlContext, aBVHOffset, aBvhBuffersSize,
2258         reinterpret_cast<const GLuint*> (&aTriangleSet->QuadBVH()->NodeInfoBuffer().front()));
2259       aResult &= mySceneMinPointTexture->SubData (theGlContext, aBVHOffset, aBvhBuffersSize,
2260         reinterpret_cast<const GLfloat*> (&aTriangleSet->QuadBVH()->MinPointBuffer().front()));
2261       aResult &= mySceneMaxPointTexture->SubData (theGlContext, aBVHOffset, aBvhBuffersSize,
2262         reinterpret_cast<const GLfloat*> (&aTriangleSet->QuadBVH()->MaxPointBuffer().front()));
2263
2264       if (!aResult)
2265       {
2266 #ifdef RAY_TRACE_PRINT_INFO
2267         std::cout << "Error: Failed to upload buffers for bottom-level scene BVHs" << std::endl;
2268 #endif
2269         return Standard_False;
2270       }
2271     }
2272
2273     const Standard_Integer aVerticesOffset = myRaytraceGeometry.VerticesOffset (aNodeIdx);
2274
2275     Standard_ASSERT_RETURN (aVerticesOffset != OpenGl_RaytraceGeometry::INVALID_OFFSET,
2276       "Error: Failed to get offset for triangulation vertices of OpenGL element", Standard_False);
2277
2278     if (!aTriangleSet->Vertices.empty())
2279     {
2280       aResult &= myGeometryNormalTexture->SubData (theGlContext, aVerticesOffset,
2281         GLsizei (aTriangleSet->Normals.size()), reinterpret_cast<const GLfloat*> (&aTriangleSet->Normals.front()));
2282       aResult &= myGeometryTexCrdTexture->SubData (theGlContext, aVerticesOffset,
2283         GLsizei (aTriangleSet->TexCrds.size()), reinterpret_cast<const GLfloat*> (&aTriangleSet->TexCrds.front()));
2284       aResult &= myGeometryVertexTexture->SubData (theGlContext, aVerticesOffset,
2285         GLsizei (aTriangleSet->Vertices.size()), reinterpret_cast<const GLfloat*> (&aTriangleSet->Vertices.front()));
2286     }
2287
2288     const Standard_Integer anElementsOffset = myRaytraceGeometry.ElementsOffset (aNodeIdx);
2289
2290     Standard_ASSERT_RETURN (anElementsOffset != OpenGl_RaytraceGeometry::INVALID_OFFSET,
2291       "Error: Failed to get offset for triangulation elements of OpenGL element", Standard_False);
2292
2293     if (!aTriangleSet->Elements.empty())
2294     {
2295       aResult &= myGeometryTriangTexture->SubData (theGlContext, anElementsOffset, GLsizei (aTriangleSet->Elements.size()),
2296                                                    reinterpret_cast<const GLuint*> (&aTriangleSet->Elements.front()));
2297     }
2298
2299     if (!aResult)
2300     {
2301 #ifdef RAY_TRACE_PRINT_INFO
2302       std::cout << "Error: Failed to upload triangulation buffers for OpenGL element" << std::endl;
2303 #endif
2304       return Standard_False;
2305     }
2306   }
2307
2308   /////////////////////////////////////////////////////////////////////////////
2309   // Write material buffer
2310
2311   if (myRaytraceGeometry.Materials.size() != 0)
2312   {
2313     aResult &= myRaytraceMaterialTexture->Init (theGlContext, 4,
2314       GLsizei (myRaytraceGeometry.Materials.size() * 19), myRaytraceGeometry.Materials.front().Packed());
2315
2316     if (!aResult)
2317     {
2318 #ifdef RAY_TRACE_PRINT_INFO
2319       std::cout << "Error: Failed to upload material buffer" << std::endl;
2320 #endif
2321       return Standard_False;
2322     }
2323   }
2324
2325   myIsRaytraceDataValid = myRaytraceGeometry.Objects().Size() != 0;
2326
2327 #ifdef RAY_TRACE_PRINT_INFO
2328
2329   Standard_ShortReal aMemTrgUsed = 0.f;
2330   Standard_ShortReal aMemBvhUsed = 0.f;
2331
2332   for (Standard_Integer anElemIdx = 0; anElemIdx < myRaytraceGeometry.Size(); ++anElemIdx)
2333   {
2334     OpenGl_TriangleSet* aTriangleSet = dynamic_cast<OpenGl_TriangleSet*> (myRaytraceGeometry.Objects()(anElemIdx).get());
2335
2336     aMemTrgUsed += static_cast<Standard_ShortReal> (
2337       aTriangleSet->Vertices.size() * sizeof (BVH_Vec3f));
2338     aMemTrgUsed += static_cast<Standard_ShortReal> (
2339       aTriangleSet->Normals.size() * sizeof (BVH_Vec3f));
2340     aMemTrgUsed += static_cast<Standard_ShortReal> (
2341       aTriangleSet->TexCrds.size() * sizeof (BVH_Vec2f));
2342     aMemTrgUsed += static_cast<Standard_ShortReal> (
2343       aTriangleSet->Elements.size() * sizeof (BVH_Vec4i));
2344
2345     aMemBvhUsed += static_cast<Standard_ShortReal> (
2346       aTriangleSet->QuadBVH()->NodeInfoBuffer().size() * sizeof (BVH_Vec4i));
2347     aMemBvhUsed += static_cast<Standard_ShortReal> (
2348       aTriangleSet->QuadBVH()->MinPointBuffer().size() * sizeof (BVH_Vec3f));
2349     aMemBvhUsed += static_cast<Standard_ShortReal> (
2350       aTriangleSet->QuadBVH()->MaxPointBuffer().size() * sizeof (BVH_Vec3f));
2351   }
2352
2353   aMemBvhUsed += static_cast<Standard_ShortReal> (
2354     myRaytraceGeometry.QuadBVH()->NodeInfoBuffer().size() * sizeof (BVH_Vec4i));
2355   aMemBvhUsed += static_cast<Standard_ShortReal> (
2356     myRaytraceGeometry.QuadBVH()->MinPointBuffer().size() * sizeof (BVH_Vec3f));
2357   aMemBvhUsed += static_cast<Standard_ShortReal> (
2358     myRaytraceGeometry.QuadBVH()->MaxPointBuffer().size() * sizeof (BVH_Vec3f));
2359
2360   std::cout << "GPU Memory Used (Mb):\n"
2361     << "\tFor mesh: " << aMemTrgUsed / 1048576 << "\n"
2362     << "\tFor BVHs: " << aMemBvhUsed / 1048576 << "\n";
2363
2364 #endif
