[vtkusers] ICP algorithm giving eigenfunctions errors

[Sean Snyders]

Hi,

I use the example from:
http://www.vtk.org/Wiki/Iterative_Closest_Points_(ICP)_Transform

and do a direct translation thereof in python (see code listed below).
When I run the code, I get this warning:
--------------
Generic Warning: In ........./Common/vtkMath.cxx, line 758
vtkMath::Jacobi: Error extracting eigenfunctions
------------

and my output transformed points are then:
------------------
xformed source point[0]=[nan, nan, nan]
xformed source point[1]=[nan, nan, nan]
xformed source point[2]=[nan, nan, nan]
-----------------

Should this example not work? I have not tested this with the c++ 
implementation, but surely it should work.

Thanks!
Sean.


#--------------------------------------------------------------------------------------------------------------
    def initData(self):
        # ============ source points ==============
        sourcePoints = vtk.vtkPoints()
        sourceVertices = vtk.vtkCellArray()

        id = sourcePoints.InsertNextPoint(1.0, 0.1, 0.0)
        sourceVertices.InsertNextCell(id)
       
        id = sourcePoints.InsertNextPoint(0.1, 1.1, 0.0)
        sourceVertices.InsertNextCell(id)
       
        id = sourcePoints.InsertNextPoint(0.0, 0.1, 1.0)
        sourceVertices.InsertNextCell(id)
       
        self.source = vtk.vtkPolyData()
        self.source.SetPoints(sourcePoints)
        self.source.SetVerts(sourceVertices)
       
       
        pointCount = 3
        index = 0
        while index < pointCount:
            point = [0,0,0]
            sourcePoints.GetPoint(index, point)
            print "source point[%s]=%s" % (index,point)
            index += 1
       
        #============ target points ==============
       
        targetPoints = vtk.vtkPoints()
        targetVertices = vtk.vtkCellArray()
       
        id = targetPoints.InsertNextPoint(1.0, 0.0, 0.0)
        targetVertices.InsertNextCell(id)
       
        id = targetPoints.InsertNextPoint(0.1, 1.0, 0.0)
        targetVertices.InsertNextCell(id)
       
        id = targetPoints.InsertNextPoint(0.0, 0.0, 1.0)
        targetVertices.InsertNextCell(id)
       
        self.target = vtk.vtkPolyData()
        self.target.SetPoints(targetPoints)
        self.target.SetVerts(targetVertices)
   
        icp = vtk.vtkIterativeClosestPointTransform()
        icp.SetSource(self.source)
        icp.SetTarget(self.target)
        icp.GetLandmarkTransform().SetModeToRigidBody()
        #icp.DebugOn()
        icp.SetMaximumNumberOfIterations(20)
        icp.StartByMatchingCentroidsOn()
        icp.Modified()
        icp.Update()
       
        icpTransformFilter = vtk.vtkTransformPolyDataFilter()
        icpTransformFilter.SetInput(self.source)
        icpTransformFilter.SetTransform(icp)
        icpTransformFilter.Update()
       
        transformedSource = icpTransformFilter.GetOutput()
       
        pointCount = 3
        index = 0
        while index < pointCount:
            point = [0,0,0]
            transformedSource.GetPoint(index, point)
            print "xformed source point[%s]=%s" % (index,point)
            index += 1
#--------------------------------------------------------------------------------------------------------------s