1 // Created on: 1993-10-27
2 // Created by: Jean-LOuis FRENKEL
3 // Copyright (c) 1993-1999 Matra Datavision
4 // Copyright (c) 1999-2014 OPEN CASCADE SAS
5 //
6 // This file is part of Open CASCADE Technology software library.
7 //
8 // This library is free software; you can redistribute it and/or modify it under
9 // the terms of the GNU Lesser General Public License version 2.1 as published
10 // by the Free Software Foundation, with special exception defined in the file
11 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
12 // distribution for complete text of the license and disclaimer of any warranty.
13 //
14 // Alternatively, this file may be used under the terms of Open CASCADE
15 // commercial license or contractual agreement.
16 
17 #include <StdPrs_ToolTriangulatedShape.hxx>
18 
19 #include <BRepBndLib.hxx>
20 #include <BRepMesh_DiscretFactory.hxx>
21 #include <BRepMesh_DiscretRoot.hxx>
22 #include <BRepTools.hxx>
23 #include <BRep_Tool.hxx>
24 #include <GeomAbs_SurfaceType.hxx>
25 #include <GeomLib.hxx>
26 #include <gp_XYZ.hxx>
27 #include <Poly.hxx>
28 #include <Poly_Connect.hxx>
29 #include <Poly_Triangulation.hxx>
30 #include <Precision.hxx>
31 #include <Prs3d.hxx>
32 #include <Prs3d_Drawer.hxx>
33 #include <TColgp_Array1OfPnt.hxx>
34 #include <TColgp_Array1OfPnt2d.hxx>
35 #include <TopAbs_Orientation.hxx>
36 #include <TopLoc_Location.hxx>
37 #include <TShort_HArray1OfShortReal.hxx>
38 #include <TShort_Array1OfShortReal.hxx>
39 #include <TopExp_Explorer.hxx>
40 #include <TopoDS.hxx>
41 #include <TopoDS_Face.hxx>
42 
43 //=======================================================================
44 //function : IsTriangulated
45 //purpose  :
46 //=======================================================================
IsTriangulated(const TopoDS_Shape & theShape)47 Standard_Boolean StdPrs_ToolTriangulatedShape::IsTriangulated (const TopoDS_Shape& theShape)
48 {
49   TopLoc_Location aLocDummy;
50   for (TopExp_Explorer aFaceIter (theShape, TopAbs_FACE); aFaceIter.More(); aFaceIter.Next())
51   {
52     const TopoDS_Face&                aFace = TopoDS::Face (aFaceIter.Current());
53     const Handle(Poly_Triangulation)& aTri  = BRep_Tool::Triangulation (aFace, aLocDummy);
54     if (aTri.IsNull())
55     {
56       return Standard_False;
57     }
58   }
59   return Standard_True;
60 }
61 
62 //=======================================================================
63 //function : IsClosed
64 //purpose  :
65 //=======================================================================
IsClosed(const TopoDS_Shape & theShape)66 Standard_Boolean StdPrs_ToolTriangulatedShape::IsClosed (const TopoDS_Shape& theShape)
67 {
68   if (theShape.IsNull())
69   {
70     return Standard_True;
71   }
72 
73   switch (theShape.ShapeType())
74   {
75     case TopAbs_COMPOUND:
76     case TopAbs_COMPSOLID:
77     default:
78     {
79       // check that compound consists of closed solids
80       for (TopoDS_Iterator anIter (theShape); anIter.More(); anIter.Next())
81       {
82         const TopoDS_Shape& aShape = anIter.Value();
83         if (!IsClosed (aShape))
84         {
85           return Standard_False;
86         }
87       }
88       return Standard_True;
89     }
90     case TopAbs_SOLID:
91     {
92       // Check for non-manifold topology first of all:
93       // have to use BRep_Tool::IsClosed() because it checks the face connectivity
94       // inside the shape
95       if (!BRep_Tool::IsClosed (theShape))
96         return Standard_False;
97 
98       for (TopoDS_Iterator anIter (theShape); anIter.More(); anIter.Next())
99       {
100         const TopoDS_Shape& aShape = anIter.Value();
101         if (aShape.IsNull())
102         {
103           continue;
104         }
105 
106         if (aShape.ShapeType() == TopAbs_FACE)
107         {
108           // invalid solid
109           return Standard_False;
110         }
111         else if (!IsTriangulated (aShape))
112         {
113           // mesh contains holes
114           return Standard_False;
115         }
116       }
117       return Standard_True;
118     }
119     case TopAbs_SHELL:
120     case TopAbs_FACE:
121     {
122       // free faces / shell are not allowed
123       return Standard_False;
124     }
125     case TopAbs_WIRE:
126     case TopAbs_EDGE:
127     case TopAbs_VERTEX:
128     {
129       // ignore
130       return Standard_True;
131     }
132   }
133 }
134 