2365
2366   return aResult;
2367 }
2368
2369 // =======================================================================
2370 // function : updateRaytraceLightSources
2371 // purpose  : Updates 3D scene light sources for ray-tracing
2372 // =======================================================================
2373 Standard_Boolean OpenGl_View::updateRaytraceLightSources (const OpenGl_Mat4& theInvModelView, const Handle(OpenGl_Context)& theGlContext)
2374 {
2375   std::vector<Handle(Graphic3d_CLight)> aLightSources;
2376   myRaytraceGeometry.Ambient = BVH_Vec4f (0.f, 0.f, 0.f, 0.f);
2377   if (myShadingModel != Graphic3d_TOSM_UNLIT
2378   && !myLights.IsNull())
2379   {
2380     const Graphic3d_Vec4& anAmbient = myLights->AmbientColor();
2381     myRaytraceGeometry.Ambient = BVH_Vec4f (anAmbient.r(), anAmbient.g(), anAmbient.b(), 0.0f);
2382
2383     // move positional light sources at the front of the list
2384     aLightSources.reserve (myLights->Extent());
2385     for (Graphic3d_LightSet::Iterator aLightIter (myLights, Graphic3d_LightSet::IterationFilter_ExcludeDisabledAndAmbient);
2386          aLightIter.More(); aLightIter.Next())
2387     {
2388       const Graphic3d_CLight& aLight = *aLightIter.Value();
2389       if (aLight.Type() != Graphic3d_TOLS_DIRECTIONAL)
2390       {
2391         aLightSources.push_back (aLightIter.Value());
2392       }
2393     }
2394
2395     for (Graphic3d_LightSet::Iterator aLightIter (myLights, Graphic3d_LightSet::IterationFilter_ExcludeDisabledAndAmbient);
2396          aLightIter.More(); aLightIter.Next())
2397     {
2398       if (aLightIter.Value()->Type() == Graphic3d_TOLS_DIRECTIONAL)
2399       {
2400         aLightSources.push_back (aLightIter.Value());
2401       }
2402     }
2403   }
2404
2405   // get number of 'real' (not ambient) light sources
2406   const size_t aNbLights = aLightSources.size();
2407   Standard_Boolean wasUpdated = myRaytraceGeometry.Sources.size () != aNbLights;
2408   if (wasUpdated)
2409   {
2410     myRaytraceGeometry.Sources.resize (aNbLights);
2411   }
2412
2413   for (size_t aLightIdx = 0, aRealIdx = 0; aLightIdx < aLightSources.size(); ++aLightIdx)
2414   {
2415     const Graphic3d_CLight& aLight = *aLightSources[aLightIdx];
2416     const Graphic3d_Vec4& aLightColor = aLight.PackedColor();
2417     BVH_Vec4f aEmission  (aLightColor.r() * aLight.Intensity(),
2418                           aLightColor.g() * aLight.Intensity(),
2419                           aLightColor.b() * aLight.Intensity(),
2420                           1.0f);
2421
2422     BVH_Vec4f aPosition (-aLight.PackedDirection().x(),
2423                          -aLight.PackedDirection().y(),
2424                          -aLight.PackedDirection().z(),
2425                          0.0f);
2426
2427     if (aLight.Type() != Graphic3d_TOLS_DIRECTIONAL)
2428     {
2429       aPosition = BVH_Vec4f (static_cast<float>(aLight.Position().X()),
2430                              static_cast<float>(aLight.Position().Y()),
2431                              static_cast<float>(aLight.Position().Z()),
2432                              1.0f);
2433
2434       // store smoothing radius in W-component
2435       aEmission.w() = Max (aLight.Smoothness(), 0.f);
2436     }
2437     else
2438     {
2439       // store cosine of smoothing angle in W-component
2440       aEmission.w() = cosf (Min (Max (aLight.Smoothness(), 0.f), static_cast<Standard_ShortReal> (M_PI / 2.0)));
2441     }
2442
2443     if (aLight.IsHeadlight())
2444     {
2445       aPosition = theInvModelView * aPosition;
2446     }
2447
2448     for (int aK = 0; aK < 4; ++aK)
2449     {
2450       wasUpdated |= (aEmission[aK] != myRaytraceGeometry.Sources[aRealIdx].Emission[aK])
2451                  || (aPosition[aK] != myRaytraceGeometry.Sources[aRealIdx].Position[aK]);
2452     }
2453
2454     if (wasUpdated)
2455     {
2456       myRaytraceGeometry.Sources[aRealIdx] = OpenGl_RaytraceLight (aEmission, aPosition);
2457     }
2458
2459     ++aRealIdx;
2460   }
2461
2462   if (myRaytraceLightSrcTexture.IsNull()) // create light source buffer
2463   {
2464     myRaytraceLightSrcTexture = new OpenGl_TextureBufferArb;
2465   }
2466
2467   if (myRaytraceGeometry.Sources.size() != 0 && wasUpdated)
2468   {
2469     const GLfloat* aDataPtr = myRaytraceGeometry.Sources.front().Packed();
2470     if (!myRaytraceLightSrcTexture->Init (theGlContext, 4, GLsizei (myRaytraceGeometry.Sources.size() * 2), aDataPtr))
2471     {
2472 #ifdef RAY_TRACE_PRINT_INFO
2473       std::cout << "Error: Failed to upload light source buffer" << std::endl;
2474 #endif
2475       return Standard_False;
2476     }
2477
2478     myAccumFrames = 0; // accumulation should be restarted
2479   }
2480
2481   return Standard_True;
2482 }
2483
2484 // =======================================================================
2485 // function : setUniformState
2486 // purpose  : Sets uniform state for the given ray-tracing shader program
2487 // =======================================================================
2488 Standard_Boolean OpenGl_View::setUniformState (const Standard_Integer        theProgramId,
2489                                                const Standard_Integer        theWinSizeX,
