From 02bd5b1cb4b19a6659dd5f2b69e43711ff590097 Mon Sep 17 00:00:00 2001
From: epernod <erik.pernod@gmail.com>
Date: Thu, 28 May 2026 11:56:25 +0200
Subject: [PATCH 1/2] [src] Add option to get the tip dof id of a beam/wire

---
 src/BeamAdapter/component/BaseBeamInterpolation.h   | 3 +++
 src/BeamAdapter/component/BaseBeamInterpolation.inl | 5 +++++
 2 files changed, 8 insertions(+)

diff --git a/src/BeamAdapter/component/BaseBeamInterpolation.h b/src/BeamAdapter/component/BaseBeamInterpolation.h
index 4d91ae1a1..a76f85b03 100644
--- a/src/BeamAdapter/component/BaseBeamInterpolation.h
+++ b/src/BeamAdapter/component/BaseBeamInterpolation.h
@@ -231,6 +231,9 @@ class BaseBeamInterpolation : public sofa::core::behavior::SingleStateAccessor<D
     Data< sofa::type::vector<EdgeID> > d_beamCollision;
 
     Data<bool>          d_dofsAndBeamsAligned;
+
+    /// index of the beam extremity that is considered as the tip of the wire
+	Data <sofa::Index> d_wireTipIndex;
     
     /// link to the (edge) topology
     SingleLink<BaseBeamInterpolation<DataTypes>, BaseMeshTopology, BaseLink::FLAG_STOREPATH|BaseLink::FLAG_STRONGLINK> l_topology;
diff --git a/src/BeamAdapter/component/BaseBeamInterpolation.inl b/src/BeamAdapter/component/BaseBeamInterpolation.inl
index d87ae05d8..d2264b3bd 100644
--- a/src/BeamAdapter/component/BaseBeamInterpolation.inl
+++ b/src/BeamAdapter/component/BaseBeamInterpolation.inl
@@ -107,6 +107,7 @@ BaseBeamInterpolation<DataTypes>::BaseBeamInterpolation()
     , d_beamCollision(initData(&d_beamCollision, "beamCollision", "list of beam (in edgeList) that needs to be considered for collision"))
     , d_dofsAndBeamsAligned(initData(&d_dofsAndBeamsAligned, true, "dofsAndBeamsAligned",
         "if false, a transformation for each beam is computed between the DOF and the beam nodes"))
+	, d_wireTipIndex(initData(&d_wireTipIndex, (sofa::Index)0, "wireTipIndex", "index of the beam extremity that is considered as the tip of the wire"))
     , l_topology(initLink("topology", "link to the topology (must contain edges)"))
 {
 
@@ -186,6 +187,9 @@ void BaseBeamInterpolation<DataTypes>::addBeam(const EdgeID eID, const Real leng
     d_dofsAndBeamsAligned.setValue(false);
     DOF0TransformNode0.push_back(Transform(Vec3(0, 0, 0), QuatX));
     DOF1TransformNode1.push_back(Transform(Vec3(0, 0, 0), QuatX));
+
+    const BaseMeshTopology::Edge& edge = l_topology->getEdge(eID);
+	d_wireTipIndex.setValue(edge[1]);
 }
 
 
@@ -392,6 +396,7 @@ void BaseBeamInterpolation<DataTypes>::getTangent(Vec3& t, const Real baryCoord,
 }
 
 
+// TODO check why this method is called in continue
 template<class DataTypes>
 int BaseBeamInterpolation<DataTypes>::getNodeIndices(const EdgeID edgeInList,
     unsigned int& node0Idx,

From b3ddf3238c0d86fd4bb328a556e645c7b6e5ded7 Mon Sep 17 00:00:00 2001
From: erik pernod <erik.pernod@gmail.com>
Date: Mon, 28 Sep 2026 22:00:06 +0200
Subject: [PATCH 2/2] Add null check for l_topology in BaseBeamInterpolation

Add null check for l_topology before accessing edge.
---
 src/BeamAdapter/component/BaseBeamInterpolation.inl | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/BeamAdapter/component/BaseBeamInterpolation.inl b/src/BeamAdapter/component/BaseBeamInterpolation.inl
index d2264b3bd..2951a8518 100644
--- a/src/BeamAdapter/component/BaseBeamInterpolation.inl
+++ b/src/BeamAdapter/component/BaseBeamInterpolation.inl
@@ -188,8 +188,11 @@ void BaseBeamInterpolation<DataTypes>::addBeam(const EdgeID eID, const Real leng
     DOF0TransformNode0.push_back(Transform(Vec3(0, 0, 0), QuatX));
     DOF1TransformNode1.push_back(Transform(Vec3(0, 0, 0), QuatX));
 
-    const BaseMeshTopology::Edge& edge = l_topology->getEdge(eID);
-	d_wireTipIndex.setValue(edge[1]);
+	if (l_topology)
+    {
+        const BaseMeshTopology::Edge& edge = l_topology->getEdge(eID);
+	    d_wireTipIndex.setValue(edge[1]);
+    }
 }