From aaea1b933ca0f6037f154e2f7a83c362c7124c17 Mon Sep 17 00:00:00 2001
From: logari81 <logari81@e8eeb9e2-ec13-0410-a4a9-efa5cf37419d>
Date: Thu, 17 Nov 2011 19:58:45 +0000
Subject: [PATCH] + try to make the SQP solver in the Sketcher more robust

git-svn-id: https://free-cad.svn.sourceforge.net/svnroot/free-cad/trunk@5148 e8eeb9e2-ec13-0410-a4a9-efa5cf37419d
---
 src/Mod/Sketcher/App/freegcs/GCS.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Mod/Sketcher/App/freegcs/GCS.cpp b/src/Mod/Sketcher/App/freegcs/GCS.cpp
index 5ca29a71c..fb8c78f2a 100644
--- a/src/Mod/Sketcher/App/freegcs/GCS.cpp
+++ b/src/Mod/Sketcher/App/freegcs/GCS.cpp
@@ -984,11 +984,15 @@ int System::solve(SubSystem *subsysA, SubSystem *subsysB, bool isFine)
                         break;
                 }
                 alpha = tau * alpha;
+                if (alpha < 1e-8) // let the linesearch fail
+                    alpha = 0.;
                 x = x0 + alpha * xdir;
                 subsysA->setParams(plist,x);
                 subsysB->setParams(plist,x);
                 subsysA->calcResidual(resA);
                 f = subsysB->error() + mu * resA.lpNorm<1>();
+                if (alpha < 1e-8) // let the linesearch fail
+                    break;
             }
             lambda = lambda0 + alpha * lambdadir;