2490                                                const Standard_Integer        theWinSizeY,
2491                                                Graphic3d_Camera::Projection  theProjection,
2492                                                const Handle(OpenGl_Context)& theGlContext)
2493 {
2494   // Get projection state
2495   OpenGl_MatrixState<Standard_ShortReal>& aCntxProjectionState = theGlContext->ProjectionState;
2496
2497   OpenGl_Mat4 aViewPrjMat;
2498   OpenGl_Mat4 anUnviewMat;
2499   OpenGl_Vec3 aOrigins[4];
2500   OpenGl_Vec3 aDirects[4];
2501
2502   if (myCamera->IsOrthographic()
2503    || !myRenderParams.IsGlobalIlluminationEnabled)
2504   {
2505     updateCamera (myCamera->OrientationMatrixF(),
2506                   aCntxProjectionState.Current(),
2507                   aOrigins,
2508                   aDirects,
2509                   aViewPrjMat,
2510                   anUnviewMat);
2511   }
2512   else
2513   {
2514     updatePerspCameraPT (myCamera->OrientationMatrixF(),
2515                          aCntxProjectionState.Current(),
2516                          theProjection,
2517                          aViewPrjMat,
2518                          anUnviewMat,
2519                          theWinSizeX,
2520                          theWinSizeY);
2521   }
2522
2523   Handle(OpenGl_ShaderProgram)& theProgram = theProgramId == 0
2524                                            ? myRaytraceProgram
2525                                            : myPostFSAAProgram;
2526
2527   if (theProgram.IsNull())
2528   {
2529     return Standard_False;
2530   }
2531   
2532   theProgram->SetUniform(theGlContext, "uEyeOrig", myEyeOrig);
2533   theProgram->SetUniform(theGlContext, "uEyeView", myEyeView);
2534   theProgram->SetUniform(theGlContext, "uEyeVert", myEyeVert);
2535   theProgram->SetUniform(theGlContext, "uEyeSide", myEyeSide);
2536   theProgram->SetUniform(theGlContext, "uEyeSize", myEyeSize);
2537
2538   theProgram->SetUniform(theGlContext, "uApertureRadius", myRenderParams.CameraApertureRadius);
2539   theProgram->SetUniform(theGlContext, "uFocalPlaneDist", myRenderParams.CameraFocalPlaneDist);
2540   
2541   // Set camera state
2542   theProgram->SetUniform (theGlContext,
2543     myUniformLocations[theProgramId][OpenGl_RT_uOriginLB], aOrigins[0]);
2544   theProgram->SetUniform (theGlContext,
2545     myUniformLocations[theProgramId][OpenGl_RT_uOriginRB], aOrigins[1]);
2546   theProgram->SetUniform (theGlContext,
2547     myUniformLocations[theProgramId][OpenGl_RT_uOriginLT], aOrigins[2]);
2548   theProgram->SetUniform (theGlContext,
2549     myUniformLocations[theProgramId][OpenGl_RT_uOriginRT], aOrigins[3]);
2550   theProgram->SetUniform (theGlContext,
2551     myUniformLocations[theProgramId][OpenGl_RT_uDirectLB], aDirects[0]);
2552   theProgram->SetUniform (theGlContext,
2553     myUniformLocations[theProgramId][OpenGl_RT_uDirectRB], aDirects[1]);
2554   theProgram->SetUniform (theGlContext,
2555     myUniformLocations[theProgramId][OpenGl_RT_uDirectLT], aDirects[2]);
2556   theProgram->SetUniform (theGlContext,
2557     myUniformLocations[theProgramId][OpenGl_RT_uDirectRT], aDirects[3]);
2558   theProgram->SetUniform (theGlContext,
2559     myUniformLocations[theProgramId][OpenGl_RT_uViewPrMat], aViewPrjMat);
2560   theProgram->SetUniform (theGlContext,
2561     myUniformLocations[theProgramId][OpenGl_RT_uUnviewMat], anUnviewMat);
2562
2563   // Set screen dimensions
2564   myRaytraceProgram->SetUniform (theGlContext,
2565     myUniformLocations[theProgramId][OpenGl_RT_uWinSizeX], theWinSizeX);
2566   myRaytraceProgram->SetUniform (theGlContext,
2567     myUniformLocations[theProgramId][OpenGl_RT_uWinSizeY], theWinSizeY);
2568
2569   // Set 3D scene parameters
2570   theProgram->SetUniform (theGlContext,
2571     myUniformLocations[theProgramId][OpenGl_RT_uSceneRad], myRaytraceSceneRadius);
2572   theProgram->SetUniform (theGlContext,
2573     myUniformLocations[theProgramId][OpenGl_RT_uSceneEps], myRaytraceSceneEpsilon);
2574
2575   // Set light source parameters
2576   const Standard_Integer aLightSourceBufferSize =
2577     static_cast<Standard_Integer> (myRaytraceGeometry.Sources.size());
2578   
2579   theProgram->SetUniform (theGlContext,
2580     myUniformLocations[theProgramId][OpenGl_RT_uLightCount], aLightSourceBufferSize);
2581
2582   // Set array of 64-bit texture handles
2583   if (theGlContext->arbTexBindless != NULL && myRaytraceGeometry.HasTextures())
2584   {
2585     const std::vector<GLuint64>& aTextures = myRaytraceGeometry.TextureHandles();
2586
2587     theProgram->SetUniform (theGlContext, myUniformLocations[theProgramId][OpenGl_RT_uTexSamplersArray],
2588       static_cast<GLsizei> (aTextures.size()), reinterpret_cast<const OpenGl_Vec2u*> (&aTextures.front()));
2589   }
2590
2591   // Set background colors (only gradient background supported)
2592   if (myBgGradientArray != NULL && myBgGradientArray->IsDefined())
2593   {
2594     theProgram->SetUniform (theGlContext,
2595       myUniformLocations[theProgramId][OpenGl_RT_uBackColorTop], myBgGradientArray->GradientColor (0));
2596     theProgram->SetUniform (theGlContext,
2597       myUniformLocations[theProgramId][OpenGl_RT_uBackColorBot], myBgGradientArray->GradientColor (1));
