Question about MeshVTKLoader

[ldi4]

HI all,
I am trying to load my soft robot for some simulation but some warning emerged under expectation, i am able to locate the problem with this line of code:

    finger.addObject('MeshVTKLoader', name='loader', filename='/home/lingy/Downloads/catheter.vtk')

The terminal give me tens of lines of warning [BaseObject(unnamed)] unknow keyword (some random characters) and then:

########## SIG 11 - SIGSEGV: segfault ##########
  sofa::helper::BackTrace::sig(int)
  sofa::component::io::mesh::MeshVTKLoader::setInputsMesh()
  sofa::component::io::mesh::MeshVTKLoader::doLoad()
  sofa::core::loader::MeshLoader::load()
  sofa::core::DataTrackerCallback::update()
  sofa::core::objectmodel::BaseData::update()
  sofa::core::objectmodel::Data<sofa::type::vector<sofa::type::Vec<3u, double>, sofa::type::CPUMemoryManager<sofa::type::Vec<3u, double> > > >::beginEdit()
  sofa::core::loader::MeshLoader::applyTransformation(sofa::type::Mat<4u, 4u, double> const&)
  sofa::core::loader::MeshLoader::reinit()
  sofa::simulation::InitVisitor::processNodeTopDown(sofa::simulation::Node*)
  sofa::simulation::graph::DAGNode::executeVisitorTopDown(sofa::simulation::Visitor*, std::__cxx11::list<sofa::simulation::graph::DAGNode*, std::allocator<sofa::simulation::graph::DAGNode*> >&, std::map<sofa::simulation::graph::DAGNode*, sofa::simulation::graph::DAGNode::StatusStruct, std::less<sofa::simulation::graph::DAGNode*>, std::allocator<std::pair<sofa::simulation::graph::DAGNode* const, sofa::simulation::graph::DAGNode::StatusStruct> > >&, sofa::simulation::graph::DAGNode*)
  sofa::simulation::graph::DAGNode::executeVisitorTopDown(sofa::simulation::Visitor*, std::__cxx11::list<sofa::simulation::graph::DAGNode*, std::allocator<sofa::simulation::graph::DAGNode*> >&, std::map<sofa::simulation::graph::DAGNode*, sofa::simulation::graph::DAGNode::StatusStruct, std::less<sofa::simulation::graph::DAGNode*>, std::allocator<std::pair<sofa::simulation::graph::DAGNode* const, sofa::simulation::graph::DAGNode::StatusStruct> > >&, sofa::simulation::graph::DAGNode*)
  sofa::simulation::graph::DAGNode::doExecuteVisitor(sofa::simulation::Visitor*, bool)
  sofa::simulation::Simulation::initNode(sofa::simulation::Node*)
  sofa::simulation::Simulation::init(sofa::simulation::Node*)
  PyCFunction_Call
  _PyObject_MakeTpCall
  _PyEval_EvalFrameDefault
  _PyFunction_Vectorcall
  _PyEval_EvalFrameDefault
  _PyEval_EvalCodeWithName
  PyEval_EvalCode
  PyRun_SimpleFileExFlags
  Py_RunMain
  Py_BytesMain
  __libc_start_main
  _start
Segmentation fault (core dumped); 

I feel like the problem is about the .vtk file. I generate my vtk mesh using meshio in python from a stl file. Really appreciate any form of help.

[hugtalbot]

Hi @ldi4

thanks for the question
Indeed could you share:

• your vtk file
• the full scene output (since the opening till the crash)

thanks in advance

[ldi4]

Hi Hugo!

Very glad to have your help! Your tutorial really helps me a lot! I dont know how to share vtk file in github forum so I made a zip including my python file and all mesh.
sofa_proj.zip

Really appreciate your help in advance!

[hugtalbot]

Hi @ldi4
I reproduced the issue locally, our MeshVTKLoader seems indeed to have some issue with modern vtk formating.
We will investigate this. Thanks!

PS: note that your vtk mesh is only a surface mesh

[hugtalbot]

An unsatisfactory hack is proposed in ##3385
But I updated the associated issue #3405 to raise this issue with devs

[ldi4]

I see, I will try to convert the .vtk version and see how's it going.

[hugtalbot]

Thanks 🙏 we will take a look at it at our next dev committee. Keep us posted @ldi4

[ldi4]

Solved by using binary format vtk file generated by Gmsh instead of meshio