[vtkusers] Compiling Error

[Michael Györffy]

Hello:
	I'm new to vtk and programming. I'm using the following script:

vtkPolyDataToImageStencil *dataToStencil=vtkPolyDataToImageStencil::New();
	dataToStencil->SetInput(pdata->GetOutput());

	Where pdata is Polydata.
        I'm getting the following error to these two lines: "undefined
reference to `vtkPolyDataToImageStencil::New(void)'"
	and
"undefined reference to `vtkPolyDataToImageStencil::SetInput(vtkPolyData *)'"

	What does this "undefined reference to" error mean and how can I
fix this problem?

	A google of thanks,

	Mike