2598   }
2599   else
2600   {
2601     const OpenGl_Vec4& aBackColor = myBgColor;
2602
2603     theProgram->SetUniform (theGlContext,
2604       myUniformLocations[theProgramId][OpenGl_RT_uBackColorTop], aBackColor);
2605     theProgram->SetUniform (theGlContext,
2606       myUniformLocations[theProgramId][OpenGl_RT_uBackColorBot], aBackColor);
2607   }
2608
2609   // Set environment map parameters
2610   const Standard_Boolean toDisableEnvironmentMap = myTextureEnv.IsNull()
2611                                                ||  myTextureEnv->IsEmpty()
2612                                                || !myTextureEnv->First()->IsValid();
2613
2614   theProgram->SetUniform (theGlContext,
2615     myUniformLocations[theProgramId][OpenGl_RT_uSphereMapEnabled], toDisableEnvironmentMap ? 0 : 1);
2616
2617   theProgram->SetUniform (theGlContext,
2618     myUniformLocations[theProgramId][OpenGl_RT_uSphereMapForBack], myRenderParams.UseEnvironmentMapBackground ?  1 : 0);
2619
2620   if (myRenderParams.IsGlobalIlluminationEnabled) // GI parameters
2621   {
2622     theProgram->SetUniform (theGlContext,
2623       myUniformLocations[theProgramId][OpenGl_RT_uMaxRadiance], myRenderParams.RadianceClampingValue);
2624
2625     theProgram->SetUniform (theGlContext,
2626       myUniformLocations[theProgramId][OpenGl_RT_uBlockedRngEnabled], myRenderParams.CoherentPathTracingMode ? 1 : 0);
2627
2628     // Check whether we should restart accumulation for run-time parameters
2629     if (myRenderParams.RadianceClampingValue       != myRaytraceParameters.RadianceClampingValue
2630      || myRenderParams.UseEnvironmentMapBackground != myRaytraceParameters.UseEnvMapForBackground)
2631     {
2632       myAccumFrames = 0; // accumulation should be restarted
2633
2634       myRaytraceParameters.RadianceClampingValue  = myRenderParams.RadianceClampingValue;
2635       myRaytraceParameters.UseEnvMapForBackground = myRenderParams.UseEnvironmentMapBackground;
2636     }
2637   }
2638   else // RT parameters
2639   {
2640     // Set ambient light source
2641     theProgram->SetUniform (theGlContext,
2642       myUniformLocations[theProgramId][OpenGl_RT_uLightAmbnt], myRaytraceGeometry.Ambient);
2643
2644     // Enable/disable run-time ray-tracing effects
2645     theProgram->SetUniform (theGlContext,
2646       myUniformLocations[theProgramId][OpenGl_RT_uShadowsEnabled], myRenderParams.IsShadowEnabled ?  1 : 0);
2647     theProgram->SetUniform (theGlContext,
2648       myUniformLocations[theProgramId][OpenGl_RT_uReflectEnabled], myRenderParams.IsReflectionEnabled ?  1 : 0);
2649   }
2650
2651   return Standard_True;
2652 }
2653
2654 // =======================================================================
2655 // function : bindRaytraceTextures
2656 // purpose  : Binds ray-trace textures to corresponding texture units
2657 // =======================================================================
2658 void OpenGl_View::bindRaytraceTextures (const Handle(OpenGl_Context)& theGlContext,
2659                                         int theStereoView)
2660 {
2661   if (myRaytraceParameters.AdaptiveScreenSampling
2662    && myRaytraceParameters.GlobalIllumination)
2663   {
2664   #if !defined(GL_ES_VERSION_2_0)
2665     theGlContext->core42->glBindImageTexture (OpenGl_RT_OutputImage,
2666                                               myRaytraceOutputTexture[theStereoView]->TextureId(), 0, GL_TRUE, 0, GL_READ_WRITE, GL_R32F);
2667     theGlContext->core42->glBindImageTexture (OpenGl_RT_VisualErrorImage,
2668                                               myRaytraceVisualErrorTexture[theStereoView]->TextureId(), 0, GL_TRUE, 0, GL_READ_WRITE, GL_R32I);
2669     if (myRaytraceParameters.AdaptiveScreenSamplingAtomic)
2670     {
2671       theGlContext->core42->glBindImageTexture (OpenGl_RT_TileOffsetsImage,
2672                                                 myRaytraceTileOffsetsTexture[theStereoView]->TextureId(), 0, GL_TRUE, 0, GL_READ_ONLY, GL_RG32I);
2673     }
2674     else
2675     {
2676       theGlContext->core42->glBindImageTexture (OpenGl_RT_TileSamplesImage,
2677                                                 myRaytraceTileSamplesTexture[theStereoView]->TextureId(), 0, GL_TRUE, 0, GL_READ_WRITE, GL_R32I);
2678     }
2679   #else
2680     (void )theStereoView;
2681   #endif
2682   }
2683
2684   if (!myTextureEnv.IsNull()
2685    && !myTextureEnv->IsEmpty()
2686    &&  myTextureEnv->First()->IsValid())
2687   {
2688     myTextureEnv->First()->Bind (theGlContext, OpenGl_RT_EnvironmentMapTexture);
2689   }
2690
2691   mySceneMinPointTexture   ->BindTexture (theGlContext, OpenGl_RT_SceneMinPointTexture);
2692   mySceneMaxPointTexture   ->BindTexture (theGlContext, OpenGl_RT_SceneMaxPointTexture);
2693   mySceneNodeInfoTexture   ->BindTexture (theGlContext, OpenGl_RT_SceneNodeInfoTexture);
2694   myGeometryVertexTexture  ->BindTexture (theGlContext, OpenGl_RT_GeometryVertexTexture);
2695   myGeometryNormalTexture  ->BindTexture (theGlContext, OpenGl_RT_GeometryNormalTexture);
2696   myGeometryTexCrdTexture  ->BindTexture (theGlContext, OpenGl_RT_GeometryTexCrdTexture);
2697   myGeometryTriangTexture  ->BindTexture (theGlContext, OpenGl_RT_GeometryTriangTexture);
