Add BRepExtrema_DistShapeShape option to tree with extend keyword

src/ifcgeom/IfcGeomTree.h

@@ -30,6 +30,7 @@
 #include <Bnd_Box.hxx>
 #include <BRepAlgoAPI_Common.hxx>
 #include <BRepAlgoAPI_Cut.hxx>
+#include <BRepExtrema_DistShapeShape.hxx>
 #include <BRepClass3d_SolidClassifier.hxx>
 
 namespace IfcGeom {
@@ -38,6 +39,30 @@ namespace IfcGeom {
 		template <typename T>
 		class tree {
 
+			bool test(const TopoDS_Shape& A, const TopoDS_Shape& B, bool completely_within, double extend) const {
+				if (extend > 0.) {
+					BRepExtrema_DistShapeShape dss(A, B);
+					if (dss.Perform() && dss.NbSolution() >= 1) {
+						return dss.Value() <= extend;
+					}
+				} else if (completely_within) {
+					BRepAlgoAPI_Cut cut(B, A);
+					if (cut.IsDone()) {
+						if (IfcGeom::Kernel::count(cut.Shape(), TopAbs_SHELL) == 0) {
+							return true;
+						}
+					}
+				} else {
+					BRepAlgoAPI_Common common(A, B);
+					if (common.IsDone()) {
+						if (IfcGeom::Kernel::count(common.Shape(), TopAbs_SHELL) > 0) {
+							return true;
+						}
+					}
+				}
+				return false;
+			}
+
 		public:
 
 			void add(const T& t, const Bnd_Box& b) {
@@ -104,8 +129,8 @@ namespace IfcGeom {
 				}
 			}
 
-			std::vector<T> select(const T& t, bool completely_within = false) const {
+			std::vector<T> select(const T& t, bool completely_within = false, double extend = 0.0) const {
-				std::vector<T> ts = select_box(t);
+				std::vector<T> ts = select_box(t, completely_within, extend);
 				if (ts.empty()) {
 					return ts;
 				}
@@ -126,29 +151,18 @@ namespace IfcGeom {
 						continue;
 					}
 
-					if (completely_within) {
+					if (test(A, B, completely_within, extend)) {
-						BRepAlgoAPI_Cut cut(B, A);
+						ts_filtered.push_back(*it);
-						if (cut.IsDone()) {
-							if (IfcGeom::Kernel::count(cut.Shape(), TopAbs_SHELL) == 0) {
-								ts_filtered.push_back(*it);
-							}
-						}
-					} else {
-						BRepAlgoAPI_Common common(A, B);
-						if (common.IsDone()) {
-							if (IfcGeom::Kernel::count(common.Shape(), TopAbs_SHELL) > 0) {
-								ts_filtered.push_back(*it);
-							}
-						}
 					}
 				}
 
 				return ts_filtered;
 			}
 
-			std::vector<T> select(const TopoDS_Shape& s) const {
+			std::vector<T> select(const TopoDS_Shape& s, bool completely_within = false, double extend = -1.e-5) const {
 				Bnd_Box bb;
 				BRepBndLib::AddClose(s, bb);
+				bb.SetGap(bb.GetGap() + extend);
 
 				std::vector<T> ts;
 
@@ -156,7 +170,7 @@ namespace IfcGeom {
 					return ts;
 				}
 
-				ts = select_box(bb);
+				ts = select_box(bb, completely_within);
 
 				if (ts.empty()) {
 					return ts;
@@ -168,16 +182,13 @@ namespace IfcGeom {
 				typename std::vector<T>::const_iterator it = ts.begin();
 				for (it = ts.begin(); it != ts.end(); ++it) {
 					const TopoDS_Shape& B = shapes_.find(*it)->second;
-					
+
 					if (IfcGeom::Kernel::count(B, TopAbs_SHELL) == 0) {
 						continue;
 					}
 
-					BRepAlgoAPI_Common common(s, B);
+					if (test(s, B, completely_within, extend)) {
-					if (common.IsDone()) {
+						ts_filtered.push_back(*it);
-						if (IfcGeom::Kernel::count(common.Shape(), TopAbs_SHELL) > 0) {
-							ts_filtered.push_back(*it);
-						}
 					}
 				}
 
@@ -258,6 +269,10 @@ namespace IfcGeom {
 			add_file(f, settings);
 		}
 
+		tree(IfcGeom::Iterator<double>& it) {
+			add_file(it);
+		}		
+
 		void add_file(IfcParse::IfcFile& f, const IfcGeom::IteratorSettings& settings) {
 			IfcGeom::IteratorSettings settings_ = settings;
 			settings_.set(IfcGeom::IteratorSettings::DISABLE_TRIANGULATION, true);
@@ -266,10 +281,14 @@ namespace IfcGeom {
 
 			IfcGeom::Iterator<double> it(settings_, &f);
 
+			add_file(it);
+		}
+
+		void add_file(IfcGeom::Iterator<double>& it) {
 			if (it.initialize()) {
 				do {
 					IfcGeom::BRepElement<double>* elem = (IfcGeom::BRepElement<double>*)it.get();
-					add((IfcUtil::IfcBaseEntity*)f.instance_by_id(elem->id()), elem->geometry().as_compound());
+					add((IfcUtil::IfcBaseEntity*)it.file()->instance_by_id(elem->id()), elem->geometry().as_compound());
 				} while (it.next());
 			}
 		}