From df2bcecf96bc009081ad2e341d98df4c6fed7d84 Mon Sep 17 00:00:00 2001
From: Thomas Krijnen <t.krijnen@gmail.com>
Date: Tue, 20 Mar 2012 09:32:51 +0000
Subject: [PATCH] - Fix a regression due to too high tolerance in Polyline
 -Loop creation. - Make tolerances slightly more explicit, ideally these
 should obviously be configurable at runtime.

---
 src/ifcgeom/IfcGeom.h            | 8 ++++++++
 src/ifcgeom/IfcGeomFunctions.cpp | 8 ++++----
 src/ifcgeom/IfcGeomObjects.cpp   | 2 +-
 src/ifcgeom/IfcGeomWires.cpp     | 8 ++++----
 4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/ifcgeom/IfcGeom.h b/src/ifcgeom/IfcGeom.h
index 9040d5f50a..dbe9d78412 100644
--- a/src/ifcgeom/IfcGeom.h
+++ b/src/ifcgeom/IfcGeom.h
@@ -42,6 +42,14 @@
 
 #include "../ifcgeom/IfcShapeList.h"
 
+// Tolerances for various geometrical operations:
+// Specifies the deflection of the mesher
+#define DEFLECTION_TOLERANCE 0.001
+// Specifies the tolerance of the wire builder, most notably for trimmed curves
+#define WIRE_CREATION_TOLERANCE 0.0001
+// Specifies the treshold distance under which cartesian points are deemed equal
+#define POINT_EQUALITY_TOLERANCE 0.000001
+
 #define FACESET_AS_COMPOUND 1
 
 namespace IfcGeom {
diff --git a/src/ifcgeom/IfcGeomFunctions.cpp b/src/ifcgeom/IfcGeomFunctions.cpp
index 4b768921b0..915e83c8c4 100644
--- a/src/ifcgeom/IfcGeomFunctions.cpp
+++ b/src/ifcgeom/IfcGeomFunctions.cpp
@@ -278,8 +278,8 @@ bool IfcGeom::is_convex(const TopoDS_Wire& wire) {
 				edge_points.push_back(P2);
 			}
 			if ( edge_points.size() != 2 ) continue;
-			if ( edge_points[0].IsEqual(P1,0.0001)) neighbors.push_back(edge_points[1]);
-			else if ( edge_points[1].IsEqual(P1,0.0001)) neighbors.push_back(edge_points[0]);
+			if ( edge_points[0].IsEqual(P1,POINT_EQUALITY_TOLERANCE)) neighbors.push_back(edge_points[1]);
+			else if ( edge_points[1].IsEqual(P1,POINT_EQUALITY_TOLERANCE)) neighbors.push_back(edge_points[0]);
 		}
 		// There should be two of these
 		if ( neighbors.size() != 2 ) return false;
@@ -288,10 +288,10 @@ bool IfcGeom::is_convex(const TopoDS_Wire& wire) {
 		for ( TopExp_Explorer exp2(wire,TopAbs_VERTEX); exp2.More(); exp2.Next() ) {
 			TopoDS_Vertex V2 = TopoDS::Vertex(exp2.Current());
 			gp_Pnt P2 = BRep_Tool::Pnt(V2);
-			if ( P1.IsEqual(P2,0.0001) ) continue;
+			if ( P1.IsEqual(P2,POINT_EQUALITY_TOLERANCE) ) continue;
 			bool found = false;
 			for( std::vector<gp_Pnt>::const_iterator it = neighbors.begin(); it != neighbors.end(); ++ it ) {
-				if ( (*it).IsEqual(P2,0.0001) ) { found = true; break; }
+				if ( (*it).IsEqual(P2,POINT_EQUALITY_TOLERANCE) ) { found = true; break; }
 			}
 			if ( ! found ) non_neighbors.push_back(P2);
 		}
diff --git a/src/ifcgeom/IfcGeomObjects.cpp b/src/ifcgeom/IfcGeomObjects.cpp
index b47333efb7..2e7b6058b4 100644
--- a/src/ifcgeom/IfcGeomObjects.cpp
+++ b/src/ifcgeom/IfcGeomObjects.cpp
@@ -103,7 +103,7 @@ IfcGeomObjects::IfcMesh::IfcMesh(int i, const IfcGeom::ShapeList& shapes) {
 		// Triangulate the shape
 		try {
 			//BRepTools::Clean(s);
-			BRepMesh::Mesh(s,0.001f);
+			BRepMesh::Mesh(s,DEFLECTION_TOLERANCE);
 		} catch(...) {
 			Ifc::LogMessage("Error","Failed to triangulate mesh:",Ifc::EntityById(i)->entity);
 			continue;
diff --git a/src/ifcgeom/IfcGeomWires.cpp b/src/ifcgeom/IfcGeomWires.cpp
index e32b64f9e4..d1258541ec 100644
--- a/src/ifcgeom/IfcGeomWires.cpp
+++ b/src/ifcgeom/IfcGeomWires.cpp
@@ -114,7 +114,7 @@ bool IfcGeom::convert(const Ifc2x3::IfcCompositeCurve::ptr l, TopoDS_Wire& wire)
 		}
 		if ( ! (*it)->SameSense() ) wire2.Reverse();
 		ShapeFix_ShapeTolerance FTol;
-		FTol.SetTolerance(wire2, 0.0001, TopAbs_WIRE);
+		FTol.SetTolerance(wire2, WIRE_CREATION_TOLERANCE, TopAbs_WIRE);
 		/*if ( it != segments->begin() ) {
 			TopExp_Explorer exp (wire2,TopAbs_VERTEX);
 			const TopoDS_Vertex& first_vertex = TopoDS::Vertex(exp.Current());
@@ -201,7 +201,7 @@ bool IfcGeom::convert(const Ifc2x3::IfcPolyline::ptr l, TopoDS_Wire& result) {
 	gp_Pnt P1;gp_Pnt P2;
 	for( Ifc2x3::IfcCartesianPoint::it it = points->begin(); it != points->end(); ++ it ) {
 		IfcGeom::convert(*it,P2);
-		if ( it != points->begin() && ( !P1.IsEqual(P2,0.0001) ) )
+		if ( it != points->begin() && ( !P1.IsEqual(P2,POINT_EQUALITY_TOLERANCE) ) )
 			w.Add(BRepBuilderAPI_MakeEdge(P1,P2));
 		P1 = P2;
 	}
@@ -217,13 +217,13 @@ bool IfcGeom::convert(const Ifc2x3::IfcPolyLoop::ptr l, TopoDS_Wire& result) {
 	int count = 0;
 	for( Ifc2x3::IfcCartesianPoint::it it = points->begin(); it != points->end(); ++ it ) {
 		IfcGeom::convert(*it,P2);
-		if ( it != points->begin() && ( !P1.IsEqual(P2,0.0001) ) ) {
+		if ( it != points->begin() && ( !P1.IsEqual(P2,POINT_EQUALITY_TOLERANCE) ) ) {
 			w.Add(BRepBuilderAPI_MakeEdge(P1,P2));
 			count ++;
 		} else if ( ! count ) F = P2;		
 		P1 = P2;
 	}
-	if ( !P1.IsEqual(F,0.0001) ) {
+	if ( !P1.IsEqual(F,POINT_EQUALITY_TOLERANCE) ) {
 		w.Add(BRepBuilderAPI_MakeEdge(P1,F));
 		count ++;
 	}