Part: TopoShape: add generalFuse method (GFA)

OCC's Generaal Fuse Algorithm

src/Mod/Part/App/TopoShape.cpp

@@ -1510,6 +1510,42 @@ TopoDS_Compound TopoShape::slices(const Base::Vector3d& dir, const std::vector<d
     return comp;
 }
 
+TopoDS_Shape TopoShape::generalFuse(const std::vector<TopoDS_Shape> &sOthers, Standard_Real tolerance, std::vector<TopTools_ListOfShape>* mapInOut) const
+{
+    if (this->_Shape.IsNull())
+        Standard_Failure::Raise("Base shape is null");
+#if OCC_VERSION_HEX <= 0x060900
+    throw Base::Exception("GFA is available only in OCC 6.9.0 and up.");
+#else
+    BRepAlgoAPI_BuilderAlgo mkGFA;
+    TopTools_ListOfShape GFAArguments;
+    GFAArguments.Append(this->_Shape);
+    for (const TopoDS_Shape &it: sOthers) {
+        if (it.IsNull())
+            throw Base::Exception("Tool shape is null");
+        if (tolerance > 0.0)
+            // workaround for http://dev.opencascade.org/index.php?q=node/1056#comment-520
+            GFAArguments.Append(BRepBuilderAPI_Copy(it).Shape());
+        else
+            GFAArguments.Append(it);
+    }
+    mkGFA.SetArguments(GFAArguments);
+    if (tolerance > 0.0)
+        mkGFA.SetFuzzyValue(tolerance);
+    mkGFA.SetNonDestructive(Standard_True);
+    mkGFA.Build();
+    if (!mkGFA.IsDone())
+        throw Base::Exception("MultiFusion failed");
+    TopoDS_Shape resShape = mkGFA.Shape();
+    if (mapInOut){
+        for(TopTools_ListIteratorOfListOfShape it(GFAArguments); it.More(); it.Next()){
+            mapInOut->push_back(mkGFA.Modified(it.Value()));
+        }
+    }
+    return resShape;
+#endif
+}
+
 TopoDS_Shape TopoShape::makePipe(const TopoDS_Shape& profile) const
 {
     if (this->_Shape.IsNull())

src/Mod/Part/App/TopoShape.h

@@ -153,6 +153,28 @@ class PartExport TopoShape : public Data::ComplexGeoData
     TopoDS_Shape section(TopoDS_Shape) const;
     std::list<TopoDS_Wire> slice(const Base::Vector3d&, double) const;
     TopoDS_Compound slices(const Base::Vector3d&, const std::vector<double>&) const;
+    /**
+     * @brief generalFuse: run general fuse algorithm between this and shapes
+     * supplied as sOthers
+     *
+     * @param sOthers (input): list of shapes to run the algorithm between
+     * (this is automatically added to the list)
+     *
+     * @param tolerance (input): fuzzy value (pass zero to disable fuzzyness
+     * and use shape tolerances only)
+     *
+     * @param mapInOut (output): pointer to list of lists, to write the info
+     * which shapes in result came from which argument shape. The length of
+     * list is equal to length of sOthers+1. First element is a list of shapes
+     * that came from shape of this, and the rest are those that come from
+     * shapes in sOthers. If the info is not needed, nullptr can be passed.
+     *
+     * @return compound of slices that can be combined to reproduce results of
+     * cut, fuse, common. The shapes share edges and faces where they touch.
+     * For example, if input shapes are two intersecting spheres, GFA returns
+     * three solids: two cuts and common.
+     */
+    TopoDS_Shape generalFuse(const std::vector<TopoDS_Shape> &sOthers, Standard_Real tolerance, std::vector<TopTools_ListOfShape>* mapInOut = nullptr) const;
     //@}
 
     /** Sweeping */