2698   mySceneTransformTexture  ->BindTexture (theGlContext, OpenGl_RT_SceneTransformTexture);
2699   myRaytraceMaterialTexture->BindTexture (theGlContext, OpenGl_RT_RaytraceMaterialTexture);
2700   myRaytraceLightSrcTexture->BindTexture (theGlContext, OpenGl_RT_RaytraceLightSrcTexture);
2701 }
2702
2703 // =======================================================================
2704 // function : unbindRaytraceTextures
2705 // purpose  : Unbinds ray-trace textures from corresponding texture units
2706 // =======================================================================
2707 void OpenGl_View::unbindRaytraceTextures (const Handle(OpenGl_Context)& theGlContext)
2708 {
2709   mySceneMinPointTexture   ->UnbindTexture (theGlContext, OpenGl_RT_SceneMinPointTexture);
2710   mySceneMaxPointTexture   ->UnbindTexture (theGlContext, OpenGl_RT_SceneMaxPointTexture);
2711   mySceneNodeInfoTexture   ->UnbindTexture (theGlContext, OpenGl_RT_SceneNodeInfoTexture);
2712   myGeometryVertexTexture  ->UnbindTexture (theGlContext, OpenGl_RT_GeometryVertexTexture);
2713   myGeometryNormalTexture  ->UnbindTexture (theGlContext, OpenGl_RT_GeometryNormalTexture);
2714   myGeometryTexCrdTexture  ->UnbindTexture (theGlContext, OpenGl_RT_GeometryTexCrdTexture);
2715   myGeometryTriangTexture  ->UnbindTexture (theGlContext, OpenGl_RT_GeometryTriangTexture);
2716   mySceneTransformTexture  ->UnbindTexture (theGlContext, OpenGl_RT_SceneTransformTexture);
2717   myRaytraceMaterialTexture->UnbindTexture (theGlContext, OpenGl_RT_RaytraceMaterialTexture);
2718   myRaytraceLightSrcTexture->UnbindTexture (theGlContext, OpenGl_RT_RaytraceLightSrcTexture);
2719
2720   theGlContext->core15fwd->glActiveTexture (GL_TEXTURE0);
2721 }
2722
2723 // =======================================================================
2724 // function : runRaytraceShaders
2725 // purpose  : Runs ray-tracing shader programs
2726 // =======================================================================
2727 Standard_Boolean OpenGl_View::runRaytraceShaders (const Standard_Integer        theSizeX,
2728                                                   const Standard_Integer        theSizeY,
2729                                                   Graphic3d_Camera::Projection  theProjection,
2730                                                   OpenGl_FrameBuffer*           theReadDrawFbo,
2731                                                   const Handle(OpenGl_Context)& theGlContext)
2732 {
2733   Standard_Boolean aResult = theGlContext->BindProgram (myRaytraceProgram);
2734
2735   aResult &= setUniformState (0,
2736                               theSizeX,
2737                               theSizeY,
2738                               theProjection,
2739                               theGlContext);
2740
2741   if (myRaytraceParameters.GlobalIllumination) // path tracing
2742   {
2743     aResult &= runPathtrace    (theSizeX, theSizeY, theProjection, theGlContext);
2744     aResult &= runPathtraceOut (theProjection, theReadDrawFbo, theGlContext);
2745   }
2746   else // Whitted-style ray-tracing
2747   {
2748     aResult &= runRaytrace (theSizeX, theSizeY, theProjection, theReadDrawFbo, theGlContext);
2749   }
2750
2751   return aResult;
2752 }
2753
2754 // =======================================================================
2755 // function : runRaytrace
2756 // purpose  : Runs Whitted-style ray-tracing
2757 // =======================================================================
2758 Standard_Boolean OpenGl_View::runRaytrace (const Standard_Integer        theSizeX,
2759                                            const Standard_Integer        theSizeY,
2760                                            Graphic3d_Camera::Projection  theProjection,
2761                                            OpenGl_FrameBuffer*           theReadDrawFbo,
2762                                            const Handle(OpenGl_Context)& theGlContext)
2763 {
2764   Standard_Boolean aResult = Standard_True;
2765
2766   // Choose proper set of frame buffers for stereo rendering
2767   const Standard_Integer aFBOIdx = (theProjection == Graphic3d_Camera::Projection_MonoRightEye) ? 1 : 0;
2768   bindRaytraceTextures (theGlContext, aFBOIdx);
2769
2770   if (myRenderParams.IsAntialiasingEnabled) // if second FSAA pass is used
2771   {
2772     myRaytraceFBO1[aFBOIdx]->BindBuffer (theGlContext);
2773
2774     glClear (GL_DEPTH_BUFFER_BIT); // render the image with depth
2775   }
2776
2777   theGlContext->core20fwd->glDrawArrays (GL_TRIANGLES, 0, 6);
2778
2779   if (myRenderParams.IsAntialiasingEnabled)
2780   {
2781     glDisable (GL_DEPTH_TEST); // improve jagged edges without depth buffer
2782
2783     // bind ray-tracing output image as input
2784     myRaytraceFBO1[aFBOIdx]->ColorTexture()->Bind (theGlContext, OpenGl_RT_FsaaInputTexture);
2785
2786     aResult &= theGlContext->BindProgram (myPostFSAAProgram);
2787
2788     aResult &= setUniformState (1 /* FSAA ID */,
2789                                 theSizeX,
2790                                 theSizeY,
2791                                 theProjection,
2792                                 theGlContext);
2793
2794     // Perform multi-pass adaptive FSAA using ping-pong technique.