135 //=======================================================================
136 //function : ComputeNormals
137 //purpose  :
138 //=======================================================================
ComputeNormals(const TopoDS_Face & theFace,const Handle (Poly_Triangulation)& theTris,Poly_Connect & thePolyConnect)139 void StdPrs_ToolTriangulatedShape::ComputeNormals (const TopoDS_Face& theFace,
140                                                    const Handle(Poly_Triangulation)& theTris,
141                                                    Poly_Connect& thePolyConnect)
142 {
143   if (theTris.IsNull()
144    || theTris->HasNormals())
145   {
146     return;
147   }
148 
149   // take in face the surface location
150   const TopoDS_Face    aZeroFace = TopoDS::Face (theFace.Located (TopLoc_Location()));
151   Handle(Geom_Surface) aSurf     = BRep_Tool::Surface (aZeroFace);
152   if (!theTris->HasUVNodes() || aSurf.IsNull())
153   {
154     // compute normals by averaging triangulation normals sharing the same vertex
155     Poly::ComputeNormals (theTris);
156     return;
157   }
158 
159   const Standard_Real aTol = Precision::Confusion();
160   Standard_Integer aTri[3];
161   gp_Dir aNorm;
162   theTris->AddNormals();
163   for (Standard_Integer aNodeIter = 1; aNodeIter <= theTris->NbNodes(); ++aNodeIter)
164   {
165     // try to retrieve normal from real surface first, when UV coordinates are available
166     if (GeomLib::NormEstim (aSurf, theTris->UVNode (aNodeIter), aTol, aNorm) > 1)
167     {
168       if (thePolyConnect.Triangulation() != theTris)
169       {
170         thePolyConnect.Load (theTris);
171       }
172 
173       // compute flat normals
174       gp_XYZ eqPlan (0.0, 0.0, 0.0);
175       for (thePolyConnect.Initialize (aNodeIter); thePolyConnect.More(); thePolyConnect.Next())
176       {
177         theTris->Triangle (thePolyConnect.Value()).Get (aTri[0], aTri[1], aTri[2]);
178         const gp_XYZ v1 (theTris->Node (aTri[1]).Coord() - theTris->Node (aTri[0]).Coord());
179         const gp_XYZ v2 (theTris->Node (aTri[2]).Coord() - theTris->Node (aTri[1]).Coord());
180         const gp_XYZ vv = v1 ^ v2;
181         const Standard_Real aMod = vv.Modulus();
182         if (aMod >= aTol)
183         {
184           eqPlan += vv / aMod;
185         }
186       }
187       const Standard_Real aModMax = eqPlan.Modulus();
188       aNorm = (aModMax > aTol) ? gp_Dir (eqPlan) : gp::DZ();
189     }
190 
191     theTris->SetNormal (aNodeIter, aNorm);
192   }
193 }
194 
195 //=======================================================================
196 //function : Normal
197 //purpose  :
198 //=======================================================================
Normal(const TopoDS_Face & theFace,Poly_Connect & thePolyConnect,TColgp_Array1OfDir & theNormals)199 void StdPrs_ToolTriangulatedShape::Normal (const TopoDS_Face&  theFace,
200                                            Poly_Connect&       thePolyConnect,
201                                            TColgp_Array1OfDir& theNormals)
202 {
203   const Handle(Poly_Triangulation)& aPolyTri = thePolyConnect.Triangulation();
204   if (!aPolyTri->HasNormals())
205   {
206     ComputeNormals (theFace, aPolyTri, thePolyConnect);
207   }
208 
209   gp_Vec3f aNormal;
210   for (Standard_Integer aNodeIter = 1; aNodeIter <= aPolyTri->NbNodes(); ++aNodeIter)
211   {
212     aPolyTri->Normal (aNodeIter, aNormal);
213     theNormals.ChangeValue (aNodeIter).SetCoord (aNormal.x(), aNormal.y(), aNormal.z());
214   }
215 
216   if (theFace.Orientation() == TopAbs_REVERSED)
217   {
218     for (Standard_Integer aNodeIter = 1; aNodeIter <= aPolyTri->NbNodes(); ++aNodeIter)
219     {
220       theNormals.ChangeValue (aNodeIter).Reverse();
221     }
222   }
223 }
224 
225 //=======================================================================
226 //function : GetDeflection
227 //purpose  :
228 //=======================================================================
GetDeflection(const TopoDS_Shape & theShape,const Handle (Prs3d_Drawer)& theDrawer)229 Standard_Real StdPrs_ToolTriangulatedShape::GetDeflection (const TopoDS_Shape& theShape,
230                                                            const Handle(Prs3d_Drawer)& theDrawer)
231 {
232   if (theDrawer->TypeOfDeflection() != Aspect_TOD_RELATIVE)
233   {
234     return theDrawer->MaximalChordialDeviation();
235   }
236 
