From a7d89710080a7b41105bd796477014cb05c4d9b2 Mon Sep 17 00:00:00 2001
From: msv <msv@opencascade.com>
Date: Fri, 29 Sep 2017 10:43:52 +0300
Subject: [PATCH] 0029159: Sewing fail when using a maximum tolerance

Force setting truly computed tolerance of the edge if BRepLib::SameParameter has put too large tolerance.
---
 src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx | 14 +++++++++-
 tests/bugs/modalg_7/bug29159                 | 29 ++++++++++++++++++++
 2 files changed, 42 insertions(+), 1 deletion(-)
 create mode 100644 tests/bugs/modalg_7/bug29159

diff --git a/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx b/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx
index ffe71aad90..ce5039ff8c 100644
--- a/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx
+++ b/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx
@@ -118,6 +118,7 @@
 #include <Geom_OffsetSurface.hxx>
 #include <BRep_PointOnCurve.hxx>
 #include <BRep_ListOfPointRepresentation.hxx>
+#include <BRep_TEdge.hxx>
 #include <BRep_TVertex.hxx>
 #include <Message_ProgressSentry.hxx>
 #include <BRepBuilderAPI_VertexInspector.hxx>
@@ -951,11 +952,22 @@ TopoDS_Edge BRepBuilderAPI_Sewing::SameParameterEdge(const TopoDS_Edge& edgeFirs
             if (dist > dist2) 
               dist2 = dist;
           }
-          maxTol = Max(sqrt(dist2), Precision::Confusion());
+          maxTol = Max(sqrt(dist2) * (1. + 1e-7), Precision::Confusion());
         }
       }
       if(maxTol >= 0. && maxTol < tolReached)
+      {
+        if (tolReached > MaxTolerance())
+        {
+          // Set tolerance directly to overwrite too large tolerance
+          static_cast<BRep_TEdge*>(edge.TShape().operator->())->Tolerance(maxTol);
+        }
+        else
+        {
+          // just update tolerance with computed distance
         aBuilder.UpdateEdge(edge, maxTol);
+        }
+      }
       aBuilder.SameParameter(edge,Standard_True);
     }
   }
diff --git a/tests/bugs/modalg_7/bug29159 b/tests/bugs/modalg_7/bug29159
new file mode 100644
index 0000000000..21397f9cd6
--- /dev/null
+++ b/tests/bugs/modalg_7/bug29159
@@ -0,0 +1,29 @@
+puts "========"
+puts "OCC29159"
+puts "========"
+puts ""
+#################################################
+# Sewing fail when using a maximum tolerance
+#################################################
+
+set MaxTol 5e-4
+set ExpLength 97.234
+
+restore [locate_data_file bug29159_F.brep] f
+sewing result 5e-4 f +mint 1e-8 +maxt $MaxTol
+
+regexp {EDGE *: MAX=([-0-9.+eE]+)} [tolerance result] full toler
+
+if {$toler > $MaxTol} {
+  puts "Error: Tolerance after sewing is greater than max allowed tolerance"
+}
+
+if {![regexp "seems to be OK" [bopcheck result 2]]} {
+  puts "Error: result of sewing is self-interfering"
+}
+
+checknbshapes result -m "Sewing result" -edge 8 -face 2
+
+smallview +X+Y
+don result
+fit
-- 
2.39.5