2795     // We use 'FLIPTRI' sampling pattern changing for every pixel
2796     // (3 additional samples per pixel, the 1st sample is already
2797     // available from initial ray-traced image).
2798     for (Standard_Integer anIt = 1; anIt < 4; ++anIt)
2799     {
2800       GLfloat aOffsetX = 1.f / theSizeX;
2801       GLfloat aOffsetY = 1.f / theSizeY;
2802
2803       if (anIt == 1)
2804       {
2805         aOffsetX *= -0.55f;
2806         aOffsetY *=  0.55f;
2807       }
2808       else if (anIt == 2)
2809       {
2810         aOffsetX *=  0.00f;
2811         aOffsetY *= -0.55f;
2812       }
2813       else if (anIt == 3)
2814       {
2815         aOffsetX *= 0.55f;
2816         aOffsetY *= 0.00f;
2817       }
2818
2819       aResult &= myPostFSAAProgram->SetUniform (theGlContext,
2820         myUniformLocations[1][OpenGl_RT_uSamples], anIt + 1);
2821       aResult &= myPostFSAAProgram->SetUniform (theGlContext,
2822         myUniformLocations[1][OpenGl_RT_uOffsetX], aOffsetX);
2823       aResult &= myPostFSAAProgram->SetUniform (theGlContext,
2824         myUniformLocations[1][OpenGl_RT_uOffsetY], aOffsetY);
2825
2826       Handle(OpenGl_FrameBuffer)& aFramebuffer = anIt % 2
2827                                                ? myRaytraceFBO2[aFBOIdx]
2828                                                : myRaytraceFBO1[aFBOIdx];
2829
2830       aFramebuffer->BindBuffer (theGlContext);
2831
2832       // perform adaptive FSAA pass
2833       theGlContext->core20fwd->glDrawArrays (GL_TRIANGLES, 0, 6);
2834
2835       aFramebuffer->ColorTexture()->Bind (theGlContext, OpenGl_RT_FsaaInputTexture);
2836     }
2837
2838     const Handle(OpenGl_FrameBuffer)& aRenderImageFramebuffer = myRaytraceFBO2[aFBOIdx];
2839     const Handle(OpenGl_FrameBuffer)& aDepthSourceFramebuffer = myRaytraceFBO1[aFBOIdx];
2840
2841     glEnable (GL_DEPTH_TEST);
2842
2843     // Display filtered image
2844     theGlContext->BindProgram (myOutImageProgram);
2845
2846     if (theReadDrawFbo != NULL)
2847     {
2848       theReadDrawFbo->BindBuffer (theGlContext);
2849     }
2850     else
2851     {
2852       aRenderImageFramebuffer->UnbindBuffer (theGlContext);
2853     }
2854
2855     aRenderImageFramebuffer->ColorTexture()       ->Bind (theGlContext, OpenGl_RT_PrevAccumTexture);
2856     aDepthSourceFramebuffer->DepthStencilTexture()->Bind (theGlContext, OpenGl_RT_RaytraceDepthTexture);
2857
2858     // copy the output image with depth values
2859     theGlContext->core20fwd->glDrawArrays (GL_TRIANGLES, 0, 6);
2860
2861     aDepthSourceFramebuffer->DepthStencilTexture()->Unbind (theGlContext, OpenGl_RT_RaytraceDepthTexture);
2862     aRenderImageFramebuffer->ColorTexture()       ->Unbind (theGlContext, OpenGl_RT_PrevAccumTexture);
2863   }
2864
2865   unbindRaytraceTextures (theGlContext);
2866
2867   theGlContext->BindProgram (NULL);
2868
2869   return aResult;
2870 }
2871
2872 // =======================================================================
2873 // function : runPathtrace
2874 // purpose  : Runs path tracing shader
2875 // =======================================================================
2876 Standard_Boolean OpenGl_View::runPathtrace (const Standard_Integer              theSizeX,
2877                                             const Standard_Integer              theSizeY,
2878                                             const Graphic3d_Camera::Projection  theProjection,
2879                                             const Handle(OpenGl_Context)&       theGlContext)
2880 {
2881   if (myToUpdateEnvironmentMap) // check whether the map was changed
2882   {
2883     myAccumFrames = myToUpdateEnvironmentMap = 0;
2884   }
2885   
2886   if (myRenderParams.CameraApertureRadius != myPrevCameraApertureRadius
2887    || myRenderParams.CameraFocalPlaneDist != myPrevCameraFocalPlaneDist)
2888   {
2889     myPrevCameraApertureRadius = myRenderParams.CameraApertureRadius;
2890     myPrevCameraFocalPlaneDist = myRenderParams.CameraFocalPlaneDist;
2891     myAccumFrames = 0;
2892   }
2893
2894   // Choose proper set of frame buffers for stereo rendering
2895   const Standard_Integer aFBOIdx = (theProjection == Graphic3d_Camera::Projection_MonoRightEye) ? 1 : 0;
2896
2897   if (myRaytraceParameters.AdaptiveScreenSampling)
2898   {
2899     if (myAccumFrames == 0)
2900     {
2901       myTileSampler.Reset(); // reset tile sampler to its initial state
2902
2903       // Adaptive sampling is starting at the second frame
2904       if (myRaytraceParameters.AdaptiveScreenSamplingAtomic)
2905       {
2906         myTileSampler.UploadOffsets (theGlContext, myRaytraceTileOffsetsTexture[aFBOIdx], false);
2907       }
2908       else
2909       {
2910         myTileSampler.UploadSamples (theGlContext, myRaytraceTileSamplesTexture[aFBOIdx], false);
2911       }
2912
2913     #if !defined(GL_ES_VERSION_2_0)
2914       theGlContext->core44->glClearTexImage (myRaytraceOutputTexture[aFBOIdx]->TextureId(), 0, GL_RED, GL_FLOAT, NULL);
2915     #endif
2916     }
2917
2918     // Clear adaptive screen sampling images
2919   #if !defined(GL_ES_VERSION_2_0)
2920     theGlContext->core44->glClearTexImage (myRaytraceVisualErrorTexture[aFBOIdx]->TextureId(), 0, GL_RED_INTEGER, GL_INT, NULL);