237   Bnd_Box aBndBox;
238   BRepBndLib::Add (theShape, aBndBox, Standard_False);
239   if (aBndBox.IsVoid())
240   {
241     return theDrawer->MaximalChordialDeviation();
242   }
243   else if (aBndBox.IsOpen())
244   {
245     if (!aBndBox.HasFinitePart())
246     {
247       return theDrawer->MaximalChordialDeviation();
248     }
249     aBndBox = aBndBox.FinitePart();
250   }
251 
252   // store computed relative deflection of shape as absolute deviation coefficient in case relative type to use it later on for sub-shapes
253   const Standard_Real aDeflection = Prs3d::GetDeflection (aBndBox, theDrawer->DeviationCoefficient(), theDrawer->MaximalChordialDeviation());
254   theDrawer->SetMaximalChordialDeviation (aDeflection);
255   return aDeflection;
256 }
257 
258 //=======================================================================
259 //function : IsTessellated
260 //purpose  :
261 //=======================================================================
IsTessellated(const TopoDS_Shape & theShape,const Handle (Prs3d_Drawer)& theDrawer)262 Standard_Boolean StdPrs_ToolTriangulatedShape::IsTessellated (const TopoDS_Shape&         theShape,
263                                                               const Handle(Prs3d_Drawer)& theDrawer)
264 {
265   return BRepTools::Triangulation (theShape, GetDeflection (theShape, theDrawer), true);
266 }
267 
268 // =======================================================================
269 // function : Tessellate
270 // purpose  :
271 // =======================================================================
Tessellate(const TopoDS_Shape & theShape,const Handle (Prs3d_Drawer)& theDrawer)272 Standard_Boolean StdPrs_ToolTriangulatedShape::Tessellate (const TopoDS_Shape&         theShape,
273                                                            const Handle(Prs3d_Drawer)& theDrawer)
274 {
275   Standard_Boolean wasRecomputed = Standard_False;
276   // Check if it is possible to avoid unnecessary recomputation of shape triangulation
277   if (IsTessellated (theShape, theDrawer))
278   {
279     return wasRecomputed;
280   }
281 
282   const Standard_Real aDeflection = GetDeflection (theShape, theDrawer);
283 
284   // retrieve meshing tool from Factory
285   Handle(BRepMesh_DiscretRoot) aMeshAlgo = BRepMesh_DiscretFactory::Get().Discret (theShape,
286                                                                                    aDeflection,
287                                                                                    theDrawer->DeviationAngle());
288   if (!aMeshAlgo.IsNull())
289   {
290     aMeshAlgo->Perform();
291     wasRecomputed = Standard_True;
292   }
293 
294   return wasRecomputed;
295 }
296 
297 // =======================================================================
298 // function : ClearOnOwnDeflectionChange
299 // purpose  :
300 // =======================================================================
ClearOnOwnDeflectionChange(const TopoDS_Shape & theShape,const Handle (Prs3d_Drawer)& theDrawer,const Standard_Boolean theToResetCoeff)301 void StdPrs_ToolTriangulatedShape::ClearOnOwnDeflectionChange (const TopoDS_Shape&         theShape,
302                                                                const Handle(Prs3d_Drawer)& theDrawer,
303                                                                const Standard_Boolean      theToResetCoeff)
304 {
305   if (!theDrawer->IsAutoTriangulation()
306     || theShape.IsNull())
307   {
308     return;
309   }
310 
311   const Standard_Boolean isOwnDeviationAngle       = theDrawer->HasOwnDeviationAngle();
312   const Standard_Boolean isOwnDeviationCoefficient = theDrawer->HasOwnDeviationCoefficient();
313   const Standard_Real anAngleNew  = theDrawer->DeviationAngle();
314   const Standard_Real anAnglePrev = theDrawer->PreviousDeviationAngle();
315   const Standard_Real aCoeffNew   = theDrawer->DeviationCoefficient();
316   const Standard_Real aCoeffPrev  = theDrawer->PreviousDeviationCoefficient();
317   if ((!isOwnDeviationAngle       || Abs (anAngleNew - anAnglePrev) <= Precision::Angular())
318    && (!isOwnDeviationCoefficient || Abs (aCoeffNew  - aCoeffPrev)  <= Precision::Confusion()))
319   {
320     return;
321   }
322 
323   BRepTools::Clean (theShape);
324   if (theToResetCoeff)
325   {
326     theDrawer->UpdatePreviousDeviationAngle();
327     theDrawer->UpdatePreviousDeviationCoefficient();
328   }
329 }
330