From 1a060fcf2182deca7060e1e5de7177c9986da06c Mon Sep 17 00:00:00 2001
From: nbv <nbv@opencascade.com>
Date: Tue, 22 Sep 2015 13:35:13 +0300
Subject: [PATCH] 0026632: HLR sample doesn't work with Algo mode

The main reason of the problem is Walking-line contains two equal Walking-points (the segment has null-length both in 3D and 2D).
---
 src/IntWalk/IntWalk_IWalking_5.gxx | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/IntWalk/IntWalk_IWalking_5.gxx b/src/IntWalk/IntWalk_IWalking_5.gxx
index ca67056f06..b3454916a1 100644
--- a/src/IntWalk/IntWalk_IWalking_5.gxx
+++ b/src/IntWalk/IntWalk_IWalking_5.gxx
@@ -109,8 +109,14 @@ IntWalk_StatusDeflection IntWalk_IWalking::TestDeflection
 
   const Standard_Real aMinTolU = 0.1*Abs(Step*previousd2d.X()),
                       aMinTolV = 0.1*Abs(Step*previousd2d.Y());
+  const Standard_Real aTolU = (aMinTolU > 0.0) ? Min(tolerance(1), aMinTolU) : tolerance(1),
+                      aTolV = (aMinTolV > 0.0) ? Min(tolerance(2), aMinTolV) : tolerance(2);
 
-  if ((Abs(Du) < Min(tolerance(1), aMinTolU)) && (Abs(Dv) < Min(tolerance(2), aMinTolV)))
+  //If aMinTolU==0.0 then (Abs(Du) < aMinTolU) is equivalent of (Abs(Du) < 0.0).
+  //It is impossible. Therefore, this case should be processed separately.
+  //Analogicaly for aMinTolV.
+
+  if ((Abs(Du) < aTolU) && (Abs(Dv) < aTolV))
   {
     //Thin shapes (for which Ulast-Ufirst or/and Vlast-Vfirst is quite small)
     //exists (see bug #25820). In this case, step is quite small too.