2921   #endif
2922   }
2923
2924   bindRaytraceTextures (theGlContext, aFBOIdx);
2925
2926   const Handle(OpenGl_FrameBuffer)& anAccumImageFramebuffer = myAccumFrames % 2 ? myRaytraceFBO2[aFBOIdx] : myRaytraceFBO1[aFBOIdx];
2927   anAccumImageFramebuffer->ColorTexture()->Bind (theGlContext, OpenGl_RT_PrevAccumTexture);
2928
2929   // Set frame accumulation weight
2930   myRaytraceProgram->SetUniform (theGlContext, myUniformLocations[0][OpenGl_RT_uAccumSamples], myAccumFrames);
2931
2932   // Set image uniforms for render program
2933   if (myRaytraceParameters.AdaptiveScreenSampling)
2934   {
2935     myRaytraceProgram->SetUniform (theGlContext, myUniformLocations[0][OpenGl_RT_uRenderImage], OpenGl_RT_OutputImage);
2936     myRaytraceProgram->SetUniform (theGlContext, myUniformLocations[0][OpenGl_RT_uTilesImage],  OpenGl_RT_TileSamplesImage);
2937     myRaytraceProgram->SetUniform (theGlContext, myUniformLocations[0][OpenGl_RT_uOffsetImage], OpenGl_RT_TileOffsetsImage);
2938     myRaytraceProgram->SetUniform (theGlContext, myUniformLocations[0][OpenGl_RT_uTileSize], myTileSampler.TileSize());
2939   }
2940
2941   const Handle(OpenGl_FrameBuffer)& aRenderImageFramebuffer = myAccumFrames % 2 ? myRaytraceFBO1[aFBOIdx] : myRaytraceFBO2[aFBOIdx];
2942   aRenderImageFramebuffer->BindBuffer (theGlContext);
2943   if (myRaytraceParameters.AdaptiveScreenSampling
2944    && myRaytraceParameters.AdaptiveScreenSamplingAtomic)
2945   {
2946     // extend viewport here, so that tiles at boundaries (cut tile size by target rendering viewport)
2947     // redirected to inner tiles (full tile size) are drawn entirely
2948     const Graphic3d_Vec2i anOffsetViewport = myTileSampler.OffsetTilesViewport (myAccumFrames > 1); // shrunk offsets texture will be uploaded since 3rd frame
2949     glViewport (0, 0, anOffsetViewport.x(), anOffsetViewport.y());
2950   }
2951
2952   // Generate for the given RNG seed
2953   glDisable (GL_DEPTH_TEST);
2954
2955   // Adaptive Screen Sampling computes the same overall amount of samples per frame redraw as normal Path Tracing,
2956   // but distributes them unequally across pixels (grouped in tiles), so that some pixels do not receive new samples at all.
2957   //
2958   // Offsets map (redirecting currently rendered tile to another tile) allows performing Adaptive Screen Sampling in single pass,
2959   // but current implementation relies on atomic float operations (AdaptiveScreenSamplingAtomic) for this.
2960   // So that when atomic floats are not supported by GPU, multi-pass rendering is used instead.
2961   //
2962   // Single-pass rendering is more optimal due to smaller amount of draw calls,
2963   // memory synchronization barriers, discarding most of the fragments and bad parallelization in case of very small amount of tiles requiring more samples.
2964   // However, atomic operations on float values still produces different result (close, but not bit exact) making non-regression testing not robust.
2965   // It should be possible following single-pass rendering approach but using extra accumulation buffer and resolving pass as possible improvement.
2966   const int aNbPasses = myRaytraceParameters.AdaptiveScreenSampling
2967                     && !myRaytraceParameters.AdaptiveScreenSamplingAtomic
2968                       ? myTileSampler.MaxTileSamples()
2969                       : 1;
2970   if (myAccumFrames == 0)
2971   {
2972     myRNG.SetSeed(); // start RNG from beginning
2973   }
2974   for (int aPassIter = 0; aPassIter < aNbPasses; ++aPassIter)
2975   {
2976     myRaytraceProgram->SetUniform (theGlContext, myUniformLocations[0][OpenGl_RT_uFrameRndSeed], static_cast<Standard_Integer> (myRNG.NextInt() >> 2));
2977     theGlContext->core20fwd->glDrawArrays (GL_TRIANGLES, 0, 6);
2978     if (myRaytraceParameters.AdaptiveScreenSampling)
2979     {
2980     #if !defined(GL_ES_VERSION_2_0)
2981       theGlContext->core44->glMemoryBarrier (GL_SHADER_IMAGE_ACCESS_BARRIER_BIT);
2982     #endif
2983     }
2984   }
2985   aRenderImageFramebuffer->UnbindBuffer (theGlContext);
2986
2987   if (myRaytraceParameters.AdaptiveScreenSampling
2988    && myRaytraceParameters.AdaptiveScreenSamplingAtomic)
2989   {
2990     glViewport (0, 0, theSizeX, theSizeY);
2991   }
2992   return true;
2993 }
2994
2995 // =======================================================================
2996 // function : runPathtraceOut
2997 // purpose  :
2998 // =======================================================================
2999 Standard_Boolean OpenGl_View::runPathtraceOut (const Graphic3d_Camera::Projection  theProjection,
3000                                                OpenGl_FrameBuffer*                 theReadDrawFbo,
3001                                                const Handle(OpenGl_Context)&       theGlContext)
3002 {
3003   // Output accumulated path traced image
3004   theGlContext->BindProgram (myOutImageProgram);
3005
3006   // Choose proper set of frame buffers for stereo rendering
3007   const Standard_Integer aFBOIdx = (theProjection == Graphic3d_Camera::Projection_MonoRightEye) ? 1 : 0;
3008
3009   if (myRaytraceParameters.AdaptiveScreenSampling)
3010   {
3011     // Set uniforms for display program
