0028426: Implementation of the EdgesToFaces function

1. The two new methods have been implemented:
a. BOPAlgo_Tools::EdgesToWires - allows creating planar wires from edges.
The input edges may be not shared, but the output wires will be sharing the coinciding vertices and edges.
It is possible to skip the sharing if the input edges are already shared by passing the corresponding flag into the method.
The input edges are expected to be planar, but the method does not check it. Thus, if the input edges are not planar, the output wires will also be not planar.
In general, the output wires will be non-manifold and may contain free vertices.

b. BOPAlgo_Tools::WiresToFaces - allows creating planar faces from the planar wires.
In general, the input wires are non-manifold and may be not closed, but should share the coinciding parts.
The wires located in the same plane and completely included into other wires will create holes in the faces built from bigger wires

These two methods combined allow building faces from set of edges randomly located in 3D space.

2. The DRAW command *edgestofaces* has been implemented.

3. The documentation has been updated with the new section in Modeling Algorithms - Topological Tools.

4. Test cases for the issue.

src/BOPAlgo/BOPAlgo_Tools.hxx

@@ -31,6 +31,7 @@
 class BOPDS_PaveBlock;
 class BOPDS_CommonBlock;
 class IntTools_Context;
+class TopoDS_Shape;
 
 class BOPAlgo_Tools 
 {
@@ -58,6 +59,47 @@ public:
                                          const BOPDS_PDS theDS,
                                          const Handle(IntTools_Context)& theContext);
 
+  //! Creates planar wires from the given edges.<br>
+  //! The input edges are expected to be planar. And for the performance
+  //! sake the method does not check if the edges are really planar.<br>
+  //! Thus, the result wires will also be not planar if the input edges are not planar.<br>
+  //! The edges may be not shared, but the resulting wires will be sharing the
+  //! coinciding parts and intersecting parts.<br>
+  //! The output wires may be non-manifold and contain free and multi-connected vertices.<br>
+  //! Parameters:
+  //! <theEdges> - input edges;<br>
+  //! <theWires> - output wires;<br>
+  //! <theShared> - boolean flag which defines whether the input edges are already
+  //!               shared or have to be intersected;<br>
+  //! <theAngTol> - the angular tolerance which will be used for distinguishing
+  //!               the planes in which the edges are located. Default value is
+  //!               1.e-8 which is used for intersection of planes in IntTools_FaceFace.<br>
+  //! Method returns the following error statuses:<br>
+  //! 0 - in case of success (at least one wire has been built);<br>
+  //! 1 - in case there are no edges in the given shape;<br>
+  //! 2 - sharing of the edges has failed.<br>
+  Standard_EXPORT static Standard_Integer EdgesToWires(const TopoDS_Shape& theEdges,
+                                                       TopoDS_Shape& theWires,
+                                                       const Standard_Boolean theShared = Standard_False,
+                                                       const Standard_Real theAngTol = 1.e-8);
+
+  //! Creates planar faces from given planar wires.<br>
+  //! The method does not check if the wires are really planar.<br>
+  //! The input wires may be non-manifold but should be shared.<br>
+  //! The wires located in the same planes and included into other wires will create
+  //! holes in the faces built from outer wires.<br>
+  //! The tolerance values of the input shapes may be modified during the operation
+  //! due to projection of the edges on the planes for creation of 2D curves.<br>
+  //! Parameters:
+  //! <theWires> - the given wires;<br>
+  //! <theFaces> - the output faces;<br>
+  //! <theAngTol> - the angular tolerance for distinguishing the planes in which
+  //!               the wires are located. Default value is 1.e-8 which is used
+  //!               for intersection of planes in IntTools_FaceFace.<br>
+  //! Method returns TRUE in case of success, i.e. at least one face has been built.<br>
+  Standard_EXPORT static Standard_Boolean WiresToFaces(const TopoDS_Shape& theWires,
+                                                       TopoDS_Shape& theFaces,
+                                                       const Standard_Real theAngTol = 1.e-8);
 };
 
 #endif // _BOPAlgo_Tools_HeaderFile