3012     myOutImageProgram->SetUniform (theGlContext, "uRenderImage",   OpenGl_RT_OutputImage);
3013     myOutImageProgram->SetUniform (theGlContext, "uAccumFrames",   myAccumFrames);
3014     myOutImageProgram->SetUniform (theGlContext, "uVarianceImage", OpenGl_RT_VisualErrorImage);
3015     myOutImageProgram->SetUniform (theGlContext, "uDebugAdaptive", myRenderParams.ShowSamplingTiles ?  1 : 0);
3016     myOutImageProgram->SetUniform (theGlContext, "uTileSize",      myTileSampler.TileSize());
3017     myOutImageProgram->SetUniform (theGlContext, "uVarianceScaleFactor", myTileSampler.VarianceScaleFactor());
3018   }
3019
3020   if (myRaytraceParameters.GlobalIllumination)
3021   {
3022     myOutImageProgram->SetUniform(theGlContext, "uExposure", myRenderParams.Exposure);
3023     switch (myRaytraceParameters.ToneMappingMethod)
3024     {
3025       case Graphic3d_ToneMappingMethod_Disabled:
3026         break;
3027       case Graphic3d_ToneMappingMethod_Filmic:
3028         myOutImageProgram->SetUniform (theGlContext, "uWhitePoint", myRenderParams.WhitePoint);
3029         break;
3030     }
3031   }
3032
3033   if (theReadDrawFbo != NULL)
3034   {
3035     theReadDrawFbo->BindBuffer (theGlContext);
3036   }
3037
3038   const Handle(OpenGl_FrameBuffer)& aRenderImageFramebuffer = myAccumFrames % 2 ? myRaytraceFBO1[aFBOIdx] : myRaytraceFBO2[aFBOIdx];
3039   aRenderImageFramebuffer->ColorTexture()->Bind (theGlContext, OpenGl_RT_PrevAccumTexture);
3040
3041   // Copy accumulated image with correct depth values
3042   glEnable (GL_DEPTH_TEST);
3043   theGlContext->core20fwd->glDrawArrays (GL_TRIANGLES, 0, 6);
3044
3045   aRenderImageFramebuffer->ColorTexture()->Unbind (theGlContext, OpenGl_RT_PrevAccumTexture);
3046
3047   if (myRaytraceParameters.AdaptiveScreenSampling)
3048   {
3049     // Download visual error map from the GPU and build adjusted tile offsets for optimal image sampling
3050     myTileSampler.GrabVarianceMap (theGlContext, myRaytraceVisualErrorTexture[aFBOIdx]);
3051     if (myRaytraceParameters.AdaptiveScreenSamplingAtomic)
3052     {
3053       myTileSampler.UploadOffsets (theGlContext, myRaytraceTileOffsetsTexture[aFBOIdx], myAccumFrames != 0);
3054     }
3055     else
3056     {
3057       myTileSampler.UploadSamples (theGlContext, myRaytraceTileSamplesTexture[aFBOIdx], myAccumFrames != 0);
3058     }
3059   }
3060
3061   unbindRaytraceTextures (theGlContext);
3062   theGlContext->BindProgram (NULL);
3063   return true;
3064 }
3065
3066 // =======================================================================
3067 // function : raytrace
3068 // purpose  : Redraws the window using OpenGL/GLSL ray-tracing
3069 // =======================================================================
3070 Standard_Boolean OpenGl_View::raytrace (const Standard_Integer        theSizeX,
3071                                         const Standard_Integer        theSizeY,
3072                                         Graphic3d_Camera::Projection  theProjection,
3073                                         OpenGl_FrameBuffer*           theReadDrawFbo,
3074                                         const Handle(OpenGl_Context)& theGlContext)
3075 {
3076   if (!initRaytraceResources (theSizeX, theSizeY, theGlContext))
3077   {
3078     return Standard_False;
3079   }
3080
3081   if (!updateRaytraceBuffers (theSizeX, theSizeY, theGlContext))
3082   {
3083     return Standard_False;
3084   }
3085
3086   OpenGl_Mat4 aLightSourceMatrix;
3087
3088   // Get inversed model-view matrix for transforming lights
3089   myCamera->OrientationMatrixF().Inverted (aLightSourceMatrix);
3090
3091   if (!updateRaytraceLightSources (aLightSourceMatrix, theGlContext))
3092   {
3093     return Standard_False;
3094   }
3095
3096   // Generate image using Whitted-style ray-tracing or path tracing
3097   if (myIsRaytraceDataValid)
3098   {
3099     myRaytraceScreenQuad.BindVertexAttrib (theGlContext, Graphic3d_TOA_POS);
3100
3101     if (!myRaytraceGeometry.AcquireTextures (theGlContext))
3102     {
3103       theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_ERROR,
3104         0, GL_DEBUG_SEVERITY_MEDIUM, "Error: Failed to acquire OpenGL image textures");
3105     }
3106
3107     glDisable (GL_BLEND);
3108
3109     const Standard_Boolean aResult = runRaytraceShaders (theSizeX,
3110                                                          theSizeY,
3111                                                          theProjection,
3112                                                          theReadDrawFbo,
3113                                                          theGlContext);
3114
3115     if (!aResult)
3116     {
3117       theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_ERROR,
3118         0, GL_DEBUG_SEVERITY_MEDIUM, "Error: Failed to execute ray-tracing shaders");
3119     }
3120
3121     if (!myRaytraceGeometry.ReleaseTextures (theGlContext))
3122     {
3123       theGlContext->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_ERROR,
3124         0, GL_DEBUG_SEVERITY_MEDIUM, "Error: Failed to release OpenGL image textures");
3125     }
3126
3127     myRaytraceScreenQuad.UnbindVertexAttrib (theGlContext, Graphic3d_TOA_POS);
3128   }
3129
3130   return Standard_True;
3131 }